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  1. Community Environmental Response Facilitation Act (CERFA) report. Fort Des Moines, Des Moines, Iowa. Final report

    SciTech Connect (OSTI)

    Young, B.; Rausch, K.; Kang, J.

    1994-04-01

    This report presents the results of the Community Environmental Response Facilitation Act (CERFA) investigation conducted by The Earth Technology Corporation (TETC) at the Fort Des Moines, a U.S. Government property selected for closure by the Base Realignment and Closure (BRAC) Commission. Under CERFA Federal agencies are required to identify real property that can be immediately reused and redeveloped. Satisfying this objective requires the identification of real property where no hazardous substances or petroleum products, regulated by the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA), were stored for one year or more, known to have been released, or disposed. Fort Des Moines is a 53.28-acre site located in Polk County, Iowa, within the city limits of Des Moines. The installation's primary mission is to provide support and shelter for the U.S. Army Reserve. Activities associated with the property that have environmental significance are photographic processing, vehicle maintenance, printing, and fuel storage. TETC reviewed existing investigation documents; U.S. Environmental Protection Agency (USEPA), State, and county regulatory records; environmental data bases; and title documents pertaining to Fort Des Moines during this investigation. In addition, TETC conducted interviews and visual inspections of Fort Des Moines as well as visual inspections and data base searches for the surrounding properties. Information in this CERFA Report was current as of April 1994.

  2. Des Moines Area Community College | OSTI, US Dept of Energy Office of

    Office of Scientific and Technical Information (OSTI)

    Scientific and Technical Information Des Moines Area Community College Spotlights Home DOE Applauds Des Moines Area Community College Science and Technical Programs Des Moines Area Community College Des Moines Area Community College Des Moines, Iowa Agri/Natural Resources Biology Biomass Operations Biotechnology Environmental Science Information Technology Manufacturing Technology Microcomputers Civil Engineering Pre-Medical Telecommunications Wind Turbines Resource Links About Library

  3. West Des Moines, Iowa: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    Hide Map This article is a stub. You can help OpenEI by expanding it. West Des Moines is a city in Dallas County and Polk County and Warren County, Iowa. It falls...

  4. Des Moines, Washington: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    This article is a stub. You can help OpenEI by expanding it. Des Moines is a city in King County, Washington. It falls under Washington's 9th congressional district.12...

  5. QER SECOND INSTALLMENT REGIONAL MEETING--DES MOINES, IOWA | Department of

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Energy DES MOINES, IOWA QER SECOND INSTALLMENT REGIONAL MEETING--DES MOINES, IOWA MEETING DATE AND LOCATION Friday, May 6, 2016 Doors open: 8:00 AM, Program begins: 8:30 AM State Historical Building 600 East Locust Street Des Moines, IA 50319 Watch the May 6th Des Moines regional meeting here. MEETING INFORMATION The Quadrennial Energy Review Task Force will host a public stakeholder meeting on the second installment of the Quadrennial Energy Review (QER), an integrated study of the U.S.

  6. Superfund Record of Decision (EPA Region 7): Des Moines TCE Site, Operable Unit 3, Des Moines, IA. (Second remedial action), September 1992. Final report

    SciTech Connect (OSTI)

    Not Available

    1992-09-18

    The Des Moines TCE site is located southwest of downtown Des Moines, Polk County, Iowa. Land use in the area is predominantly industrial and commercial, and part of the site lies within the floodplain of the Raccoon River. Water from the Des Moines Water Works north infiltration gallery was found to be contaminated with trichloroethylene (TCE), dichloroethylene (DCE), and vinyl chloride at levels above accepted drinking water standards. The ROD addresses OU3, which encompasses potential sources of ground water contamination in an area north of the Raccoon River. The selected remedial action for OU3 includes no action with periodic groundwater monitoring.

  7. After 105 Years, Historic City Hall in West Des Moines, Iowa...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    ... credit: Vicky Saylor EECBG Success Story: After 105 Years, Historic City Hall in West Des Moines, Iowa Goes Green Using money from the Energy Efficiency Block Grant Program, St. ...

  8. EECBG Success Story: After 105 Years, Historic City Hall in West Des Moines, Iowa Goes Green

    Broader source: Energy.gov [DOE]

    The city of West Des Moines, Iowa is used funding to renovate the Historic City Hall building located in Valley Junction, including the installation of four geothermal heating wells, a rooftop covered with vegetation, solar panels and permeable pavers to allow stormwater through to the soil below. Learn more.

  9. V-059: MoinMoin Multiple Vulnerabilities

    Broader source: Energy.gov [DOE]

    Multiple vulnerabilities have been reported in MoinMoin, which can be exploited by malicious users to conduct script insertion attacks and compromise a vulnerable system and by malicious people to manipulate certain data.

  10. Early Pennsylvanian wrenching along the Red River-Matador Arch: Formation of a pull-apart basin, Depocenter for Atokan to Lower Des Moines (bend) clastics, Cottle County, Texas

    SciTech Connect (OSTI)

    Stephens, W.C. Jr.; Gunn, R.D.

    1995-06-01

    Early Pennsylvanian wrenching along the Red River-Matador Arch (Tectonic Zone) created a braided series of en echelon faults and folds with associated pop-up structures and pull-apart basins. Local extension, or overstepping, in Southeast Cottle County, Texas, has produced the deepest pull-apart basin along the arch with over 10,000` of structural relief. The emerging Wichita-Amarillo Uplift, to the north, provided an abundant sediment source, which prograded rapidly southward as an alluvial fan-braided river complex. Exposure of basement rocks and lower Paleozoic sediments along the Red River-Matador Arch, also contributed to the basin fill. Syntectonic sedimentation led to the accumulation of over 6000` of Bend (Atoka-lower Des Moines) sediments within the basin. Deposition was dominated initially by alluvial fan to fluvial siliciclastics. As basin subsidence was further amplified by sediment loading, accommodation exceeded sedimentation capturing a large segment of the southward prograding Wichita-Amarillo derived clastic wedge. Encroachment of the late Atoka to lower Des Moines epeiric sea promoted further evolution of depositional environments to fan deltas, marine dominated clastics and, later, localized carbonate development. Type III kerogen rich organic shales produced abundant gas prone source rocks. The extreme depth of the basin combined with the local geothermal gradient provided for significant hydrocarbon generation. By early 1988 new well control helped revise previous stratigraphic correlation demonstrating a rapidly expanding lower Des Moines to Atokan section. The drilling of the Gunn Oil Company-Brothers No. 1 to a total depth of 10,301` in the Mississippian Chappel Limestone, encountered 2025` of Bend sediments, with 279` of gross Bend Conglomerate (162` of net pay). The Brothers No. 1 was potentialled on 11/19/89 with a CAOF of 6.0 MMCFD and filed as the field discovery for the Broken Bone (Bend Conglomerate) field.

  11. Des Moines Energy Center repowering with PCFB technology

    SciTech Connect (OSTI)

    Ambrose, S.J.; Kreumpel, G.E.; Dryden, R.

    1992-01-01

    Iowa Power and Dairyland Power have formed a partnership and entered into an agreement with the United States Department of Energy (DOE) to repower a mothballed electric generating facility using Pressurized Circulating Fluidized Bed (PCFB) combustion technology. The project is the first commercial application of PCFB technology. The project includes the refurbishment of an existing steam turbine cycle, installation of the PCFB and gas turbine, and a two year operating period to demonstrate the technology. The repowered unit is expected to be rated at 80 MW. The plant is scheduled to begin operation in 1996. Process systems are described.

  12. Des Moines Energy Center repowering with PCFB technology

    SciTech Connect (OSTI)

    Ambrose, S.J.; Kreumpel, G.E.; Dryden, R.

    1992-12-01

    Iowa Power and Dairyland Power have formed a partnership and entered into an agreement with the United States Department of Energy (DOE) to repower a mothballed electric generating facility using Pressurized Circulating Fluidized Bed (PCFB) combustion technology. The project is the first commercial application of PCFB technology. The project includes the refurbishment of an existing steam turbine cycle, installation of the PCFB and gas turbine, and a two year operating period to demonstrate the technology. The repowered unit is expected to be rated at 80 MW. The plant is scheduled to begin operation in 1996. Process systems are described.

  13. Magellan Final Report

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Magellan Report on Cloud Computing for Science U.S. Department of Energy Office of Advanced Scientific Computing Research (ASCR) December, 2011 CSO 23179 The Magellan Report on Cloud Computing for Science U.S. Department of Energy Office of Science Office of Advanced Scientific Computing Research (ASCR) December, 2011 Magellan Leads Katherine Yelick, Susan Coghlan, Brent Draney, Richard Shane Canon Magellan Staff Lavanya Ramakrishnan, Adam Scovel, Iwona Sakrejda, Anping Liu, Scott Campbell,

  14. CX-006500: Categorical Exclusion Determination

    Broader source: Energy.gov [DOE]

    Magellan Des Moines Biodiesel Terminal ProjectCX(s) Applied: B5.1Date: 09/06/2011Location(s): Des Moines, IowaOffice(s): Energy Efficiency and Renewable Energy, Golden Field Office

  15. Magellan-Tutorial.pptx

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Magellan A Test Bed to Explore Cloud Computing for Science Shane Canon and Lavanya Ramakrishnan Cray XE6 Training February 8, 2011 Magellan - Exploring Cloud Computing Co-located at two DOE-SC Facilities * Argonne Leadership Computing Facility (ALCF) * National Energy Research Scientific Computing Center (NERSC) * Funded by DOE under the American Recovery and Reinvestment Act (ARRA) 2 Magellan Mission * Determine the appropriate role for commercial and/or private cloud computing for DOE/SC

  16. Magellan: A Cloud Computing Testbed

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Magellan News & Announcements Archive Petascale Initiative Exascale Computing APEX Home » R & D » Archive » Magellan: A Cloud Computing Testbed Magellan: A Cloud Computing Testbed Cloud computing is gaining a foothold in the business world, but can clouds meet the specialized needs of scientists? That was one of the questions NERSC's Magellan cloud computing testbed explored between 2009 and 2011. The goal of Magellan, a project funded through the U.S. Department of Energy (DOE) Oce

  17. A Touch of Green for Des Moines’ Sherman Hill

    Broader source: Energy.gov [DOE]

    Des Moines' Green & Main intends to intends to renovate an abandoned 1930s grocery store into a mixed-use facility with LEED Platinum certification – a prestigious badge of energy efficiency and sustainable building practices.

  18. Magellan In the News

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    In the News Magellan In the News October 20, 2011 Articles About Magellan @ NERSC June 7, 2011, The case of the missing proton spin, symmetrybreaking June 1, 2011, The case of the missing proton spin, International Science Grid This Week (ISGTW) March 28, 2011, Why high-performance clouds are best kept in-house, Government Computing News Dec. 3, 2010, 2010 Annual HPCwire Readers' Choice Awards, HPCwire Autumn, 2010, Sensing the Future of Greener Data Centers, HPCsource Nov. 30, 2010, A List of

  19. Des Moines Area Community College | OSTI, US Dept of Energy Office...

    Office of Scientific and Technical Information (OSTI)

    DMACC Facebook DMACC Twitter DMACC YouTube Students Wind Energy and Technology Careers ... Loop Ankeny Campus Academic Achievement Center DMACC Video Magazine DMACC Operation Green

  20. Targeted Energy Efficiency Expert Evaluation Report: Neal Smith Federal Building, Des Moines, IA

    SciTech Connect (OSTI)

    Fernandez, Nicholas; Goddard, James K.; Underhill, Ronald M.; Gowri, Krishnan

    2013-03-01

    This report summarizes the energy efficiency measures identified and implemented, and an analysis of the energy savings realized using low-cost/no-cost control system measures identified.

  1. Magellan @ NERSC Pushes Energy Efficiency Envelope

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    @ NERSC Pushes Energy Efficiency Envelope Magellan @ NERSC Pushes Energy Efficiency Envelope February 23, 2011 At NERSC, the Magellan scientific cloud computing testbed is pushing the bounds of power and cooling efficiency. The system was not only installed to require less cooling energy, but it's also been configured to simulate a wide range of data center parameters and instrumented with sensors, allowing staff to study and tune Magellan's efficiency. Innovative Installation NERSC staff

  2. Magellan additional information | U.S. DOE Office of Science...

    Office of Science (SC) Website

    Miscellaneous ASCR Recovery Act Projects Magellan additional information Advanced Scientific Computing Research (ASCR) ASCR Home About Research Facilities Science Highlights ...

  3. Argonne's Magellan Cloud Computing Research Project

    ScienceCinema (OSTI)

    Beckman, Pete

    2013-04-19

    Pete Beckman, head of Argonne's Leadership Computing Facility (ALCF), discusses the Department of Energy's new $32-million Magellan project, which designed to test how cloud computing can be used for scientific research. More information: http://www.anl.gov/Media_Center/News/2009/news091014a.html

  4. The Magellan Final Report on Cloud Computing

    SciTech Connect (OSTI)

    ,; Coghlan, Susan; Yelick, Katherine

    2011-12-21

    The goal of Magellan, a project funded through the U.S. Department of Energy (DOE) Office of Advanced Scientific Computing Research (ASCR), was to investigate the potential role of cloud computing in addressing the computing needs for the DOE Office of Science (SC), particularly related to serving the needs of mid- range computing and future data-intensive computing workloads. A set of research questions was formed to probe various aspects of cloud computing from performance, usability, and cost. To address these questions, a distributed testbed infrastructure was deployed at the Argonne Leadership Computing Facility (ALCF) and the National Energy Research Scientific Computing Center (NERSC). The testbed was designed to be flexible and capable enough to explore a variety of computing models and hardware design points in order to understand the impact for various scientific applications. During the project, the testbed also served as a valuable resource to application scientists. Applications from a diverse set of projects such as MG-RAST (a metagenomics analysis server), the Joint Genome Institute, the STAR experiment at the Relativistic Heavy Ion Collider, and the Laser Interferometer Gravitational Wave Observatory (LIGO), were used by the Magellan project for benchmarking within the cloud, but the project teams were also able to accomplish important production science utilizing the Magellan cloud resources.

  5. Magellan at NERSC Progress Report for June 2010

    SciTech Connect (OSTI)

    Canon, R. Shane; Broughton, Jeff; Draney, Brent; Jackson, Keith

    2010-06-30

    The Magellan Project was funded by the American Recovery and Reinvestment Act to investigate the applicability of cloud computing for the Department of Energy's Office of Science (DOE-SC). This report covers the progress for the Magellan Project at NERSC since it began in September 2009and focuses on the research aspects of the project.

  6. OGLE-ing the Magellanic system: stellar populations in the Magellanic Bridge

    SciTech Connect (OSTI)

    Skowron, D. M.; Jacyszyn, A. M.; Udalski, A.; Szymański, M. K.; Skowron, J.; Poleski, R.; Kozłowski, S.; Kubiak, M.; Pietrzyński, G.; Soszyński, I.; Mróz, P.; Pietrukowicz, P.; Ulaczyk, K.; Wyrzykowski, Ł.

    2014-11-10

    We report the discovery of a young stellar bridge that forms a continuous connection between the Magellanic Clouds. This finding is based on number density maps for stellar populations found in data gathered by OGLE-IV that fully cover over 270 deg{sup 2} of the sky in the Magellanic Bridge area. This is the most extensive optical survey of this region to date. We find that the young population is present mainly in the western half of the MBR, which, together with the newly discovered young population in the eastern Bridge, form a continuous stream of stars connecting both galaxies along δ ∼ –73.5 deg. The young population distribution is clumped, with one of the major densities close to the SMC and the other fairly isolated and located approximately mid-way between the Clouds, which we call the OGLE island. These overdensities are well matched by H I surface density contours, although the newly found young population in the eastern Bridge is offset by ∼2 deg north from the highest H I density contour. We observe a continuity of red clump stars between the Magellanic Clouds which represent an intermediate-age population. Red clump stars are present mainly in the southern and central parts of the Magellanic Bridge, below its gaseous part, and their presence is reflected by a strong deviation from the radial density profiles of the two galaxies. This may indicate either a tidal stream of stars, or that the stellar halos of the two galaxies overlap. On the other hand, we do not observe such an overlap within an intermediate-age population represented by the top of the red giant branch and the asymptotic giant branch stars. We also see only minor mixing of the old populations of the Clouds in the southern part of the Bridge, represented by the lowest part of the red giant branch.

  7. Magellan: experiences from a Science Cloud

    SciTech Connect (OSTI)

    Ramakrishnan, Lavanya; Zbiegel, Piotr; Campbell, Scott; Bradshaw, Rick; Canon, Richard; Coghlan, Susan; Sakrejda, Iwona; Desai, Narayan; Declerck, Tina; Liu, Anping

    2011-02-02

    Cloud resources promise to be an avenue to address new categories of scientific applications including data-intensive science applications, on-demand/surge computing, and applications that require customized software environments. However, there is a limited understanding on how to operate and use clouds for scientific applications. Magellan, a project funded through the Department of Energy?s (DOE) Advanced Scientific Computing Research (ASCR) program, is investigating the use of cloud computing for science at the Argonne Leadership Computing Facility (ALCF) and the National Energy Research Scientific Computing Facility (NERSC). In this paper, we detail the experiences to date at both sites and identify the gaps and open challenges from both a resource provider as well as application perspective.

  8. Magellan Explores Cloud Computing for DOE's Scientific Mission

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Explores Cloud Computing for DOE's Scientific Mission Magellan Explores Cloud Computing for DOE's Scientific Mission March 30, 2011 Cloud Control -This is a picture of the Magellan management and network control racks at NERSC. To test cloud computing for scientific capability, NERSC and the Argonne Leadership Computing Facility (ALCF) installed purpose-built testbeds for running scientific applications on the IBM iDataPlex cluster. (Photo Credit: Roy Kaltschmidt) Cloud computing is gaining

  9. CHEMICAL EVOLUTION OF THE LARGE MAGELLANIC CLOUD

    SciTech Connect (OSTI)

    Bekki, Kenji [ICRAR, M468, University of Western Australia, 35 Stirling Highway, Crawley Western Australia 6009 (Australia); Tsujimoto, Takuji [National Astronomical Observatory of Japan, Mitaka-shi, Tokyo 181-8588 (Japan)

    2012-12-20

    We adopt a new chemical evolution model for the Large Magellanic Cloud (LMC) and thereby investigate its past star formation and chemical enrichment histories. The delay time distribution of Type Ia supernovae recently revealed by Type Ia supernova surveys is incorporated self-consistently into the new model. The principle results are summarized as follows. The present gas mass fraction and stellar metallicity as well as the higher [Ba/Fe] in metal-poor stars at [Fe/H] < -1.5 can be more self-consistently explained by models with steeper initial mass functions. The observed higher [Mg/Fe] ({>=}0.3) at [Fe/H] {approx} -0.6 and higher [Ba/Fe] (>0.5) at [Fe/H] {approx} -0.3 could be due to significantly enhanced star formation about 2 Gyr ago. The observed overall [Ca/Fe]-[Fe/H] relation and remarkably low [Ca/Fe] (< - 0.2) at [Fe/H] > -0.6 are consistent with models with short-delay supernova Ia and with the more efficient loss of Ca possibly caused by an explosion mechanism of Type II supernovae. Although the metallicity distribution functions do not show double peaks in the models with a starburst about 2 Gyr ago, they show characteristic double peaks in the models with double starbursts {approx}200 Myr and {approx}2 Gyr ago. The observed apparent dip of [Fe/H] around {approx}1.5 Gyr ago in the age-metallicity relation can be reproduced by models in which a large amount ({approx}10{sup 9} M{sub Sun }) of metal-poor ([Fe/H] < -1) gas can be accreted onto the LMC.

  10. THE PROPER MOTION OF THE MAGELLANIC CLOUDS. II. NEW RESULTS FOR FIVE SMALL MAGELLANIC CLOUD FIELDS

    SciTech Connect (OSTI)

    Costa, Edgardo; Mendez, Rene A.; Moyano, Maximiliano; Pedreros, Mario H.; Gallart, Carme; Noel, Noelia E-mail: rmendez@das.uchile.cl E-mail: mmoyano@mpia-hd.mpg.de E-mail: carme@iac.es

    2011-04-15

    We present new results from a ground-based program to determine the proper motion of the Magellanic Clouds (MCs) relative to background quasars (QSOs), being carried out with the Irenee du Pont 2.5 m telescope at Las Campanas Observatory, Chile. The data were secured over a time base of seven years and with eight epochs of observation 'As measured' (field) proper motions were obtained for five QSO fields in the Small Magellanic Cloud (SMC): QJ0033-7028, QJ0035-7201, QJ0047-7530, QJ0102-7546, and QJ0111-7249. Assuming that the SMC has a disklike central structure, but that it does not rotate, we determined a center-of-mass (CM) proper motion for the SMC from two of these fields, QJ0033-7028 and QJ0035-7201, located to the northwest and west of the main body of the SMC, respectively. Combining these latter proper motions with the CM proper motion presented by Costa et al. (hereafter CMP09) for the SMC (from the field QJ0036-7227, located to the west of the main body of the SMC), we obtain a weighted mean of {mu}{sub {alpha}} cos {delta} = +0.93 {+-} 0.14 mas yr{sup -1} and {mu}{sub {delta}} = -1.25 {+-} 0.11 mas yr{sup -1}. This CM proper motion is in good agreement with recent results by Piatek et al. and Vieira et al., and we are confident that it is a good representation of the 'bulk' transverse motion of the SMC. On the contrary, the results we obtain from the fields QJ0047-7530 and QJ0102-7546, located to the south of the main body of the SMC, and the field QJ0111-7249, located to the east of its main body, seem to be affected by streaming motions. For this reason, we have not used the latter to determine the SMC CM proper motion. These streaming motions could be evidence that the SMC was tidally disrupted in a close encounter with the Large Magellanic Cloud (LMC). Complementing the SMC CM proper motions given here and in CMP09, with the currently accepted radial velocity of its center, we have derived its galactocentric (gc) velocity components, obtaining a

  11. Talk to the Magellan Staff at SC10 in New Orleans

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Talk to the Magellan Staff at SC10 in New Orleans Talk to the Magellan Staff at SC10 in New Orleans October 12, 2010 Magellan will be highlighted at a variety of workshops and talks at SC10. The Petascale Data Analytics on Clouds Workshop will include talks by Kathy Yelick, Shane Canon, and Nick Wright. On Wednesday, there will be a joint presentation with a collaborators at Argonne in the Argonne booth. That presentation will be followed by a talk in the Berkeley Lab booth (#2448) along with

  12. STAR FORMATION AROUND SUPERGIANT SHELLS IN THE LARGE MAGELLANIC CLOUD

    SciTech Connect (OSTI)

    Book, Laura G.; Chu Youhua; Gruendl, Robert A.; Fukui, Yasuo

    2009-03-15

    We examine the recent star formation associated with four supergiant shells in the Large Magellanic Cloud (LMC): LMC 1, 4, 5, and 6, which have been shown to have simple expanding-shell structures. H II regions and OB associations are used to infer star formation in the last few Myr, while massive young stellar objects reveal the current ongoing star formation. Distributions of ionized H I and molecular components of the interstellar gas are compared with the sites of recent and current star formation to determine whether triggering has taken place. We find that a great majority of the current star formation has occurred in gravitationally unstable regions, and that evidence of triggered star formation is prevalent at both large and local scales.

  13. Utilisation des défibrillateurs

    ScienceCinema (OSTI)

    None

    2011-10-06

    Information faite par le service medical et le service des pompiers sur l'utilisation des defibrillateurs.

  14. The COS/UVES absorption survey of the Magellanic stream. III. Ionization, total mass, and inflow rate onto the Milky Way

    SciTech Connect (OSTI)

    Fox, Andrew J.; Thom, Christopher; Tumlinson, Jason; Ely, Justin; Kumari, Nimisha [Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218 (United States); Wakker, Bart P.; Hernandez, Audra K.; Haffner, L. Matthew [Department of Astronomy, University of Wisconsin-Madison, 475 North Charter Street, Madison, WI 53706 (United States); Barger, Kathleen A.; Lehner, Nicolas; Howk, J. Christopher [Department of Physics, University of Notre Dame, 225 Nieuwland Science Hall, Notre Dame, IN 46556 (United States); Richter, Philipp [Institut fr Physik und Astronomie, Universitt Potsdam, Haus 28, Karl-Liebknecht-Strasse 24/25, D-14476, Potsdam (Germany); Bland-Hawthorn, Joss [Institute of Astronomy, School of Physics, University of Sydney, Sydney, NSW 2006 (Australia); Charlton, Jane C. [Department of Astronomy and Astrophysics, Pennsylvania State University, University Park, PA 16802 (United States); Westmeier, Tobias [ICRAR, The University of Western Australia, 35 Stirling Highway, Crawley, WA 6009 (Australia); Misawa, Toru [School of General Education, Shinshu University, 3-1-1 Asahi, Matsumoto, Nagano 390-8621 (Japan); Rodriguez-Hidalgo, Paola, E-mail: afox@stsci.edu [Department of Physics and Astronomy, York University, 4700 Keele Street, Toronto, ON M3J 1P3 (Canada)

    2014-06-01

    Dynamic interactions between the two Magellanic Clouds have flung large quantities of gas into the halo of the Milky Way. The result is a spectacular arrangement of gaseous structures, including the Magellanic Stream, the Magellanic Bridge, and the Leading Arm (collectively referred to as the Magellanic System). In this third paper of a series studying the Magellanic gas in absorption, we analyze the gas ionization level using a sample of 69 Hubble Space Telescope/Cosmic Origins Spectrograph sightlines that pass through or within 30 of the 21 cm emitting regions. We find that 81% (56/69) of the sightlines show UV absorption at Magellanic velocities, indicating that the total cross-section of the Magellanic System is ?11,000 deg{sup 2}, or around one-quarter of the entire sky. Using observations of the Si III/Si II ratio together with Cloudy photoionization modeling, we calculate the total gas mass (atomic plus ionized) of the Magellanic System to be ?2.0 10{sup 9} M {sub ?} (d/55 kpc){sup 2}, with the ionized gas contributing around three times as much mass as the atomic gas. This is larger than the current-day interstellar H I mass of both Magellanic Clouds combined, indicating that they have lost most of their initial gas mass. If the gas in the Magellanic System survives to reach the Galactic disk over its inflow time of ?0.5-1.0 Gyr, it will represent an average inflow rate of ?3.7-6.7 M {sub ?} yr{sup 1}, potentially raising the Galactic star formation rate. However, multiple signs of an evaporative interaction with the hot Galactic corona indicate that the Magellanic gas may not survive its journey to the disk fully intact and will instead add material to (and cool) the corona.

  15. A modern search for Wolf-Rayet stars in the Magellanic Clouds: First results

    SciTech Connect (OSTI)

    Massey, Philip; Neugent, Kathryn F.; Morrell, Nidia; Hillier, D. John E-mail: kneugent@lowell.edu E-mail: hillier@pitt.edu

    2014-06-10

    Over the years, directed surveys and incidental spectroscopy have identified 12 Wolf-Rayet (WR) stars in the Small Magellanic Cloud (SMC) and 139 in the Large Magellanic Cloud (LMC), numbers which are often described as 'essentially complete'. Yet, new WRs are discovered in the LMC almost yearly. We have therefore initiated a new survey of both Magellanic Clouds using the same interference-filter imaging technique previously applied to M31 and M33. We report on our first observing season, in which we have successfully surveyed ∼15% of our intended area of the SMC and LMC. Spectroscopy has confirmed nine newly found WRs in the LMC (a 6% increase), including one of WO-type, only the third known in that galaxy and the second to be discovered recently. The other eight are WN3 stars that include an absorption component. In two, the absorption is likely from an O-type companion, but the other six are quite unusual. Five would be classified naively as 'WN3+O3 V', but such a pairing is unlikely given the rarity of O3 stars, the short duration of this phase (which is incommensurate with the evolution of a companion to a WN star), and because these stars are considerably fainter than O3 V stars. The sixth star may also fall into this category. CMFGEN modeling suggests these stars are hot, bolometrically luminous, and N-rich like other WN3 stars, but lack the strong winds that characterize WNs. Finally, we discuss two rare Of?p stars and four Of supergiants we found, and propose that the B[e] star HD 38489 may have a WN companion.

  16. THE PERIOD-LUMINOSITY RELATION OF RED SUPERGIANT STARS IN THE SMALL MAGELLANIC CLOUD

    SciTech Connect (OSTI)

    Yang Ming; Jiang, B. W. E-mail: bjiang@bnu.edu.cn

    2012-07-20

    The characteristics of light variation of red supergiant (RSG) stars in the Small Magellanic Cloud (SMC) are analyzed based on the nearly 8-10 year data collected by the ASAS and MACHO projects. The 126 identified RSGs are classified into five categories accordingly: 20 with poor photometry, 55 with no reliable period, 6 with semi-regular variation, 15 with a long secondary period (LSP) and distinguishable short period, and 30 with only an LSP. For the semi-regular variables and the LSP variables with distinguishable short period, the K{sub S} -band period-luminosity (P-L) relation is analyzed and compared with that of the Galaxy, the Large Magellanic Cloud, and M33. It is found that the RSGs in these galaxies obey a similar P-L relation except for those in the Galaxy. In addition, the P-L relations in the infrared bands, namely, the 2MASS JHK{sub S} , Spitzer/IRAC, and Spitzer/MIPS 24 {mu}m bands, are derived with high reliability. The best P-L relation occurs in the Spitzer/IRAC [3.6] and [4.5] bands. Based on the comparison with the theoretical calculation of the P-L relation, the mode of pulsation of RSGs in the SMC is suggested to be the first-overtone radial mode.

  17. MAGNETIC FIELD STRUCTURE OF THE LARGE MAGELLANIC CLOUD FROM FARADAY ROTATION MEASURES OF DIFFUSE POLARIZED EMISSION

    SciTech Connect (OSTI)

    Mao, S. A.; McClure-Griffiths, N. M.; McConnell, D.; Gaensler, B. M.; Haverkorn, M.; Beck, R.; Wolleben, M.; Stanimirovic, S.; Dickey, J. M.; Staveley-Smith, L.

    2012-11-01

    We present a study of the magnetic field of the Large Magellanic Cloud (LMC), carried out using diffuse polarized synchrotron emission data at 1.4 GHz acquired at the Parkes Radio Telescope and the Australia Telescope Compact Array. The observed diffuse polarized emission is likely to originate above the LMC disk on the near side of the galaxy. Consistent negative rotation measures (RMs) derived from the diffuse emission indicate that the line-of-sight magnetic field in the LMC's near-side halo is directed coherently away from us. In combination with RMs of extragalactic sources that lie behind the galaxy, we show that the LMC's large-scale magnetic field is likely to be of quadrupolar geometry, consistent with the prediction of dynamo theory. On smaller scales, we identify two brightly polarized filaments southeast of the LMC, associated with neutral hydrogen arms. The filaments' magnetic field potentially aligns with the direction toward the Small Magellanic Cloud (SMC). We suggest that tidal interactions between the SMC and the LMC in the past 10{sup 9} years are likely to have shaped the magnetic field in these filaments.

  18. The Araucaria project. The distance to the small Magellanic Cloud from late-type eclipsing binaries

    SciTech Connect (OSTI)

    Graczyk, Dariusz; Pietrzyński, Grzegorz; Gieren, Wolfgang; Pilecki, Bogumił; Villanova, Sandro; Gallenne, Alexandre; Thompson, Ian B.; Konorski, Piotr; Udalski, Andrzej; Soszyński, Igor; Górski, Marek; Suchomska, Ksenia; Karczmarek, Paulina; Kudritzki, Rolf-Peter; Bresolin, Fabio

    2014-01-01

    We present a distance determination to the Small Magellanic Cloud (SMC) based on an analysis of four detached, long-period, late-type eclipsing binaries discovered by the Optical Gravitational Lensing Experiment (OGLE) survey. The components of the binaries show negligible intrinsic variability. A consistent set of stellar parameters was derived with low statistical and systematic uncertainty. The absolute dimensions of the stars are calculated with a precision of better than 3%. The surface brightness-infrared color relation was used to derive the distance to each binary. The four systems clump around a distance modulus of (m – M) = 18.99 with a dispersion of only 0.05 mag. Combining these results with the distance published by Graczyk et al. for the eclipsing binary OGLE SMC113.3 4007, we obtain a mean distance modulus to the SMC of 18.965 ± 0.025 (stat.) ± 0.048 (syst.) mag. This corresponds to a distance of 62.1 ± 1.9 kpc, where the error includes both uncertainties. Taking into account other recent published determinations of the SMC distance we calculated the distance modulus difference between the SMC and the Large Magellanic Cloud equal to 0.458 ± 0.068 mag. Finally, we advocate μ{sub SMC} = 18.95 ± 0.07 as a new 'canonical' value of the distance modulus to this galaxy.

  19. CHEMICAL SIGNATURE OF A MAJOR MERGER IN THE EARLY FORMATION OF THE SMALL MAGELLANIC CLOUD

    SciTech Connect (OSTI)

    Tsujimoto, Takuji [National Astronomical Observatory, Mitaka-shi, Tokyo 181-8588 (Japan); Bekki, Kenji [School of Physics, University of New South Wales, Sydney 2052, NSW (Australia)], E-mail: taku.tsujimoto@nao.ac.jp

    2009-08-01

    The formation history of the Small Magellanic Cloud (SMC) is unraveled based on the results of our new chemical evolution models constructed for the SMC, highlighting the observed anomaly in the age-metallicity relation for star clusters in the SMC. We first propose that evidence of a major merger is imprinted in the age-metallicity relation as a dip in [Fe/H]. Our models predict that the major merger with a mass ratio of 1:1 to 1:4 occurred at {approx}7.5 Gyr ago, with a good reproduction of the abundance distribution function of field stars in the SMC. Furthermore, our models predict a relatively large scatter in [Mg/Fe] for -1.4 {<=} [Fe/H] {<=} -1.1 as a reflection of a looping feature resulting from the temporally inverse progress of chemical enrichment, which can be tested against future observational results. Given that the observed velocity dispersion ({approx}30 km s{sup -1}) of the SMC is much smaller than that ({approx}160 km s{sup -1}) of the Galactic halo, our finding strongly implies that the predicted merger event happened in a small group environment that was far from the Galaxy and contained a number of small gas-rich dwarfs comparable to the SMC. This theoretical view is extensively discussed in the framework that considers a connection with the formation history of the Large Magellanic Cloud.

  20. NASEO Midwest Regional Meeting

    Broader source: Energy.gov [DOE]

    The National Association of State Energy Officials (NASEO) is hosting its Midwest Regional Meeting in Des Moines, Iowa.

  1. PROPER-MOTION STUDY OF THE MAGELLANIC CLOUDS USING SPM MATERIAL

    SciTech Connect (OSTI)

    Vieira, Katherine; Girard, Terrence M.; Van Altena, William F.; Casetti-Dinescu, Dana I.; Korchagin, Vladimir I.; Herrera, David, E-mail: kvieira@cida.v, E-mail: terry.girard@yale.ed, E-mail: william.vanaltena@yale.ed [Astronomy Department, Yale University, P.O. Box 208101, New Haven, CT 06520 (United States)

    2010-12-15

    Absolute proper motions are determined for stars and galaxies to V = 17.5 over a 450 deg{sup 2} area that encloses both Magellanic Clouds. The proper motions are based on photographic and CCD observations of the Yale/San Juan Southern Proper Motion program, which span a baseline of 40 years. Multiple, local relative proper-motion measures are combined in an overlap solution using photometrically selected Galactic disk stars to define a global relative system that is then transformed to absolute using external galaxies and Hipparcos stars to tie into the ICRS. The resulting catalog of 1.4 million objects is used to derive the mean absolute proper motions of the Large Magellanic Cloud (LMC) and the Small Magellanic Cloud (SMC); ({mu}{sub {alpha}}cos {delta}, {mu}{sub {delta}}){sub LMC} = (1.89, + 0.39) {+-} (0.27, 0.27) masyr{sup -1} and ({mu}{sub {alpha}}cos {delta}, {mu}{sub {delta}}){sub SMC} = (0.98, - 1.01) {+-} (0.30, 0.29) masyr{sup -1}. These mean motions are based on best-measured samples of 3822 LMC stars and 964 SMC stars. A dominant portion (0.25 mas yr{sup -1}) of the formal errors is due to the estimated uncertainty in the inertial system of the Hipparcos Catalog stars used to anchor the bright end of our proper motion measures. A more precise determination can be made for the proper motion of the SMC relative to the LMC; ({mu}{sub {alpha}cos {delta}}, {mu}{sub {delta}}){sub SMC-LMC} = (-0.91, - 1.49) {+-} (0.16, 0.15) masyr{sup -1}. This differential value is combined with measurements of the proper motion of the LMC taken from the literature to produce new absolute proper-motion determinations for the SMC, as well as an estimate of the total velocity difference of the two clouds to within {+-}54 km s{sup -1}. The absolute proper-motion results are consistent with the Clouds' orbits being marginally bound to the Milky Way, albeit on an elongated orbit. The inferred relative velocity between the Clouds places them near their binding energy limit and

  2. THE SUBMILLIMETER AND MILLIMETER EXCESS OF THE SMALL MAGELLANIC CLOUD: MAGNETIC DIPOLE EMISSION FROM MAGNETIC NANOPARTICLES?

    SciTech Connect (OSTI)

    Draine, B. T.; Hensley, Brandon

    2012-09-20

    The Small Magellanic Cloud (SMC) has surprisingly strong submillimeter- and millimeter-wavelength emission that is inconsistent with standard dust models, including those with emission from spinning dust. Here, we show that the emission from the SMC may be understood if the interstellar dust mixture includes magnetic nanoparticles, emitting magnetic dipole radiation resulting from thermal fluctuations in the magnetization. The magnetic grains can be metallic iron, magnetite Fe{sub 3}O{sub 4}, or maghemite {gamma}-Fe{sub 2}O{sub 3}. The required mass of iron is consistent with elemental abundance constraints. The magnetic dipole emission is predicted to be polarized orthogonally to the normal electric dipole radiation if the nanoparticles are inclusions in larger grains. We speculate that other low-metallicity galaxies may also have a large fraction of the interstellar Fe in magnetic materials.

  3. Detection of water masers toward young stellar objects in the Large Magellanic Cloud

    SciTech Connect (OSTI)

    Johanson, A. K.; Migenes, V.; Breen, S. L.

    2014-02-01

    We present results from a search for water maser emission toward N4A, N190, and N206, three regions of massive star formation in the Large Magellanic Cloud (LMC). Four water masers were detected; two toward N4A, and two toward N190. In the latter region, no previously known maser emission has been reported. Future studies of maser proper motion to determine the galactic dynamics of the LMC will benefit from the independent data points the new masers in N190 provide. Two of these masers are associated with previously identified massive young stellar objects (YSOs), which strongly supports the authenticity of the classification. We argue that the other two masers identify previously unknown YSOs. No masers were detected toward N206, but it does host a newly discovered 22 GHz continuum source, also associated with a massive YSO. We suggest that future surveys for water maser emission in the LMC be targeted toward the more luminous, massive YSOs.

  4. ORIGIN OF THE UNUSUALLY LOW NITROGEN ABUNDANCES IN YOUNG POPULATIONS OF THE LARGE MAGELLANIC CLOUD

    SciTech Connect (OSTI)

    Bekki, Kenji [ICRAR, M468, University of Western Australia, 35 Stirling Highway, Crawley Western Australia 6009 (Australia); Tsujimoto, Takuji [National Astronomical Observatory, Mitaka-shi, Tokyo 181-8588 (Japan)

    2010-10-01

    It is a longstanding problem that H II regions and very young stellar populations in the Large Magellanic Cloud (LMC) have nitrogen abundances ([N/H]) that are a factor of {approx}7 lower than the solar value. We here discuss a new scenario in which the observed unusually low nitrogen abundances can be closely associated with recent collisions and subsequent accretion of H I high velocity clouds (HVCs) that surround the Galaxy and have low nitrogen abundances. We show that if the observed low [N/H] is limited to very young stars with ages less than {approx}10{sup 7} yr, then the collision/accretion rate of the HVCs onto the LMC needs to be {approx}0.2 M{sub sun} yr{sup -1} (corresponding to the total HVC mass of 10{sup 6}-10{sup 7} M{sub sun}) to dilute the original interstellar medium (ISM) before star formation. The required accretion rate means that even if the typical mass of HVCs accreted onto the LMC is {approx}10{sup 7} M{sub sun}, the Galaxy needs to have {approx}2500 massive HVCs within the LMC's orbital radius with respect to the Galactic center. The rather large number of required massive HVCs drives us to suggest that the HVCs are not likely to efficiently dilute the ISM of the LMC and consequently lower the [N/H]. We thus suggest the transfer of gas with low [N/H] from the Small Magellanic Cloud to the LMC as a promising scenario that can explain the observed low [N/H].

  5. NEW TESTS FOR DISRUPTION MECHANISMS OF STAR CLUSTERS: THE LARGE AND SMALL MAGELLANIC CLOUDS

    SciTech Connect (OSTI)

    Chandar, Rupali; Fall, S. Michael; Whitmore, Bradley C. E-mail: fall@stsci.ed

    2010-03-10

    We compare the observed bivariate distribution of masses (M) and ages (tau) of star clusters in the Large Magellanic Cloud (LMC) with the predicted distributions g(M, tau) from three idealized models for the disruption of star clusters: (1) sudden mass-dependent disruption, (2) gradual mass-dependent disruption, and (3) gradual mass-independent disruption. The model with mass-independent disruption provides a good, first-order description of these cluster populations, with g(M, tau) {proportional_to} M {sup beta}tau{sup g}amma, beta = -1.8 +- 0.2 and gamma = -0.8 +- 0.2, at least for clusters with ages tau {approx}< 10{sup 9} yr and masses M {approx}> 10{sup 3} M{sub sun} (more specifically, tau {approx}< 10{sup 7}(M/10{sup 2} M{sub sun}){sup 1.3} yr). This model predicts that the clusters should have a power-law luminosity function, dN/dL {proportional_to} L {sup -1.8}, in agreement with observations. The first two models, on the other hand, fare poorly when describing the observations, refuting previous claims that mass-dependent disruption of star clusters is observed in the LMC over the studied M-tau domain. Clusters in the SMC can be described by the same g(M, tau) distribution as for the LMC, but with smaller samples and hence larger uncertainties. The successful g(M, tau) model for clusters in the Magellanic Clouds is virtually the same as the one for clusters in the merging Antennae galaxies, but extends the domain of validity to lower masses and to older ages. This indicates that the dominant disruption processes are similar in these very different galaxies over at least tau {approx}< 10{sup 8} yr and possibly tau {approx}< 10{sup 9} yr. The mass functions for young clusters in the LMC are power laws, while that for ancient globular clusters is peaked. We show that the observed shapes of these mass functions are consistent with expectations from the simple evaporation model presented by McLaughlin and Fall.

  6. Financiere des Energies | Open Energy Information

    Open Energy Info (EERE)

    Jump to: navigation, search Name: Financiere des Energies Place: Saint Contest, France Zip: 14280 Product: Prospects for new production sites and looks for the best...

  7. HFPK 334: An unusual supernova remnant in the Small Magellanic Cloud

    SciTech Connect (OSTI)

    Crawford, E. J.; Filipović, M. D.; McEntaffer, R. L.; Brantseg, T.; Heitritter, K.; Roper, Q.; Haberl, F.; Urošević, D.

    2014-11-01

    We present new Australia Telescope Compact Array radio-continuum and XMM-Newton/Chandra X-ray Observatory observations of the unusual supernova remnant (SNR) HFPK 334 in the Small Magellanic Cloud (SMC). The remnant follows a shell-type morphology in the radio continuum and has a size of ∼20 pc at the SMC distance. The X-ray morphology is similar; however, we detect a prominent point source close to the center of the SNR exhibiting a spectrum with a best-fit power law with a photon index of Γ = 2.7 ± 0.5. This central point source is most likely a background object and cannot be directly associated with the remnant. The high temperature, nonequilibrium conditions in the diffuse region suggest that this gas has been recently shocked and points toward a younger SNR with an age of ≲ 1800 yr. With an average radio spectral index of α = –0.59 ± 0.09, we find that an equipartition magnetic field for the remnant is ∼90 μG, a value typical of younger SNRs in low-density environments. Also, we report the detection of scattered radio polarization across the remnant at 20 cm, with a peak fractional polarization level of 25% ± 5%.

  8. SUPERGIANT SHELLS AND MOLECULAR CLOUD FORMATION IN THE LARGE MAGELLANIC CLOUD

    SciTech Connect (OSTI)

    Dawson, J. R.; Dickey, John M.; McClure-Griffiths, N. M.; Wong, T.; Hughes, A.; Fukui, Y.; Kawamura, A.

    2013-01-20

    We investigate the influence of large-scale stellar feedback on the formation of molecular clouds in the Large Magellanic Cloud (LMC). Examining the relationship between H I and {sup 12}CO(J = 1-0) in supergiant shells (SGSs), we find that the molecular fraction in the total volume occupied by SGSs is not enhanced with respect to the rest of the LMC disk. However, the majority of objects ({approx}70% by mass) are more molecular than their local surroundings, implying that the presence of a supergiant shell does on average have a positive effect on the molecular gas fraction. Averaged over the full SGS sample, our results suggest that {approx}12%-25% of the molecular mass in supergiant shell systems was formed as a direct result of the stellar feedback that created the shells. This corresponds to {approx}4%-11% of the total molecular mass of the galaxy. These figures are an approximate lower limit to the total contribution of stellar feedback to molecular cloud formation in the LMC, and constitute one of the first quantitative measurements of feedback-triggered molecular cloud formation in a galactic system.

  9. DETECTION OF AN ULTRA-BRIGHT SUBMILLIMETER GALAXY BEHIND THE SMALL MAGELLANIC CLOUD

    SciTech Connect (OSTI)

    Takekoshi, Tatsuya; Minamidani, Tetsuhiro; Sorai, Kazuo; Habe, Asao; Tamura, Yoichi; Kohno, Kotaro; Oogi, Taira; Ezawa, Hajime; Komugi, Shinya; Mizuno, Norikazu; Muller, Erik; Kawamura, Akiko; Oshima, Tai; Scott, Kimberly S.; Austermann, Jason E.; Tosaki, Tomoka; Onishi, Toshikazu; Fukui, Yasuo; Matsuo, Hiroshi; Aretxaga, Itziar; and others

    2013-09-10

    We report the discovery of a new ultra-bright submillimeter galaxy (SMG) behind the Small Magellanic Cloud (SMC). This SMG is detected as a 43.3 {+-} 8.4 mJy point source (MM J01071-7302, hereafter MMJ0107) in the 1.1 mm continuum survey of the SMC by AzTEC on the ASTE telescope. MMJ0107 is also detected in the radio (843 MHz), Herschel/SPIRE, Spitzer MIPS 24 {mu}m, all IRAC bands, Wide-field Infrared Survey Explorer, and near-infrared (J, H, K{sub S} ). We find an optical (U, B, V) source, which might be the lensing object, at a distance of 1.''4 from near-infrared and IRAC sources. Photometric redshift estimates for the SMG using representative spectral energy distribution templates show the redshifts of 1.4-3.9. We estimate total far-infrared luminosity of (0.3-2.2) Multiplication-Sign 10{sup 14} {mu}{sup -1} L{sub Sun} and a star formation rate of 5600-39, 000 {mu}{sup -1} M{sub Sun} yr{sup -1}, where {mu} is the gravitational magnification factor. This apparent extreme star formation activity is likely explained by a highly magnified gravitational lens system.

  10. Radial velocity curves of ellipsoidal red giant binaries in the Large Magellanic Cloud

    SciTech Connect (OSTI)

    Nie, J. D.; Wood, P. R. E-mail: peter.wood@anu.edu.au

    2014-12-01

    Ellipsoidal red giant binaries are close binary systems where an unseen, relatively close companion distorts the red giant, leading to light variations as the red giant moves around its orbit. These binaries are likely to be the immediate evolutionary precursors of close binary planetary nebula and post-asymptotic giant branch and post-red giant branch stars. Due to the MACHO and OGLE photometric monitoring projects, the light variability nature of these ellipsoidal variables has been well studied. However, due to the lack of radial velocity curves, the nature of their masses, separations, and other orbital details has so far remained largely unknown. In order to improve this situation, we have carried out spectral monitoring observations of a large sample of 80 ellipsoidal variables in the Large Magellanic Cloud and we have derived radial velocity curves. At least 12 radial velocity points with good quality were obtained for most of the ellipsoidal variables. The radial velocity data are provided with this paper. Combining the photometric and radial velocity data, we present some statistical results related to the binary properties of these ellipsoidal variables.

  11. The Mass Distribution and Assembly of the Milky Way from the Properties of the Magellanic Clouds

    SciTech Connect (OSTI)

    Busha, Michael T.; Marshall, Philip J.; Wechsler, Risa H.; Klypin, Anatoly; Primack, Joel; /UC, Santa Cruz, Phys. Dept.

    2012-02-29

    We present a new measurement of the mass of the Milky Way (MW) based on observed properties of its largest satellite galaxies, the Magellanic Clouds (MCs), and an assumed prior of a {Lambda}CDM universe. The large, high-resolution Bolshoi cosmological simulation of this universe provides a means to statistically sample the dynamical properties of bright satellite galaxies in a large population of dark matter halos. The observed properties of the MCs, including their circular velocity, distance from the center of the MW, and velocity within the MW halo, are used to evaluate the likelihood that a given halo would have each or all of these properties; the posterior probability distribution function (PDF) for any property of the MW system can thus be constructed. This method provides a constraint on the MW virial mass, 1.2{sup +0.7} - {sub 0.4}(stat.){sup +0.3} - {sub 0.3}(sys.) x 10{sup 12} M {circle_dot} (68% confidence), which is consistent with recent determinations that involve very different assumptions. In addition, we calculate the posterior PDF for the density profile of the MW and its satellite accretion history. Although typical satellites of 10{sup 12} M {circle_dot} halos are accreted over a wide range of epochs over the last 10 Gyr, we find a {approx}72% probability that the MCs were accreted within the last Gyr, and a 50% probability that they were accreted together.

  12. Deep Washington photometry of inconspicuous star cluster candidates in the Large Magellanic Cloud

    SciTech Connect (OSTI)

    Choudhury, Samyaday; Subramaniam, Annapurni; Piatti, Andrés E.

    2015-02-01

    We present deep Washington photometry of 45 poorly populated star cluster candidates in the Large Magellanic Cloud (LMC). We have performed a systematic study to estimate the parameters of the cluster candidates by matching theoretical isochrones to the cleaned and dereddened cluster color–magnitude diagrams. We were able to estimate the basic parameters for 33 clusters, out of which 23 are identified as single clusters and 10 are found to be members of double clusters. The other 12 cluster candidates have been classified as possible clusters/asterisms. About 50% of the true clusters are in the 100–300 Myr age range, whereas some are older or younger. We have discussed the distribution of age, location, and reddening with respect to field, as well as the size of true clusters. The sizes and masses of the studied sample are found to be similar to that of open clusters in the Milky Way. Our study adds to the lower end of cluster mass distribution in the LMC, suggesting that the LMC, apart from hosting rich clusters, also has formed small, less massive open clusters in the 100–300 Myr age range.

  13. ON THE DISTANCE OF THE MAGELLANIC CLOUDS USING CEPHEID NIR AND OPTICAL-NIR PERIOD-WESENHEIT RELATIONS

    SciTech Connect (OSTI)

    Inno, L.; Bono, G.; Buonanno, R.; Genovali, K.; Matsunaga, N.; Caputo, F.; Laney, C. D.; Marconi, M.; Piersimoni, A. M.; Primas, F.; Romaniello, M.

    2013-02-10

    We present the largest near-infrared (NIR) data sets, JHKs, ever collected for classical Cepheids in the Magellanic Clouds (MCs). We selected fundamental (FU) and first overtone (FO) pulsators, and found 4150 (2571 FU, 1579 FO) Cepheids for Small Magellanic Cloud (SMC) and 3042 (1840 FU, 1202 FO) for Large Magellanic Cloud (LMC). Current sample is 2-3 times larger than any sample used in previous investigations with NIR photometry. We also discuss optical VI photometry from OGLE-III. NIR and optical-NIR Period-Wesenheit (PW) relations are linear over the entire period range (0.0 < log P {sub FU} {<=} 1.65) and their slopes are, within the intrinsic dispersions, common between the MCs. These are consistent with recent results from pulsation models and observations suggesting that the PW relations are minimally affected by the metal content. The new FU and FO PW relations were calibrated using a sample of Galactic Cepheids with distances based on trigonometric parallaxes and Cepheid pulsation models. By using FU Cepheids we found a true distance moduli of 18.45 {+-} 0.02(random) {+-} 0.10(systematic) mag (LMC) and 18.93 {+-} 0.02(random) {+-} 0.10(systematic) mag (SMC). These estimates are the weighted mean over 10 PW relations and the systematic errors account for uncertainties in the zero point and in the reddening law. We found similar distances using FO Cepheids (18.60 {+-} 0.03(random) {+-} 0.10(systematic) mag (LMC) and 19.12 {+-} 0.03(random) {+-} 0.10(systematic) mag (SMC)). These new MC distances lead to the relative distance, {Delta}{mu} = 0.48 {+-} 0.03 mag (FU, log P = 1) and {Delta}{mu} = 0.52 {+-} 0.03 mag (FO, log P = 0.5), which agrees quite well with previous estimates based on robust distance indicators.

  14. HERschel key program heritage: A far-infrared source catalog for the Magellanic Clouds

    SciTech Connect (OSTI)

    Seale, Jonathan P.; Meixner, Margaret; Sewiło, Marta; Babler, Brian; Engelbracht, Charles W.; Misselt, Karl; Montiel, Edward; Gordon, Karl; Roman-Duval, Julia; Hony, Sacha; Okumura, Koryo; Panuzzo, Pasquale; Sauvage, Marc; Chen, C.-H. Rosie; Indebetouw, Remy; Matsuura, Mikako; Oliveira, Joana M.; Loon, Jacco Th. van; Srinivasan, Sundar; and others

    2014-12-01

    Observations from the HERschel Inventory of the Agents of Galaxy Evolution (HERITAGE) have been used to identify dusty populations of sources in the Large and Small Magellanic Clouds (LMC and SMC). We conducted the study using the HERITAGE catalogs of point sources available from the Herschel Science Center from both the Photodetector Array Camera and Spectrometer (PACS; 100 and 160 μm) and Spectral and Photometric Imaging Receiver (SPIRE; 250, 350, and 500 μm) cameras. These catalogs are matched to each other to create a Herschel band-merged catalog and then further matched to archival Spitzer IRAC and MIPS catalogs from the Spitzer Surveying the Agents of Galaxy Evolution (SAGE) and SAGE-SMC surveys to create single mid- to far-infrared (far-IR) point source catalogs that span the wavelength range from 3.6 to 500 μm. There are 35,322 unique sources in the LMC and 7503 in the SMC. To be bright in the FIR, a source must be very dusty, and so the sources in the HERITAGE catalogs represent the dustiest populations of sources. The brightest HERITAGE sources are dominated by young stellar objects (YSOs), and the dimmest by background galaxies. We identify the sources most likely to be background galaxies by first considering their morphology (distant galaxies are point-like at the resolution of Herschel) and then comparing the flux distribution to that of the Herschel Astrophysical Terahertz Large Area Survey (ATLAS) survey of galaxies. We find a total of 9745 background galaxy candidates in the LMC HERITAGE images and 5111 in the SMC images, in agreement with the number predicted by extrapolating from the ATLAS flux distribution. The majority of the Magellanic Cloud-residing sources are either very young, embedded forming stars or dusty clumps of the interstellar medium. Using the presence of 24 μm emission as a tracer of star formation, we identify 3518 YSO candidates in the LMC and 663 in the SMC. There are far fewer far-IR bright YSOs in the SMC than the LMC

  15. A survey of infrared supernova remnants in the Large Magellanic Cloud

    SciTech Connect (OSTI)

    Seok, Ji Yeon; Koo, Bon-Chul; Onaka, Takashi

    2013-12-20

    We present a comprehensive infrared study of supernova remnants (SNRs) in the Large Magellanic Cloud (LMC) using near- to mid-infrared images taken by Infrared Array Camera (IRAC; 3.6, 4.5, 5.8, and 8 μm) and Multiband Imaging Photometer (MIPS; 24 and 70 μm) onboard the Spitzer Space Telescope. Among the 47 bona fide LMC SNRs, 29 were detected in infrared, giving a high detection rate of 62%. All 29 SNRs show emission at 24 μm, and 20 out of 29 show emission in one or several IRAC bands. We present their 4.5, 8, 24, and 70 μm images and a table summarizing their Spitzer fluxes. We find that the LMC SNRs are considerably fainter than the Galactic SNRs, and that, among the LMC SNRs, Type Ia SNRs are significantly fainter than core-collapse SNRs. We conclude that the MIPS emission of essentially all SNRs originates from dust emission, whereas their IRAC emissions originate from ionic/molecular lines, polycyclic aromatic hydrocarbons emission, or synchrotron emission. The infrared fluxes show correlation with radio and X-ray fluxes. For SNRs that have similar morphology in infrared and X-rays, the ratios of 24 to 70 μm fluxes have good correlation with the electron density of hot plasma. The overall correlation is explained well by the emission from collisionally heated silicate grains of 0.1 μm size, but for mature SNRs with relatively low gas temperatures, the smaller-sized grain population is favored more. For those that appear different between infrared and X-rays, the emission in the MIPS bands is probably from dust heated by shock radiation.

  16. A RARE EARLY-TYPE STAR REVEALED IN THE WING OF THE SMALL MAGELLANIC CLOUD

    SciTech Connect (OSTI)

    Evans, C. J.; Hainich, R.; Oskinova, L. M.; Hamann, W.-R.; Todt, H.; Gallagher III, J. S.; Chu, Y.-H.; Gruendl, R. A.; Henault-Brunet, V.

    2012-07-10

    Sk 183 is the visually brightest star in the N90 nebula, a young star-forming region in the Wing of the Small Magellanic Cloud (SMC). We present new optical spectroscopy from the Very Large Telescope which reveals Sk 183 to be one of the most massive O-type stars in the SMC. Classified as an O3-type dwarf on the basis of its nitrogen spectrum, the star also displays broadened He I absorption, which suggests a later type. We propose that Sk 183 has a composite spectrum and that it is similar to another star in the SMC, MPG 324. This brings the number of rare O2- and O3-type stars known in the whole of the SMC to a mere four. We estimate physical parameters for Sk 183 from analysis of its spectrum. For a single-star model, we estimate an effective temperature of 46 {+-} 2 kK, a low mass-loss rate of {approx}10{sup -7} M{sub Sun} yr{sup -1}, and a spectroscopic mass of 46{sup +9}{sub -8} M{sub Sun} (for an adopted distance modulus of 18.7 mag to the young population in the SMC Wing). An illustrative binary model requires a slightly hotter temperature ({approx}47.5 kK) for the primary component. In either scenario, Sk 183 is the earliest-type star known in N90 and will therefore be the dominant source of hydrogen-ionizing photons. This suggests Sk 183 is the primary influence on the star formation along the inner edge of the nebula.

  17. THE COS-HALOS SURVEY: KECK LRIS AND MAGELLAN MagE OPTICAL SPECTROSCOPY

    SciTech Connect (OSTI)

    Werk, Jessica K.; Prochaska, J. Xavier [UCO/Lick Observatory, University of California, Santa Cruz, CA (United States); Thom, Christopher; Tumlinson, Jason [Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD (United States); Tripp, Todd M.; Meiring, Joseph D. [Department of Astronomy, University of Massachusetts, Amherst, MA (United States); O'Meara, John M., E-mail: jwerk@ucolick.org [Department of Chemistry and Physics, Saint Michael's College, Colchester, VT (United States)

    2012-01-01

    We present high signal-to-noise optical spectra for 67 low-redshift (0.1 < z < 0.4) galaxies that lie within close projected distances (5 kpc < {rho} < 150 kpc) of 38 background UV-bright QSOs. The Keck LRIS and Magellan MagE data presented here are part of a survey that aims to construct a statistically sampled map of the physical state and metallicity of gaseous galaxy halos using the Cosmic Origins Spectrograph (COS) on the Hubble Space Telescope. We provide a detailed description of the optical data reduction and subsequent spectral analysis that allow us to derive the physical properties of this uniquely data-rich sample of galaxies. The galaxy sample is divided into 38 pre-selected L {approx} L*, z {approx} 0.2 'target' galaxies and 29 'bonus' galaxies that lie in close proximity to the QSO sightlines. We report galaxy spectroscopic redshifts accurate to {+-}30 km s{sup -1}, impact parameters, rest-frame colors, stellar masses, total star formation rates (SFRs), and gas-phase interstellar medium oxygen abundances. When we compare the distribution of these galaxy characteristics to those of the general low-redshift population, we find good agreement. The L {approx} L* galaxies in this sample span a diverse range of color (1.0 < u - r < 3.0), stellar mass (10{sup 9.5} < M/M{sub Sun} < 10{sup 11.5}), and SFRs (0.01-20 M{sub Sun} yr{sup -1}). These optical data, along with the COS UV spectroscopy, comprise the backbone of our efforts to understand how halo gas properties may correlate with their host galaxy properties, and ultimately to uncover the processes that drive gas outflow and/or are influenced by gas inflow.

  18. Dense molecular clumps associated with the Large Magellanic Cloud supergiant shells LMC 4 and LMC 5

    SciTech Connect (OSTI)

    Fujii, Kosuke; Mizuno, Norikazu [Department of Astronomy, School of Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 133-0033 (Japan); Minamidani, Tetsuhiro [Nobeyama Radio Observatory, 462-2 Nobeyama Minamimaki-mura, Minamisaku-gun, Nagano 384-1305 (Japan); Onishi, Toshikazu; Muraoka, Kazuyuki [Department of Physical Science, Osaka Prefecture University, Gakuen 1-1, Sakai, Osaka 599-8531 (Japan); Kawamura, Akiko; Muller, Erik; Tatematsu, Ken'ichi; Hasegawa, Tetsuo; Miura, Rie E.; Ezawa, Hajime [National Astronomical Observatory of Japan, 2-21-1 Osawa, Mitaka, Tokyo 181-8588 (Japan); Dawson, Joanne [Australia Telescope National Facility, CSIRO Astronomy and Space Science, P.O. Box 76, Epping, NSW 1710 (Australia); Tosaki, Tomoka [Joetsu University of Education, Yamayashiki-machi, Joetsu, Niigata 943-8512 (Japan); Sakai, Takeshi [Graduate School of Informatics and Engineering, The University of Electro-Communications, Chofu, Tokyo 182-8585 (Japan); Tsukagoshi, Takashi [College of Science, Ibaraki University, Bunkyo 2-1-1, Mito 310-8512 (Japan); Tanaka, Kunihiko [Department of Physics, Faculty of Science and Technology, Keio University, 3-14-1 Hiyoshi, Yokohama, Kanagawa 223-8522 (Japan); Fukui, Yasuo, E-mail: kosuke.fujii@nao.ac.jp [Department of Astrophysics, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8602 (Japan)

    2014-12-01

    We investigate the effects of supergiant shells (SGSs) and their interaction on dense molecular clumps by observing the Large Magellanic Cloud (LMC) star-forming regions N48 and N49, which are located between two SGSs, LMC 4 and LMC 5. {sup 12}CO (J = 3-2, 1-0) and {sup 13}CO(J = 1-0) observations with the ASTE and Mopra telescopes have been carried out toward these regions. A clumpy distribution of dense molecular clumps is revealed with 7 pc spatial resolution. Large velocity gradient analysis shows that the molecular hydrogen densities (n(H{sub 2})) of the clumps are distributed from low to high density (10{sup 3}-10{sup 5} cm{sup 3}) and their kinetic temperatures (T {sub kin}) are typically high (greater than 50 K). These clumps seem to be in the early stages of star formation, as also indicated from the distribution of H?, young stellar object candidates, and IR emission. We found that the N48 region is located in the high column density H I envelope at the interface of the two SGSs and the star formation is relatively evolved, whereas the N49 region is associated with LMC 5 alone and the star formation is quiet. The clumps in the N48 region typically show high n(H{sub 2}) and T {sub kin}, which are as dense and warm as the clumps in LMC massive cluster-forming areas (30 Dor, N159). These results suggest that the large-scale structure of the SGSs, especially the interaction of two SGSs, works efficiently on the formation of dense molecular clumps and stars.

  19. THE PROPER MOTION OF THE MAGELLANIC CLOUDS. I. FIRST RESULTS AND DESCRIPTION OF THE PROGRAM

    SciTech Connect (OSTI)

    Costa, Edgardo; Mendez, Rene A.; Moyano, Maximiliano; Pedreros, Mario H.; Gallart, Carme; Noel, Noelia; Baume, Gustavo E-mail: rmendez@das.uchile.cl E-mail: mmoyano@mpia-hd.mpg.de E-mail: carme@iac.es E-mail: gbaume@gmail.com

    2009-05-15

    We present the first results of a ground-based program to determine the proper motion of the Magellanic Clouds (MCs) relative to background quasars (QSO), being carried out using the Irenee du Pont 2.5 m telescope at Las Campanas Observatory, Chile. Eleven QSO fields have been targeted in the Small Magellanic Cloud (SMC) over a time base of six years, and with seven epochs of observation. One quasar field was targeted in the Large Magellanic Cloud (LMC), over a time base of five years, and with six epochs of observation. The shorter time base in the case of the LMC is compensated by the much larger amount of high-quality astrometry frames that could be secured for the LMC quasar field (124 frames), compared to the SMC fields (an average of roughly 45 frames). In this paper, we present final results for field Q0557-6713 in the LMC and field Q0036-7227 in the SMC. From field Q0557-6713, we have obtained a measured proper motion of {mu}{sub {alpha}}cos {delta} = +1.95 {+-} 0.13 mas yr{sup -1}, {mu}{sub {delta}} = +0.43 {+-} 0.18 mas yr{sup -1} for the LMC. From field Q0036-7227, we have obtained a measured proper motion of {mu}{sub {alpha}} cos{delta} = +0.95 {+-} 0.29 mas yr{sup -1}, {mu}{sub {delta}} = -1.14 {+-} 0.18 mas yr{sup -1} for the SMC. Although we went through the full procedure for another SMC field (QJ0036-7225), on account of unsolvable astrometric difficulties caused by blending of the QSO image, it was impossible to derive a reliable proper motion. Current model rotation curves for the plane of the LMC indicate that the rotational velocity (V {sub rot}) at the position of LMC field Q0557-6713 can be as low as 50 km s{sup -1}, or as high as 120 km s{sup -1}. A correction for perspective and rotation effects leads to a center of mass proper motion for the LMC of {mu}{sub {alpha}} cos{delta} = +1.82 {+-} 0.13 mas yr{sup -1}, {mu}{sub {delta}} = +0.39 {+-} 0.15 mas yr{sup -1} (V {sub rot} = 50 km s{sup -1}), and to {mu}{sub {alpha}} cos{delta} = +1

  20. THE MID-INFRARED EXTINCTION LAW IN THE LARGE MAGELLANIC CLOUD

    SciTech Connect (OSTI)

    Gao, Jian; Jiang, B. W.; Xue, M. Y.; Li, Aigen E-mail: bjiang@bnu.edu.cn

    2013-10-10

    Based on photometric data from the Spitzer/SAGE survey, using red giants as extinction tracers, the mid-infrared (MIR) extinction laws in the Large Magellanic Cloud (LMC) are derived for the first time in the form of A{sub λ}/A{sub K{sub S}}. This quantity refers to the extinction in the four Infrared Array Camera (IRAC) bands (i.e., [3.6], [4.5], [5.8], and [8.0] μm) relative to the Two Micron All Sky Survey K{sub S} band at 2.16 μm. We obtain the near-infrared extinction coefficient to be E(J – H)/E(H – K{sub S} ) ≈ 1.29 ± 0.04 and E(J – K{sub S} )/E(H – K{sub S} ) ≈ 1.94 ± 0.04. The wavelength dependence of the MIR extinction A{sub λ}/A{sub K{sub S}} in the LMC varies from one sightline to another. The overall mean MIR extinction is A{sub [3.6]}/A{sub K{sub S}}∼0.72±0.03, A{sub [4.5]}/A{sub K{sub S}}∼0.94±0.03, A{sub [5.8]}/A{sub K{sub S}}∼0.58±0.04, and A{sub [8.0]}/A{sub K{sub S}}∼0.62±0.05. Except for the extinction in the IRAC [4.5] μm band, which may be contaminated by the 4.6 μm CO gas absorption of red giants used to trace LMC extinction, the extinction in the other three IRAC bands show a flat curve, close to the Milky Way R{sub V} = 5.5 model extinction curve, where R{sub V} is the optical total-to-selective extinction ratio. The possible systematic bias caused by the correlated uncertainties of K{sub S} – λ and J – K{sub S} is explored in terms of Monte Carlo simulations. We find that this bias could lead to an overestimation of A{sub λ}/A{sub K{sub S}} in the MIR.

  1. Examining the infrared variable star population discovered in the Small Magellanic Cloud using the SAGE-SMC survey

    SciTech Connect (OSTI)

    Polsdofer, Elizabeth; Marengo, M.; Seale, J.; Sewiło, M.; Vijh, U. P.; Terrazas, M.; Meixner, M.

    2015-02-01

    We present our study on the infrared variability of point sources in the Small Magellanic Cloud (SMC). We use the data from the Spitzer Space Telescope Legacy Program “Surveying the Agents of Galaxy Evolution in the Tidally Stripped, Low Metallicity Small Magellanic Cloud” (SAGE-SMC) and the “Spitzer Survey of the Small Magellanic Cloud” (S{sup 3}MC) survey, over three different epochs, separated by several months to 3 years. Variability in the thermal infrared is identified using a combination of Spitzer’s InfraRed Array Camera 3.6, 4.5, 5.8, and 8.0 μm bands, and the Multiband Imaging Photometer for Spitzer 24 μm band. An error-weighted flux difference between each pair of three epochs (“variability index”) is used to assess the variability of each source. A visual source inspection is used to validate the photometry and image quality. Out of ∼2 million sources in the SAGE-SMC catalog, 814 meet our variability criteria. We matched the list of variable star candidates to the catalogs of SMC sources classified with other methods, available in the literature. Carbon-rich Asymptotic Giant Branch (AGB) stars make up the majority (61%) of our variable sources, with about a third of all of our sources being classified as extreme AGB stars. We find a small, but significant population of oxygen-rich (O-rich) AGB (8.6%), Red Supergiant (2.8%), and Red Giant Branch (<1%) stars. Other matches to the literature include Cepheid variable stars (8.6%), early type stars (2.8%), Young-stellar objects (5.8%), and background galaxies (1.2%). We found a candidate OH maser star, SSTISAGE1C J005212.88-730852.8, which is a variable O-rich AGB star, and would be the first OH/IR star in the SMC, if confirmed. We measured the infrared variability of a rare RV Tau variable (a post-AGB star) that has recently left the AGB phase. 59 variable stars from our list remain unclassified.

  2. THE DISCOVERY OF A RARE WO-TYPE WOLF-RAYET STAR IN THE LARGE MAGELLANIC CLOUD

    SciTech Connect (OSTI)

    Neugent, Kathryn F.; Massey, Philip; Morrell, Nidia E-mail: phil.massey@lowell.edu

    2012-12-01

    While observing OB stars within the most crowded regions of the Large Magellanic Cloud, we happened upon a new Wolf-Rayet (WR) star in Lucke-Hodge 41, the rich OB association that contains S Doradus and numerous other massive stars. At first glance the spectrum resembled that of a WC4 star, but closer examination showed strong O VI {lambda}{lambda}3811, 34 lines, leading us to classify it as a WO4. This is only the second known WO in the LMC, and the first known WO4 (the other being a WO3). This rarity is to be expected due to these stars' short lifespans as they represent the most advanced evolutionary stage in a massive star's lifetime before exploding as supernovae. This discovery shows that while the majority of WRs within the LMC have been discovered, there may be a few WRs left to be found.

  3. AgraGate Carbon Credits Corporation | Open Energy Information

    Open Energy Info (EERE)

    AgraGate Carbon Credits Corporation Jump to: navigation, search Name: AgraGate Carbon Credits Corporation Place: Des Moines, Iowa Zip: 50266 Product: Offset aggregators that work...

  4. Roeder Farms | Open Energy Information

    Open Energy Info (EERE)

    Developer 5045 Wind Partners Energy Purchaser Alliant Energy Location Des Moines IA Coordinates 43.29729211, -93.28315258 Show Map Loading map... "minzoom":false,"mapp...

  5. Iowa Office of Energy Independence | Open Energy Information

    Open Energy Info (EERE)

    navigation, search Name: Iowa Office of Energy Independence Place: Des Moines, Iowa Zip: IA 50319 Product: In 2007, Governor Culver and the Iowa State Legislature created the...

  6. Superior Energy Performance: Certifying Increased Energy Productivity...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    ... Management Working Group (EMWG) Waterwastewater Des Moines, IA (2) Delta Diablo, CA Ithaca, NY Kent County, DE Victor Valley, CA Alexandria (VA) Renew ...

  7. Iowa Department of Economic Development | Open Energy Information

    Open Energy Info (EERE)

    Department of Economic Development Jump to: navigation, search Name: Iowa Department of Economic Development Place: Des Moines, Iowa Zip: 50309 Product: Iowa economic development...

  8. 2016 High School Science Bowl Participating Teams | The Ames...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    (Bettendorf) Prince of Peace (Clinton) Regina (Iowa City) Roland-Story Shenandoah St. Albert (Council Bluffs) Union (La Porte City) Valley (West Des Moines) West Central Valley...

  9. Diffuse X-ray emission from the superbubbles N70 and N185 in the Large Magellanic Cloud

    SciTech Connect (OSTI)

    Reyes-Iturbide, J.; Rodríguez-González, A.; Velázquez, P. F.; Rosado, M.; Sánchez-Cruces, M.; Ambrocio-Cruz, P.

    2014-11-01

    We present a study of the diffuse X-ray emission from superbubbles (SBs) N70 (DEM L301) and N185 (DEM L25) located in the Large Magellanic Cloud, based on data from the XMM-Newton Satellite. We obtained spectra and images of these objects in the soft X-ray energy band. These X-ray spectra were fitted by a thermal plasma model, with temperatures of 2.6×10{sup 6} K and 2.3×10{sup 6} K, for N70 and N185, respectively. For N70, images show that X-ray emission comes from the inner regions of the SB when we compare the distribution of the X-ray and the optical emission, while for N185, the X-ray emission is partially confined by the optical shell. We suggest that the observed X-ray emission is caused by shock-heated gas, inside of the optical shells. We also obtained X-ray luminosities which exceed the values predicted by the standard analytical model. This fact shows that, in addition to the winds of the interior stars, it is necessary to consider another ingredient in the description, such as a supernova explosion, as has been proposed in previous numerical models.

  10. A VLT/FLAMES STUDY OF THE PECULIAR INTERMEDIATE-AGE LARGE MAGELLANIC CLOUD STAR CLUSTER NGC 1846. I. KINEMATICS

    SciTech Connect (OSTI)

    Mackey, A. D.; Da Costa, G. S.; Yong, D.; Ferguson, A. M. N.

    2013-01-01

    In this paper we present high-resolution VLT/FLAMES observations of red giant stars in the massive intermediate-age Large Magellanic Cloud star cluster NGC 1846, which, on the basis of its extended main-sequence turnoff (EMSTO), possesses an internal age spread of Almost-Equal-To 300 Myr. We describe in detail our target selection and data reduction procedures, and construct a sample of 21 stars possessing radial velocities indicating their membership of NGC 1846 at high confidence. We consider high-resolution spectra of the planetary nebula Mo-17, and conclude that this object is also a member of the cluster. Our measured radial velocities allow us to conduct a detailed investigation of the internal kinematics of NGC 1846, the first time this has been done for an EMSTO system. The key result of this work is that the cluster exhibits a significant degree of systemic rotation, of a magnitude comparable to the mean velocity dispersion. Using an extensive suite of Monte Carlo models we demonstrate that, despite our relatively small sample size and the substantial fraction of unresolved binary stars in the cluster, the rotation signal we detect is very likely to be genuine. Our observations are in qualitative agreement with the predictions of simulations modeling the formation of multiple populations of stars in globular clusters, where a dynamically cold, rapidly rotating second generation is a common feature. NGC 1846 is less than one relaxation time old, so any dynamical signatures encoded during its formation ought to remain present.

  11. Des Plaines, Illinois: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    10th congressional district.12 Registered Energy Companies in Des Plaines, Illinois Gas Technology Institute (Partnership for Advanced Residential Retrofit) NARI National...

  12. Laboratoire de Physique des Interfaces et Couches Minces LPICM...

    Open Energy Info (EERE)

    Laboratoire de Physique des Interfaces et Couches Minces (LPICM) Place: Palaiseau, France Zip: 91128 Sector: Carbon Product: Research department of the Ecole Polytechnique in...

  13. Sécurité au-delà des mythes et des croyances

    SciTech Connect (OSTI)

    2010-06-24

    Présentation orale en français, support visuel en français et en anglais. La pire des failles de sécurité est l'impression de sécurité. Le décalage entre la compréhension que l’on a des technologies utilisées, et leurs potentiels réels, ainsi que l'impact potentiellement négatif qu'elles peuvent avoir sur nos vies, n'est pas toujours compris, ou pris en compte par la plupart d'entre-nous. On se contente de nos perceptions pour ne pas avoir à se confronter à la réalité... Alors qu'en est-il vraiment ? En matière de sécurité qui de l'humain ou des technologies a le contrôle ?

  14. Sécurité au-delà des mythes et des croyances

    ScienceCinema (OSTI)

    None

    2011-10-06

    Présentation orale en français, support visuel en français et en anglais. La pire des failles de sécurité est l'impression de sécurité. Le décalage entre la compréhension que l?on a des technologies utilisées, et leurs potentiels réels, ainsi que l'impact potentiellement négatif qu'elles peuvent avoir sur nos vies, n'est pas toujours compris, ou pris en compte par la plupart d'entre-nous. On se contente de nos perceptions pour ne pas avoir à se confronter à la réalité... Alors qu'en est-il vraiment ? En matière de sécurité qui de l'humain ou des technologies a le contrôle ?

  15. THE COS/UVES ABSORPTION SURVEY OF THE MAGELLANIC STREAM. II. EVIDENCE FOR A COMPLEX ENRICHMENT HISTORY OF THE STREAM FROM THE FAIRALL 9 SIGHTLINE

    SciTech Connect (OSTI)

    Richter, Philipp; Fechner, Cora [Institut fuer Physik und Astronomie, Universitaet Potsdam, Haus 28, Karl-Liebknecht-Str. 24/25, D-14476 Golm (Potsdam) (Germany); Fox, Andrew J. [Space Telescope Science Institute, Baltimore, MD 21218 (United States); Wakker, Bart P. [Department of Astronomy, University of Wisconsin-Madison, 475 North Charter Street, Madison, WI 53706 (United States); Lehner, Nicolas; Howk, J. Christopher [Department of Physics, University of Notre Dame, 225 Nieuwland Science Hall, Notre Dame, IN 46556 (United States); Bland-Hawthorn, Joss [Institute of Astronomy, School of Physics, University of Sydney, NSW 2006 (Australia); Ben Bekhti, Nadya [Argelander-Institut fuer Astronomie, Universitaet Bonn, Auf dem Huegel 71, D-53121 Bonn (Germany)

    2013-08-01

    We present a multi-wavelength study of the Magellanic Stream (MS), a massive gaseous structure in the Local Group that is believed to represent material stripped from the Magellanic Clouds. We use ultraviolet, optical and radio data obtained with HST/COS, VLT/UVES, FUSE, GASS, and ATCA to study metal abundances and physical conditions in the Stream toward the quasar Fairall 9. Line absorption in the MS from a large number of metal ions and from molecular hydrogen is detected in up to seven absorption components, indicating the presence of multi-phase gas. From the analysis of unsaturated S II absorption, in combination with a detailed photoionization model, we obtain a surprisingly high {alpha} abundance in the Stream toward Fairall 9 of [S/H] = -0.30 {+-} 0.04 (0.50 solar). This value is five times higher than what is found along other MS sightlines based on similar COS/UVES data sets. In contrast, the measured nitrogen abundance is found to be substantially lower ([N/H] = -1.15 {+-} 0.06), implying a very low [N/{alpha}] ratio of -0.85 dex. The substantial differences in the chemical composition of MS toward Fairall 9 compared to other sightlines point toward a complex enrichment history of the Stream. We favor a scenario, in which the gas toward Fairall 9 was locally enriched with {alpha} elements by massive stars and then was separated from the Magellanic Clouds before the delayed nitrogen enrichment from intermediate-mass stars could set in. Our results support (but do not require) the idea that there is a metal-enriched filament in the Stream toward Fairall 9 that originates in the LMC.

  16. THE COS/UVES ABSORPTION SURVEY OF THE MAGELLANIC STREAM. I. ONE-TENTH SOLAR ABUNDANCES ALONG THE BODY OF THE STREAM

    SciTech Connect (OSTI)

    Fox, Andrew J. [Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218 (United States); Richter, Philipp [Institut fuer Physik und Astronomie, Universitaet Potsdam, Haus 28, Karl-Liebknecht-Str. 24/25, D-14476 Potsdam (Germany); Wakker, Bart P. [Department of Astronomy, University of Wisconsin-Madison, 475 North Charter St., Madison, WI 53706 (United States); Lehner, Nicolas; Howk, J. Christopher [Department of Physics, University of Notre Dame, 225 Nieuwland Science Hall, Notre Dame, IN 46556 (United States); Ben Bekhti, Nadya [Argelander-Institut fuer Astronomie, Universitaet Bonn, Auf dem Huegel 71, D-53121 Bonn (Germany); Bland-Hawthorn, Joss [Institute of Astronomy, School of Physics, University of Sydney, NSW 2006 (Australia); Lucas, Stephen, E-mail: afox@stsci.edu [Department of Physics and Astronomy, University College London, Gower Street, London WC1E 6BT (United Kingdom)

    2013-08-01

    The Magellanic Stream (MS) is a massive and extended tail of multi-phase gas stripped out of the Magellanic Clouds and interacting with the Galactic halo. In this first paper of an ongoing program to study the Stream in absorption, we present a chemical abundance analysis based on HST/COS and VLT/UVES spectra of four active galactic nuclei (RBS 144, NGC 7714, PHL 2525, and HE 0056-3622) lying behind the MS. Two of these sightlines yield good MS metallicity measurements: toward RBS 144 we measure a low MS metallicity of [S/H] = [S II/H I] = -1.13 {+-} 0.16 while toward NGC 7714 we measure [O/H] = [O I/H I] = -1.24 {+-} 0.20. Taken together with the published MS metallicity toward NGC 7469, these measurements indicate a uniform abundance of Almost-Equal-To 0.1 solar along the main body of the Stream. This provides strong support to a scenario in which most of the Stream was tidally stripped from the SMC Almost-Equal-To 1.5-2.5 Gyr ago (a time at which the SMC had a metallicity of Almost-Equal-To 0.1 solar), as predicted by several N-body simulations. However, in Paper II of this series, we report a much higher metallicity (S/H = 0.5 solar) in the inner Stream toward Fairall 9, a direction sampling a filament of the MS that Nidever et al. claim can be traced kinematically to the Large Magellanic Cloud, not the Small Magellanic Cloud. This shows that the bifurcation of the Stream is evident in its metal enrichment, as well as its spatial extent and kinematics. Finally we measure a similar low metallicity [O/H] = [O I/H I] = -1.03 {+-} 0.18 in the v{sub LSR} = 150 km s{sup -1} cloud toward HE 0056-3622, which belongs to a population of anomalous velocity clouds near the south Galactic pole. This suggests these clouds are associated with the Stream or more distant structures (possibly the Sculptor Group, which lies in this direction at the same velocity), rather than tracing foreground Galactic material.

  17. From gas to stars in energetic environments: dense gas clumps in the 30 Doradus region within the Large Magellanic Cloud

    SciTech Connect (OSTI)

    Anderson, Crystal N.; Meier, David S.; Ott, Jrgen; Hughes, Annie; Wong, Tony; Looney, Leslie; Henkel, Christian; Chen, Rosie; Indebetouw, Remy; Muller, Erik; Pineda, Jorge L.; Seale, Jonathan

    2014-09-20

    We present parsec-scale interferometric maps of HCN(1-0) and HCO{sup +}(1-0) emission from dense gas in the star-forming region 30 Doradus, obtained using the Australia Telescope Compact Array. This extreme star-forming region, located in the Large Magellanic Cloud (LMC), is characterized by a very intense ultraviolet ionizing radiation field and sub-solar metallicity, both of which are expected to impact molecular cloud structure. We detect 13 bright, dense clumps within the 30 Doradus-10 giant molecular cloud. Some of the clumps are aligned along a filamentary structure with a characteristic spacing that is consistent with formation via varicose fluid instability. Our analysis shows that the filament is gravitationally unstable and collapsing to form stars. There is a good correlation between HCO{sup +} emission in the filament and signatures of recent star formation activity including H{sub 2}O masers and young stellar objects (YSOs). YSOs seem to continue along the same direction of the filament toward the massive compact star cluster R136 in the southwest. We present detailed comparisons of clump properties (masses, linewidths, and sizes) in 30Dor-10 to those in other star forming regions of the LMC (N159, N113, N105, and N44). Our analysis shows that the 30Dor-10 clumps have similar masses but wider linewidths and similar HCN/HCO{sup +} (1-0) line ratios as clumps detected in other LMC star-forming regions. Our results suggest that the dense molecular gas clumps in the interior of 30Dor-10 are well shielded against the intense ionizing field that is present in the 30 Doradus region.

  18. CX-003913: Categorical Exclusion Determination

    Broader source: Energy.gov [DOE]

    Iowa-City-Des MoinesCX(s) Applied: A1, A9, A11, B1.32, B5.1Date: 09/17/2010Location(s): Des Moines, IowaOffice(s): Energy Efficiency and Renewable Energy

  19. CX-006016: Categorical Exclusion Determination

    Broader source: Energy.gov [DOE]

    Energy Efficiency and Conservation Block Grant Program - Iowa-City-West Des MoinesCX(s) Applied: A1, A9, B2.5, B5.1Date: 05/27/2011Location(s): Des Moines, IowaOffice(s): Energy Efficiency and Renewable Energy

  20. Iowa Water and Wastewater Operators Seek SEP Certification in New Pilot Program

    Broader source: Energy.gov [DOE]

    The Des Moines Metropolitan Wastewater Reclamation Authority (WRA) and Des Moines Water Works have committed to participate in the Superior Energy Performance (SEP) program as the first members of a new program pilot. SEP recognizes facilities that meet the ISO 50001 global energy management standard and demonstrate improved energy performance.

  1. APUI Incubateur de l Ecole des Mines de Douai | Open Energy Informatio...

    Open Energy Info (EERE)

    APUI Incubateur de l Ecole des Mines de Douai Jump to: navigation, search Name: APUI Incubateur de l'Ecole des Mines de Douai Place: France Sector: Services Product: General...

  2. Spitzer SAGE-Spec: Near infrared spectroscopy, dust shells, and cool envelopes in extreme Large Magellanic Cloud asymptotic giant branch stars

    SciTech Connect (OSTI)

    Blum, R. D.; Srinivasan, S.; Kemper, F.; Ling, B.

    2014-11-01

    K-band spectra are presented for a sample of 39 Spitzer Infrared Spectrograph (IRS) SAGE-Spec sources in the Large Magellanic Cloud. The spectra exhibit characteristics in very good agreement with their positions in the near-infrared—Spitzer color-magnitude diagrams and their properties as deduced from the Spitzer IRS spectra. Specifically, the near-infrared spectra show strong atomic and molecular features representative of oxygen-rich and carbon-rich asymptotic giant branch stars, respectively. A small subset of stars was chosen from the luminous and red extreme ''tip'' of the color-magnitude diagram. These objects have properties consistent with dusty envelopes but also cool, carbon-rich ''stellar'' cores. Modest amounts of dust mass loss combine with the stellar spectral energy distribution to make these objects appear extreme in their near-infrared and mid-infrared colors. One object in our sample, HV 915, a known post-asymptotic giant branch star of the RV Tau type, exhibits CO 2.3 μm band head emission consistent with previous work that demonstrates that the object has a circumstellar disk.

  3. Search for gamma-ray emission from dark matter annihilation in the large magellanic cloud with the fermi large area telescope

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Buckley, Matthew R.; Charles, Eric; Gaskins, Jennifer M.; Brooks, Alyson M.; Drlica-Wagner, Alex; Martin, Pierrick; Zhao, Geng

    2015-05-05

    At a distance of 50 kpc and with a dark matter mass of ~1010 M⊙, the large magellanic cloud (LMC) is a natural target for indirect dark matter searches. We use five years of data from the Fermi Large Area Telescope (LAT) and updated models of the gamma-ray emission from standard astrophysical components to search for a dark matter annihilation signal from the LMC. We perform a rotation curve analysis to determine the dark matter distribution, setting a robust minimum on the amount of dark matter in the LMC, which we use to set conservative bounds on the annihilation cross section.more » The LMC emission is generally very well described by the standard astrophysical sources, with at most a 1–2σ excess identified near the kinematic center of the LMC once systematic uncertainties are taken into account. As a result, we place competitive bounds on the dark matter annihilation cross section as a function of dark matter particle mass and annihilation channel.« less

  4. Search for gamma-ray emission from dark matter annihilation in the large magellanic cloud with the fermi large area telescope

    SciTech Connect (OSTI)

    Buckley, Matthew R.; Charles, Eric; Gaskins, Jennifer M.; Brooks, Alyson M.; Drlica-Wagner, Alex; Martin, Pierrick; Zhao, Geng

    2015-05-05

    At a distance of 50 kpc and with a dark matter mass of ~1010 M, the large magellanic cloud (LMC) is a natural target for indirect dark matter searches. We use five years of data from the Fermi Large Area Telescope (LAT) and updated models of the gamma-ray emission from standard astrophysical components to search for a dark matter annihilation signal from the LMC. We perform a rotation curve analysis to determine the dark matter distribution, setting a robust minimum on the amount of dark matter in the LMC, which we use to set conservative bounds on the annihilation cross section. The LMC emission is generally very well described by the standard astrophysical sources, with at most a 1–2σ excess identified near the kinematic center of the LMC once systematic uncertainties are taken into account. As a result, we place competitive bounds on the dark matter annihilation cross section as a function of dark matter particle mass and annihilation channel.

  5. K{sub s} -BAND LUMINOSITY EVOLUTION OF THE ASYMPTOTIC GIANT BRANCH POPULATION BASED ON STAR CLUSTERS IN THE LARGE MAGELLANIC CLOUD

    SciTech Connect (OSTI)

    Ko, Youkyung; Lee, Myung Gyoon; Lim, Sungsoon E-mail: mglee@astro.snu.ac.kr

    2013-11-10

    We present a study of K{sub s} -band luminosity evolution of the asymptotic giant branch (AGB) population in simple stellar systems using star clusters in the Large Magellanic Cloud (LMC). We determine physical parameters of LMC star clusters including center coordinates, radii, and foreground reddenings. Ages of 83 star clusters are derived from isochrone fitting with the Padova models, and those of 19 star clusters are taken from the literature. The AGB stars in 102 star clusters with log(age) = 7.3-9.5 are selected using near-infrared color-magnitude diagrams based on Two Micron All Sky Survey photometry. Then we obtain the K{sub s} -band luminosity fraction of AGB stars in these star clusters as a function of ages. The K{sub s} -band luminosity fraction of AGB stars increases, on average, as age increases from log(age) ? 8.0, reaching a maximum at log(age) ? 8.5, and it decreases thereafter. There is a large scatter in the AGB luminosity fraction for given ages, which is mainly due to stochastic effects. We discuss this result in comparison with five simple stellar population models. The maximum K{sub s} -band AGB luminosity fraction for bright clusters is reproduced by the models that expect the value of 0.7-0.8 at log(age) = 8.5-8.7. We discuss the implication of our results with regard to the study of size and mass evolution of galaxies.

  6. Simulations of the OzDES AGN reverberation mapping project

    SciTech Connect (OSTI)

    King, Anthea L.; Martini, Paul; Davis, Tamara M.; Denney, K. D.; Kochanek, C. S.; Peterson, Bradley M.; Skielboe, Andreas; Vestergaard, Marianne; Huff, Eric; Watson, Darach; Banerji, Manda; McMahon, Richard; Sharp, Rob; Lidman, C.

    2015-08-26

    As part of the Australian spectroscopic dark energy survey (OzDES) we are carrying out a large-scale reverberation mapping study of ~500 quasars over five years in the 30 deg2 area of the Dark Energy Survey (DES) supernova fields. These quasars have redshifts ranging up to 4 and have apparent AB magnitudes between 16.8 mag < r < 22.5 mag. The aim of the survey is to measure time lags between fluctuations in the quasar continuum and broad emission-line fluxes of individual objects in order to measure black hole masses for a broad range of active galactic nuclei (AGN) and constrain the radius–luminosity (R–L) relationship. Here we investigate the expected efficiency of the OzDES reverberation mapping campaign and its possible extensions. We expect to recover lags for ~35–45 % of the quasars. AGN with shorter lags and greater variability are more likely to yield a lag measurement, and objects with lags ≲6 months or ~1 yr are expected to be recovered the most accurately. The baseline OzDES reverberation mapping campaign is predicted to produce an unbiased measurement of the R–L relationship parameters for Hβ, MgIIλ2798, and C IVλ1549. As a result, extending the baseline survey by either increasing the spectroscopic cadence, extending the survey season, or improving the emission-line flux measurement accuracy will significantly improve the R–L parameter constraints for all broad emission lines.

  7. Mutual Insurance Company of West

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Step : On the right side of the homepage under "Identity The Protection," click on "Create Member Account." Once you log in, create an additional username and password to For more information call - - or visit ARAGLegalCenter.com. Limitations and exclusions apply. Insurance products are underwritten by ARAG Insurance Company of Des Moines, Iowa, GuideOne ® Mutual Insurance Company of West Des Moines, Iowa or GuideOne Specialty Mutual Insurance Company of West Des Moines,

  8. Surveying the agents of galaxy evolution in the tidally stripped, low metallicity small Magellanic Cloud (SAGE-SMC). III. Young stellar objects

    SciTech Connect (OSTI)

    Sewiło, M.; Carlson, L. R.; Seale, J. P.; Meixner, M.; Gordon, K.; Shiao, B. E-mail: carlson@strw.leidenuniv.nl E-mail: meixner@stsci.edu E-mail: shiao@stsci.edu; and others

    2013-11-20

    The Spitzer Space Telescope Legacy Program SAGE-SMC allows global studies of resolved stellar populations in the SMC in a different environment than our Galaxy. Using the SAGE-SMC IRAC (3.6-8.0 μm) and MIPS (24 and 70 μm) catalogs and images combined with near-infrared (JHK {sub s}) and optical (UBVI) data, we identified a population of ∼1000 intermediate- to high-mass young stellar objects (YSOs) in the SMC (three times more than previously known). Our method of identifying YSO candidates builds on the method developed for the Large Magellanic Cloud by Whitney et al. with improvements based on what we learned from our subsequent studies and techniques described in the literature. We perform (1) color-magnitude cuts based on five color-magnitude diagrams (CMDs), (2) visual inspection of multi-wavelength images, and (3) spectral energy distribution (SED) fitting with YSO models. For each YSO candidate, we use its photometry to calculate a measure of our confidence that the source is not a non-YSO contaminant, but rather a true YSO, based on the source's location in the color-magnitude space with respect to non-YSOs. We use this CMD score and the SED fitting results to define two classes of sources: high-reliability YSO candidates and possible YSO candidates. We found that, due to polycyclic aromatic hydrocarbon emission, about half of our sources have [3.6]-[4.5] and [4.5]-[5.8] colors not predicted by previous YSO models. The YSO candidates are spatially correlated with gas tracers.

  9. A MAGELLAN MIKE AND SPITZER MIPS STUDY OF 1.5-1.0 M{sub sun} STARS IN SCORPIUS-CENTAURUS

    SciTech Connect (OSTI)

    Chen, Christine H.; Bitner, Martin A.; Mamajek, Eric E.; Pecaut, Mark; Su, Kate Y. L.; Weinberger, Alycia J.

    2011-09-10

    We obtained Spitzer Space Telescope Multiband Imaging Photometer for Spitzer (MIPS) 24 {mu}m and 70 {mu}m observations of 182 nearby, Hipparcos F- and G-type common proper motion single and binary systems in the nearest OB association, Scorpius-Centaurus. We also obtained Magellan/MIKE R {approx} 50,000 visual spectra at 3500-10500 A for 181 candidate ScoCen stars in single and binary systems. Combining our MIPS observations with those of other ScoCen stars in the literature, we estimate 24 {mu}m F+G-type disk fractions of 9/27 (33% {+-} 11%), 21/67 (31% {+-} 7%), and 25/71 (35% {+-} 7%) for Upper Scorpius ({approx}10 Myr), Upper Centaurus Lupus ({approx}15 Myr), and Lower Centaurus Crux ({approx}17 Myr), respectively. We confirm previous IRAS and MIPS excess detections and present new discoveries of 41 protoplanetary and debris disk systems, with fractional infrared luminosities ranging from L{sub IR}/L{sub *} = 10{sup -5} to 10{sup -2} and grain temperatures ranging from T{sub gr} = 40-300 K. We searched for an increase in 24 {mu}m excess at an age of 15-20 Myr, consistent with the onset of debris production predicted by coagulation N-body simulations of outer planetary systems. We found such an increase around 1.5 M{sub sun} stars but discovered a decrease in the 24 {mu}m excess around 1.0 M{sub sun} stars. We additionally discovered that the 24 {mu}m excess around 1.0 M{sub sun} stars is larger than predicted by self-stirred models. Finally, we found a weak anti-correlation between fractional infrared luminosity (L{sub IR}/L{sub *}) and chromospheric activity (R'{sub HK}), that may be the result of differences in stellar properties, such as mass, luminosity, and/or winds.

  10. ULTRA-DEEP HUBBLE SPACE TELESCOPE IMAGING OF THE SMALL MAGELLANIC CLOUD: THE INITIAL MASS FUNCTION OF STARS WITH M {approx}< 1 M {sub Sun}

    SciTech Connect (OSTI)

    Kalirai, Jason S.; Anderson, Jay; Dotter, Aaron; Reid, I. Neill; Richer, Harvey B.; Fahlman, Gregory G.; Hansen, Brad M. S.; Rich, R. Michael; Hurley, Jarrod; Shara, Michael M. E-mail: jayander@stsci.edu E-mail: richer@astro.ubc.ca E-mail: hansen@astro.ucla.edu E-mail: jhurley@swin.edu.au

    2013-02-15

    We present a new measurement of the stellar initial mass function (IMF) based on ultra-deep, high-resolution photometry of >5000 stars in the outskirts of the Small Magellanic Cloud (SMC) galaxy. The Hubble Space Telescope (HST) Advanced Camera for Surveys observations reveal this rich, cospatial population behind the foreground globular cluster 47 Tuc, which we targeted for 121 HST orbits. The stellar main sequence of the SMC is measured in the F606W, F814W color-magnitude diagram down to {approx}30th magnitude, and is cleanly separated from the foreground star cluster population using proper motions. We simulate the SMC population by extracting stellar masses (single and unresolved binaries) from specific IMFs and converting those masses to luminosities in our bandpasses. The corresponding photometry for these simulated stars is drawn directly from a rich cloud of 4 million artificial stars, thereby accounting for the real photometric scatter and completeness of the data. Over a continuous and well-populated mass range of M = 0.37-0.93 M {sub Sun} (e.g., down to a {approx}75% completeness limit at F606W = 28.7), we demonstrate that the IMF is well represented by a single power-law form with slope {alpha} = -1.90 ({sup +0.15} {sub -0.10}) (3{sigma} error) (e.g., dN/dM{proportional_to} M {sup {alpha}}). This is shallower than the Salpeter slope of {alpha} = -2.35, which agrees with the observed stellar luminosity function at higher masses. Our results indicate that the IMF does not turn over to a more shallow power-law form within this mass range. We discuss implications of this result for the theory of star formation, the inferred masses of galaxies, and the (lack of a) variation of the IMF with metallicity.

  11. METAL-POOR STARS OBSERVED WITH THE MAGELLAN TELESCOPE. I. CONSTRAINTS ON PROGENITOR MASS AND METALLICITY OF AGB STARS UNDERGOING s-PROCESS NUCLEOSYNTHESIS

    SciTech Connect (OSTI)

    Placco, Vinicius M.; Rossi, Silvia; Frebel, Anna; Beers, Timothy C.; Karakas, Amanda I.; Kennedy, Catherine R.; Christlieb, Norbert; Stancliffe, Richard J.

    2013-06-20

    We present a comprehensive abundance analysis of two newly discovered carbon-enhanced metal-poor (CEMP) stars. HE 2138-3336 is a s-process-rich star with [Fe/H] = -2.79, and has the highest [Pb/Fe] abundance ratio measured thus far, if non-local thermodynamic equilibrium corrections are included ([Pb/Fe] = +3.84). HE 2258-6358, with [Fe/H] = -2.67, exhibits enrichments in both s- and r-process elements. These stars were selected from a sample of candidate metal-poor stars from the Hamburg/ESO objective-prism survey, and followed up with medium-resolution (R {approx} 2000) spectroscopy with GEMINI/GMOS. We report here on derived abundances (or limits) for a total of 34 elements in each star, based on high-resolution (R {approx} 30, 000) spectroscopy obtained with Magellan-Clay/MIKE. Our results are compared to predictions from new theoretical asymptotic giant branch (AGB) nucleosynthesis models of 1.3 M{sub Sun} with [Fe/H] = -2.5 and -2.8, as well as to a set of AGB models of 1.0 to 6.0 M{sub Sun} at [Fe/H] = -2.3. The agreement with the model predictions suggests that the neutron-capture material in HE 2138-3336 originated from mass transfer from a binary companion star that previously went through the AGB phase, whereas for HE 2258-6358, an additional process has to be taken into account to explain its abundance pattern. We find that a narrow range of progenitor masses (1.0 {<=} M(M{sub Sun }) {<=} 1.3) and metallicities (-2.8 {<=} [Fe/H] {<=}-2.5) yield the best agreement with our observed elemental abundance patterns.

  12. DUST AND GAS IN THE MAGELLANIC CLOUDS FROM THE HERITAGE HERSCHEL KEY PROJECT. I. DUST PROPERTIES AND INSIGHTS INTO THE ORIGIN OF THE SUBMILLIMETER EXCESS EMISSION

    SciTech Connect (OSTI)

    Gordon, Karl D.; Roman-Duval, Julia; Meixner, Margaret; Bot, Caroline; Babler, Brian; Bernard, Jean-Philippe; Bolatto, Alberto; Jameson, Katherine; Boyer, Martha L.; Clayton, Geoffrey C.; Engelbracht, Charles; Fukui, Yasuo; Galametz, Maud; Galliano, Frederic; Hony, Sacha; Lebouteiller, Vianney; Indebetouw, Remy; Israel, Frank P.; Kawamura, Akiko; and others

    2014-12-20

    The dust properties in the Large and Small Magellanic clouds (LMC/SMC) are studied using the HERITAGE Herschel Key Project photometric data in five bands from 100 to 500?m. Three simple models of dust emission were fit to the observations: a single temperature blackbody modified by a power-law emissivity (SMBB), a single temperature blackbody modified by a broken power-law emissivity (BEMBB), and two blackbodies with different temperatures, both modified by the same power-law emissivity (TTMBB). Using these models, we investigate the origin of the submillimeter excess, defined as the submillimeter emission above that expected from SMBB models fit to observations <200 ?m. We find that the BEMBB model produces the lowest fit residuals with pixel-averaged 500?m submillimeter excesses of 27% and 43% for the LMC and SMC, respectively. Adopting gas masses from previous works, the gas-to-dust ratios calculated from our fitting results show that the TTMBB fits require significantly more dust than are available even if all the metals present in the interstellar medium (ISM) were condensed into dust. This indicates that the submillimeter excess is more likely to be due to emissivity variations than a second population of colder dust. We derive integrated dust masses of (7.3 1.7) 10{sup 5} and (8.3 2.1) 10{sup 4} M {sub ?} for the LMC and SMC, respectively. We find significant correlations between the submillimeter excess and other dust properties; further work is needed to determine the relative contributions of fitting noise and ISM physics to the correlations.

  13. THE INFLUENCE OF SUPERNOVA REMNANTS ON THE INTERSTELLAR MEDIUM IN THE LARGE MAGELLANIC CLOUD SEEN AT 20-600 μm WAVELENGTHS

    SciTech Connect (OSTI)

    Lakićević, Maša; Van Loon, Jacco Th.; Meixner, Margaret; Gordon, Karl; Roman-Duval, Julia; Seale, Jonathan; Bot, Caroline; Babler, Brian; Bolatto, Alberto; Engelbracht, Chad; Misselt, Karl; Montiel, Edward; Filipović, Miroslav; Hony, Sacha; Okumura, K.; Panuzzo, Pasquale; Sauvage, Marc; Patat, Ferdinando; Sonneborn, George; and others

    2015-01-20

    We present the analysis of supernova remnants (SNRs) in the Large Magellanic Cloud (LMC) and their influence on the environment at far-infrared (FIR) and submillimeter wavelengths. We use new observations obtained with the Herschel Space Observatory and archival data obtained with the Spitzer Space Telescope, to make the first FIR atlas of these objects. The SNRs are not clearly discernible at FIR wavelengths; however, their influence becomes apparent in maps of dust mass and dust temperature, which we constructed by fitting a modified blackbody to the observed spectral energy distribution in each sightline. Most of the dust that is seen is pre-existing interstellar dust in which SNRs leave imprints. The temperature maps clearly reveal SNRs heating surrounding dust, while the mass maps indicate the removal of 3.7{sub −2.5}{sup +7.5} M {sub ☉} of dust per SNR. This agrees with the calculations by others that significant amounts of dust are sputtered by SNRs. Under the assumption that dust is sputtered and not merely pushed away, we estimate a dust destruction rate in the LMC of 0.037{sub −0.025}{sup +0.075} M {sub ☉} yr{sup –1} due to SNRs, yielding an average lifetime for interstellar dust of 2{sub −1.3}{sup +4.0}×10{sup 7} yr. We conclude that sputtering of dust by SNRs may be an important ingredient in models of galactic evolution, that supernovae may destroy more dust than they produce, and that they therefore may not be net producers of long lived dust in galaxies.

  14. Identification of a jet-driven supernova remnant in the Small Magellanic Cloud: Possible evidence for the enhancement of bipolar explosions at low metallicity

    SciTech Connect (OSTI)

    Lopez, Laura A.; Castro, Daniel; Slane, Patrick O.; Ramirez-Ruiz, Enrico; Badenes, Carles

    2014-06-10

    Recent evidence has suggested that the supernova remnant (SNR) 010472.3 in the Small Magellanic Cloud (SMC) may be the result of a 'prompt' Type Ia SN on the basis of enhanced iron abundances and its association with a star-forming region. In this paper, we present evidence that SNR 010472.3 arose from a jet-driven bipolar core-collapse (CC) SN. Specifically, we use serendipitous Chandra data of SNR 010472.3 taken because of its proximity to the calibration source SNR E010272.3. We analyze 56 Advanced CCD Imaging Spectrometer (ACIS) observations of SNR 010472.3 to produce imaging and spectra with an effective exposure of 528.6 ks. We demonstrate that SNR 010472.3 is highly elliptical relative to other nearby young SNRs, suggesting a CC SN origin. Furthermore, we compare ejecta abundances derived from spectral fits to nucleosynthetic yields of Type Ia and CC SNe, and we find that the iron, neon, and silicon abundances are consistent with either a spherical CC SN of a 18-20 M {sub ?} progenitor or an aspherical CC SN of a 25 M {sub ?} progenitor. We show that the star formation history at the site of SNR 010472.3 is also consistent with a CC origin. Given the bipolar morphology of the SNR, we favor the aspherical CC SN scenario. This result may suggest jet-driven SNe occur frequently in the low-metallicity environment of the SMC, consistent with the observational and theoretical work on broad-line Type Ic SNe and long-duration gamma-ray bursts.

  15. New clues to the cause of extended main-sequence turnoffs in intermediate-age star clusters in the Magellanic Clouds

    SciTech Connect (OSTI)

    Correnti, Matteo; Goudfrooij, Paul; Kalirai, Jason S.; Girardi, Leo; Puzia, Thomas H.; Kerber, Leandro E-mail: goudfroo@stsci.edu E-mail: leo.girardi@oapd.inaf.it E-mail: lkerber@gmail.com

    2014-10-01

    We use the Wide Field Camera 3 on board the Hubble Space Telescope (HST) to obtain deep, high-resolution images of two intermediate-age star clusters in the Large Magellanic Cloud of relatively low mass (?10{sup 4} M {sub ?}) and significantly different core radii, namely NGC 2209 and NGC 2249. For comparison purposes, we also reanalyzed archival HST images of NGC 1795 and IC 2146, two other relatively low-mass star clusters. From the comparison of the observed color-magnitude diagrams with Monte Carlo simulations, we find that the main-sequence turnoff (MSTO) regions in NGC 2209 and NGC 2249 are significantly wider than that derived from simulations of simple stellar populations, while those in NGC 1795 and IC 2146 are not. We determine the evolution of the clusters' masses and escape velocities from an age of 10 Myr to the present age. We find that differences among these clusters can be explained by dynamical evolution arguments if the currently extended clusters (NGC 2209 and IC 2146) experienced stronger levels of initial mass segregation than the currently compact ones (NGC 2249 and NGC 1795). Under this assumption, we find that NGC 2209 and NGC 2249 have estimated escape velocities, V {sub esc} ? 15 km s{sup 1} at an age of 10 Myr, large enough to retain material ejected by slow winds of first-generation stars, while the two clusters that do not feature extended MSTOs have V {sub esc} ? 12 km s{sup 1} at that age. These results suggest that the extended MSTO phenomenon can be better explained by a range of stellar ages rather than a range of stellar rotation velocities or interacting binaries.

  16. The DES Science Verification Weak Lensing Shear Catalogs

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Jarvis, M.

    2016-05-01

    We present weak lensing shear catalogs for 139 square degrees of data taken during the Science Verification (SV) time for the new Dark Energy Camera (DECam) being used for the Dark Energy Survey (DES). We describe our object selection, point spread function estimation and shear measurement procedures using two independent shear pipelines, IM3SHAPE and NGMIX, which produce catalogs of 2.12 million and 3.44 million galaxies respectively. We also detail a set of null tests for the shear measurements and find that they pass the requirements for systematic errors at the level necessary for weak lensing science applications using the SVmore » data. Furthermore, we discuss some of the planned algorithmic improvements that will be necessary to produce sufficiently accurate shear catalogs for the full 5-year DES, which is expected to cover 5000 square degrees.« less

  17. The DES Science Verification Weak Lensing Shear Catalogs

    SciTech Connect (OSTI)

    Jarvis, M.

    2015-07-20

    We present weak lensing shear catalogs for 139 square degrees of data taken during the Science Verification (SV) time for the new Dark Energy Camera (DECam) being used for the Dark Energy Survey (DES). We describe our object selection, point spread function estimation and shear measurement procedures using two independent shear pipelines, IM3SHAPE and NGMIX, which produce catalogs of 2.12 million and 3.44 million galaxies respectively. We also detail a set of null tests for the shear measurements and find that they pass the requirements for systematic errors at the level necessary for weak lensing science applications using the SV data. Furthermore, we discuss some of the planned algorithmic improvements that will be necessary to produce sufficiently accurate shear catalogs for the full 5-year DES, which is expected to cover 5000 square degrees.

  18. Partager : des technologies de pointe au service de la société

    ScienceCinema (OSTI)

    None

    2011-10-06

    Médecine, climatologie, métrologie et informatique, les techniques utilisées par le LHC trouvent déjà des répercussions dans d?autres domaines scientifiques. Utilisant des techniques inédites, la physique des particules en fait bénéficier la société toute entière.

  19. Simulations of the OzDES AGN reverberation mapping project

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    King, Anthea L.; Martini, Paul; Davis, Tamara M.; Denney, K. D.; Kochanek, C. S.; Peterson, Bradley M.; Skielboe, Andreas; Vestergaard, Marianne; Huff, Eric; Watson, Darach; et al

    2015-08-26

    As part of the Australian spectroscopic dark energy survey (OzDES) we are carrying out a large-scale reverberation mapping study of ~500 quasars over five years in the 30 deg2 area of the Dark Energy Survey (DES) supernova fields. These quasars have redshifts ranging up to 4 and have apparent AB magnitudes between 16.8 mag < r < 22.5 mag. The aim of the survey is to measure time lags between fluctuations in the quasar continuum and broad emission-line fluxes of individual objects in order to measure black hole masses for a broad range of active galactic nuclei (AGN) and constrainmore » the radius–luminosity (R–L) relationship. Here we investigate the expected efficiency of the OzDES reverberation mapping campaign and its possible extensions. We expect to recover lags for ~35–45 % of the quasars. AGN with shorter lags and greater variability are more likely to yield a lag measurement, and objects with lags ≲6 months or ~1 yr are expected to be recovered the most accurately. The baseline OzDES reverberation mapping campaign is predicted to produce an unbiased measurement of the R–L relationship parameters for Hβ, MgIIλ2798, and C IVλ1549. As a result, extending the baseline survey by either increasing the spectroscopic cadence, extending the survey season, or improving the emission-line flux measurement accuracy will significantly improve the R–L parameter constraints for all broad emission lines.« less

  20. CMB lensing tomography with the DES Science Verification galaxies

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Giannantonio, T.

    2016-01-07

    We measure the cross-correlation between the galaxy density in the Dark Energy Survey (DES) Science Verification data and the lensing of the cosmic microwave background (CMB) as reconstructed with the Planck satellite and the South Pole Telescope (SPT). When using the DES main galaxy sample over the full redshift range 0.2 < zphot < 1.2, a cross-correlation signal is detected at 6σ and 4σ with SPT and Planck respectively. We then divide the DES galaxies into five photometric redshift bins, finding significant (>2σ) detections in all bins. Comparing to the fiducial Planck cosmology, we find the redshift evolution of themore » signal matches expectations, although the amplitude is consistently lower than predicted across redshift bins. We test for possible systematics that could affect our result and find no evidence for significant contamination. Finally, we demonstrate how these measurements can be used to constrain the growth of structure across cosmic time. We find the data are fit by a model in which the amplitude of structure in the z < 1.2 universe is 0.73 ± 0.16 times as large as predicted in the LCDM Planck cosmology, a 1.7σ deviation.« less

  1. Cosmology from Cosmic Shear with DES Science Verification Data

    SciTech Connect (OSTI)

    Abbott, T.

    2015-07-20

    We present the first constraints on cosmology from the Dark Energy Survey (DES), using weak lensing measurements from the preliminary Science Verification (SV) data. We use 139 square degrees of SV data, which is less than 3% of the full DES survey area. Using cosmic shear 2-point measurements over three redshift bins we find ?8(m=0.3)0.5 = 0:81 0:06 (68% confidence), after marginalising over 7 systematics parameters and 3 other cosmological parameters. Furthermore, we examine the robustness of our results to the choice of data vector and systematics assumed, and find them to be stable. About 20% of our error bar comes from marginalising over shear and photometric redshift calibration uncertainties. The current state-of-the-art cosmic shear measurements from CFHTLenS are mildly discrepant with the cosmological constraints from Planck CMB data. Our results are consistent with both datasets. Our uncertainties are ~30% larger than those from CFHTLenS when we carry out a comparable analysis of the two datasets, which we attribute largely to the lower number density of our shear catalogue. We investigate constraints on dark energy and find that, with this small fraction of the full survey, the DES SV constraints make negligible impact on the Planck constraints. The moderate disagreement between the CFHTLenS and Planck values of ?8(?m=0.3)0.5 is present regardless of the value of w.

  2. Mutual Insurance Company of West

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    call 800-247-4184 or visit ARAGLegalCenter.com. Limitations and exclusions apply. Insurance products are underwritten by ARAG Insurance Company of Des Moines, Iowa, GuideOne ...

  3. West Burlington, Iowa: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    Hide Map This article is a stub. You can help OpenEI by expanding it. West Burlington is a city in Des Moines County, Iowa. It falls under Iowa's 2nd...

  4. Category:SmallHotel | Open Energy Information

    Open Energy Info (EERE)

    Cleveland OH Ohio Power Co.png SVSmallHotel Cleveland... 68 KB SVSmallHotel Concord NH Public Service Co of NH.png SVSmallHotel Concord N... 71 KB SVSmallHotel Des Moines IA...

  5. CX-004285: Categorical Exclusion Determination

    Broader source: Energy.gov [DOE]

    Indigo Dawn Green and Main Street ProjectCX(s) Applied: A9, B5.1Date: 10/20/2010Location(s): Des Moines, IowaOffice(s): Energy Efficiency and Renewable Energy, Golden Field Office

  6. A DES ASIC Suitable for Network Encryption at 10 Gbps and Beyond

    SciTech Connect (OSTI)

    Gass, Karl; Pierson, Lyndon G.; Robertson, Perry J.; Wilcox, D. Craig; Witzke, Edward L.

    1999-04-30

    The Sandia National Laboratories (SNL) Data Encryption Standard (DES) Application Specific Integrated Circuit (ASIC) is the fastest known implementation of the DES algorithm as defined in the Federal Information Processing Standards (FIPS) Publication 46-2. DES is used for protecting data by cryptographic means. The SNL DES ASIC, over 10 times faster than other currently available DES chips, is a high-speed, filly pipelined implementation offering encryption, decryption, unique key input, or algorithm bypassing on each clock cycle. Operating beyond 105 MHz on 64 bit words, this device is capable of data throughputs greater than 6.7 Billion bits per second (tester limited). Simulations predict proper operation up to 9.28 Billion bits per second. In low frequency, low data rate applications, the ASIC consumes less that one milliwatt of power. The device has features for passing control signals synchronized to throughput data. Three SNL DES ASICS may be easily cascaded to provide the much greater security of triple-key, triple-DES.

  7. DUST AND GAS IN THE MAGELLANIC CLOUDS FROM THE HERITAGE HERSCHEL KEY PROJECT. II. GAS-TO-DUST RATIO VARIATIONS ACROSS INTERSTELLAR MEDIUM PHASES

    SciTech Connect (OSTI)

    Roman-Duval, Julia; Gordon, Karl D.; Meixner, Margaret; Bot, Caroline; Bolatto, Alberto; Jameson, Katherine; Hughes, Annie; Hony, Sacha; Wong, Tony; Babler, Brian; Bernard, Jean-Philippe; Clayton, Geoffrey C.; Fukui, Yasuo; Galametz, Maud; Galliano, Frederic; Lebouteiller, Vianney; Lee, Min-Young; Israel, Frank; Li, Aigen; and others

    2014-12-20

    The spatial variations of the gas-to-dust ratio (GDR) provide constraints on the chemical evolution and lifecycle of dust in galaxies. We examine the relation between dust and gas at 10-50pc resolution in the Large and Small Magellanic Clouds (LMC and SMC) based on Herschel far-infrared (FIR), H I 21cm, CO, and H? observations. In the diffuse atomic interstellar medium (ISM), we derive the GDR as the slope of the dust-gas relation and find GDRs of 380{sub ?130}{sup +250} 3 in the LMC, and 1200{sub ?420}{sup +1600} 120 in the SMC, not including helium. The atomic-to-molecular transition is located at dust surface densities of 0.05 M {sub ?}pc{sup 2} in the LMC and 0.03 M {sub ?}pc{sup 2} in the SMC, corresponding to A {sub V} ? 0.4 and 0.2, respectively. We investigate the range of CO-to-H{sub 2} conversion factor to best account for all the molecular gas in the beam of the observations, and find upper limits on X {sub CO} to be 6 10{sup 20}cm{sup 2}K{sup 1}km{sup 1} s in the LMC (Z= 0.5 Z {sub ?}) at 15pc resolution, and 4 10{sup 21}cm{sup 2}K{sup 1}km{sup 1} s in the SMC (Z= 0.2 Z {sub ?}) at 45pc resolution. In the LMC, the slope of the dust-gas relation in the dense ISM is lower than in the diffuse ISM by a factor ?2, even after accounting for the effects of CO-dark H{sub 2} in the translucent envelopes of molecular clouds. Coagulation of dust grains and the subsequent dust emissivity increase in molecular clouds, and/or accretion of gas-phase metals onto dust grains, and the subsequent dust abundance (dust-to-gas ratio) increase in molecular clouds could explain the observations. In the SMC, variations in the dust-gas slope caused by coagulation or accretion are degenerate with the effects of CO-dark H{sub 2}. Within the expected 5-20times Galactic X {sub CO} range, the dust-gas slope can be either constant or decrease by a factor of several across ISM phases. Further modeling and observations are required to break the degeneracy

  8. Magellan Queues End November 30

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    and Status Mon, Nov 28 westmere queue drain - 08:00 - DONE remove - 10:20 - DONE serial queue add westmere nodes - 10:40 - DONE Tue, Nov 29 magxlmem queue drain - 08:00 -...

  9. Explorer : des clés pour mieux comprendre la matière

    ScienceCinema (OSTI)

    None

    2011-10-06

    Le LHC va-t-il bouleverser les théories de l'infiniment petit ? Les physiciens aimeraient que l'accélérateur fasse trembler le modèle standard. Cette théorie des particules élémentaires et des forces laisse de nombreuses zones d'ombre. Le LHC et ses expériences ont été conçus pour les éclairer.

  10. Cosmic Shear Measurements with DES Science Verification Data

    SciTech Connect (OSTI)

    Becker, M. R.

    2015-07-20

    We present measurements of weak gravitational lensing cosmic shear two-point statistics using Dark Energy Survey Science Verification data. We demonstrate that our results are robust to the choice of shear measurement pipeline, either ngmix or im3shape, and robust to the choice of two-point statistic, including both real and Fourier-space statistics. Our results pass a suite of null tests including tests for B-mode contamination and direct tests for any dependence of the two-point functions on a set of 16 observing conditions and galaxy properties, such as seeing, airmass, galaxy color, galaxy magnitude, etc. We use a large suite of simulations to compute the covariance matrix of the cosmic shear measurements and assign statistical significance to our null tests. We find that our covariance matrix is consistent with the halo model prediction, indicating that it has the appropriate level of halo sample variance. We also compare the same jackknife procedure applied to the data and the simulations in order to search for additional sources of noise not captured by the simulations. We find no statistically significant extra sources of noise in the data. The overall detection significance with tomography for our highest source density catalog is 9.7σ. Cosmological constraints from the measurements in this work are presented in a companion paper (DES et al. 2015).

  11. POPULATION PARAMETERS OF INTERMEDIATE-AGE STAR CLUSTERS IN THE LARGE MAGELLANIC CLOUD. III. DYNAMICAL EVIDENCE FOR A RANGE OF AGES BEING RESPONSIBLE FOR EXTENDED MAIN-SEQUENCE TURNOFFS

    SciTech Connect (OSTI)

    Goudfrooij, Paul; Kozhurina-Platais, Vera; Puzia, Thomas H.; Chandar, Rupali E-mail: verap@stsci.edu E-mail: rupali.chandar@utoledo.edu

    2011-08-10

    We present a new analysis of 11 intermediate-age (1-2 Gyr) star clusters in the Large Magellanic Cloud based on Hubble Space Telescope imaging data. Seven of the clusters feature main-sequence turnoff (MSTO) regions that are wider than can be accounted for by a simple stellar population, whereas their red giant branches (RGBs) indicate a single value of [Fe/H]. The star clusters cover a range in present-day mass from about 1 x 10{sup 4} M{sub sun} to 2 x 10{sup 5} M{sub sun}. We compare radial distributions of stars in the upper and lower parts of the MSTO region, and calculate cluster masses and escape velocities from the present time back to a cluster age of 10 Myr. Our main result is that for all clusters in our sample with estimated escape velocities v{sub esc} {approx}> 15 km s{sup -1} at an age of 10 Myr, the stars in the brightest half of the MSTO region are significantly more centrally concentrated than the stars in the faintest half and more massive RGB and asymptotic giant branch stars. This is not the case for clusters with v{sub esc} {approx}< 10 km s{sup -1} at an age of 10 Myr. We argue that the wide MSTO region of such clusters is caused mainly by a {approx}200-500 Myr range in the ages of cluster stars due to extended star formation within the cluster from material shed by first-generation stars featuring slow stellar winds. Dilution of this enriched material by accretion of ambient interstellar matter is deemed plausible if the spread of [Fe/H] in this ambient gas was very small when the second-generation stars were formed in the cluster.

  12. DES13S2cmm: The first superluminous supernova from the Dark Energy Survey

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Papadopoulos, A.; Plazas, A. A.; D"Andrea, C. B.; Sullivan, M.; Nichol, R. C.; Barbary, K.; Biswas, R.; Brown, P. J.; Covarrubias, R. A.; Finley, D. A.; et al

    2015-03-23

    We present DES13S2cmm, the first spectroscopically-confirmed superluminous supernova (SLSN) from the Dark Energy Survey (DES). We briefly discuss the data and search algorithm used to find this event in the first year of DES operations, and outline the spectroscopic data obtained from the European Southern Observatory (ESO) Very Large Telescope to confirm its redshift (z = 0.663 ± 0.001 based on the host-galaxy emission lines) and likely spectral type (type I). Using this redshift, we find MpeakU = –21.05+0.10–0.09 for the peak, rest-frame U-band absolute magnitude, and find DES13S2cmm to be located in a faint, low-metallicity (sub-solar), low stellar-mass hostmore » galaxy (log(M/M⊙) = 9.3 ± 0.3), consistent with what is seen for other SLSNe-I. We compare the bolometric light curve of DES13S2cmm to fourteen similarly well-observed SLSNe-I in the literature and find it possesses one of the slowest declining tails (beyond +30 days rest frame past peak), and is the faintest at peak. Moreover, we find the bolometric light curves of all SLSNe-I studied herein possess a dispersion of only 0.2–0.3 magnitudes between +25 and +30 days after peak (rest frame) depending on redshift range studied; this could be important for ‘standardising’ such supernovae, as is done with the more common type Ia. We fit the bolometric light curve of DES13S2cmm with two competing models for SLSNe-I – the radioactive decay of ⁵⁶Ni, and a magnetar – and find that while the magnetar is formally a better fit, neither model provides a compelling match to the data. Although we are unable to conclusively differentiate between these two physical models for this particular SLSN-I, further DES observations of more SLSNe-I should break this degeneracy, especially if the light curves of SLSNe-I can be observed beyond 100 days in the rest frame of the supernova.« less

  13. DES13S2cmm: The first superluminous supernova from the Dark Energy Survey

    SciTech Connect (OSTI)

    Papadopoulos, A.; Plazas, A. A.; D"Andrea, C. B.; Sullivan, M.; Nichol, R. C.; Barbary, K.; Biswas, R.; Brown, P. J.; Covarrubias, R. A.; Finley, D. A.; Fischer, J. A.; Foley, R. J.; Goldstein, D.; Gupta, R. R.; Kessler, R.; Kovacs, E.; Kuhlmann, S. E.; Lidman, C.; March, M.; Nugent, P. E.; Sako, M.; Smith, R. C.; Spinka, H.; Wester, W.; Abbott, T. M. C.; Abdalla, F.; Allam, S. S.; Banerji, M.; Bernstein, J. P.; Bernstein, R. A.; Carnero, A.; da Costa, L. N.; DePoy, D. L.; Desai, S.; Diehl, H. T.; Eifler, T.; Evrard, A. E.; Flaugher, B.; Frieman, J. A.; Gerdes, D.; Gruen, D.; Honscheid, K.; James, D.; Kuehn, K.; Kuropatkin, N.; Lahav, O.; Maia, M. A. G.; Makler, M.; Marshall, J. L.; Merritt, K. W.; Miller, C. J.; Miquel, R.; Ogando, R.; Roe, N. A.; Romer, A. K.; Rykoff, E.; Sanchez, E.; Santiago, B. X.; Scarpine, V.; Schubnell, M.; Sevilla, I.; Soares-Santos, M.; Suchyta, E.; Swanson, M.; Tarle, G.; Thaler, J.; Tucker, L. D.; Wechsler, R. H.; Zuntz, J.

    2015-03-23

    We present DES13S2cmm, the first spectroscopically-confirmed superluminous supernova (SLSN) from the Dark Energy Survey (DES). We briefly discuss the data and search algorithm used to find this event in the first year of DES operations, and outline the spectroscopic data obtained from the European Southern Observatory (ESO) Very Large Telescope to confirm its redshift (z = 0.663 ± 0.001 based on the host-galaxy emission lines) and likely spectral type (type I). Using this redshift, we find MpeakU = –21.05+0.10–0.09 for the peak, rest-frame U-band absolute magnitude, and find DES13S2cmm to be located in a faint, low-metallicity (sub-solar), low stellar-mass host galaxy (log(M/M⊙) = 9.3 ± 0.3), consistent with what is seen for other SLSNe-I. We compare the bolometric light curve of DES13S2cmm to fourteen similarly well-observed SLSNe-I in the literature and find it possesses one of the slowest declining tails (beyond +30 days rest frame past peak), and is the faintest at peak. Moreover, we find the bolometric light curves of all SLSNe-I studied herein possess a dispersion of only 0.2–0.3 magnitudes between +25 and +30 days after peak (rest frame) depending on redshift range studied; this could be important for ‘standardising’ such supernovae, as is done with the more common type Ia. We fit the bolometric light curve of DES13S2cmm with two competing models for SLSNe-I – the radioactive decay of ⁵⁶Ni, and a magnetar – and find that while the magnetar is formally a better fit, neither model provides a compelling match to the data. Although we are unable to conclusively differentiate between these two physical models for this particular SLSN-I, further DES observations of more SLSNe-I should break this degeneracy, especially if the light curves of SLSNe-I can be observed beyond 100 days in the rest frame of the supernova.

  14. DES13S2cmm: The first superluminous supernova from the dark energy survey

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Papadopoulos, A.; D'Andrea, C. B.; Sullivan, M.; Nichol, R. C.; Barbary, K.; Biswas, R.; Brown, P. J.; Covarrubias, R. A.; Finley, D. A.; Fischer, J. A.; et al

    2015-03-23

    We present DES13S2cmm, the first spectroscopically-confirmed superluminous supernova (SLSN) from the Dark Energy Survey (DES). We briefly discuss the data and search algorithm used to find this event in the first year of DES operations, and outline the spectroscopic data obtained from the European Southern Observatory (ESO) Very Large Telescope to confirm its redshift (z = 0.663 0.001 based on the host-galaxy emission lines) and likely spectral type (type I). Using this redshift, we find MUpeak = -21.05????-0.09 for the peak, rest-frame U-band absolute magnitude, and find DES13S2cmm to be located in a faint, low metallicity (sub-solar), low stellar-massmorehost galaxy (log(M/M_sun) = 9.3 0.3); consistent with what is seen for other SLSNe-I. We compare the bolometric light curve of DES13S2cmm to fourteen similarly well-observed SLSNe-I in the literature and find it possesses one of the slowest declining tails (beyond +30 days rest frame past peak), and is the faintest at peak. Moreover, we find the bolometric light curves of all SLSNe-I studied herein possess a dispersion of only 0.2-0.3 magnitudes between +25 and +30 days after peak (rest frame) depending on redshift range studied; this could be important for 'standardising' such supernovae, as is done with the more common type Ia. We fit the bolometric light curve of DES13S2cmm with two competing models for SLSNe-I - the radioactive decay of ??Ni, and a magnetar - and find that while the magnetar is formally a better fit, neither model provides a compelling match to the data. Although we are unable to conclusively differentiate between these two physical models for this particular SLSN-I, further DES observations of more SLSNe-I should break this degeneracy, especially if the light curves of SLSNe-I can be observed beyond 100 days in the rest frame of the supernova.less

  15. DES13S2cmm: The first superluminous supernova from the Dark Energy Survey

    SciTech Connect (OSTI)

    Papadopoulos, A.; Plazas, A. A.; D"Andrea, C. B.; Sullivan, M.; Nichol, R. C.; Barbary, K.; Biswas, R.; Brown, P. J.; Covarrubias, R. A.; Finley, D. A.; Fischer, J. A.; Foley, R. J.; Goldstein, D.; Gupta, R. R.; Kessler, R.; Kovacs, E.; Kuhlmann, S. E.; Lidman, C.; March, M.; Nugent, P. E.; Sako, M.; Smith, R. C.; Spinka, H.; Wester, W.; Abbott, T. M. C.; Abdalla, F.; Allam, S. S.; Banerji, M.; Bernstein, J. P.; Bernstein, R. A.; Carnero, A.; da Costa, L. N.; DePoy, D. L.; Desai, S.; Diehl, H. T.; Eifler, T.; Evrard, A. E.; Flaugher, B.; Frieman, J. A.; Gerdes, D.; Gruen, D.; Honscheid, K.; James, D.; Kuehn, K.; Kuropatkin, N.; Lahav, O.; Maia, M. A. G.; Makler, M.; Marshall, J. L.; Merritt, K. W.; Miller, C. J.; Miquel, R.; Ogando, R.; Roe, N. A.; Romer, A. K.; Rykoff, E.; Sanchez, E.; Santiago, B. X.; Scarpine, V.; Schubnell, M.; Sevilla, I.; Soares-Santos, M.; Suchyta, E.; Swanson, M.; Tarle, G.; Thaler, J.; Tucker, L. D.; Wechsler, R. H.; Zuntz, J.

    2015-03-23

    We present DES13S2cmm, the first spectroscopically-confirmed superluminous supernova (SLSN) from the Dark Energy Survey (DES). We briefly discuss the data and search algorithm used to find this event in the first year of DES operations, and outline the spectroscopic data obtained from the European Southern Observatory (ESO) Very Large Telescope to confirm its redshift (z = 0.663 0.001 based on the host-galaxy emission lines) and likely spectral type (type I). Using this redshift, we find MpeakU = 21.05+0.100.09 for the peak, rest-frame U-band absolute magnitude, and find DES13S2cmm to be located in a faint, low-metallicity (sub-solar), low stellar-mass host galaxy (log(M/M?) = 9.3 0.3), consistent with what is seen for other SLSNe-I. We compare the bolometric light curve of DES13S2cmm to fourteen similarly well-observed SLSNe-I in the literature and find it possesses one of the slowest declining tails (beyond +30 days rest frame past peak), and is the faintest at peak. Moreover, we find the bolometric light curves of all SLSNe-I studied herein possess a dispersion of only 0.20.3 magnitudes between +25 and +30 days after peak (rest frame) depending on redshift range studied; this could be important for standardising such supernovae, as is done with the more common type Ia. We fit the bolometric light curve of DES13S2cmm with two competing models for SLSNe-I the radioactive decay of ??Ni, and a magnetar and find that while the magnetar is formally a better fit, neither model provides a compelling match to the data. Although we are unable to conclusively differentiate between these two physical models for this particular SLSN-I, further DES observations of more SLSNe-I should break this degeneracy, especially if the light curves of SLSNe-I can be observed beyond 100 days in the rest frame of the supernova.

  16. Redshift Distributions of Galaxies in the DES Science Verification Shear Catalogue and Implications for Weak Lensing

    SciTech Connect (OSTI)

    Bonnett, C.

    2015-07-21

    We present photometric redshift estimates for galaxies used in the weak lensing analysis of the Dark Energy Survey Science Verification (DES SV) data. Four model- or machine learning-based photometric redshift methods { annz2, bpz calibrated against BCC-U fig simulations, skynet, and tpz { are analysed. For training, calibration, and testing of these methods, we also construct a catalogue of spectroscopically confirmed galaxies matched against DES SV data. The performance of the methods is evalu-ated against the matched spectroscopic catalogue, focusing on metrics relevant for weak lensing analyses, with additional validation against COSMOS photo-zs. From the galaxies in the DES SV shear catalogue, which have mean redshift 0.72 0.01 over the range 0:3 < z < 1:3, we construct three tomographic bins with means of z = {0.45; 0.67,1.00g}. These bins each have systematic uncertainties ?z ? 0.05 in the mean of the fiducial skynet photo-z n(z). We propagate the errors in the redshift distributions through to their impact on cosmological parameters estimated with cosmic shear, and find that they cause shifts in the value of ?8 of approx. 3%. This shift is within the one sigma statistical errors on ?8 for the DES SV shear catalog. We also found that further study of the potential impact of systematic differences on the critical surface density, ?crit, contained levels of bias safely less than the statistical power of DES SV data. We recommend a final Gaussian prior for the photo-z bias in the mean of n(z) of width 0:05 for each of the three tomographic bins, and show that this is a sufficient bias model for the corresponding cosmology analysis.

  17. Cross-correlation of gravitational lensing from DES Science Verification data with SPT and Planck lensing

    SciTech Connect (OSTI)

    Kirk, D.; et al.

    2015-12-14

    We measure the cross-correlation between weak lensing of galaxy images and of the cosmic microwave background (CMB). The effects of gravitational lensing on different sources will be correlated if the lensing is caused by the same mass fluctuations. We use galaxy shape measurements from 139 deg$^{2}$ of the Dark Energy Survey (DES) Science Verification data and overlapping CMB lensing from the South Pole Telescope (SPT) and Planck. The DES source galaxies have a median redshift of $z_{\\rm med} {\\sim} 0.7$, while the CMB lensing kernel is broad and peaks at $z{\\sim}2$. The resulting cross-correlation is maximally sensitive to mass fluctuations at $z{\\sim}0.44$. Assuming the Planck 2015 best-fit cosmology, the amplitude of the DES$\\times$SPT cross-power is found to be $A = 0.88 \\pm 0.30$ and that from DES$\\times$Planck to be $A = 0.86 \\pm 0.39$, where $A=1$ corresponds to the theoretical prediction. These are consistent with the expected signal and correspond to significances of $2.9 \\sigma$ and $2.2 \\sigma$ respectively. We demonstrate that our results are robust to a number of important systematic effects including the shear measurement method, estimator choice, photometric redshift uncertainty and CMB lensing systematics. Significant intrinsic alignment of galaxy shapes would increase the cross-correlation signal inferred from the data; we calculate a value of $A = 1.08 \\pm 0.36$ for DES$\\times$SPT when we correct the observations with a simple IA model. With three measurements of this cross-correlation now existing in the literature, there is not yet reliable evidence for any deviation from the expected LCDM level of cross-correlation, given the size of the statistical uncertainties and the significant impact of systematic errors, particularly IAs. We provide forecasts for the expected signal-to-noise of the combination of the five-year DES survey and SPT-3G.

  18. Mapping and Simulating Systematics Due to Spatially-Varying Observing Conditions in DES Science Verification Data

    SciTech Connect (OSTI)

    Leistedt, B.

    2015-07-20

    Spatially-varying depth and characteristics of observing conditions, such as seeing, airmass, or sky background, are major sources of systematic uncertainties in modern galaxy survey analyses, in particular in deep multi-epoch surveys. We present a framework to extract and project these sources of systematics onto the sky, and apply it to the Dark Energy Survey (DES) to map the observing conditions of the Science Verification (SV) data. The resulting distributions and maps of sources of systematics are used in several analyses of DES SV to perform detailed null tests with the data, and also to incorporate systematics in survey simulations. We illustrate the complementarity of these two approaches by comparing the SV data with the BCC-UFig, a synthetic sky catalogue generated by forward-modelling of the DES SV images. We then analyse the BCC-UFig simulation to construct galaxy samples mimicking those used in SV galaxy clustering studies. We show that the spatially-varying survey depth imprinted in the observed galaxy densities and the redshift distributions of the SV data are successfully reproduced by the simulation and well-captured by the maps of observing conditions. The combined use of the maps, the SV data and the BCC-UFig simulation allows us to quantify the impact of spatial systematics on N(z), the redshift distributions inferred using photometric redshifts. We conclude that spatial systematics in the SV data are mainly due to seeing fluctuations and are under control in current clustering and weak lensing analyses. However, they will need to be carefully characterised in upcoming phases of DES in order to avoid biasing the inferred cosmological results. The framework presented is relevant to all multi-epoch surveys, and will be essential for exploiting future surveys such as the Large Synoptic Survey Telescope, which will require detailed null-tests and realistic end-to-end image simulations to correctly interpret the deep, high-cadence observations of the

  19. The LMC geometry and outer stellar populations from early DES data

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Balbinot, Eduardo; Plazas, A.; Santiago, B. X.; Girardi, L.; Pieres, A.; da Costa, L. N.; Maia, M. A. G.; Gruendl, R. A.; Walker, A. R.; Yanny, B.; et al

    2015-03-20

    The Dark Energy Camera has captured a large set of images as part of Science Verification (SV) for the Dark Energy Survey. The SV footprint covers a large portion of the outer Large Magellanic Cloud (LMC), providing photometry 1.5 magnitudes fainter than the main sequence turn-off of the oldest LMC stellar population. We derive geometrical and structural parameters for various stellar populations in the LMC disc. For the distribution of all LMC stars, we find an inclination of i = –38.14°±0.08° (near side in the North) and a position angle for the line of nodes of θ₀ = 129.51°±0.17°. Wemore » find that stars younger than ~4 Gyr are more centrally concentrated than older stars. Fitting a projected exponential disc shows that the scale radius of the old populations is R>4Gyr = 1.41 ± 0.01 kpc, while the younger population has R<4Gyr = 0.72 ± 0.01 kpc. However, the spatial distribution of the younger population deviates significantly from the projected exponential disc model. The distribution of old stars suggests a large truncation radius of Rt = 13.5 ± 0.8 kpc. If this truncation is dominated by the tidal field of the Galaxy, we find that the LMC is ≃24+9–6 times less massive than the encircled Galactic mass. By measuring the Red Clump peak magnitude and comparing with the best-fit LMC disc model, we find that the LMC disc is warped and thicker in the outer regions north of the LMC centre. As a result, our findings may either be interpreted as a warped and flared disc in the LMC outskirts, or as evidence of a spheroidal halo component.« less

  20. The LMC geometry and outer stellar populations from early DES data

    SciTech Connect (OSTI)

    Balbinot, Eduardo; Plazas, A.; Santiago, B. X.; Girardi, L.; Pieres, A.; da Costa, L. N.; Maia, M. A. G.; Gruendl, R. A.; Walker, A. R.; Yanny, B.; Drlica-Wagner, A.; Benoit-Levy, A.; Abbott, T. M. C.; Allam, S. S.; Annis, J.; Bernstein, J. P.; Bernstein, R. A.; Bertin, E.; Brooks, D.; Buckley-Geer, E.; Rosell, A. Carnero; Cunha, C. E.; Depoy, D. L.; Desai, S.; Diehl, H. T.; Doel, P.; Estrada, J.; Evrard, A. E.; Fausti Neto, A.; Finley, D. A.; Flaugher, B.; Frieman, J. A.; Gruen, D.; Honscheid, K.; James, D.; Kuehn, K.; Kuropatkin, N.; Lahav, O.; March, M.; Marshall, J. L.; Miller, C.; Miquel, R.; Ogando, R.; Peoples, J.; Scarpine, V.; Schubnell, M.; Sevilla-Noarbe, I.; Smith, R. C.; Soares-Santos, M.; Suchyta, E.; Swanson, M. E. C.; Tarle, G.; Tucker, D. L.; Wechsler, R.; Zuntz, J.

    2015-03-20

    The Dark Energy Camera has captured a large set of images as part of Science Verification (SV) for the Dark Energy Survey. The SV footprint covers a large portion of the outer Large Magellanic Cloud (LMC), providing photometry 1.5 magnitudes fainter than the main sequence turn-off of the oldest LMC stellar population. We derive geometrical and structural parameters for various stellar populations in the LMC disc. For the distribution of all LMC stars, we find an inclination of i = –38.14°±0.08° (near side in the North) and a position angle for the line of nodes of θ₀ = 129.51°±0.17°. We find that stars younger than ~4 Gyr are more centrally concentrated than older stars. Fitting a projected exponential disc shows that the scale radius of the old populations is R>4Gyr = 1.41 ± 0.01 kpc, while the younger population has R<4Gyr = 0.72 ± 0.01 kpc. However, the spatial distribution of the younger population deviates significantly from the projected exponential disc model. The distribution of old stars suggests a large truncation radius of Rt = 13.5 ± 0.8 kpc. If this truncation is dominated by the tidal field of the Galaxy, we find that the LMC is ≃24+9–6 times less massive than the encircled Galactic mass. By measuring the Red Clump peak magnitude and comparing with the best-fit LMC disc model, we find that the LMC disc is warped and thicker in the outer regions north of the LMC centre. As a result, our findings may either be interpreted as a warped and flared disc in the LMC outskirts, or as evidence of a spheroidal halo component.

  1. The LMC geometry and outer stellar populations from early DES data

    SciTech Connect (OSTI)

    Balbinot, Eduardo; Plazas, A.; Santiago, B. X.; Girardi, L.; Pieres, A.; da Costa, L. N.; Maia, M. A. G.; Gruendl, R. A.; Walker, A. R.; Yanny, B.; Drlica-Wagner, A.; Benoit-Levy, A.; Abbott, T. M. C.; Allam, S. S.; Annis, J.; Bernstein, J. P.; Bernstein, R. A.; Bertin, E.; Brooks, D.; Buckley-Geer, E.; Rosell, A. Carnero; Cunha, C. E.; Depoy, D. L.; Desai, S.; Diehl, H. T.; Doel, P.; Estrada, J.; Evrard, A. E.; Fausti Neto, A.; Finley, D. A.; Flaugher, B.; Frieman, J. A.; Gruen, D.; Honscheid, K.; James, D.; Kuehn, K.; Kuropatkin, N.; Lahav, O.; March, M.; Marshall, J. L.; Miller, C.; Miquel, R.; Ogando, R.; Peoples, J.; Scarpine, V.; Schubnell, M.; Sevilla-Noarbe, I.; Smith, R. C.; Soares-Santos, M.; Suchyta, E.; Swanson, M. E. C.; Tarle, G.; Tucker, D. L.; Wechsler, R.; Zuntz, J.

    2015-03-20

    The Dark Energy Camera has captured a large set of images as part of Science Verification (SV) for the Dark Energy Survey. The SV footprint covers a large portion of the outer Large Magellanic Cloud (LMC), providing photometry 1.5 magnitudes fainter than the main sequence turn-off of the oldest LMC stellar population. We derive geometrical and structural parameters for various stellar populations in the LMC disc. For the distribution of all LMC stars, we find an inclination of i = 38.140.08 (near side in the North) and a position angle for the line of nodes of ?? = 129.510.17. We find that stars younger than ~4 Gyr are more centrally concentrated than older stars. Fitting a projected exponential disc shows that the scale radius of the old populations is R>4Gyr = 1.41 0.01 kpc, while the younger population has R<4Gyr = 0.72 0.01 kpc. However, the spatial distribution of the younger population deviates significantly from the projected exponential disc model. The distribution of old stars suggests a large truncation radius of Rt = 13.5 0.8 kpc. If this truncation is dominated by the tidal field of the Galaxy, we find that the LMC is ?24+96 times less massive than the encircled Galactic mass. By measuring the Red Clump peak magnitude and comparing with the best-fit LMC disc model, we find that the LMC disc is warped and thicker in the outer regions north of the LMC centre. As a result, our findings may either be interpreted as a warped and flared disc in the LMC outskirts, or as evidence of a spheroidal halo component.

  2. Magellan Tackles the Mysterious Proton Spin

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    of NERSC, ACLF and ESnet to run on the cloud. From this work we learned that scientific cloud computing is more than just about processing data. It's a whole environment that...

  3. Photometric redshifts and clustering of emission line galaxies selected jointly by DES and eBOSS

    SciTech Connect (OSTI)

    Jouvel, S.; et al.

    2015-09-23

    We present the results of the first test plates of the extended Baryon Oscillation Spectroscopic Survey. This paper focuses on the emission line galaxies (ELG) population targetted from the Dark Energy Survey (DES) photometry. We analyse the success rate, efficiency, redshift distribution, and clustering properties of the targets. From the 9000 spectroscopic redshifts targetted, 4600 have been selected from the DES photometry. The total success rate for redshifts between 0.6 and 1.2 is 71\\% and 68\\% respectively for a bright and faint, on average more distant, samples including redshifts measured from a single strong emission line. We find a mean redshift of 0.8 and 0.87, with 15 and 13\\% of unknown redshifts respectively for the bright and faint samples. In the redshift range 0.6DES photometric redshifts and find that the outlier fraction can be reduced using a comparison between template fitting and neural network, or using a random forest algorithm.

  4. OzDES multifibre spectroscopy for the Dark Energy Survey: First-year operation and results

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Yuan, Fang; Plazas, A. A.; Lidman, C.; Davis, T. M.; Childress, M.; Abdalla, F. B.

    2015-07-29

    OzDES is a five-year, 100-night, spectroscopic survey on the Anglo-Australian Telescope, whose primary aim is to measure redshifts of approximately 2,500 Type Ia supernovae host galaxies over the redshift range 0.1 morehelp calibrate photometric redshifts. Here we present an overview of the OzDES program and our first-year results. Between Dec 2012 and Dec 2013, we observed over 10,000 objects and measured more than 6,000 redshifts. Our strategy of retargeting faint objects across many observing runs has allowed us to measure redshifts for galaxies as faint as mr = 25 mag. We outline our target selection and observing strategy, quantify the redshift success rate for different types of targets, and discuss the implications for our main science goals. Finally, we highlight a few interesting objects as examples of the fortuitous yet not totally unexpected discoveries that can come from such a large spectroscopic survey.less

  5. OzDES multifibre spectroscopy for the Dark Energy Survey: First-year operation and results

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Yuan, Fang

    2015-07-29

    The Australian Dark Energy Survey (OzDES) is a five-year, 100-night, spectroscopic survey on the Anglo-Australian Telescope, whose primary aim is to measure redshifts of approximately 2500 Type Ia supernovae host galaxies over the redshift range 0.1 < z < 1.2, and derive reverberation-mapped black hole masses for approximately 500 active galactic nuclei and quasars over 0.3 < z < 4.5. This treasure trove of data forms a major part of the spectroscopic follow-up for the Dark Energy Survey for which we are also targeting cluster galaxies, radio galaxies, strong lenses, and unidentified transients, as well as measuring luminous red galaxiesmore » and emission line galaxies to help calibrate photometric redshifts. Here, we present an overview of the OzDES programme and our first-year results. Between 2012 December and 2013 December, we observed over 10 000 objects and measured more than 6 000 redshifts. Our strategy of retargeting faint objects across many observing runs has allowed us to measure redshifts for galaxies as faint as mr = 25 mag. We outline our target selection and observing strategy, quantify the redshift success rate for different types of targets, and discuss the implications for our main science goals. In conclusion, we highlight a few interesting objects as examples of the fortuitous yet not totally unexpected discoveries that can come from such a large spectroscopic survey.« less

  6. Joint Analysis of Galaxy-Galaxy Lensing and Galaxy Clustering: Methodology and Forecasts for DES

    SciTech Connect (OSTI)

    Park, Y.

    2015-07-19

    The joint analysis of galaxy-galaxy lensing and galaxy clustering is a promising method for inferring the growth function of large scale structure. Our analysis will be carried out on data from the Dark Energy Survey (DES), with its measurements of both the distribution of galaxies and the tangential shears of background galaxies induced by these foreground lenses. We develop a practical approach to modeling the assumptions and systematic effects affecting small scale lensing, which provides halo masses, and large scale galaxy clustering. Introducing parameters that characterize the halo occupation distribution (HOD), photometric redshift uncertainties, and shear measurement errors, we study how external priors on different subsets of these parameters affect our growth constraints. Degeneracies within the HOD model, as well as between the HOD and the growth function, are identified as the dominant source of complication, with other systematic effects sub-dominant. The impact of HOD parameters and their degeneracies necessitate the detailed joint modeling of the galaxy sample that we employ. Finally, we conclude that DES data will provide powerful constraints on the evolution of structure growth in the universe, conservatively/optimistically constraining the growth function to 7.9%/4.8% with its first-year data that covered over 1000 square degrees, and to 3.9%/2.3% with its full five-year data that will survey 5000 square degrees, including both statistical and systematic uncertainties.

  7. OzDES multifibre spectroscopy for the Dark Energy Survey: First-year operation and results

    SciTech Connect (OSTI)

    Yuan, Fang

    2015-07-29

    The Australian Dark Energy Survey (OzDES) is a five-year, 100-night, spectroscopic survey on the Anglo-Australian Telescope, whose primary aim is to measure redshifts of approximately 2500 Type Ia supernovae host galaxies over the redshift range 0.1 < z < 1.2, and derive reverberation-mapped black hole masses for approximately 500 active galactic nuclei and quasars over 0.3 < z < 4.5. This treasure trove of data forms a major part of the spectroscopic follow-up for the Dark Energy Survey for which we are also targeting cluster galaxies, radio galaxies, strong lenses, and unidentified transients, as well as measuring luminous red galaxies and emission line galaxies to help calibrate photometric redshifts. Here, we present an overview of the OzDES programme and our first-year results. Between 2012 December and 2013 December, we observed over 10 000 objects and measured more than 6 000 redshifts. Our strategy of retargeting faint objects across many observing runs has allowed us to measure redshifts for galaxies as faint as mr = 25 mag. We outline our target selection and observing strategy, quantify the redshift success rate for different types of targets, and discuss the implications for our main science goals. In conclusion, we highlight a few interesting objects as examples of the fortuitous yet not totally unexpected discoveries that can come from such a large spectroscopic survey.

  8. DES14X3taz: A type I superluminous supernova showing a luminous, rapidly cooling initial pre-peak bump

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Smith, M.

    2016-02-03

    Here, we present DES14X3taz, a new hydrogen-poor superluminous supernova (SLSN-I) discovered by the Dark Energy Survey (DES) supernova program, with additional photometric data provided by the Survey Using DECam for Superluminous Supernovae. Spectra obtained using Optical System for Imaging and low-Intermediate-Resolution Integrated Spectroscopy on the Gran Telescopio CANARIAS show DES14X3taz is an SLSN-I at z = 0.608. Multi-color photometry reveals a double-peaked light curve: a blue and relatively bright initial peak that fades rapidly prior to the slower rise of the main light curve. Our multi-color photometry allows us, for the first time, to show that the initial peak cools from 22,000more » to 8000 K over 15 rest-frame days, and is faster and brighter than any published core-collapse supernova, reaching 30% of the bolometric luminosity of the main peak. No physical (56)Ni-powered model can fit this initial peak. We show that a shock-cooling model followed by a magnetar driving the second phase of the light curve can adequately explain the entire light curve of DES14X3taz. Models involving the shock-cooling of extended circumstellar material at a distance of ≃400 R⊙ are preferred over the cooling of shock-heated surface layers of a stellar envelope. We compare DES14X3taz to the few double-peaked SLSN-I events in the literature. Although the rise times and characteristics of these initial peaks differ, there exists the tantalizing possibility that they can be explained by one physical interpretation.« less

  9. Wide-Field Lensing Mass Maps from DES Science Verification Data

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Chang, C.; Vikram, V.; Jain, B.

    2015-07-29

    We present a mass map reconstructed from weak gravitational lensing shear measurements over 139 deg2 from the Dark Energy Survey (DES) Science Verification data. The mass map probes both luminous and dark matter, thus providing a tool for studying cosmology. We find good agreement between the mass map and the distribution of massive galaxy clusters identified using a red-sequence cluster finder. Potential candidates for super-clusters and voids are identified using these maps. We measure the cross-correlation between the mass map and a magnitude-limited foreground galaxy sample and find a detection at the 6.8? level with 20 arcminute smoothing. These measurementsmoreare consistent with simulated galaxy catalogs based on ?CDM Nbody simulations, suggesting low systematics uncertainties in the map. We summarize our key findings in this letter; the detailed methodology and tests for systematics are presented in a companion paper.less

  10. DES J0454–4448: Discovery of the first luminous z ≥ 6 quasar from the Dark Energy Survey

    SciTech Connect (OSTI)

    Reed, S. L.

    2015-10-28

    We present the first results of a survey for high-redshift, z ≥ 6, quasars using izY multicolour photometric observations from the Dark Energy Survey (DES). Here we report the discovery and spectroscopic confirmation of the zAB, YAB = 20.2, 20.2 (M1450 = –26.5) quasar DES J0454–4448 with a redshift of z = 6.09±0.02 based on the onset of the Ly α forest and an H i near zone size of 4.1+1.1–1.2 proper Mpc. The quasar was selected as an i-band drop out with i–z = 2.46 and zAB < 21.5 from an area of ~300 deg2. It is the brightest of our 43 candidates and was identified for spectroscopic follow-up solely based on the DES i–z and z–Y colours. The quasar is detected by WISE and has W1AB = 19.68. The discovery of one spectroscopically confirmed quasar with 5.7 < z < 6.5 and zAB ≤ 20.2 is consistent with recent determinations of the luminosity function at z ~ 6. DES when completed will have imaged ~5000 deg2 to YAB = 23.0 (5σ point source) and we expect to discover 50–100 new quasars with z > 6 including 3–10 with z > 7 dramatically increasing the numbers of quasars currently known that are suitable for detailed studies.

  11. DES J0454–4448: Discovery of the first luminous z ≥ 6 quasar from the Dark Energy Survey

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Reed, S. L.

    2015-10-28

    We present the first results of a survey for high-redshift, z ≥ 6, quasars using izY multicolour photometric observations from the Dark Energy Survey (DES). Here we report the discovery and spectroscopic confirmation of the zAB, YAB = 20.2, 20.2 (M1450 = –26.5) quasar DES J0454–4448 with a redshift of z = 6.09±0.02 based on the onset of the Ly α forest and an H i near zone size of 4.1+1.1–1.2 proper Mpc. The quasar was selected as an i-band drop out with i–z = 2.46 and zAB < 21.5 from an area of ~300 deg2. It is the brightestmore » of our 43 candidates and was identified for spectroscopic follow-up solely based on the DES i–z and z–Y colours. The quasar is detected by WISE and has W1AB = 19.68. The discovery of one spectroscopically confirmed quasar with 5.7 < z < 6.5 and zAB ≤ 20.2 is consistent with recent determinations of the luminosity function at z ~ 6. DES when completed will have imaged ~5000 deg2 to YAB = 23.0 (5σ point source) and we expect to discover 50–100 new quasars with z > 6 including 3–10 with z > 7 dramatically increasing the numbers of quasars currently known that are suitable for detailed studies.« less

  12. redMaGiC. Selecting Luminous Red Galaxies from the DES Science Verification Data

    SciTech Connect (OSTI)

    Rozo, E.

    2015-07-20

    We introduce redMaGiC, an automated algorithm for selecting Luminous Red Galaxies (LRGs). The algorithm was developed to minimize photometric redshift uncertainties in photometric large-scale structure studies. redMaGiC achieves this by self-training the color-cuts necessary to produce a luminosity-thresholded LRG sam- ple of constant comoving density. Additionally, we demonstrate that redMaGiC photo-zs are very nearly as accurate as the best machine-learning based methods, yet they require minimal spectroscopic training, do not suffer from extrapolation biases, and are very nearly Gaussian. We apply our algorithm to Dark Energy Survey (DES) Science Verification (SV) data to produce a redMaGiC catalog sampling the redshift range z ϵ [0.2,0.8]. Our fiducial sample has a comoving space density of 10-3 (h-1Mpc)-3, and a median photo-z bias (zspec zphoto) and scatter (σz=(1 + z)) of 0.005 and 0.017 respectively.The corresponding 5σ outlier fraction is 1.4%. We also test our algorithm with Sloan Digital Sky Survey (SDSS) Data Release 8 (DR8) and Stripe 82 data, and discuss how spectroscopic training can be used to control photo-z biases at the 0.1% level.

  13. Galaxy Clustering, Photometric Redshifts and Diagnosis of Systematics in the DES Science Verification Data

    SciTech Connect (OSTI)

    Crocce, M.

    2015-12-09

    We study the clustering of galaxies detected at i < 22.5 in the Science Verification observations of the Dark Energy Survey (DES). Two-point correlation functions are measured using 2.3 × 106 galaxies over a contiguous 116 deg2 region in five bins of photometric redshift width Δz = 0.2 in the range 0.2 < z < 1.2. The impact of photometric redshift errors is assessed by comparing results using a template-based photo-zalgorithm (BPZ) to a machine-learning algorithm (TPZ). A companion paper presents maps of several observational variables (e.g. seeing, sky brightness) which could modulate the galaxy density. Here we characterize and mitigate systematic errors on the measured clustering which arise from these observational variables, in addition to others such as Galactic dust and stellar contamination. After correcting for systematic effects, we then measure galaxy bias over a broad range of linear scales relative to mass clustering predicted from the Planck Λ cold dark matter model, finding agreement with the Canada-France-Hawaii Telescope Legacy Survey (CFHTLS) measurements with χ2 of 4.0 (8.7) with 5 degrees of freedom for the TPZ (BPZ) redshifts. Furthermore, we test a ‘linear bias’ model, in which the galaxy clustering is a fixed multiple of the predicted non-linear dark matter clustering. The precision of the data allows us to determine that the linear bias model describes the observed galaxy clustering to 2.5 percent accuracy down to scales at least 4–10 times smaller than those on which linear theory is expected to be sufficient.

  14. Galaxy Clustering, Photometric Redshifts and Diagnosis of Systematics in the DES Science Verification Data

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Crocce, M.

    2015-12-09

    We study the clustering of galaxies detected at i < 22.5 in the Science Verification observations of the Dark Energy Survey (DES). Two-point correlation functions are measured using 2.3 × 106 galaxies over a contiguous 116 deg2 region in five bins of photometric redshift width Δz = 0.2 in the range 0.2 < z < 1.2. The impact of photometric redshift errors is assessed by comparing results using a template-based photo-zalgorithm (BPZ) to a machine-learning algorithm (TPZ). A companion paper presents maps of several observational variables (e.g. seeing, sky brightness) which could modulate the galaxy density. Here we characterize andmore » mitigate systematic errors on the measured clustering which arise from these observational variables, in addition to others such as Galactic dust and stellar contamination. After correcting for systematic effects, we then measure galaxy bias over a broad range of linear scales relative to mass clustering predicted from the Planck Λ cold dark matter model, finding agreement with the Canada-France-Hawaii Telescope Legacy Survey (CFHTLS) measurements with χ2 of 4.0 (8.7) with 5 degrees of freedom for the TPZ (BPZ) redshifts. Furthermore, we test a ‘linear bias’ model, in which the galaxy clustering is a fixed multiple of the predicted non-linear dark matter clustering. The precision of the data allows us to determine that the linear bias model describes the observed galaxy clustering to 2.5 percent accuracy down to scales at least 4–10 times smaller than those on which linear theory is expected to be sufficient.« less

  15. Search for Gamma-Ray Emission from DES Dwarf Spheroidal Galaxy Candidates with Fermi-LAT Data

    SciTech Connect (OSTI)

    Drlica-Wagner, A.; et al.

    2015-08-04

    Due to their proximity, high dark-matter (DM) content, and apparent absence of non-thermal processes, Milky Way dwarf spheroidal satellite galaxies (dSphs) are excellent targets for the indirect detection of DM. Recently, eight new dSph candidates were discovered using the first year of data from the Dark Energy Survey (DES). We searched for gamma-ray emission coincident with the positions of these new objects in six years of Fermi Large Area Telescope data. We found no significant excesses of gamma-ray emission. Under the assumption that the DES candidates are dSphs with DM halo properties similar to the known dSphs, we computed individual and combined limits on the velocity-averaged DM annihilation cross section for these new targets. If the estimated DM content of these dSph candidates is confirmed, they will constrain the annihilation cross section to lie below the thermal relic cross section for DM particles with masses $\\lesssim 20\\,\\mathrm{GeV}$ annihilating via the $b\\bar{b}$ or τ(+)τ(-) channels.

  16. How to Find Ames Laboratory | The Ames Laboratory

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    How to Find Ames Laboratory Finding the Ames Laboratory The Ames Laboratory has it's main administrative offices in the Technical and Administrative Services Facility (TASF) building on the Iowa State University Campus. Technical and Administrative Services Facility (TASF) 2408 Pammel Drive, Ames, IA 50011-1015 For directions from the Des Moines Airport please use the link with the following directions: https://goo.gl/maps/c6SOK Finding the Ames Laboratory on the ISU Campus Image Click on the

  17. DOE - Office of Legacy Management -- Iowa Army Ammunition Plant - IA 02

    Office of Legacy Management (LM)

    Army Ammunition Plant - IA 02 FUSRAP Considered Sites Iowa Army Ammunition Plant, IA Alternate Name(s): Burlington Ordnance Plant Iowa Ordnance Plant Silas Mason Company IA.02-3 Location: Located in Township 70 North, Range 3 West, Section 32, 5th Principal Meridian, Des Moines County, Burlington, Iowa IA.02-1 IA.02-5 Historical Operations: Assembled nuclear weapons, primarily high explosive components and conducted explosives testing using the high explosive components and depleted uranium. AEC

  18. Report on technical exchanges between CESTA and LLNL concerning FEL/induction activities; Bilan des exchanges techniques entre le CESTA et le LLNL sur les activites LEL/induction

    SciTech Connect (OSTI)

    Thevenot, M.; Eyl, P.

    1991-11-06

    Within the framework of scientific collaboration related to FEL (Free Electron Laser) activities between LLNL (Lawrence Livermore National Laboratory, USA) and CESTA [Centre d`Etudes des Systemes et des Technologies Avancees = Advanced Technology and Systems Research Center -- Tr. Ed.], the principal subject of these exchanges was the technology of high-voltage impulse generators designed to supply induction-type [linear] accelerators (LINAC). The role of this cooperative effort, which was to pool the expertise of the two laboratories, was not limited simply to an inspection of installations and methods. On the contrary, it permitted two representatives from each center to participate intimately in the experiments conducted on the experiments conducted on the LLNL equipment, and then at CESTA. 4 refs., 1 fig.

  19. Eight ultra-faint galaxy candidates discovered in year two of the Dark Energy Survey

    SciTech Connect (OSTI)

    Drlica-Wagner, A.

    2015-11-04

    We report the discovery of eight new ultra-faint dwarf galaxy candidates in the second year of optical imaging data from the Dark Energy Survey (DES). Six of these candidates are detected at high confidence, while two lower-confidence candidates are identified in regions of non-uniform survey coverage. The new stellar systems are found by three independent automated search techniques and are identified as overdensities of stars, consistent with the isochrone and luminosity function of an old and metal-poor simple stellar population. The new systems are faint (MV > -4.7 ) and span a range of physical sizes (17 pc < r1/2 < 181pc) and heliocentric distances (25 kpc < D < 214 kpc). All of the new systems have central surface brightnesses consistent with known ultra-faint dwarf galaxies (μ 27.5 mag arcsec -2). Roughly half of the DES candidates are more distant, less luminous, and/or have lower surface brightnesses than previously known Milky Way satellite galaxies. Most of the candidates are found in the southern part of the DES footprint close to the Magellanic Clouds. We find that the DES data alone exclude (p < 10-3) a spatially isotropic distribution of Milky Way satellites and that the observed distribution can be well, though not uniquely, described by an association between several of the DES satellites and the Magellanic system. Furthermore, our model predicts that the full sky may hold ~100 ultra-faint galaxies with physical properties comparable to the DES satellites and that 20%–30% of these would be spatially associated with the Magellanic Clouds.

  20. Eight ultra-faint galaxy candidates discovered in year two of the Dark Energy Survey

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Drlica-Wagner, A.

    2015-11-04

    We report the discovery of eight new ultra-faint dwarf galaxy candidates in the second year of optical imaging data from the Dark Energy Survey (DES). Six of these candidates are detected at high confidence, while two lower-confidence candidates are identified in regions of non-uniform survey coverage. The new stellar systems are found by three independent automated search techniques and are identified as overdensities of stars, consistent with the isochrone and luminosity function of an old and metal-poor simple stellar population. The new systems are faint (MV > -4.7 ) and span a range of physical sizes (17 pc < r1/2more » < 181pc) and heliocentric distances (25 kpc < D⊙ < 214 kpc). All of the new systems have central surface brightnesses consistent with known ultra-faint dwarf galaxies (μ 27.5 mag arcsec -2). Roughly half of the DES candidates are more distant, less luminous, and/or have lower surface brightnesses than previously known Milky Way satellite galaxies. Most of the candidates are found in the southern part of the DES footprint close to the Magellanic Clouds. We find that the DES data alone exclude (p < 10-3) a spatially isotropic distribution of Milky Way satellites and that the observed distribution can be well, though not uniquely, described by an association between several of the DES satellites and the Magellanic system. Furthermore, our model predicts that the full sky may hold ~100 ultra-faint galaxies with physical properties comparable to the DES satellites and that 20%–30% of these would be spatially associated with the Magellanic Clouds.« less

  1. Identification of amino-acid residues in the V protein of peste des petits ruminants essential for interference and suppression of STAT-mediated interferon signaling

    SciTech Connect (OSTI)

    Ma, Xusheng; Yang, Xing; Nian, Xiaofeng; Zhang, Zhidong; Dou, Yongxi; Zhang, Xuehu; Luo, Xuenong; Su, Junhong; Zhu, Qiyun; Cai, Xuepeng

    2015-09-15

    Peste des petits ruminants virus (PPRV) causes a fatal disease in small ruminants. V protein of PPRV plays a pivotal role in interfering with host innate immunity by blocking IFNs signaling through interacting with STAT1 and STAT2. In the present study, the results demonstrated that PPRV V protein blocks IFN actions in a dose dependent manner and restrains the translocation of STAT1/2 proteins. We speculate that the translocation inhibition might be caused by the interfering of the downstream of STAT protein. Mutagenesis defines that Cys cluster and Trp motif of PPRV V protein are essential for STAT-mediated IFN signaling. These findings give a new sight for the further studies to understand the delicate mechanism of PPRV to escape the IFN signaling. - Highlights: • PPRV V protein inhibits type I IFN production and blocks its activation. • PPRV V protein negatively regulates activation of ISRE and GAS promoter. • PPRV V protein inhibits nuclear translocation of STAT protein by non-degradation. • PNT and VCT domain of PPRV V protein inhibit IFN transduction. • PPRV V protein binds with STAT protein via some conserved motifs.

  2. 2015HSSB Resultsbracket

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    13 21 3 4 14 5 6 15 22 7 8 16 27 9 10 11 12 L 15 23 L 16 18 L 13 19 L 14 20 24 17 L 21 25 L 22 26 28 L 27 29 30 CHAMPIONSHIP Champion ______________________ Runner-up _______________________ Third Place ____________________________ Fourth Place ___________________________ Challenger Bracket Undefeated Bracket Science Bowl 2016 Double Elimination Competition Central Lee #2 Prince of Peace (withdrew) Valley 94 Ames 50 Grinnell 52 Shenandoah 26 Des Moines Central 78 Lynnville-Sully 8 Boyer Valley

  3. Discovery of two gravitationally lensed quasars in the Dark Energy Survey

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Agnello, A.

    2015-10-01

    In this study, we present spectroscopic confirmation of two new lensed quasars via data obtained at the 6.5m Magellan/Baade Telescope. The lens candidates have been selected from the Dark Energy Survey (DES) and WISE based on their multi-band photometry and extended morphology in DES images. Images of DES J0115-5244 show two blue point sources at either side of a red galaxy. Our long-slit data confirm that both point sources are images of the same quasar at zs = 1.64. The Einstein Radius estimated from the DES images is 0.51''. DES J2146-0047 is in the area of overlap between DES andmore » the Sloan Digital Sky Survey (SDSS). Two blue components are visible in the DES and SDSS images. The SDSS fiber spectrum shows a quasar component at zs = 2.38 and absorption compatible with Mg II and Fe II at zl = 0.799, which we tentatively associate with the foreground lens galaxy. The long-slit Magellan spectra show that the blue components are resolved images of the same quasar. Furthermore, the Einstein Radius is 0.68'' corresponding to an enclosed mass of 1.6 × 1011 M⊙. Three other candidates were observed and rejected, two being low-redshift pairs of starburst galaxies, and one being a quasar behind a blue star. These first confirmation results provide an important empirical validation of the data-mining and model-based selection that is being applied to the entire DES dataset.« less

  4. Discovery of two gravitationally lensed quasars in the Dark Energy Survey

    SciTech Connect (OSTI)

    Agnello, A.

    2015-10-01

    In this study, we present spectroscopic confirmation of two new lensed quasars via data obtained at the 6.5m Magellan/Baade Telescope. The lens candidates have been selected from the Dark Energy Survey (DES) and WISE based on their multi-band photometry and extended morphology in DES images. Images of DES J0115-5244 show two blue point sources at either side of a red galaxy. Our long-slit data confirm that both point sources are images of the same quasar at zs = 1.64. The Einstein Radius estimated from the DES images is 0.51''. DES J2146-0047 is in the area of overlap between DES and the Sloan Digital Sky Survey (SDSS). Two blue components are visible in the DES and SDSS images. The SDSS fiber spectrum shows a quasar component at zs = 2.38 and absorption compatible with Mg II and Fe II at zl = 0.799, which we tentatively associate with the foreground lens galaxy. The long-slit Magellan spectra show that the blue components are resolved images of the same quasar. Furthermore, the Einstein Radius is 0.68'' corresponding to an enclosed mass of 1.6 1011 M?. Three other candidates were observed and rejected, two being low-redshift pairs of starburst galaxies, and one being a quasar behind a blue star. These first confirmation results provide an important empirical validation of the data-mining and model-based selection that is being applied to the entire DES dataset.

  5. Comparison of effectiveness of sub-slab ventilation systems for indoor radon mitigation: A numerical study; Comparaison a l`aide d`un outil numerique de l`efficacite des systemes de ventilation active du sol limitant la penetration du radon dans l`habitat

    SciTech Connect (OSTI)

    Bonnefous, Y.C. |; Gadgil, A.J.; Allard, F.

    1992-04-01

    The functioning of an active sub-slab ventilation system (SVS) has been studied successfully with the help of a previously evaluated numerical model. The parameters explored are the permeability of the sub-slab and the gravel placed beneath it, the amplitude of applied pressure at the installation point of the system and the functioning method: depressurization or pressurization. The mechanisms contributing to the success of the two systems are identified. This numerical study shows that the presence of a layer of gravel beneath the sub-slab considerably improves the performance of the SVS. Considered separately from the extremely permeable sub-slabs, the depressurization systems perform better than the pressurization systems. 17 refs. [Francais] Le fonctionnement des Systemes de Ventilation active du Sol (SVS) a ete etudie a l`aide d`un outil numerique precedemment evalue avec succes. Les parametres explores sont les permeabilites du sol et du gravier place sous plancher bas, l`amplitude de la pression appliquee au point d`installation du systeme, et le mode de fonctionnement: Depressurisation ou Pressurisation. Les mecanismes contribuant au succes des deux systemes sont identifies. Cette etude numerique montre que la presence d`une couche de gravier sous plancher bas ameliore de facon considerable les performances des SVS. Mis a part le cas des sols extremement permeables, les systemes de Depressurisation ont de meilleures performances que les systemes de Pressurisation. 17 refs.

  6. RED SUPERGIANT STARS IN THE LARGE MAGELLANIC CLOUD. I. THE PERIOD-LUMINOSITY RELATION

    SciTech Connect (OSTI)

    Yang Ming; Jiang, B. W. E-mail: bjiang@bnu.edu.cn

    2011-01-20

    From previous samples of red supergiants (RSGs) by various groups, 191 objects are assembled to compose a large sample of RSG candidates in LMC. For 189 of them, the identity as an RSG is verified by their brightness and color indexes in several near- and mid-infrared bands related to the Two Micron All Sky Survey (2MASS) JHK{sub S} bands and the Spitzer/IRAC and Spitzer/MIPS bands. From the visual time-series photometric observations by the ASAS and MACHO projects which cover nearly 8-10 years, the period and amplitude of light variation are analyzed carefully using both the phase dispersion minimization and Period04 methods. According to the properties of light variation, these objects are classified into five categories: (1) 20 objects are saturated in photometry or located in crowded stellar field with poor photometric results, (2) 35 objects with too complex variation to have any certain period, (3) 23 objects with irregular variation, (4) 16 objects with semi-regular variation, and (5) 95 objects with long secondary period (LSP) among which 31 have distinguishable short period and 51 have a long period shorter than 3000 days that can be determined with reasonable accuracy. For the semi-regular variables and the LSP variables with distinguishable short periods, the period-luminosity (P-L) relation is analyzed in the visual, near-infrared, and mid-infrared bands. It is found that the P-L relation is tight in the infrared bands such as the 2MASS JHK{sub S} bands and the Spitzer/IRAC bands, in particular in the Spitzer/IRAC [3.6] and [4.5] bands; meanwhile, the P-L relation is relatively sparse in the V band which may be caused by inhomogeneous interstellar extinction. The results are compared with others' P-L relationships for RSGs and the P-L sequences of red giants in LMC.

  7. Archive

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Magellan: A Cloud Computing Testbed Petascale Initiative Exascale Computing APEX Home R & D Archive Archive Magellan: A Cloud Computing Testbed Cloud computing is gaining a ...

  8. DOSAGE DES ELEMENTS EN TRACE DES CALCAIRES AU SERVICE DE L'ARCHEOLOGIE

    SciTech Connect (OSTI)

    BLANC,A.; HOLMES,L.; HARBOTTLE,G.

    1998-05-01

    Numerous quarries in the Lutetian limestone formations of the Paris Basin provided stone for the building and the decoration of monuments from antiquity to the present. To determine the origin of stone used for masonry and sculptures in these monuments, a team of geologists and archaeologists has investigated 300 quarries and collected 2,300 samples. Petrographic and paleontologic examination of thin sections allows geologists to distinguish Lutetian limestones from Jurassic and Cretaceous limestones. Geologists also seek to formulate hypotheses regarding the origin of Lutetian limestones used for building and sculpture in the Paris region. In the search for the sources of building and sculptural stone, the analytical methods of geologists are limited because often several quarries produce the same lithofacies. A new tool is now available, however, to attack questions of provenance raised by art historians. Because limestones from different sources have distinctive patterns of trace-element concentrations, compositional analysis by neutron activation allows them to compare building or sculptural stone from one monument with stone from quarries or other monuments. This analytical method subjects a powdered limestone sample to standard neutron activation analysis procedures at Brookhaven National Laboratory. With the help of computer programs, the compositional fingerprints of Lutetian limestones can be determined and stored in a database. The limestone database contains data for approximately 2,100 samples from monuments, sculptures and quarries. It is particularly rich in samples from the Paris Basin.

  9. Centrales au gaz et Energies renouvelables: comparer des pommes avec des pommes

    SciTech Connect (OSTI)

    Bolinger, Mark; Wiser, Ryan; Golove, William

    2003-10-20

    The fundamental conclusion that we draw from this analysis is that one should not to base itself blindly on forecasts prices of natural gas when one compare contracts at price fixes with producers of renewable energy with contracts at variable prices with promoters power stations with gas. Indeed, forecasts of the prices of gas do not succeed not to enter the associated costs with the covering of the risk, that they are connected to the negative pressure against the cover, with the CAPM, with costs of transaction or with unspecified combination of three. Thus, insofar as price stability to length term is developed, better way of comparing the two choices would be to have recourse to the data on the prices in the long term natural gas, and not with forecasts of the prices. During three last years at least, the use of these prices in the long term would have besides license to correct a methodological error who, obviously, seem to have supported unduly, and of relatively important way, power stations with natural gas compared to their competitors of renewable energies.

  10. Eight new Milky Way companions discovered in first-year Dark Energy Survey data

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Bechtol, K.

    2015-06-30

    We report the discovery of eight new Milky Way companions inmore » $$\\sim 1800\\;{\\mathrm{deg}}^{2}$$ of optical imaging data collected during the first year of the Dark Energy Survey (DES). Each system is identified as a statistically significant over-density of individual stars consistent with the expected isochrone and luminosity function of an old and metal-poor stellar population. The objects span a wide range of absolute magnitudes (MV from $-2.2$ to $$-7.4\\;\\mathrm{mag}$$), physical sizes ($$10-170\\;\\mathrm{pc}$$), and heliocentric distances ($$30-330\\;\\mathrm{kpc}$$). Based on the low surface brightnesses, large physical sizes, and/or large Galactocentric distances of these objects, several are likely to be new ultra-faint satellite galaxies of the Milky Way and/or Magellanic Clouds. We introduce a likelihood-based algorithm to search for and characterize stellar over-densities, as well as identify stars with high satellite membership probabilities. As a result, we also present completeness estimates for detecting ultra-faint galaxies of varying luminosities, sizes, and heliocentric distances in the first-year DES data.« less

  11. Eight new Milky Way companions discovered in first-year Dark Energy Survey data

    SciTech Connect (OSTI)

    Bechtol, K.; et al.

    2015-06-30

    We report the discovery of eight new Milky Way companions in $\\sim 1800\\;{\\mathrm{deg}}^{2}$ of optical imaging data collected during the first year of the Dark Energy Survey (DES). Each system is identified as a statistically significant over-density of individual stars consistent with the expected isochrone and luminosity function of an old and metal-poor stellar population. The objects span a wide range of absolute magnitudes (MV from $-2.2$ to $-7.4\\;\\mathrm{mag}$), physical sizes ($10-170\\;\\mathrm{pc}$), and heliocentric distances ($30-330\\;\\mathrm{kpc}$). Based on the low surface brightnesses, large physical sizes, and/or large Galactocentric distances of these objects, several are likely to be new ultra-faint satellite galaxies of the Milky Way and/or Magellanic Clouds. We introduce a likelihood-based algorithm to search for and characterize stellar over-densities, as well as identify stars with high satellite membership probabilities. As a result, we also present completeness estimates for detecting ultra-faint galaxies of varying luminosities, sizes, and heliocentric distances in the first-year DES data.

  12. Improving the Field Performance of Natural Gas Furnaces, Chicago, Illinois (Fact Sheet)

    SciTech Connect (OSTI)

    Rothgeb, S.; Brand, L.

    2013-11-01

    The objective of this project is to examine the impact that common installation practices and age-induced equipment degradation may have on the installed performance of natural gas furnaces, as measured by steady-state efficiency and AFUE. PARR identified twelve furnaces of various ages and efficiencies that were operating in residential homes in the Des Moines Iowa metropolitan area and worked with a local HVAC contractor to retrieve them and test them for steady-state efficiency and AFUE in the lab. Prior to removal, system airflow, static pressure, equipment temperature rise, and flue loss measurements were recorded for each furnace. After removal from the field the furnaces were transported to the Gas Technology Institute (GTI) laboratory, where PARR conducted steady-state efficiency and AFUE testing. The test results show that steady-state efficiency in the field was 6.4% lower than that measured for the same furnaces under standard conditions in the lab, which included tuning the furnace input and air flow rate. Comparing AFUE measured under ASHRAE standard conditions with the label value shows no reduction in efficiency for the furnaces in this study over their 15 to 24 years of operation when tuned to standard conditions. Further analysis of the data showed no significant correlation between efficiency change and the age or the rated efficiency of the furnace.

  13. Lessons from Iowa : development of a 270 megawatt compressed air energy storage project in midwest Independent System Operator : a study for the DOE Energy Storage Systems Program.

    SciTech Connect (OSTI)

    Holst, Kent; Huff, Georgianne; Schulte, Robert H.; Critelli, Nicholas

    2012-01-01

    The Iowa Stored Energy Park was an innovative, 270 Megawatt, $400 million compressed air energy storage (CAES) project proposed for in-service near Des Moines, Iowa, in 2015. After eight years in development the project was terminated because of site geological limitations. However, much was learned in the development process regarding what it takes to do a utility-scale, bulk energy storage facility and coordinate it with regional renewable wind energy resources in an Independent System Operator (ISO) marketplace. Lessons include the costs and long-term economics of a CAES facility compared to conventional natural gas-fired generation alternatives; market, legislative, and contract issues related to enabling energy storage in an ISO market; the importance of due diligence in project management; and community relations and marketing for siting of large energy projects. Although many of the lessons relate to CAES applications in particular, most of the lessons learned are independent of site location or geology, or even the particular energy storage technology involved.

  14. Railroad accident report: Head-on collision between Iowa Interstate Railroad Extra 470 West and Extra 406 East with release of hazardous materials near Altoona, Iowa, on July 30, 1988. Irregular report

    SciTech Connect (OSTI)

    Not Available

    1989-07-06

    About 11:40 a.m. central daylight saving time on July 30, 1988, Iowa Interstate Railroad Ltd. (IAIS) freight trains Extra 470 West and Extra 406 East collided head on within the yard limits of Altoona, Iowa, about 10 miles east of Des Moines, Iowa. All 5 locomotive units from both trains; 11 cars of Extra 406 East; and 3 cars, including two tank cars containing denatured alcohol, of Extra 470 West derailed. The denatured alcohol, which was released through the pressure relief valves and the manway domes of the two derailed tank cars, was ignited by the fire resulting from the collision of the locomotives. Both crew members of Extra 470 West were fatally injured; the two crew members of Extra 406 East were only slightly injured. The estimated damage (including lading) as a result of this accident exceeded $1 million. The major safety issues in the accident include operational methods employed by the IAIS, training and selection of train and engine personnel, supervisory oversight by the IAIS, design of closure fittings on hazardous materials rail tanks, and oversight of regional railroads by the Federal Railroad Administration.

  15. Conceptual design of a gas turbine for PFBC applications

    SciTech Connect (OSTI)

    Bannister, R.L.; McGuigan, A.W.; Risley, T.P.; Smith, O.J.

    1992-01-01

    First generation pressurized fluidized bed (PFBC) technology has potential advantages which include: lower capital cost, Unproved environmental performance, shorter lead times, higher efficiency and enhanced fuel flexibility. Coal firing with combustion turbines experiments have been conducted for over forty years. These efforts have evolved to the point where commercial demonstrations are now feasible. The PFBC is one of these technologies. It will be demonstrated as part of the Clean Coal III initiative. PFBC technology is applicable for new installations, replacement of existing equipment as well as repower and retrofit. Included with these options is the opportunity to reduce dependency on fuel oil and well as enhancing environmental performance and increasing efficiency. The turbo-machinery will require design changes to meet the requirements for PFBC application. The major change to the combustion turbine take place in the center section. This section will include provisions to supply compressed air to the PFBC as well as receive vitiated air from the PFBC. These efforts also have the objective of reducing the degree of change from a standard unit. Under a clean coal program a first generation PFBC demonstration win take place at the Des Moines Energy Center. For this demonstration it will be necessary to remove two stages from the 251B12 compressor. This will make the air supplied by the compressor suitable for the PFBC system. The results from this program will be applicable to the DMEC-1 program.

  16. Conceptual design of a gas turbine for PFBC applications

    SciTech Connect (OSTI)

    Bannister, R.L.; McGuigan, A.W.; Risley, T.P.; Smith, O.J.

    1992-12-31

    First generation pressurized fluidized bed (PFBC) technology has potential advantages which include: lower capital cost, Unproved environmental performance, shorter lead times, higher efficiency and enhanced fuel flexibility. Coal firing with combustion turbines experiments have been conducted for over forty years. These efforts have evolved to the point where commercial demonstrations are now feasible. The PFBC is one of these technologies. It will be demonstrated as part of the Clean Coal III initiative. PFBC technology is applicable for new installations, replacement of existing equipment as well as repower and retrofit. Included with these options is the opportunity to reduce dependency on fuel oil and well as enhancing environmental performance and increasing efficiency. The turbo-machinery will require design changes to meet the requirements for PFBC application. The major change to the combustion turbine take place in the center section. This section will include provisions to supply compressed air to the PFBC as well as receive vitiated air from the PFBC. These efforts also have the objective of reducing the degree of change from a standard unit. Under a clean coal program a first generation PFBC demonstration win take place at the Des Moines Energy Center. For this demonstration it will be necessary to remove two stages from the 251B12 compressor. This will make the air supplied by the compressor suitable for the PFBC system. The results from this program will be applicable to the DMEC-1 program.

  17. Improving Gas Furnace Performance: A Field and Laboratory Study at End of Life

    SciTech Connect (OSTI)

    Brand, L.; Yee, S.; Baker, J.

    2015-02-01

    In 2010, natural gas provided 54% of total residential space heating energy the U.S. on a source basis, or 3.5 Quadrillion Btu. Natural gas burned in furnaces accounted for 92% of that total, and boilers and other equipment made up the remainder. A better understanding of installed furnace performance is a key to energy savings for this significant energy usage. In this project, the U.S. Department of Energy Building America team Partnership for Advanced Residential Retrofit examined the impact that common installation practices and age-induced equipment degradation may have on the installed performance of natural gas furnaces over the life of the product, as measured by steady-state efficiency and annual efficiency. The team identified 12 furnaces of various ages and efficiencies that were operating in residential homes in the Des Moines, Iowa, metropolitan area and worked with a local heating, ventilation, and air conditioning contractor to retrieve furnaces and test them at the Gas Technology Institute laboratory for steady-state efficiency and annual efficiency. Prior to removal, system airflow, static pressure, equipment temperature rise, and flue loss measurements were recorded for each furnace as installed in the house.

  18. Technology Solutions Case Study: Improving the Field Performance of Natural Gas Furnaces

    SciTech Connect (OSTI)

    2013-11-01

    The objective of this project is to examine the impact that common installation practices and age-induced equipment degradation may have on the installed performance of natural gas furnaces, as measured by steady-state efficiency and AFUE. PARR identified twelve furnaces of various ages and efficiencies that were operating in residential homes in the Des Moines Iowa metropolitan area and worked with a local HVAC contractor to retrieve them and test them for steady-state efficiency and AFUE in the lab. Prior to removal, system airflow, static pressure, equipment temperature rise, and flue loss measurements were recorded for each furnace. After removal from the field the furnaces were transported to the Gas Technology Institute (GTI) laboratory, where PARR conducted steady-state efficiency and AFUE testing. The test results show that steady-state efficiency in the field was 6.4% lower than that measured for the same furnaces under standard conditions in the lab, which included tuning the furnace input and air flow rate. Comparing AFUE measured under ASHRAE standard conditions with the label value shows no reduction in efficiency for the furnaces in this study over their 15 to 24 years of operation when tuned to standard conditions. Further analysis of the data showed no significant correlation between efficiency change and the age or the rated efficiency of the furnace.

  19. Microsoft Word - FY12 Fee Des.doc

    National Nuclear Security Administration (NNSA)

    NR0000031 copies of the amendment; (b) By acknowledging receipt of this amendment on each copy of the offer submitted; or (c) By separate letter or telegram which includes a reference to the solicitation and amendment numbers. FAILURE OF YOUR ACKNOWLEDGEMENT TO BE RECEIVED AT THE PLACE DESIGNATED FOR THE RECEIPT OF OFFERS PRIOR TO THE HOUR AND DATE SPECIFIED MAY RESULT IN REJECTION OF YOUR OFFER. If by virtue of this amendment you desire to change an offer already submitted, such change may be

  20. Weak lensing by galaxy troughs in DES Science Verification data

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Gruen, D.; Friedrich, O.; Amara, A.; Bacon, D.; Bonnett, C.; Hartley, W.; Jain, B.; M. Jarvis; Kavprzak, T.; Krause, E.; et al

    2015-11-29

    In this study, we measure the weak lensing shear around galaxy troughs, i.e. the radial alignment of background galaxies relative to underdensities in projections of the foreground galaxy field over a wide range of redshift in Science Verification data from the Dark Energy Survey. Our detection of the shear signal is highly significant (10σ–15σ for the smallest angular scales) for troughs with the redshift range z ϵ [0.2, 0.5] of the projected galaxy field and angular diameters of 10 arcmin…1°. These measurements probe the connection between the galaxy, matter density, and convergence fields. By assuming galaxies are biased tracers ofmore » the matter density with Poissonian noise, we find agreement of our measurements with predictions in a fiducial Λ cold dark matter model. The prediction for the lensing signal on large trough scales is virtually independent of the details of the underlying model for the connection of galaxies and matter. Our comparison of the shear around troughs with that around cylinders with large galaxy counts is consistent with a symmetry between galaxy and matter over- and underdensities. In addition, we measure the two-point angular correlation of troughs with galaxies which, in contrast to the lensing signal, is sensitive to galaxy bias on all scales. The lensing signal of troughs and their clustering with galaxies is therefore a promising probe of the statistical properties of matter underdensities and their connection to the galaxy field.« less

  1. Weak lensing by galaxy troughs in DES Science Verification data

    SciTech Connect (OSTI)

    Gruen, D.; Friedrich, O.; Amara, A.; Bacon, D.; Bonnett, C.; Hartley, W.; Jain, B.; M. Jarvis; Kavprzak, T.; Krause, E.; Mana, A.; Rozo, E.; Rykoff, E. S.; Seitz, S.; Sheldon, E.; Troxel, M. A.; Vikram, V.; Abbott, T. M. C.; Abdalla, F. B.; Allam, S.; Armstrong, R.; Banerji, M.; Bauer, A. H.; Becker, M. R.; Benoit-Levy, A.; Bernstein, G. M.; Bernstein, R. A.; Bertin, E.; Bridle, S. L.; Brooks, D.; Buckley-Geer, E.; Burke, D. L.; Capozzi, D.; Rosell, A. Carnero; Carretero, J.; Crocce, M.; Cunha, C. E.; D'Andrea, C. B.; da Costa, L. N.; DePoy, D. L.; Desai, S.; Diehl, H. T.; Dietrich, J. P.; Doel, P.; Eifler, T. F.; Neto, A. Fausti; Fernandez, E.; Flaugher, B.; Fosalba, P.; Frieman, J.; Gerdes, D. W.; Gruendl, R. A.; Gutierrez, G.; Honscheid, K.; James, D. J.; Kuehn, K.; Kuropatkin, N.; Lahav, O.; Li, T. S.; Lima, M.; Maia, M. A. G.; March, M.; Martini, P.; Melchior, P.; Miller, C. J.; Miguel, R.; Mohr, J. J.; Nord, B.; Orgando, R.; Plazas, A. A.; Reil, K.; Romer, A. K.; Roodman, A.; Sako, M.; Sanchez, E.; Scarpine, V.; Schubnell, M.; Sevilla-Noarbe, I.; Smith, R. C.; Soares-Santos, M.; Sobreira, F.; Suchyta, E.; Swanson, M. E. C.; Tarle, G.; Thaler, J.; Thomas, D.; Walker, A. R.; Wechsler, R. H.; Weller, J.; Zhang, Y.; Zuntz, J.

    2015-11-29

    In this study, we measure the weak lensing shear around galaxy troughs, i.e. the radial alignment of background galaxies relative to underdensities in projections of the foreground galaxy field over a wide range of redshift in Science Verification data from the Dark Energy Survey. Our detection of the shear signal is highly significant (10σ–15σ for the smallest angular scales) for troughs with the redshift range z ϵ [0.2, 0.5] of the projected galaxy field and angular diameters of 10 arcmin…1°. These measurements probe the connection between the galaxy, matter density, and convergence fields. By assuming galaxies are biased tracers of the matter density with Poissonian noise, we find agreement of our measurements with predictions in a fiducial Λ cold dark matter model. The prediction for the lensing signal on large trough scales is virtually independent of the details of the underlying model for the connection of galaxies and matter. Our comparison of the shear around troughs with that around cylinders with large galaxy counts is consistent with a symmetry between galaxy and matter over- and underdensities. In addition, we measure the two-point angular correlation of troughs with galaxies which, in contrast to the lensing signal, is sensitive to galaxy bias on all scales. The lensing signal of troughs and their clustering with galaxies is therefore a promising probe of the statistical properties of matter underdensities and their connection to the galaxy field.

  2. Des Plaines Landfill Biomass Facility | Open Energy Information

    Open Energy Info (EERE)

    mW 0.0038 GW Commercial Online Date 2004 Heat Rate (BTUkWh) 12916.67 References EPA Web Site1 Loading map... "minzoom":false,"mappingservice":"googlemaps3","type":"TERRAIN...

  3. Weak Lensing by Galaxy Troughs in DES Science Verification Data

    SciTech Connect (OSTI)

    Gruen, D.

    2015-09-29

    We measure the weak lensing shear around galaxy troughs, i.e. the radial alignment of background galaxies relative to underdensities in projections of the foreground galaxy field over a wide range of redshift in Science Verification data from the Dark Energy Survey. Our detection of the shear signal is highly significant (10σ–15σ for the smallest angular scales) for troughs with the redshift range z ϵ [0.2, 0.5] of the projected galaxy field and angular diameters of 10 arcmin…1°. These measurements probe the connection between the galaxy, matter density, and convergence fields. By assuming galaxies are biased tracers of the matter density with Poissonian noise, we find agreement of our measurements with predictions in a fiducial Λ cold dark matter model. Furthermore, the prediction for the lensing signal on large trough scales is virtually independent of the details of the underlying model for the connection of galaxies and matter. Our comparison of the shear around troughs with that around cylinders with large galaxy counts is consistent with a symmetry between galaxy and matter over- and underdensities. In addition, we measure the two-point angular correlation of troughs with galaxies which, in contrast to the lensing signal, is sensitive to galaxy bias on all scales. Finally, the lensing signal of troughs and their clustering with galaxies is therefore a promising probe of the statistical properties of matter underdensities and their connection to the galaxy field.

  4. Forum des Jeuns du Gabon | Open Energy Information

    Open Energy Info (EERE)

    drought and land degradation, Environmentally sound technologies, Gender, Human rights and Sustainable development plans References "UNEP Major Groups Directory"...

  5. Scientific Cloud Computing Misconceptions

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Scientific Cloud Computing Misconceptions Scientific Cloud Computing Misconceptions July 1, 2011 Part of the Magellan project was to understand both the possibilities and the limitations of cloud computing in the pursuit of science. At a recent conference, Magellan investigator Shane Canon outlined some persistent misconceptions about doing science in the cloud - and what Magellan has taught us about them. » Read the ISGTW story. » Download the slides (PDF, 4.1MB

  6. Browse Societies by Language -- E-print Network Societies by...

    Office of Scientific and Technical Information (OSTI)

    des Sciences, des Lettres et des Arts Tunisian Academy of the Sciences, ... de Psilogie Quebec Society of Psychology -- Socit Qubcoise pour l'tude ...

  7. Galaxy-Galaxy Lensing in the DES Science Verification Data (Journal...

    Office of Scientific and Technical Information (OSTI)

    Covariances from jackknife subsamples of the data are validated with a suite of 50 mock surveys. The results and systematics checks in this work provide a critical input for future ...

  8. Detection of the kinematic Sunyaev-Zel'dovich effect with DES...

    Office of Scientific and Technical Information (OSTI)

    Citation Details In-Document Search Title: Detection of the kinematic Sunyaev-Zel'dovich ... we measure the average central optical depth of the cluster sample, bartaue ...

  9. A Radiometric All-Sky Infrared Camera (RASICAM) for DES/CTIO

    SciTech Connect (OSTI)

    Lewis, Peter M.; Rogers, Howard; Schindler, Rafe H.; /SLAC

    2010-08-25

    A novel radiometric all-sky infrared camera [RASICAM] has been constructed to allow automated real-time quantitative assessment of night sky conditions for the Dark Energy Camera [DECam] located on the Blanco Telescope at the Cerro Tololo Inter-American Observatory in Chile. The camera is optimized to detect the position, motion and optical depth of thin, high (8-10km) cirrus clouds and contrails by measuring their apparent temperature above the night sky background. The camera system utilizes a novel wide-field equiresolution catadioptic mirror system that provides sky coverage of 2{pi} azimuth and 14-90{sup o} from zenith. Several new technological and design innovations allow the RASICAM system to provide unprecedented cloud detection and IR-based photometricity quantification. The design of the RASICAM system is presented.

  10. SEP Success Story: A Touch of Green for Des Moines’ Sherman Hill

    Broader source: Energy.gov [DOE]

    When the Green & Main Initiative completes the renovation of a 1930s grocery store, the previously abandoned building will be LEED Platinum certified, with a green roof and 54 original windows retrofitted to achieve high energy efficiency standards. Learn more.

  11. Microsoft Word - Fermi First Light Review_Final Corrections.doc

    Office of Scientific and Technical Information (OSTI)

    The 3 rd EGRET Catalog (Hartman et al 1999) of 271 sources consists of the single 1991 solar flare bright enough to be detected as a source, the Large Magellanic Cloud (LMC),...

  12. Science Cloud 2011

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Science Cloud 2011 Science Cloud 2011 June 17, 2011 The Magellan teams at NERSC and Argonne recently presented a joint paper detailing their progress and conclusions. At Science Cloud 2011: The Second Workshop on Scientific Cloud Computing, in a paper titled "Magellan: Experiences from a Science Cloud" (PDF, 320KB), lead author Lavanya Ramakrishnan outlined the groups' most recent achievements and conclusions, including a successful run of real-time data analysis for the STAR

  13. Danger radiations

    ScienceCinema (OSTI)

    None

    2011-04-25

    Le conférencier Mons.Hofert parle des dangers et risques des radiations, le contrôle des zones et les précautions à prendre ( p.ex. film badge), comment mesurer les radiations etc.

  14. EIS_Summary

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    ... Des Arc Austin Adona Houston Danville Palestine Perry Corinth Ward Cotton Plant ... Haynes Wheatley Fargo Horseshoe Lake Des Arc Hughes Palestine Ward Cotton Plant Forrest ...

  15. Corrective Action Investigation Plan for Corrective Action Unit 309: Area 12 Muckpiles, Nevada Test Site, Nevada, Rev. No. 0

    SciTech Connect (OSTI)

    Robert F. Boehlecke

    2004-12-01

    This Corrective Action Investigation Plan (CAIP) for Corrective Action Unit (CAU) 309, Area 12 Muckpiles, Nevada Test Site (NTS), Nevada, has been developed in accordance with the ''Federal Facility Agreement and Consent Order'' (FFACO) that was agreed to by the State of Nevada, the U.S. Department of Energy, and the U.S. Department of Defense. The general purpose of the investigation is to ensure that adequate data are collected to provide sufficient and reliable information to identify, evaluate, and select technically viable corrective actions. Corrective Action Unit 309 is comprised of the following three corrective action sites (CASs) in Area 12 of the NTS: (1) CAS 12-06-09, Muckpile; (2) CAS 12-08-02, Contaminated Waste Dump (CWD); and (3) CAS 12-28-01, I-, J-, and K-Tunnel Debris. Corrective Action Site 12-06-09 consists of a muckpile and debris located on the hillside in front of the I-, J-, and K-Tunnels on the eastern slopes of Rainier Mesa in Area 12. The muckpile includes mining debris (muck) and debris generated during the excavation and construction of the I-, J-, and K-Tunnels. Corrective Action Site 12-08-02, CWD, consists of a muckpile and debris and is located on the hillside in front of the re-entry tunnel for K-Tunnel. For the purpose of this investigation CAS 12-28-01 is defined as debris ejected by containment failures during the Des Moines and Platte Tests and the associated contamination that is not covered in the two muckpile CASs. This site consists of debris scattered south of the I-, J-, and K-Tunnel muckpiles and extends down the hillside, across the valley, and onto the adjacent hillside to the south. In addition, the site will cover the potential contamination associated with ''ventings'' along the fault, fractures, and various boreholes on the mesa top and face. One conceptual site model was developed for all three CASs to address possible contamination migration pathways associated with CAU 309. The data quality objective (DQO

  16. ascr_workshop_Jan2011.ppt

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    future computing needs in high-speed turbulent flows Sanjiva Lele and Johan Larsson Stanford University DOE ASCR workshop Jan 5-6, 2011 2 Overview SciDAC: Sanjiva Lele (PI); Moin (Stanford); Cook, Cabot, Sjogreen (LLNL); Zhong (UCLA); Yee (NASA) Other projects: PSAAP, NASA * Objective: Increase fundamental understanding and improve predictive/modeling capability of general compressible turbulence problems, especially shock/turbulence interaction, shock/material-interface interaction. * Present

  17. Energy Citations Database (ECD) - Availability

    Office of Scientific and Technical Information (OSTI)

    vente des publications des Communautes Europeenes 37, rue Glesener-Luxembourg. FD U.S. Fish and Wildlife Service, 18th and C Streets, N.W., Mail Stop 1111, Arlington Square Bldg.,...

  18. Fermilab | Newsroom | Press Releases | March 10, 2015: Scientists...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    3 March 10, 2015 FOR IMMEDIATE RELEASE Scientists find rare dwarf satellite galaxy candidates in Dark Energy Survey data DES-Dwarf-Galaxies DES-Dwarf-Galaxies Previous Next...

  19. Sciences and society

    SciTech Connect (OSTI)

    2008-01-10

    J.Luns des Pays-Bas, ancien sctaire gnral de NATO (OTAN=Organisation du trait de l'Atlantique Nord) parle du pass, prsent et future de la dfense europenne et des relations est et ouest

  20. Celebration of PS

    ScienceCinema (OSTI)

    None

    2011-04-25

    Le DG John Adams parle des premières années du PS avec présentation des dias ainsi il honore Pierre Germain qui après 24 ans de travail quitte sa fonction.

  1. Research- Knowledge

    ScienceCinema (OSTI)

    None

    2011-04-25

    S.Mansholt, connu sur le marché commun de la communité européenne, est agriculteur et agronome de profession et un des pionnier et animateur des affaires d'unification européene

  2. Departure Roger Anthoine

    SciTech Connect (OSTI)

    2007-11-28

    Remerciements et discours du D.G. H.Schopper l'occasion du dpart de Roger Anthoine (attach de presse), qui travaillait dans la communication et quitte le Cern aprs 27 ans de service. Il gardait des relations avec des mdias internationaux et la presse locale; remise des cadeaux: album photo avec images des muss de Genve et un radio aviation; R.A. fait un rsum de ses activits et souvenirs et remercie ses collaborateurs

  3. Gas Technology Institute (Partnership for Advanced Residential...

    Open Energy Info (EERE)

    Technology Institute (Partnership for Advanced Residential Retrofit) Jump to: navigation, search Name: Gas Technology Institute Place: Des Plaines, IL Website:...

  4. Utilization Technology Institute | Open Energy Information

    Open Energy Info (EERE)

    Utilization Technology Institute Jump to: navigation, search Name: Utilization Technology Institute Place: Des Plaines, IL References: Utilization Technology Institute1...

  5. Midday Meeting- Chemically induced Mind Alteration

    ScienceCinema (OSTI)

    None

    2011-04-25

    Le Docteur Hugo Solms parle de l'abus des drogues, pourquoi les gens en prennent et comment vivre sans

  6. PET

    ScienceCinema (OSTI)

    None

    2011-04-25

    le DG fait l'introduction et laisse la parole à plusieurs intervenants au sujet de la physique des particules

  7. Visit CD

    ScienceCinema (OSTI)

    None

    2011-04-25

    Le DG H.Schopper souhaite la bienvenue aux ambassadeurs des pays membres et aux représentants des pays avec lesquels le Cern entretient des relations proches et fait un exposé sur les activités au Cern

  8. PreCam

    SciTech Connect (OSTI)

    Allam, Sahar S.; Tucker, Douglas L.

    2015-01-01

    The Dark Energy Survey (DES) will be taking the next step in probing the properties of Dark Energy and in understanding the physics of cosmic acceleration. A step towards the photometric calibration of DES is to have a quick, bright survey in the DES footprint (PreCam), using a pre-production set of the Dark Energy Camera (DECam) CCDs and a set of 100 mm×100 mm DES filters. The objective of the PreCam Survey is to create a network of calibrated DES grizY standard stars that will be used for DES nightly calibrations and to improve the DES global relative calibrations. Here, we describe the first year of PreCam observation, results, and photometric calibrations.

  9. We

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    tails the requirements of scientific applications that could potentially benefit from cloud computing. We provide an overview of the Magellan testbed in Section 3 and discuss challenges in operating cloud software stacks. In Section 4, we describe the early science adopters of cloud technologies and discuss the impact of these technologies on application design decisions. Section 5 provides answers to a number of key questions related to applicability of cloud computing for scientific workflows.

  10. carverintro.ppt

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Carver David Turner NERSC User Services Group NUG Meeting, October 18, 2010 2 Tutorial Overview * Background * Hardware * Software * Programming * Running Jobs 3 Background * Replace Bassi and Jacquard * Hardware procurement - "Scalable Units" * Two funding sources - Carver * NERSC program funds - Magellan * ARRA funds 4 System Overview * IBM iDataPlex System - 14 compute racks * 80 nodes/rack (1120 total compute nodes) * "Water cooled" - 5 service racks * Login, I/O, and

  11. THEORETICAL CEPHEID PERIOD-LUMINOSITY AND PERIOD-COLOR RELATIONS IN SPITZER IRAC BANDS

    SciTech Connect (OSTI)

    Ngeow, Chow-Choong; Marconi, Marcella; Musella, Ilaria; Cignoni, Michele; Kanbur, Shashsi M.

    2012-02-01

    In this paper, the synthetic period-luminosity (P-L) relations in Spitzer's IRAC bands, based on a series of theoretical pulsation models with varying metal and helium abundance, were investigated. Selected sets of these synthetic P-L relations were compared to the empirical IRAC band P-L relations recently determined from Galactic and Magellanic Clouds Cepheids. For the Galactic case, synthetic P-L relations from model sets with (Y = 0.26, Z = 0.01), (Y = 0.26, Z = 0.02), and (Y = 0.28, Z = 0.02) agree with the empirical Galactic P-L relations derived from the Hubble Space Telescope parallaxes. For Magellanic Cloud Cepheids, the synthetic P-L relations from model sets with (Y = 0.25, Z = 0.008) agree with both of the empirical Large Magellanic Cloud (LMC) and Small Magellanic Cloud P-L relations. Analysis of the synthetic P-L relations from all model sets suggested that the IRAC band P-L relations may not be independent of metallicity, as the P-L slopes and intercepts could be affected by the metallicity and/or helium abundance. We also derive the synthetic period-color (P-C) relations in the IRAC bands. Non-vanishing synthetic P-C relations were found for certain combinations of IRAC band filters and metallicity. However, the synthetic P-C relations disagreed with the [3.6]-[8.0] P-C relation recently found for the Galactic Cepheids. The synthetic [3.6]-[4.5] P-C slope from the (Y = 0.25, Z = 0.008) model set, on the other hand, is in excellent agreement to the empirical LMC P-C counterpart, if a period range 1.0 < log (P) < 1.8 is adopted.

  12. Properties of LMC planetary nebulae and parent populations in the MACHO database

    SciTech Connect (OSTI)

    Alves, D.R. |; Alcock, C.; Cook, K.H.

    1996-10-01

    The MACHO microlensing experiment's time-sampled photometry database contains blue and red lightcurves for nearly 9 million stars in the central bar region of the Large Magellanic Cloud (LMC). We have identified known LMC Planetary Nebulae (PN) in the database and find one, Jacoby 5, to be variable. We additionally present data on the ``parent populations`` of LMC PN, and discuss the star formation history of the LMC bar. 14 refs., 1 fig.

  13. Timeline

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Timeline Timeline Date Event May 1, 2010 Account charging starts Mar 22, 2010 All active NERSC user accounts enabled Mar 17, 2010 Magellan queues added Mar 12, 2010 System accepted Feb 22, 2010 Selected NERSC user accounts enabled Jan 29, 2010 Acceptance Test Begins Jan 04, 2010 System integration begins at NERSC Oakland Scientific Facility Oct 06, 2009 Contract awarded to IBM by DOE Last edited: 2016-04-29 11:34:54

  14. Clouds at CTIO and the Dark Energy Survey

    SciTech Connect (OSTI)

    Neilsen, Jr., Eric

    2015-08-01

    An understanding of the weather patters at Cerro-Tololo Inter-American (CTIO) Observatory, the observing site for the Dark Energy Survey (DES), is important for assessing the efciency of DES operations in using observing time and for planning future operations. CTIO has maintained records of cloud-cover by quarters of nights since 1975. A comparison between these cloud records in the 2013-2014 DES observing season (DES year 1) and achieved observing efciency and exposure quality allows the DES collaboration to make better use of the historical records in survey planning. Plots and tables here relate human recorded cloud-cover to collection of good DES data, show the variation of typical cloud-cover by month, and evaluate the relationship between the El Niño weather pattern and cloud-cover at CTIO.

  15. National Association of the Remodeling Industry (NARI) | Open...

    Open Energy Info (EERE)

    Association of the Remodeling Industry (NARI) Jump to: navigation, search Name: National Association of the Remodeling Industry (NARI) Place: Des Plaines, IL Website: www.nari.org...

  16. Transcendental Meditation

    ScienceCinema (OSTI)

    None

    2011-04-25

    K.Wallace, qui vient des Etats Unis, parle des effects physiologiques de la méditation transcendantale. Il a fait son bachelor en physique à l'Université de Los Angeles et son doctorat en physiologie aussi à Los Angeles, mais à l'Institut de Recherche sur le cerveau. Il travaille maintenat à Harvard Medical School ou il continue des recherches biochimiques et physiologiques sur l'application médicale de la méditation transcendantale. Il s'occupe principalement des maladies cardiaques et de hypertension artérielle.

  17. Worksheet

    U.S. Energy Information Administration (EIA) Indexed Site

    FUEL(DOLLARS)EMPLOYEES","OPERATION(DOLLARS)","MAINTENANCE(DOLLARS)","TOTAL(DOLLARS)","DES... Power Generation (500-507, 510-514) Fuel Cost (501)" 55,"Aberdeen City ...

  18. The english at Cern

    ScienceCinema (OSTI)

    None

    2011-04-25

    Assemblée du personnel anglais traitant des sujets tels affaires sociales, salaires, caisse de pension etc....avec plusieurs conférenciers (date inconnue)

  19. Apollo Solar Energy Inc | Open Energy Information

    Open Energy Info (EERE)

    Inc Jump to: navigation, search Name: Apollo Solar Energy Inc Place: Bethel, Connecticut Zip: 68010 Sector: Solar Product: String representation "The company des ... e &...

  20. "Title","Creator/Author","Publication Date","OSTI Identifier...

    Office of Scientific and Technical Information (OSTI)

    Royale Pour L'Avancement Des Sciences","USDOE","36 MATERIALS SCIENCE Clean Coal Technology Coal - Environmental Processes",,"The feasibility of using carbon dioxide as...

  1. FY 2014 Projects for Improving the Design, Construction, and...

    Energy Savers [EERE]

    Institute (Des Plaines, Ill.) - Simultaneous Waste Heat and Water Recovery from Power Plant Flue Gases for Advanced Energy Systems. The project team will further develop an...

  2. International Association of Public Transport | Open Energy Informatio...

    Open Energy Info (EERE)

    search Name: International Association of Public Transport Address: Rue Sainte-Marie 6 (Quai des Charbonnages) Place: Brussels, Belgium Zip: B-1080 Sector: Vehicles Year...

  3. Photometric Redshifts for the Dark Energy Survey and VISTA and...

    Office of Scientific and Technical Information (OSTI)

    We conduct a detailed analysis of the photometric redshift requirements for the proposed Dark Energy Survey (DES) using two sets of mock galaxy simulations and an artificial neural ...

  4. Search for: All records | SciTech Connect

    Office of Scientific and Technical Information (OSTI)

    ... analysis of the photometric redshift requirements for the proposed Dark Energy Survey (DES) using two sets of mock galaxy simulations and an artificial neural network code-ANNz. ...

  5. Search for: All records | SciTech Connect

    Office of Scientific and Technical Information (OSTI)

    ... of photometric redshifts is to utilize cross-correlation statistics in some form. ... the best possible calibration from cross-correlation methods for DES and LSST. We thus ...

  6. Search for: All records | DOE PAGES

    Office of Scientific and Technical Information (OSTI)

    ... of photometric redshifts is to utilize cross-correlation statistics in some form. ... the best possible calibration from cross-correlation methods for DES and LSST. We thus ...

  7. Spectroscopic Needs for Imaging Dark Energy Experiments (Journal...

    Office of Scientific and Technical Information (OSTI)

    ... of photometric redshifts is to utilize cross-correlation statistics in some form. ... the best possible calibration from cross-correlation methods for DES and LSST. We thus ...

  8. Departure Roger Anthoine

    ScienceCinema (OSTI)

    None

    2011-04-25

    Remerciements et discours du D.G. H.Schopper à l'occasion du départ de Roger Anthoine (attaché de presse), qui travaillait dans la communication et quitte le Cern après 27 ans de service. Il gardait des relations avec des médias internationaux et la presse locale; remise des cadeaux: album photo avec images des musés de Genève et un radio aviation; R.A. fait un résumé de ses activités et souvenirs et remercie ses collaborateurs

  9. 65th Birthday of Dr.Owen Lock

    ScienceCinema (OSTI)

    None

    2011-04-25

    Remerciements au Dr.Owen Lock, un des pionniers du Cern, à l'occasion de son 65me anniversaire et sa retraite (avec plusieurs intervenants)

  10. Browse by Discipline -- E-print Network Subject Pathways: Plasma...

    Office of Scientific and Technical Information (OSTI)

    Ecole des Mines de Nantes Kasher, Roni (Roni Kasher) - Zuckerberg Institute for Water Research, Zuckerberg Institute for Water Research, Jacob Blaustein Institutes for Desert ...

  11. Jawaharlal Nehru

    ScienceCinema (OSTI)

    None

    2011-04-25

    L'orateur S.E. Giusti del Giardino a connu Nehru (ennemi des castes) les dernières années de sa vie

  12. Application for presidential permit OE Docket No. PP-371 Northern...

    Office of Environmental Management (EM)

    ("HVDC") transmission line (the "Application") from the Des Cantons substation in Quebec, to Franklin, New Hampshire (the "Project"). Northern Pass Transmission, LLC Docket No. ...

  13. St. Charles County, Missouri: Energy Resources | Open Energy...

    Open Energy Info (EERE)

    Missouri O'Fallon, Missouri Portage Des Sioux, Missouri St. Charles, Missouri St. Paul, Missouri St. Peters, Missouri Weldon Spring Heights, Missouri Weldon Spring, Missouri...

  14. General Staff Meeting

    ScienceCinema (OSTI)

    None

    2011-04-25

    Le DG H.Schopper informe le personnel des derniers événements au Cern, comme: 1.) Décision du LEP 2.) Budget 3.) Pension

  15. Solaire Durance | Open Energy Information

    Open Energy Info (EERE)

    Jump to: navigation, search Name: Solaire Durance Place: France Sector: Solar Product: Joint venture between French state bank la Caisse des Dpots and French solar power...

  16. Energy Savings with Acceptable Indoor Air Quality Through Improved Air Flow Control in Residential Retrofit

    Office of Energy Efficiency and Renewable Energy (EERE)

    Lead Performer: Gas Technology Institute—Des Plaines, IL Partners: -- University of Illinois, Urbana IL -- Midwest Energy Efficiency Alliance, Chicago IL

  17. Low-Cost Gas Heat Pump For Building Space Heating | Department...

    Broader source: Energy.gov (indexed) [DOE]

    Credit: Stone Mountain Technologies Lead Performer: Stone Mountain Technologies - Erwin, TN Partners: -- A.O. Smith - Milwaukee, WI -- Gas Technology Institute - Des Plaines, IL ...

  18. The endocrine disruptor diethylstilbestrol induces adipocyte differentiation and promotes obesity in mice

    SciTech Connect (OSTI)

    Hao, Chan-Juan; Cheng, Xue-Jia; Xia, Hong-Fei Ma, Xu

    2012-08-15

    Epidemiology studies indicate that exposure to endocrine disruptors during developmental “window” contributes to adipogenesis and the development of obesity. Implication of endocrine disruptor such as diethylstilbestrol (DES) on adipose tissue development has been poorly investigated. Here we evaluated the effects of DES on adipocyte differentiation in vitro and in vivo, and explored potential mechanism involved in its action. DES induced 3T3-L1 preadipocyte differentiation in a dose-dependent manner, and activated the expression of estrogen receptor (ER) and peroxisome proliferator-acivated receptor (PPAR) γ as well as its target genes required for adipogenesis in vitro. ER mediated the enhancement of DES-induced PPARγ activity. Moreover, DES perturbed key regulators of adipogenesis and lipogenic pathway in vivo. In utero exposure to low dose of DES significantly increased body weight, liver weight and fat mass in female offspring at postnatal day (PND) 60. In addition, serum triglyceride and glucose levels were also significantly elevated. These results suggest that perinatal exposure to DES may be expected to increase the incidence of obesity in a sex-dependent manner and can act as a potential chemical stressor for obesity and obesity-related disorders. -- Highlights: ► DES induced adipocyte differentiation in a dose-dependent manner in 3T3-L1 cells. ► DES activated adipogenic critical regulators and markers in vitro and in vivo. ► Perinatal exposure to DES led to the obese phenotype in female offspring. ► DES might be a potential chemical stressor for obesity and obesity-related disorders.

  19. Memorial Lew Kowarski

    ScienceCinema (OSTI)

    None

    2011-04-25

    Le DG J.Adams et d'autres intervenants rendent hommage à L.Kowarski (1907-1979), un des pionniers du Cern en 1952, né à St.Petersbourg et physicien, chimiste et ingénieur. Depuis sa retraite en 1972, il se consacra à l'enseignement et est conseiller des Nations Unies.

  20. Science and Society

    ScienceCinema (OSTI)

    None

    2011-04-25

    Le conférencier (qui? L'introduction manque) est économiste et directeur d'un institut de recherche. Il parlera des conséquences économiques désastreuses des dépenses militaires.

  1. Sciences and society

    ScienceCinema (OSTI)

    None

    2011-04-25

    J.Luns des Pays-Bas, ancien sécétaire général de NATO (OTAN=Organisation du traité de l'Atlantique Nord) parle du passé, présent et future de la défense européenne et des relations est et ouest

  2. CX-001027: Categorical Exclusion Determination

    Broader source: Energy.gov [DOE]

    Development of an Autogas Network (Des Plains)CX(s) Applied: A9, B2.5, B3.6, B5.1Date: 03/02/2010Location(s): Des Plaines, IllinoisOffice(s): Energy Efficiency and Renewable Energy, National Energy Technology Laboratory

  3. CX-005264: Categorical Exclusion Determination

    Broader source: Energy.gov [DOE]

    Illinois-City-Des PlainesCX(s) Applied: A9, B2.5, B3.6, B5.1Date: 02/15/2011Location(s): Des Plaines, IllinoisOffice(s): Energy Efficiency and Renewable Energy

  4. The new role of scientists

    ScienceCinema (OSTI)

    None

    2011-04-25

    Le D.G. Jentschke fait l'introduction et présente le Prof.Kowarsky, spécialiste en microbiologie, physique nucléaire et une des fondateurs du Cern. Il parle entre autre de l'énergie nucléaire (pacifique)et de remise en questions des valeurs scientifiques et techniques

  5. Meeting Jentschke

    ScienceCinema (OSTI)

    None

    2011-04-25

    Après une introduction des dernières recherches et nouvelles au Cern, le DG W.Jentschke parle du futur management du Cern avec deux nouv directeurs générales, responsables pour les 5 ans prochains: le Dr.J.B.Adams qui s'occupera de l'administration du Cern et aussi de la construction des bâtiments et équipements et Le Dr.L.van Hove qui sera responsable pour les activités de la recherche. Le DG parle des changes et structures prévus, des services communs, des différentes divisions et leurs chefs etc...

  6. Stellar kinematics and metallicities in the ultra-faint dwarf galaxy Reticulum II

    SciTech Connect (OSTI)

    Simon, J. D.

    2015-07-23

    With this study, we present Magellan/M2FS, Very Large Telescope/GIRAFFE, and Gemini South/GMOS spectroscopy of the newly discovered Milky Way satellite Reticulum II. Based on the spectra of 25 Ret II member stars selected from Dark Energy Survey imaging, we measure a mean heliocentric velocity of $62.8\\pm 0.5\\;\\mathrm{km}\\;{{\\rm{s}}}^{-1}$ and a velocity dispersion of $3.3\\pm 0.7\\;\\mathrm{km}\\;{{\\rm{s}}}^{-1}$. The mass-to-light ratio of Ret II within its half-light radius is $470\\pm 210\\ {M}_{\\odot }/{L}_{\\odot }$, demonstrating that it is a strongly dark matter-dominated system. Despite its spatial proximity to the Magellanic Clouds, the radial velocity of Ret II differs from that of the LMC and SMC by 199 and 83 $\\mathrm{km}\\ {{\\rm{s}}}^{-1}$, respectively, suggesting that it is not gravitationally bound to the Magellanic system. The likely member stars of Ret II span 1.3 dex in metallicity, with a dispersion of 0.28 ± 0.09 dex, and we identify several extremely metal-poor stars with ${\\rm{[Fe/H]}}\\lt -3$. In combination with its luminosity, size, and ellipticity, these results confirm that Ret II is an ultra-faint dwarf galaxy. With a mean metallicity of ${\\rm{[Fe/H]}}=-2.65\\pm 0.07$, Ret II matches Segue 1 as the most metal-poor galaxy known. Although Ret II is the third-closest dwarf galaxy to the Milky Way, the line-of-sight integral of the dark matter density squared is ${\\mathrm{log}}_{10}(J)=18.8\\pm 0.6\\;\\;\\mathrm{GeV}{\\;}^{2}\\;{\\mathrm{cm}}^{-5}\\;$ within 0fdg2, indicating that the predicted gamma-ray flux from dark matter annihilation in Ret II is lower than that of several other dwarf galaxies.

  7. Stellar kinematics and metallicities in the ultra-faint dwarf galaxy Reticulum II

    SciTech Connect (OSTI)

    Simon, J. D.

    2015-07-23

    With this study, we present Magellan/M2FS, Very Large Telescope/GIRAFFE, and Gemini South/GMOS spectroscopy of the newly discovered Milky Way satellite Reticulum II. Based on the spectra of 25 Ret II member stars selected from Dark Energy Survey imaging, we measure a mean heliocentric velocity of $62.8\\pm 0.5\\;\\mathrm{km}\\;{{\\rm{s}}}^{-1}$ and a velocity dispersion of $3.3\\pm 0.7\\;\\mathrm{km}\\;{{\\rm{s}}}^{-1}$. The mass-to-light ratio of Ret II within its half-light radius is $470\\pm 210\\ {M}_{\\odot }/{L}_{\\odot }$, demonstrating that it is a strongly dark matter-dominated system. Despite its spatial proximity to the Magellanic Clouds, the radial velocity of Ret II differs from that of the LMC and SMC by 199 and 83 $\\mathrm{km}\\ {{\\rm{s}}}^{-1}$, respectively, suggesting that it is not gravitationally bound to the Magellanic system. The likely member stars of Ret II span 1.3 dex in metallicity, with a dispersion of 0.28 0.09 dex, and we identify several extremely metal-poor stars with ${\\rm{[Fe/H]}}\\lt -3$. In combination with its luminosity, size, and ellipticity, these results confirm that Ret II is an ultra-faint dwarf galaxy. With a mean metallicity of ${\\rm{[Fe/H]}}=-2.65\\pm 0.07$, Ret II matches Segue 1 as the most metal-poor galaxy known. Although Ret II is the third-closest dwarf galaxy to the Milky Way, the line-of-sight integral of the dark matter density squared is ${\\mathrm{log}}_{10}(J)=18.8\\pm 0.6\\;\\;\\mathrm{GeV}{\\;}^{2}\\;{\\mathrm{cm}}^{-5}\\;$ within 0fdg2, indicating that the predicted gamma-ray flux from dark matter annihilation in Ret II is lower than that of several other dwarf galaxies.

  8. Featured Announcements

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    June 2011 New 1 Terabyte Memory Node June 17, 2011 by Francesca Verdier A new "extra large" memory node that has four 8-core Nehalem EX processors (32 cores total) and 1TB memory has been deployed in the Carver/Magellan complex. See Memory Considerations on Carver. Read the full post SC11 Education Program Applications due July 31 June 9, 2011 by Francesca Verdier Applications for the Education Program are now being accepted. Submission website: https://submissions.supercomputing.org

  9. Pulsation modes of long-period variables in the period-luminosity plane

    SciTech Connect (OSTI)

    Soszyński, I.; Udalski, A.; Wood, P. R. E-mail: udalski@astrouw.edu.pl

    2013-12-20

    We present a phenomenological analysis of long-period variables (LPVs) in the Large Magellanic Cloud with the aim of detecting pulsation modes associated with different period-luminosity (PL) relations. Among brighter LPVs, we discover a group of triple-mode semi-regular variables with the fundamental, first-overtone, and second-overtone modes simultaneously excited, which fall on PL sequences C, C', and B, respectively. The mode identification in the fainter red giants is more complicated. We demonstrate that the fundamental-mode pulsators partly overlap with the first-overtone modes. We show a possible range of fundamental mode and first overtone periods in the PL diagram.

  10. New 1 Terabyte Memory Node

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    New 1 Terabyte Memory Node New 1 Terabyte Memory Node June 17, 2011 by Francesca Verdier A new "extra large" memory node that has four 8-core Nehalem EX processors (32 cores total) and 1TB memory has been deployed in the Carver/Magellan complex. See Memory Considerations on Carver. Subscribe via RSS Subscribe Browse by Date August 2016 June 2016 May 2016 April 2016 January 2016 December 2015 November 2015 October 2015 September 2015 August 2015 July 2015 April 2015 March 2015 January

  11. The Next Generation Microlensing Search: SuperMacho

    SciTech Connect (OSTI)

    Drake, A; Cook, K; Hiriart, R; Keller, S; Miknaitis, G; Nilolaev, S; Olsen, K; Prochter, G; Rest, A; Schmidt, B; Smith, C; Stubbs, C; Suntzeff, N; Welch, D; Becker, A; Clocchiati, A; Covarrubias, R

    2003-10-27

    Past microlensing experiments such as the MACHO project have discovered the presence of a larger than expected number of microlensing events toward the Large Magellanic Cloud (LMC). These events could represent a large fraction of the dark matter in the halo of our Galaxy, if they are indeed due to halo lenses. However the locations of most of the lenses are poorly defined. The SuperMacho project will detect and follow up {approx}60 microlensing events exhibiting special properties due to binarity, etc., will allow us to better determine the location and nature of the lenses causing the LMC microlensing events.

  12. The Dark Energy Survey: More than dark energy - An overview

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Abbott, T.

    2016-03-21

    This overview article describes the legacy prospect and discovery potential of the Dark Energy Survey (DES) beyond cosmological studies, illustrating it with examples from the DES early data. DES is using a wide-field camera (DECam) on the 4m Blanco Telescope in Chile to image 5000 sq deg of the sky in five filters (grizY). By its completion the survey is expected to have generated a catalogue of 300 million galaxies with photometric redshifts and 100 million stars. In addition, a time-domain survey search over 27 sq deg is expected to yield a sample of thousands of Type Ia supernovae andmore » other transients. The main goals of DES are to characterise dark energy and dark matter, and to test alternative models of gravity; these goals will be pursued by studying large scale structure, cluster counts, weak gravitational lensing and Type Ia supernovae. However, DES also provides a rich data set which allows us to study many other aspects of astrophysics. In this paper we focus on additional science with DES, emphasizing areas where the survey makes a difference with respect to other current surveys. The paper illustrates, using early data (from `Science Verification', and from the first, second and third seasons of observations), what DES can tell us about the solar system, the Milky Way, galaxy evolution, quasars, and other topics. In addition, we show that if the cosmological model is assumed to be Lambda+ Cold Dark Matter (LCDM) then important astrophysics can be deduced from the primary DES probes. Lastly, highlights from DES early data include the discovery of 34 Trans Neptunian Objects, 17 dwarf satellites of the Milky Way, one published z > 6 quasar (and more confirmed) and two published superluminous supernovae (and more confirmed).« less

  13. Mass map shines light on dark matter | Argonne National Laboratory

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Mass map shines light on dark matter By Sarah Schlieder * July 9, 2015 Tweet EmailPrint Dark matter may find it tougher to hide in our universe. An international team of researchers has developed a new map of the distribution of dark matter in the universe using data from the Dark Energy Survey (DES). The DES, underway at the Blanco telescope in Chile, is a cosmological galaxy survey that will map approximately an eighth of the visible sky. The primary aim of the DES is to better characterize

  14. Two-dimensional electron gas in monolayer InN quantum wells

    SciTech Connect (OSTI)

    Pan, Wei; Dimakis, Emmanouil; Wang, George T.; Moustakas, Theodore D.; Tsui, Daniel C.

    2014-11-24

    We report in this letter experimental results that confirm the two-dimensional nature of the electron systems in monolayer InN quantum wells embedded in GaN barriers. The electron density and mobility of the two-dimensional electron system (2DES) in these InN quantum wells are 5×1015 cm-2 and 420 cm2 /Vs, respectively. Moreover, the diagonal resistance of the 2DES shows virtually no temperature dependence in a wide temperature range, indicating the topological nature of the 2DES.

  15. Two-dimensional electron gas in monolayer InN quantum wells

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Pan, Wei; Dimakis, Emmanouil; Wang, George T.; Moustakas, Theodore D.; Tsui, Daniel C.

    2014-11-24

    We report in this letter experimental results that confirm the two-dimensional nature of the electron systems in monolayer InN quantum wells embedded in GaN barriers. The electron density and mobility of the two-dimensional electron system (2DES) in these InN quantum wells are 5×1015 cm-2 and 420 cm2 /Vs, respectively. Moreover, the diagonal resistance of the 2DES shows virtually no temperature dependence in a wide temperature range, indicating the topological nature of the 2DES.

  16. DETAILED COMPOSITIONAL ANALYSIS OF THE HEAVILY POLLUTED DBZ WHITE DWARF SDSS J073842.56+183509.06: A WINDOW ON PLANET FORMATION?

    SciTech Connect (OSTI)

    Dufour, P.; Fontaine, G.; Bergeron, P.; Kilic, M.; Melis, C.; Bochanski, J.

    2012-04-10

    We present a new model atmosphere analysis of the most metal-contaminated white dwarf known, the DBZ SDSS J073842.56+183509.06. Using new high-resolution spectroscopic observations taken with Keck and Magellan, we determine precise atmospheric parameters and measure abundances of 14 elements heavier than helium. We also report new Spitzer mid-infrared photometric data that are used to better constrain the properties of the debris disk orbiting this star. Our detailed analysis, which combines data taken from seven different observational facilities (Galaxy Evolution Explorer, Gemini, Keck, Magellan, MMT, Sloan Digital Sky Survey, and Spitzer), clearly demonstrates that J0738+1835 is accreting large amounts of rocky terrestrial-like material that has been tidally disrupted into a debris disk. We estimate that the body responsible for the photospheric metal contamination was at least as large as Ceres, but was much drier, with less than 1% of the mass contained in the form of water ice, indicating that it formed interior to the snow line around its parent star. We also find a correlation between the abundances (relative to Mg and bulk Earth) and the condensation temperature; refractory species are clearly depleted, while the more volatile elements are possibly enhanced. This could be the signature of a body that formed in a lower temperature environment than where Earth formed. Alternatively, we could be witnessing the remains of a differentiated body that lost a large part of its outer layers.

  17. The mass of the black hole in LMC X-3

    SciTech Connect (OSTI)

    Orosz, Jerome A.; Steiner, James F.; McClintock, Jeffrey E.; Buxton, Michelle M.; Bailyn, Charles D.; Steeghs, Danny; Guberman, Alec; Torres, Manuel A. P. E-mail: jsteiner@cfa.harvard.edu E-mail: michelle.buxton@yale.edu E-mail: D.T.H.Steeghs@warwick.ac.uk E-mail: M.Torres@sron.nl

    2014-10-20

    We analyze a large set of new and archival photometric and spectroscopic observations of LMC X-3 to arrive at a self-consistent dynamical model for the system. Using echelle spectra obtained with the Magellan Inamori Kyocera Echelle instrument on the 6.5 m Magellan Clay telescope and the UVES instrument on the second 8.2 m Very Large Telescope, we find a velocity semiamplitude for the secondary star of K {sub 2} = 241.1 6.2 km s{sup 1}, where the uncertainty includes an estimate of the systematic error caused by X-ray heating. Using the spectra, we also find a projected rotational velocity of V {sub rot}sin i = 118.5 6.6 km s{sup 1}. From an analysis of archival B and V light curves as well as new B and V light curves from the SMARTS 1.3 m telescope, we find an inclination of i = 69.84 0.37 for models that do not include X-ray heating and an inclination of i = 69.24 0.72 for models that incorporate X-ray heating. Adopting the latter inclination measurement, we find masses of 3.63 0.57 M {sub ?} and 6.98 0.56 M {sub ?} for the companion star and the black hole, respectively. We briefly compare our results with earlier work and discuss some of their implications.

  18. Identifying high-redshift gamma-ray bursts with RATIR

    SciTech Connect (OSTI)

    Littlejohns, O. M.; Butler, N. R. [School of Earth and Space Exploration, Arizona State University, AZ 85287 (United States); Cucchiara, A. [Goddard Space Flight Center, Greenbelt, MD 20771 (United States); Watson, A. M.; Lee, W. H.; Richer, M. G.; De Diego, J. A.; Georgiev, L.; Gonzlez, J.; Romn-Ziga, C. G. [Instituto de Astronoma, Universidad Nacional Autnoma de Mxico, Apartado Postal 70-264, 04510 Mxico, D. F. (Mexico); Kutyrev, A. S.; Troja, E.; Gehrels, N.; Moseley, H. [NASA, Goddard Space Flight Center, Greenbelt, MD 20771 (United States); Klein, C. R.; Fox, O. D.; Bloom, J. S. [Astronomy Department, University of California, Berkeley, CA 94720-7450 (United States); Prochaska, J. X.; Ramirez-Ruiz, E. [Department of Astronomy and Astrophysics, UCO/Lick Observatory, University of California, 1156 High Street, Santa Cruz, CA 95064 (United States)

    2014-07-01

    We present a template-fitting algorithm for determining photometric redshifts, z {sub phot}, of candidate high-redshift gamma-ray bursts (GRBs). Using afterglow photometry, obtained by the Reionization and Transients InfraRed (RATIR) camera, this algorithm accounts for the intrinsic GRB afterglow spectral energy distribution, host dust extinction, and the effect of neutral hydrogen (local and cosmological) along the line of sight. We present the results obtained by this algorithm and the RATIR photometry of GRB 130606A, finding a range of best-fit solutions, 5.6 < z {sub phot} < 6.0, for models of several host dust extinction laws (none, the Milky Way, Large Magellanic Clouds, and Small Magellanic Clouds), consistent with spectroscopic measurements of the redshift of this GRB. Using simulated RATIR photometry, we find that our algorithm provides precise measures of z {sub phot} in the ranges of 4 < z {sub phot} ? 8 and 9 < z {sub phot} < 10 and can robustly determine when z {sub phot} > 4. Further testing highlights the required caution in cases of highly dust-extincted host galaxies. These tests also show that our algorithm does not erroneously find z {sub phot} < 4 when z {sub sim} > 4, thereby minimizing false negatives and allowing us to rapidly identify all potential high-redshift events.

  19. I/O Performance of Virtualized Cloud Environments

    SciTech Connect (OSTI)

    Ghoshal, Devarshi; Canon, Shane; Ramakrishnan, Lavanya

    2011-11-03

    The scientific community is exploring the suitability of cloud infrastructure to handle High Performance Computing (HPC) applications. The goal of Magellan, a project funded through DOE ASCR, is to investigate the potential role of cloud computing to address the computing needs of the Department of Energy?s Office of Science, especially for mid-range computing and data-intensive applications which are not served through existing DOE centers today. Prior work has shown that applications with significant communication orI/O tend to perform poorly in virtualized cloud environments. However, there is a limited understanding of the I/O characteristics in virtualized cloud environments. This paper will present our results in benchmarking the I/O performance over different cloud and HPC platforms to identify the major bottlenecks in existing infrastructure. We compare the I/O performance using IOR benchmark on two cloud platforms - Amazon and Magellan. We analyze the performance of different storage options available, different instance types in multiple availability zones. Finally, we perform large-scale tests in order to analyze the variability in the I/O patterns over time and region. Our results highlight the overhead and variability in I/O performance on both public and private cloud solutions. Our results will help applications decide between the different storage options enabling applications to make effective choices.

  20. FIRST EVIDENCE OF GLOBULAR CLUSTER FORMATION FROM THE EJECTA OF PROMPT TYPE Ia SUPERNOVAE

    SciTech Connect (OSTI)

    Tsujimoto, Takuji [National Astronomical Observatory of Japan, Mitaka-shi, Tokyo 181-8588 (Japan); Bekki, Kenji, E-mail: taku.tsujimoto@nao.ac.jp [ICRAR, M468, The University of Western Australia, 35 Stirling Highway, Crawley, WA 6009 (Australia)

    2012-06-01

    Recent spectroscopic observations of globular clusters (GCs) in the Large Magellanic Cloud (LMC) have discovered that one of the intermediate-age GCs, NGC 1718, with [Fe/H] = -0.7 has an extremely low [Mg/Fe] ratio of {approx}-0.9. We propose that NGC 1718 was formed from the ejecta of Type Ia supernovae mixed with very metal-poor ([Fe/H] <-1.3) gas about {approx}2 Gyr ago. The proposed scenario is shown to be consistent with the observed abundances of Fe-group elements such as Cr, Mn, and Ni. In addition, compelling evidence for asymptotic giant branch stars playing a role in chemical enrichment during this GC formation is found. We suggest that the origin of the metal-poor gas is closely associated with efficient gas transfer from the outer gas disk of the Small Magellanic Cloud to the LMC disk. We anticipate that the outer part of the LMC disk contains field stars exhibiting significantly low [Mg/Fe] ratios, formed through the same process as NGC 1718.

  1. Renewable Energy Research | Open Energy Information

    Open Energy Info (EERE)

    Research Jump to: navigation, search Name: Renewable Energy Research Address: 2113 C Boulevard St Regis Place: Dollard des Ormeaux Zip: H9B 2M9 Region: Canada Sector: Marine and...

  2. Churches and Apartheid

    ScienceCinema (OSTI)

    None

    2011-04-25

    Lucas Vischer fait parti du concile mondial des églises et nous parle d'eglises et d'apartheid en Afrique du Sud et se pose la question d'un changement sans violence.....

  3. CX-003877: Categorical Exclusion Determination

    Office of Energy Efficiency and Renewable Energy (EERE)

    Hybrid Membrane/Absorption Process for Post-Combustion Carbon Dioxide CaptureCX(s) Applied: B3.6Date: 09/10/2010Location(s): Des Plaines, IllinoisOffice(s): Fossil Energy, National Energy Technology Laboratory

  4. DG's Meeting

    ScienceCinema (OSTI)

    None

    2011-04-25

    Exposés du DG H.Schopper, Blackburne et du président du comité des finances concernant le budget, salaires, pensions etc...avec discussion et questions

  5. Science and Society-Consequences of engineering

    ScienceCinema (OSTI)

    None

    2011-04-25

    Le conférencier Mons.Rorsch parle des possibles conséquences économiques et culturelles de la technologie en générale, aussi pour l'environnement

  6. Eyes Witness Report on South Vietnam

    ScienceCinema (OSTI)

    None

    2011-04-25

    Mons. Nielson, conseiller des Etats Unis auprès de L'ONU, apporte son témoignage et exprime son opinion quand à la guerre du Vietnam (Sud)

  7. Expo NL inauguration

    ScienceCinema (OSTI)

    None

    2011-04-25

    Le DG H.Schopper souhaite la bienvenue à toutes les personnes présentes. Plusieurs discours à l'occasion de l'inauguration officielle de l'expo des Pays-Bas.

  8. Fermilab Today

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Russia. Read more Frontier Science Result: DES The Dark Energy Survey looks at massive galaxy clusters - and finds filaments With data from the new DECam imager, the Dark Energy...

  9. Cosmology constraints from shear peak statistics in Dark Energy...

    Office of Scientific and Technical Information (OSTI)

    varying Omegarm m and sigma8, fixing w -1, Omegarm b 0.04, h 0.7 and ns1, to which we have applied the DES SV mask and redshift distribution. ...

  10. CX-004386: Categorical Exclusion Determination

    Office of Energy Efficiency and Renewable Energy (EERE)

    Chicago Area Alternative Fuels Deployment ProjectCX(s) Applied: B5.1Date: 11/04/2010Location(s): Des Plaines, IllinoisOffice(s): Energy Efficiency and Renewable Energy, National Energy Technology Laboratory

  11. Fragment Screen against HIV Protease: Discovery of Two Allosteric...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Screen against HIV Protease. Chem. Biol. Drug Des. 75: 257-268. References Brenner, B., Routy, J-P., Quan, Y., Moisi, D., Oliveira, M., Turner, D., Wainberg, M. A. &...

  12. Workplace Charging Challenge Partner: Schneider Electric

    Broader source: Energy.gov [DOE]

    Joined the Challenge: March 2013Headquarters: Palatine, ILCharging Locations: Cedar Rapids, IA; Palatine, IL; O'Fallon, MO; Des Plaines, IL; Knightdale, NC; West Kingston, RI; North Andover, MA;...

  13. Churches and Apartheid

    SciTech Connect (OSTI)

    2006-01-16

    Lucas Vischer fait parti du concile mondial des glises et nous parle d'eglises et d'apartheid en Afrique du Sud et se pose la question d'un changement sans violence.....

  14. Photometric Redshifts for the Dark Energy Survey and VISTA and...

    Office of Scientific and Technical Information (OSTI)

    the photometric redshift estimate by a factor of two at z > 1. We draw attention to the ... By removing all galaxies with a 1sigma photo-z scatter greater than 0.1 from our DES+VHS ...

  15. Multinational societies and syndicates

    ScienceCinema (OSTI)

    None

    2011-04-25

    Monsieur Charles Levinson, par la longue expérience qu'il a acquise au contact des sociétés multinationales et syndicats, nous en parle ce soir

  16. CX-000339: Categorical Exclusion Determination

    Broader source: Energy.gov [DOE]

    Chicago Area Alternative Fuel Deployment ProjectCX(s) Applied: A1, A9Date: 12/10/2009Location(s): Des Plaines, IllinoisOffice(s): Energy Efficiency and Renewable Energy, National Energy Technology Laboratory

  17. Meditation and Reality

    ScienceCinema (OSTI)

    None

    2011-04-25

    A.Sujata demande dans son exposé entre autre à ceux/celles des auditeurs/trices qui sont heureux/ses, de lever la main.....qu'est le bonheur?

  18. Senior Staff Meeting

    ScienceCinema (OSTI)

    None

    2011-04-25

    Le DG C.Rubbia informe sur les négociations avec le personnel, les discussions avec le conseil d'administration et le budget, suivi des questions

  19. Colloquy Niels Bohr

    ScienceCinema (OSTI)

    None

    2011-04-25

    Célébration du 100me anniversaire de Niels Bohr (1885 - 1962), un des fondateurs de la physique moderne. Plusieurs orateurs parlent de cet homme et le développement de la physique

  20. HyRadix Inc | Open Energy Information

    Open Energy Info (EERE)

    search Name: HyRadix Inc Place: Des Plaines,, Illinois Zip: IL 60018-1 Sector: Hydro, Hydrogen Product: The company aims to develop and supply small-scale hydrogen generation...

  1. TO: Honorable Patricia Hoffman, Assistant Secretary for Electricity...

    Broader source: Energy.gov (indexed) [DOE]

    March 18, 2016 RE: National Distributed Energy Storage in the Electric Grid 1. Executive ... For the purpose of this review, DES is defined as an energy storage element or system ...

  2. Inauguration SC

    ScienceCinema (OSTI)

    None

    2011-04-25

    Le DG W.Jentschke ouvre l'inauguration du Syncro Cyclotron (8') et remercie Mons. Michaelis qui prend la parole (30') avant Mons. Wilkinson (53') qui parle du futur de la machine avec présentation des dias.

  3. MEMORANDUM OF UNDERSTANDING Among THE UNITED STATES DEPARTMENT...

    Broader source: Energy.gov (indexed) [DOE]

    The proposed HVDC transmission line would originate at Des Cantons, Quebec, Canada, cross the U.S.-Canada border, and terminate at a location in southern New Hampshire. The Project ...

  4. Information Meeting- Education

    ScienceCinema (OSTI)

    None

    2011-04-25

    Suite à un circulaire, Messieurs Goldschmidt et Ullmann donnent plus d'information et attendent des questions/réponses concernant les problèmes d'éducation d'enfants

  5. Gestational exposure to diethylstilbestrol alters cardiac structure/function, protein expression and DNA methylation in adult male mice progeny

    SciTech Connect (OSTI)

    Haddad, Rami, E-mail: rami.haddad@mail.mcgill.ca [Lady Davis Institute for Medical Research, Jewish General Hospital, 3755 chemin Cote Ste Catherine, Montral, Qubec, Canada H3T 1E2 (Canada) [Lady Davis Institute for Medical Research, Jewish General Hospital, 3755 chemin Cote Ste Catherine, Montral, Qubec, Canada H3T 1E2 (Canada); Division of Experimental Medicine, Department of Medicine, McGill University, 850 Sherbrooke Street, Montral, Qubec, Canada H3A 1A2 (Canada); Kasneci, Amanda, E-mail: amanda.kasneci@mail.mcgill.ca [Lady Davis Institute for Medical Research, Jewish General Hospital, 3755 chemin Cote Ste Catherine, Montral, Qubec, Canada H3T 1E2 (Canada)] [Lady Davis Institute for Medical Research, Jewish General Hospital, 3755 chemin Cote Ste Catherine, Montral, Qubec, Canada H3T 1E2 (Canada); Mepham, Kathryn, E-mail: katherine.mepham@mail.mcgill.ca [Lady Davis Institute for Medical Research, Jewish General Hospital, 3755 chemin Cote Ste Catherine, Montral, Qubec, Canada H3T 1E2 (Canada) [Lady Davis Institute for Medical Research, Jewish General Hospital, 3755 chemin Cote Ste Catherine, Montral, Qubec, Canada H3T 1E2 (Canada); Division of Experimental Medicine, Department of Medicine, McGill University, 850 Sherbrooke Street, Montral, Qubec, Canada H3A 1A2 (Canada); Sebag, Igal A., E-mail: igal.sebag@mcgill.ca [Division of Cardiology, Jewish General Hospital, 3755 chemin Cote Ste Catherine, Montral, Qubec, Canada H3T 1E2 (Canada); and others

    2013-01-01

    Pregnant women, and thus their fetuses, are exposed to many endocrine disruptor compounds (EDCs). Fetal cardiomyocytes express sex hormone receptors making them potentially susceptible to re-programming by estrogenizing EDCs. Diethylstilbestrol (DES) is a proto-typical, non-steroidal estrogen. We hypothesized that changes in adult cardiac structure/function after gestational exposure to the test compound DES would be a proof in principle for the possibility of estrogenizing environmental EDCs to also alter the fetal heart. Vehicle (peanut oil) or DES (0.1, 1.0 and 10.0 ?g/kg/da.) was orally delivered to pregnant C57bl/6n dams on gestation days 11.514.5. At 3 months, male progeny were left sedentary or were swim trained for 4 weeks. Echocardiography of isoflurane anesthetized mice revealed similar cardiac structure/function in all sedentary mice, but evidence of systolic dysfunction and increased diastolic relaxation after swim training at higher DES doses. The calcium homeostasis proteins, SERCA2a, phospholamban, phospho-serine 16 phospholamban and calsequestrin 2, are important for cardiac contraction and relaxation. Immunoblot analyses of ventricle homogenates showed increased expression of SERCA2a and calsequestrin 2 in DES mice and greater molecular remodeling of these proteins and phospho-serine 16 phospholamban in swim trained DES mice. DES increased cardiac DNA methyltransferase 3a expression and DNA methylation in the CpG island within the calsequestrin 2 promoter in heart. Thus, gestational DES epigenetically altered ventricular DNA, altered cardiac function and expression, and reduced the ability of adult progeny to cardiac remodel when physically challenged. We conclude that gestational exposure to estrogenizing EDCs may impact cardiac structure/function in adult males. -- Highlights: ? Gestational DES changes cardiac SERCA2a and CASQ2 expression. ? Echocardiography identified systolic dysfunction and increased diastolic relaxation. ? DES increased DNMT

  6. Personnel

    ScienceCinema (OSTI)

    None

    2011-04-25

    Le président du conseil M.Doran explique la décision que le conseil du Cern vient de prendre sur la 4.étape du régime complémentaire des pensions. Le président du comité des finances le Dr.Andersen ainsi que le Prof.Connor(?) prennent aussi la parole

  7. Senior Staff Meeting

    ScienceCinema (OSTI)

    None

    2011-04-25

    Herbert Lengler fait l'introduction et remercie le DG, les directeurs et le vice président de l'association du personnel pour leur présence. Il parlera des activités depuis la dernière réunion et fera des commentaires sur l'"Abragam Commitee Final Report". Une discussion suivra sur plusieurs points importants.

  8. Spectroscopic Needs for Imaging Dark Energy Experiments

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Newman, Jeffrey A.; Slosar, Anze; Abate, Alexandra; Abdalla, Filipe B.; Allam, Sahar; Allen, Steven W.; Ansari, Reza; Bailey, Stephen; Barkhouse, Wayne A.; Beers, Timothy C.; et al

    2015-03-15

    scatter further, enhancing the science return from planned experiments greatly (increasing the Dark Energy Task Force figure of merit by up to ~50%); Options: This spectroscopy will most efficiently be done by covering as much of the optical and near-infrared spectrum as possible at modestly high spectral resolution (λ/Δλ > ~3000), while maximizing the telescope collecting area, field of view on the sky, and multiplexing of simultaneous spectra. The most efficient instrument for this would likely be either the proposed GMACS/MANIFEST spectrograph for the Giant Magellan Telescope or the OPTIMOS spectrograph for the European Extremely Large Telescope, depending on actual properties when built. The PFS spectrograph at Subaru would be next best and available considerably earlier, c. 2018; the proposed ngCFHT and SSST telescopes would have similar capabilities but start later. Other key options, in order of increasing total time required, are the WFOS spectrograph at TMT, MOONS at the VLT, and DESI at the Mayall 4 m telescope (or the similar 4MOST and WEAVE projects); of these, only DESI, MOONS, and PFS are expected to be available before 2020. Table 2-3 of this white paper summarizes the observation time required at each facility for strawman training samples. To attain secure redshift measurements for a high fraction of targeted objects and cover the full redshift span of future experiments, additional near-infrared spectroscopy will also be required; this is best done from space, particularly with WFIRST-2.4 and JWST; Calibration: The first several moments of redshift distributions (the mean, RMS redshift dispersion, etc.), must be known to high accuracy for cosmological constraints not to be systematics-dominated (equivalently, the moments of the distribution of differences between photometric and true redshifts could be determined instead). The ultimate goal of calibration is to characterize these moments for every subsample used in analyses - i.e., to minimize the

  9. Spectroscopic Needs for Imaging Dark Energy Experiments

    SciTech Connect (OSTI)

    Newman, Jeffrey A.; Slosar, Anze; Abate, Alexandra; Abdalla, Filipe B.; Allam, Sahar; Allen, Steven W.; Ansari, Reza; Bailey, Stephen; Barkhouse, Wayne A.; Beers, Timothy C.; Blanton, Michael R.; Brodwin, Mark; Brownstein, Joel R.; Brunner, Robert J.; Carrasco-Kind, Matias; Cervantes-Cota, Jorge; Chisari, Nora Elisa; Colless, Matthew; Comparat, Johan; Coupon, Jean; Cheu, Elliott; Cunha, Carlos E.; de la Macorra, Alex; DellAntonio, Ian P.; Frye, Brenda L.; Gawiser, Eric J.; Gehrels, Neil; Grady, Kevin; Hagen, Alex; Hall, Patrick B.; Hearin, Andrew P.; Hildebrandt, Hendrik; Hirata, Christopher M.; Ho, Shirley; Honscheid, Klaus; Huterer, Dragan; Ivezic, Zeljko; Kneib, Jean -Paul; Kruk, Jeffrey W.; Lahav, Ofer; Mandelbaum, Rachel; Marshall, Jennifer L.; Matthews, Daniel J.; Menard, Brice; Miquel, Ramon; Moniez, Marc; Moos, H. W.; Moustakas, John; Papovich, Casey; Peacock, John A.; Park, Changbom; Rhodes, Jason; Sadeh, Iftach; Schmidt, Samuel J.; Stern, Daniel K.; Tyson, J. Anthony; von der Linden, Anja; Wechsler, Risa H.; Wood-Vasey, W. M.; Zentner, A.

    2015-03-15

    , enhancing the science return from planned experiments greatly (increasing the Dark Energy Task Force figure of merit by up to ~50%); Options: This spectroscopy will most efficiently be done by covering as much of the optical and near-infrared spectrum as possible at modestly high spectral resolution (?/?? > ~3000), while maximizing the telescope collecting area, field of view on the sky, and multiplexing of simultaneous spectra. The most efficient instrument for this would likely be either the proposed GMACS/MANIFEST spectrograph for the Giant Magellan Telescope or the OPTIMOS spectrograph for the European Extremely Large Telescope, depending on actual properties when built. The PFS spectrograph at Subaru would be next best and available considerably earlier, c. 2018; the proposed ngCFHT and SSST telescopes would have similar capabilities but start later. Other key options, in order of increasing total time required, are the WFOS spectrograph at TMT, MOONS at the VLT, and DESI at the Mayall 4 m telescope (or the similar 4MOST and WEAVE projects); of these, only DESI, MOONS, and PFS are expected to be available before 2020. Table 2-3 of this white paper summarizes the observation time required at each facility for strawman training samples. To attain secure redshift measurements for a high fraction of targeted objects and cover the full redshift span of future experiments, additional near-infrared spectroscopy will also be required; this is best done from space, particularly with WFIRST-2.4 and JWST; Calibration: The first several moments of redshift distributions (the mean, RMS redshift dispersion, etc.), must be known to high accuracy for cosmological constraints not to be systematics-dominated (equivalently, the moments of the distribution of differences between photometric and true redshifts could be determined instead). The ultimate goal of calibration is to characterize these moments for every subsample used in analyses - i.e., to minimize the uncertainty in their mean

  10. Stellar kinematics and metallicities in the ultra-faint dwarf galaxy Reticulum II

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Simon, J. D.

    2015-07-23

    With this study, we present Magellan/M2FS, Very Large Telescope/GIRAFFE, and Gemini South/GMOS spectroscopy of the newly discovered Milky Way satellite Reticulum II. Based on the spectra of 25 Ret II member stars selected from Dark Energy Survey imaging, we measure a mean heliocentric velocity ofmore » $$62.8\\pm 0.5\\;\\mathrm{km}\\;{{\\rm{s}}}^{-1}$$ and a velocity dispersion of $$3.3\\pm 0.7\\;\\mathrm{km}\\;{{\\rm{s}}}^{-1}$$. The mass-to-light ratio of Ret II within its half-light radius is $$470\\pm 210\\ {M}_{\\odot }/{L}_{\\odot }$$, demonstrating that it is a strongly dark matter-dominated system. Despite its spatial proximity to the Magellanic Clouds, the radial velocity of Ret II differs from that of the LMC and SMC by 199 and 83 $$\\mathrm{km}\\ {{\\rm{s}}}^{-1}$$, respectively, suggesting that it is not gravitationally bound to the Magellanic system. The likely member stars of Ret II span 1.3 dex in metallicity, with a dispersion of 0.28 ± 0.09 dex, and we identify several extremely metal-poor stars with $${\\rm{[Fe/H]}}\\lt -3$$. In combination with its luminosity, size, and ellipticity, these results confirm that Ret II is an ultra-faint dwarf galaxy. With a mean metallicity of $${\\rm{[Fe/H]}}=-2.65\\pm 0.07$$, Ret II matches Segue 1 as the most metal-poor galaxy known. Although Ret II is the third-closest dwarf galaxy to the Milky Way, the line-of-sight integral of the dark matter density squared is $${\\mathrm{log}}_{10}(J)=18.8\\pm 0.6\\;\\;\\mathrm{GeV}{\\;}^{2}\\;{\\mathrm{cm}}^{-5}\\;$$ within 0fdg2, indicating that the predicted gamma-ray flux from dark matter annihilation in Ret II is lower than that of several other dwarf galaxies.« less

  11. Structural and functional characterization of human and murine C5a anaphylatoxins

    SciTech Connect (OSTI)

    Schatz-Jakobsen, Janus Asbjrn; Yatime, Laure Larsen, Casper; Petersen, Steen Vang; Klos, Andreas; Andersen, Gregers Rom

    2014-06-01

    The structure of the human C5aR antagonist, C5a-A8, reveals a three-helix bundle conformation similar to that observed for human C5a-desArg, whereas murine C5a and C5a-desArg both form the canonical four-helix bundle. These conformational differences are discussed in light of the differential C5aR activation properties observed for the human and murine complement anaphylatoxins across species. Complement is an ancient part of the innate immune system that plays a pivotal role in protection against invading pathogens and helps to clear apoptotic and necrotic cells. Upon complement activation, a cascade of proteolytic events generates the complement effectors, including the anaphylatoxins C3a and C5a. Signalling through their cognate G-protein coupled receptors, C3aR and C5aR, leads to a wide range of biological events promoting inflammation at the site of complement activation. The function of anaphylatoxins is regulated by circulating carboxypeptidases that remove their C-terminal arginine residue, yielding C3a-desArg and C5a-desArg. Whereas human C3a and C3a-desArg adopt a canonical four-helix bundle fold, the conformation of human C5a-desArg has recently been described as a three-helix bundle. Here, the crystal structures of an antagonist version of human C5a, A8{sup ?7173}, and of murine C5a and C5a-desArg are reported. Whereas A8{sup ?7173} adopts a three-helix bundle conformation similar to human C5a-desArg, the two murine proteins form a four-helix bundle. A cell-based functional assay reveals that murine C5a-desArg, in contrast to its human counterpart, exerts the same level of activition as murine C5a on its cognate receptor. The role of the different C5a conformations is discussed in relation to the differential activation of C5a receptors across species.

  12. Digging deeper into the Southern skies: A compact Milky Way companion discovered in first-year Dark Energy Survey data

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Luque, E.

    2016-02-09

    Here, the Dark Energy Survey (DES) is a 5000 sq. degree survey in the southern hemisphere, which is rapidly reducing the existing north-south asymmetry in the census of MW satellites and other stellar substructure. We use the first-year DES data down to previously unprobed photometric depths to search for stellar systems in the Galactic halo, therefore complementing the previous analysis of the same data carried out by our group earlier this year. Our search is based on a matched filter algorithm that produces stellar density maps consistent with stellar population models of various ages, metallicities, and distances over the surveymore » area. The most conspicuous density peaks in these maps have been identified automatically and ranked according to their significance and recurrence for different input models. We report the discovery of one additional stellar system besides those previously found by several authors using the same first-year DES data. The object is compact, and consistent with being dominated by an old and metal-poor population. DES J0034-4902 is found at high significance and appears in the DES images as a compact concentration of faint blue point sources at ~ 87 {kpc}.« less

  13. DESAlert: Enabling real-time transient follow-up with Dark Energy Survey data

    SciTech Connect (OSTI)

    Poci, A.

    2015-04-12

    The Dark Energy Survey (DES) is currently undertaking an observational program imaging 1/4 of the southern hemisphere sky with unprecedented photometric accuracy. In the process of observing millions of faint stars and galaxies to constrain the parameters of the dark energy equation of state, the DES will obtain pre-discovery images of the regions surrounding an estimated 100 gamma-ray bursts (GRBs) over five years. Once GRBs are detected by, e.g., the Swift satellite, the DES data will be extremely useful for follow-up observations by the transient astronomy community. We describe a recently-commissioned suite of software that listens continuously for automated notices of GRB activity, collates useful information from archival DES data, and promulgates relevant data products back to the community in near-real-time. Of particular importance are the opportunities that DES data provide for relative photometry of GRBs or their afterglows, as well as for identifying key characteristics (e.g., photometric redshifts) of potential GRB host galaxies. We provide the functional details of the DESAlert software as it presently operates, as well as the data products that it produces, and we show sample results from the application of DESAlert to several previously-detected GRBs.

  14. THE SMALL ISOLATED GAS-RICH IRREGULAR DWARF (SIGRID) GALAXY SAMPLE: DESCRIPTION AND FIRST RESULTS

    SciTech Connect (OSTI)

    Nicholls, David C.; Dopita, Michael A.; Jerjen, Helmut; Meurer, Gerhardt R.

    2011-09-15

    Using an optically unbiased selection process based on the HIPASS neutral hydrogen survey, we have selected a sample of 83 spatially isolated, gas-rich dwarf galaxies in the southern hemisphere with cz between 350 and 1650 km s{sup -1}, and with R-band luminosities and H I masses less than that of the Small Magellanic Cloud. The sample is an important population of dwarf galaxies in the local universe, all with ongoing star formation, and most of which have no existing spectroscopic data. We are measuring the chemical abundances of these galaxies, using the integral-field spectrograph on the Australian National University 2.3 m telescope, the Wide-Field Spectrograph. This paper describes our survey criteria and procedures, lists the survey sample, and reports on initial observations.

  15. A DYNAMICAL SIGNATURE OF MULTIPLE STELLAR POPULATIONS IN 47 TUCANAE

    SciTech Connect (OSTI)

    Richer, Harvey B.; Heyl, Jeremy; Anderson, Jay; Kalirai, Jason S.; Shara, Michael M.; Dotter, Aaron; Fahlman, Gregory G.; Rich, R. Michael E-mail: heyl@phas.ubc.ca E-mail: jkalarai@stsci.edu E-mail: aaron.dotter@gmail.com E-mail: rmr@astro.ucla.edu

    2013-07-01

    Based on the width of its main sequence, and an actual observed split when viewed through particular filters, it is widely accepted that 47 Tucanae contains multiple stellar populations. In this contribution, we divide the main sequence of 47 Tuc into four color groups, which presumably represent stars of various chemical compositions. The kinematic properties of each of these groups are explored via proper motions, and a strong signal emerges of differing proper-motion anisotropies with differing main-sequence color; the bluest main-sequence stars exhibit the largest proper-motion anisotropy which becomes undetectable for the reddest stars. In addition, the bluest stars are also the most centrally concentrated. A similar analysis for Small Magellanic Cloud stars, which are located in the background of 47 Tuc on our frames, yields none of the anisotropy exhibited by the 47 Tuc stars. We discuss implications of these results for possible formation scenarios of the various populations.

  16. A HIGH STELLAR OBLIQUITY IN THE WASP-7 EXOPLANETARY SYSTEM

    SciTech Connect (OSTI)

    Albrecht, Simon; Winn, Joshua N.; Hirano, Teruyuki; Butler, R. Paul; Crane, Jeffrey D.; Shectman, Stephen A.; Thompson, Ian B.; Wittenmyer, Robert A.

    2012-01-10

    We measure a tilt of 86 Degree-Sign {+-} 6 Degree-Sign between the sky projections of the rotation axis of the WASP-7 star and the orbital axis of its close-in giant planet. This measurement is based on observations of the Rossiter-McLaughlin (RM) effect with the Planet Finder Spectrograph on the Magellan II telescope. The result conforms with the previously noted pattern among hot-Jupiter hosts, namely, that the hosts lacking thick convective envelopes have high obliquities. Because the planet's trajectory crosses a wide range of stellar latitudes, observations of the RM effect can in principle reveal the stellar differential rotation profile; however, with the present data the signal of differential rotation could not be detected. The host star is found to exhibit radial-velocity noise ({sup s}tellar jitter{sup )} with an amplitude of Almost-Equal-To 30 m s{sup -1} over a timescale of days.

  17. FORMATION OF FULLERENES IN H-CONTAINING PLANETARY NEBULAE

    SciTech Connect (OSTI)

    GarcIa-Hernandez, D. A.; Manchado, A.; Stanghellini, L.; Shaw, R. A.; Villaver, E.; Szczerba, R.; Perea-Calderon, J. V. E-mail: amt@iac.e E-mail: shaw@noao.ed E-mail: eva.villaver@uam.e E-mail: Jose.Perea@sciops.esa.in

    2010-11-20

    Hydrogen depleted environments are considered an essential requirement for the formation of fullerenes. The recent detection of C{sub 60} and C{sub 70} fullerenes in what was interpreted as the hydrogen-poor inner region of a post-final helium shell flash planetary nebula (PN) seemed to confirm this picture. Here, we present strong evidence that challenges the current paradigm regarding fullerene formation, showing that it can take place in circumstellar environments containing hydrogen. We report the simultaneous detection of polycyclic aromatic hydrocarbons (PAHs) and fullerenes toward C-rich and H-containing PNe belonging to environments with very different chemical histories such as our own Galaxy and the Small Magellanic Cloud. We suggest that PAHs and fullerenes may be formed by the photochemical processing of hydrogenated amorphous carbon. These observations suggest that modifications may be needed to our current understanding of the chemistry of large organic molecules as well as the chemical processing in space.

  18. A detailed analysis of the HD 73526 2:1 resonant planetary system

    SciTech Connect (OSTI)

    Wittenmyer, Robert A.; Horner, Jonathan; Tinney, C. G.; Salter, G. S.; Bailey, J.; Wright, D.; Tan, Xianyu; Lee, Man Hoi; Butler, R. P.; Arriagada, P.; Carter, B. D.; Jones, H. R. A.; O'Toole, S. J.; Crane, J. D.; Schectman, S. A.; Thompson, I.; Minniti, D.; Diaz, M.

    2014-01-10

    We present six years of new radial velocity data from the Anglo-Australian and Magellan Telescopes on the HD 73526 2:1 resonant planetary system. We investigate both Keplerian and dynamical (interacting) fits to these data, yielding four possible configurations for the system. The new data now show that both resonance angles are librating, with amplitudes of 40° and 60°, respectively. We then perform long-term dynamical stability tests to differentiate these solutions, which only differ significantly in the masses of the planets. We show that while there is no clearly preferred system inclination, the dynamical fit with i = 90° provides the best combination of goodness-of-fit and long-term dynamical stability.

  19. The origin of the X-ray emission from the high-velocity cloud MS30.7–81.4–118

    SciTech Connect (OSTI)

    Henley, David B.; Shelton, Robin L.; Kwak, Kyujin E-mail: rls@physast.uga.edu

    2014-08-10

    A soft X-ray enhancement has recently been reported toward the high-velocity cloud MS30.7–81.4–118 (MS30.7), a constituent of the Magellanic Stream. In order to investigate the origin of this enhancement, we have analyzed two overlapping XMM-Newton observations of this cloud. We find that the X-ray enhancement is ∼6' or ∼100 pc across, and is concentrated to the north and west of the densest part of the cloud. We modeled the X-ray enhancement with a variety of spectral models. A single-temperature equilibrium plasma model yields a temperature of (3.69{sub −0.44}{sup +0.47})×10{sup 6} K and a 0.4-2.0 keV luminosity of 7.9 × 10{sup 33} erg s{sup –1}. However, this model underpredicts the on-enhancement emission around 1 keV, which may indicate the additional presence of hotter plasma (T ≳ 10{sup 7} K), or that recombination emission is important. We examined several different physical models for the origin of the X-ray enhancement. We find that turbulent mixing of cold cloud material with hot ambient material, compression or shock heating of a hot ambient medium, and charge exchange reactions between cloud atoms and ions in a hot ambient medium all lead to emission that is too faint. In addition, shock heating in a cool or warm medium leads to emission that is too soft (for reasonable cloud speeds). We find that magnetic reconnection could plausibly power the observed X-ray emission, but resistive magnetohydrodynamical simulations are needed to test this hypothesis. If magnetic reconnection is responsible for the X-ray enhancement, the observed spectral properties could potentially constrain the magnetic field in the vicinity of the Magellanic Stream.

  20. MONSTER IN THE DARK: THE ULTRALUMINOUS GRB 080607 AND ITS DUSTY ENVIRONMENT

    SciTech Connect (OSTI)

    Perley, D. A.; Morgan, A. N.; Miller, A. A.; Bloom, J. S.; Cenko, S. B.; Li, W.; Filippenko, A. V.; Butler, N. R.; Christian, P.; Updike, A.; Hartmann, D. H.; Yuan, F.; Akerlof, C. W.; Prochaska, J. X.; Tanvir, N. R.; Levan, A. J.; Milne, P.; Rujopakarn, W.; Rykoff, E. S.

    2011-02-15

    We present early-time optical through infrared photometry of the bright Swift gamma-ray burst (GRB) 080607, starting only 6 s following the initial trigger in the rest frame. Complemented by our previously published spectroscopy, this high-quality photometric data set allows us to solve for the extinction properties of the redshift 3.036 sightline, giving perhaps the most detailed information to date on the ultraviolet continuum absorption properties of any sightline outside our Local Group. The extinction properties are not adequately modeled by any ordinary extinction template (including the average Milky Way, Large Magellanic Cloud, and Small Magellanic Cloud curves), partially because the 2175 A feature (while present) is weaker by about a factor of two than when seen under similar circumstances locally. However, the spectral energy distribution is exquisitely fitted by the more general Fitzpatrick and Massa parameterization of Local-Group extinction, putting it in the same family as some peculiar Milky Way extinction curves. After correcting for this (considerable, A{sub V} = 3.3 {+-} 0.4 mag) extinction, GRB 080607 is revealed to have been among the most optically luminous events ever observed, comparable to the naked-eye burst GRB 080319B. Its early peak time (t{sub rest} < 6 s) indicates a high initial Lorentz factor ({Gamma}>600), while the extreme luminosity may be explained in part by a large circumburst density. Only because of its early high luminosity could the afterglow of GRB 080607 be studied in such detail in spite of the large attenuation and great distance, making this burst an excellent prototype for the understanding of other highly obscured extragalactic objects, and of the class of 'dark' GRBs in particular.

  1. HD106906b: A PLANETARY-MASS COMPANION OUTSIDE A MASSIVE DEBRIS DISK

    SciTech Connect (OSTI)

    Bailey, Vanessa; Reiter, Megan; Morzinski, Katie; Males, Jared; Su, Kate Y. L.; Hinz, Philip M.; Stark, Daniel; Close, Laird M.; Follette, Katherine B.; Rodigas, Timothy; Meshkat, Tiffany; Kenworthy, Matthew; Mamajek, Eric; Briguglio, Runa; Puglisi, Alfio; Xompero, Marco; Weinberger, Alycia J.

    2014-01-01

    We report the discovery of a planetary-mass companion, HD106906 b, with the new Magellan Adaptive Optics (MagAO) + Clio2 system. The companion is detected with Clio2 in three bands: J, K{sub S} , and L', and lies at a projected separation of 7.''1 (650 AU). It is confirmed to be comoving with its 13 2 Myr F5 host using Hubble Space Telescope Advanced Camera for Surveys astrometry over a time baseline of 8.3 yr. DUSTY and COND evolutionary models predict that the companion's luminosity corresponds to a mass of 11 2 M {sub Jup}, making it one of the most widely separated planetary-mass companions known. We classify its Magellan/Folded-Port InfraRed Echellette J/H/K spectrum as L2.5 1; the triangular H-band morphology suggests an intermediate surface gravity. HD106906 A, a pre-main-sequence Lower Centaurus Crux member, was initially targeted because it hosts a massive debris disk detected via infrared excess emission in unresolved Spitzer imaging and spectroscopy. The disk emission is best fit by a single component at 95 K, corresponding to an inner edge of 15-20 AU and an outer edge of up to 120 AU. If the companion is on an eccentric (e > 0.65) orbit, it could be interacting with the outer edge of the disk. Close-in, planet-like formation followed by scattering to the current location would likely disrupt the disk and is disfavored. Furthermore, we find no additional companions, though we could detect similar-mass objects at projected separations >35 AU. In situ formation in a binary-star-like process is more probable, although the companion-to-primary mass ratio, at <1%, is unusually small.

  2. SWIFT X-RAY OBSERVATIONS OF CLASSICAL NOVAE. II. THE SUPER SOFT SOURCE SAMPLE

    SciTech Connect (OSTI)

    Schwarz, Greg J.; Ness, Jan-Uwe; Osborne, J. P.; Page, K. L.; Evans, P. A.; Beardmore, A. P.; Walter, Frederick M.; Andrew Helton, L.; Woodward, Charles E.; Bode, Mike; Starrfield, Sumner; Drake, Jeremy J.

    2011-12-01

    The Swift gamma-ray burst satellite is an excellent facility for studying novae. Its rapid response time and sensitive X-ray detector provides an unparalleled opportunity to investigate the previously poorly sampled evolution of novae in the X-ray regime. This paper presents Swift observations of 52 Galactic/Magellanic Cloud novae. We included the X-Ray Telescope (0.3-10 keV) instrument count rates and the UltraViolet and Optical Telescope (1700-8000 A) filter photometry. Also included in the analysis are the publicly available pointed observations of 10 additional novae the X-ray archives. This is the largest X-ray sample of Galactic/Magellanic Cloud novae yet assembled and consists of 26 novae with Super Soft X-ray emission, 19 from Swift observations. The data set shows that the faster novae have an early hard X-ray phase that is usually missing in slower novae. The Super Soft X-ray phase occurs earlier and does not last as long in fast novae compared to slower novae. All the Swift novae with sufficient observations show that novae are highly variable with rapid variability and different periodicities. In the majority of cases, nuclear burning ceases less than three years after the outburst begins. Previous relationships, such as the nuclear burning duration versus t{sub 2} or the expansion velocity of the eject and nuclear burning duration versus the orbital period, are shown to be poorly correlated with the full sample indicating that additional factors beyond the white dwarf mass and binary separation play important roles in the evolution of a nova outburst. Finally, we confirm two optical phenomena that are correlated with strong, soft X-ray emission which can be used to further increase the efficiency of X-ray campaigns.

  3. A search for stars of very low metal abundance. VI. Detailed abundances of 313 metal-poor stars

    SciTech Connect (OSTI)

    Roederer, Ian U.; Preston, George W.; Thompson, Ian B.; Shectman, Stephen A.; Burley, Gregory S.; Kelson, Daniel D.; Sneden, Christopher

    2014-06-01

    We present radial velocities, equivalent widths, model atmosphere parameters, and abundances or upper limits for 53 species of 48 elements derived from high resolution optical spectroscopy of 313 metal-poor stars. A majority of these stars were selected from the metal-poor candidates of the HK Survey of Beers, Preston, and Shectman. We derive detailed abundances for 61% of these stars for the first time. Spectra were obtained during a 10 yr observing campaign using the Magellan Inamori Kyocera Echelle spectrograph on the Magellan Telescopes at Las Campanas Observatory, the Robert G. Tull Coudé Spectrograph on the Harlan J. Smith Telescope at McDonald Observatory, and the High Resolution Spectrograph on the Hobby-Eberly Telescope at McDonald Observatory. We perform a standard LTE abundance analysis using MARCS model atmospheres, and we apply line-by-line statistical corrections to minimize systematic abundance differences arising when different sets of lines are available for analysis. We identify several abundance correlations with effective temperature. A comparison with previous abundance analyses reveals significant differences in stellar parameters, which we investigate in detail. Our metallicities are, on average, lower by ≈0.25 dex for red giants and ≈0.04 dex for subgiants. Our sample contains 19 stars with [Fe/H] ≤–3.5, 84 stars with [Fe/H] ≤–3.0, and 210 stars with [Fe/H] ≤–2.5. Detailed abundances are presented here or elsewhere for 91% of the 209 stars with [Fe/H] ≤–2.5 as estimated from medium resolution spectroscopy by Beers, Preston, and Shectman. We will discuss the interpretation of these abundances in subsequent papers.

  4. DISCOVERY OF H? EMISSION FROM THE CLOSE COMPANION INSIDE THE GAP OF TRANSITIONAL DISK HD142527

    SciTech Connect (OSTI)

    Close, L. M.; Follette, K. B.; Males, J. R.; Apai, D.; Morzinski, K.; Rodigas, T. J.; Hinz, P.; Bailey, V.; Puglisi, A.; Xompero, M.; Briguglio, R.; Najita, J.; Weinberger, A. J.

    2014-02-01

    We utilized the new high-order 585 actuator Magellan Adaptive Optics system (MagAO) to obtain very high-resolution visible light images of HD142527 with MagAO's VisAO science camera. In the median seeing conditions of the 6.5m Magellan telescope (0.''50.''7), we find MagAO delivers 24%-19% Strehl at H? (0.656 ?m). We detect a faint companion (HD142527B) embedded in this young transitional disk system at just 86.3 1.9 mas (?12 AU) from the star. The companion is detected in both H? and a continuum filter (?mag = 6.33 0.20 mag at H? and 7.50 0.25 mag in the continuum filter). This provides confirmation of the tentative companion discovered by Biller and co-workers with sparse aperture masking at the 8m Very Large Telescope. The H? emission from the ?0.25 solar mass companion (EW = 180 ) implies a mass accretion rate of ?5.9 10{sup 10} M {sub sun} yr{sup 1} and a total accretion luminosity of 1.2% L {sub sun}. Assuming a similar accretion rate, we estimate that a 1 Jupiter mass gas giant could have considerably better (50-1000) planet/star contrasts at H? than at the H band (COND models) for a range of optical extinctions (3.4-0 mag). We suggest that ?0.5-5 M {sub jup} extrasolar planets in their gas accretion phase could be much more luminous at H? than in the NIR. This is the motivation for our new MagAO GAPplanetS survey for extrasolar planets.

  5. THE COSMOS ACTIVE GALACTIC NUCLEUS SPECTROSCOPIC SURVEY. I. XMM-NEWTON COUNTERPARTS

    SciTech Connect (OSTI)

    Trump, Jonathan R.; Impey, Chris D.; Gabor, Jared; Kelly, Brandon C.; Elvis, Martin; Huchra, John P.; Civano, Francesca; Hao, Heng; McCarthy, Patrick J.; Scoville, Nick Z.; Smolcic, Vernesa; Brusa, Marcella; Cappelluti, Nico; Hasinger, Gunther; Salvato, Mara; Capak, Peter; Comastri, Andrea; Jahnke, Knud; Schinnerer, Eva; Lilly, Simon J.

    2009-05-10

    We present optical spectroscopy for an X-ray and optical flux-limited sample of 677 XMM-Newton selected targets covering the 2 deg{sup 2} Cosmic Evolution Survey field, with a yield of 485 high-confidence redshifts. The majority of the spectra were obtained over three seasons (2005-2007) with the Inamori Magellan Areal Camera and Spectrograph instrument on the Magellan (Baade) telescope. We also include in the sample previously published Sloan Digital Sky Survey spectra and supplemental observations with MMT/Hectospec. We detail the observations and classification analyses. The survey is 90% complete to flux limits of f {sub 0.5-10keV} > 8 x 10{sup -16} erg cm{sup -2} s{sup -1} and i {sup +} {sub AB} < 22, where over 90% of targets have high-confidence redshifts. Making simple corrections for incompleteness due to redshift and spectral type allows for a description of the complete population to i {sup +} {sub AB} < 23. The corrected sample includes a 57% broad emission line (Type 1, unobscured) active galactic nucleus (AGN) at 0.13 < z < 4.26, 25% narrow emission line (Type 2, obscured) AGN at 0.07 < z < 1.29, and 18% absorption line (host-dominated, obscured) AGN at 0 < z < 1.22 (excluding the stars that made up 4% of the X-ray targets). We show that the survey's limits in X-ray and optical fluxes include nearly all X-ray AGNs (defined by L {sub 0.5-10keV} > 3 x 10{sup 42} erg s{sup -1}) to z < 1, of both optically obscured and unobscured types. We find statistically significant evidence that the obscured-to-unobscured AGN ratio at z < 1 increases with redshift and decreases with luminosity.

  6. Air-gap gating of MgZnO/ZnO heterostructures

    SciTech Connect (OSTI)

    Tambo, T.; Falson, J. Kozuka, Y.; Maryenko, D.; Tsukazaki, A.; Kawasaki, M.

    2014-08-28

    The adaptation of air-gap dielectric based field-effect transistor technology to controlling the MgZnO/ZnO heterointerface confined two-dimensional electron system (2DES) is reported. We find it possible to tune the charge density of the 2DES via a gate electrode spatially separated from the heterostructure surface by a distance of 5??m. Under static gating, the observation of the quantum Hall effect suggests that the charge carrier density remains homogeneous, with the 2DES in the 3?mm square sample the sole conductor. The availability of this technology enables the exploration of the charge carrier density degree of freedom in the pristine sample limit.

  7. Voyage dans le noir. Trous noirs, matière noire, énergie noire et antimatière

    ScienceCinema (OSTI)

    None

    2011-10-06

    Et si nous faisions avec les physiciens un voyage dans le noir ? De l'astrophysique à la physique des particules les trois noirs, la matière noire, l'énergie noire ou l?antimatière intriguent et fascinent. Que sont ces objets qui bousculent nos idées et qui véhiculent parfois des craintes irraisonnées? Luis Alvarez-Gaume, Michael Doser et Christophe Grojean, physiciens du CERN vous invitent à mettre en lumière (!) les constituants de base de la matière et à explorer les mystères de la physique contemporaine. Une soirée lumineuse pour éclairer des concepts et ne plus avoir peur du noir.

  8. Conference B.Bettelheim

    ScienceCinema (OSTI)

    None

    2011-04-25

    Le Dr.Bruno Bettelheim, psychologue américain, d'origine viennoise, a passé son doctorat en psychologie à l'université de Vienne. Il émigra aux Etats-Unis et enseigna la psychologie au Rockford College en Illinois et la psychologie de l'éducation à L'université de Chicago, où il dirigea également l'institut orthogénique Sonia-Shankman pour le traitement des enfants psychotiques. Cet homme a bouleversé la compréhension des relations parents et enfants en y introduisant la psychanalyse. Basé sur ses expériences aux Etats-Unis,il nous parle des changements dans la structure de la famille et ses conséquences pour la relation entre enfants et parents.

  9. Laboratory evaluation of dynamic traffic assignment systems: Requirements, framework, and system design

    SciTech Connect (OSTI)

    Miaou, S.-P.; Pillai, R.S.; Summers, M.S.; Rathi, A.K.; Lieu, H.C.

    1997-01-01

    The success of Advanced Traveler Information 5ystems (ATIS) and Advanced Traffic Management Systems (ATMS) depends on the availability and dissemination of timely and accurate estimates of current and emerging traffic network conditions. Real-time Dynamic Traffic Assignment (DTA) systems are being developed to provide the required timely information. The DTA systems will provide faithful and coherent real-time, pre-trip, and en-route guidance/information which includes routing, mode, and departure time suggestions for use by travelers, ATIS, and ATMS. To ensure the credibility and deployment potential of such DTA systems, an evaluation system supporting all phases of DTA system development has been designed and presented in this paper. This evaluation system is called the DTA System Laboratory (DSL). A major component of the DSL is a ground- truth simulator, the DTA Evaluation System (DES). The DES is envisioned to be a virtual representation of a transportation system in which ATMS and ATIS technologies are deployed. It simulates the driving and decision-making behavior of travelers in response to ATIS and ATMS guidance, information, and control. This paper presents the major evaluation requirements for a DTA Systems, a modular modeling framework for the DES, and a distributed DES design. The modeling framework for the DES is modular, meets the requirements, can be assembled using both legacy and independently developed modules, and can be implemented as a either a single process or a distributed system. The distributed design is extendible, provides for the optimization of distributed performance, and object-oriented design within each distributed component. A status report on the development of the DES and other research applications is also provided.

  10. EVIDENCE FOR THE DISKY ORIGIN OF LUMINOUS VIRGO DWARF ELLIPTICALS FROM THE KINEMATICS OF THEIR GLOBULAR CLUSTER SYSTEMS

    SciTech Connect (OSTI)

    Beasley, Michael A.; Cenarro, A. Javier; Brodie, Jean P. E-mail: cenarro@iac.es E-mail: brodie@ucolick.org

    2009-06-15

    We report evidence for dynamically significant rotation in the globular cluster systems of two luminous Virgo dwarf ellipticals, VCC1261 and VCC1528. Including previous results for VCC1087, the globular cluster systems of all three Virgo dwarf ellipticals studied in detail to date exhibit v {sub rot}/{sigma}{sub los}>1. Taking the rotation seen in the globular clusters as a maximal disk rotation, and accounting for the possible fading of any hypothetical progenitor galaxy, we find all three dwarf elliptical galaxies (dEs) lie on the r-band Tully-Fisher relation. We argue that these data support the hypothesis that luminous dEs are the remnants of transformed disk galaxies. We also obtained deep, longslit data for the stars in VCC1261 and VCC1528. Both these galaxies show rapid rotation in their inner regions, with spatial scales of {approx}0.5 kpc. These rotation velocities are surprisingly similar to those seen in the globular cluster systems. At larger radii, we see little rotation in the dEs themselves. Since our longslit data for Virgo dEs extend out to 1-2 effective radii (typical of deep observations), whereas the globular clusters extend out to 4-7 effective radii, we conclude that nondetections of rotation in many luminous dEs may simply be due to a lack of radial coverage in the stellar data, and that globular clusters represent singularly sensitive probes of the dynamics of dEs. Based on these data, we suggest that gas disks are significant sites of globular cluster formation in the early universe.

  11. The Dark Energy Survey: Prospects for resolved stellar populations

    SciTech Connect (OSTI)

    Rossetto, Bruno M.; Santiago, Basílio X.; Girardi, Léo; Camargo, Julio I. B.; Balbinot, Eduardo; da Costa, Luiz N.; Yanny, Brian; Maia, Marcio A. G.; Makler, Martin; Ogando, Ricardo L. C.; Pellegrini, Paulo S.; Ramos, Beatriz; de Simoni, Fernando; Armstrong, R.; Bertin, E.; Desai, S.; Kuropatkin, N.; Lin, H.; Mohr, J. J.; Tucker, D. L.

    2011-05-06

    Wide angle and deep surveys, regardless of their primary purpose, always sample a large number of stars in the Galaxy and in its satellite system. We here make a forecast of the expected stellar sample resulting from the Dark Energy Survey and the perspectives that it will open for studies of Galactic structure and resolved stellar populations in general. An estimated 1.2 x 108 stars will be sampled in DES grizY filters in the southern equatorial hemisphere. This roughly corresponds to 20% of all DES sources. Most of these stars belong to the stellar thick disk and halo of the Galaxy.

  12. THE DARK ENERGY SURVEY: PROSPECTS FOR RESOLVED STELLAR POPULATIONS

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Rossetto, Bruno M.; Santiago, Baslio X.; Girardi, Lo; Camargo, Julio I. B.; Balbinot, Eduardo; da Costa, Luiz N.; Yanny, Brian; Maia, Marcio A. G.; Makler, Martin; Ogando, Ricardo L. C.; et al

    2011-06-01

    Wide angle and deep surveys, regardless of their primary purpose, always sample a large number of stars in the Galaxy and in its satellite system. We here make a forecast of the expected stellar sample resulting from the Dark Energy Survey and the perspectives that it will open for studies of Galactic structure and resolved stellar populations in general. An estimated 1.2 x 108 stars will be sampled in DES grizY filters in the southern equatorial hemisphere. This roughly corresponds to 20% of all DES sources. Most of these stars belong to the stellar thick disk and halo of themoreGalaxy.less

  13. Dark Energy | Argonne National Laboratory

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Dark Energy Dark Energy The Dark Energy Survey (DES) is a joint project between the U.S. Department of Energy and the National Science Foundation to study the nature of dark matter and dark energy. Dark matter and energy are believed to make up 95 percent of the universe, and their origin and composition are completely unknown. The DES has built a new 520 mega-pixel CCD camera for an existing 4-meter telescope in Chile that will be used for a five-year program of observations. These new

  14. Human Rights

    ScienceCinema (OSTI)

    None

    2011-04-25

    Daniel Meyer, Président de la ligue française de défense de droits de l'homme et du citoyen fait un exposé sur son engagement (politique). Dans la deuxième partie, une avocate brésilienne (en exil)donne un témoignage de la violation des droits de l'homme sous la dictature militaire de son pays; elle a défendu pendant 6 ans des prisonniers politiques.

  15. Effect of transverse current on Andreev bound state

    SciTech Connect (OSTI)

    Takahashi, Y.; Hashimoto, Y.; Yun, D. H.; Kim, S. W.; Nakamura, T.; Iye, Y.; Katsumoto, S.

    2013-12-04

    In a superconductor-normal-superconductor (SNS) structure, the effect of transverse current across the normal part on the transport through Andreev bound states (ABSs) has been examined. Here a ballistic InAs two-dimensional electron system (2DES) is used as the N-layer to form ABSs. At the same time the 2DES has strong spin-orbit interaction, hence there should emerge the spin-Hall effect associated with the transverse current. We have observed strong reduction of characteristic oscillation in the conductance versus bias voltage, which may be attributed to spin polarization due to the spin-Hall effect.

  16. Eia.gov BETA - Data - U.S. Energy Information Administration (EIA)

    U.S. Energy Information Administration (EIA) Indexed Site

    Tableau croisé des definitions English FranÇais Español A B C D E É F G H I J K L M N O P Q R S T U V W X Y Z Parcourir les termes liés aux catégories suivantes: pétrole brut et équivalents liquides de gaz naturel additifs et composés oxygénés Produits pétroliers gaz naturel biocarburant électricité Consultez l'index des termes

  17. Diethylstilbestrol can effectively accelerate estradiol-17-O-glucuronidation, while potently inhibiting estradiol-3-O-glucuronidation

    SciTech Connect (OSTI)

    Zhu, Liangliang; Xiao, Ling; Xia, Yangliu; Zhou, Kun; Wang, Huili; Huang, Minyi; Ge, Guangbo; Wu, Yan; Wu, Ganlin; Yang, Ling

    2015-03-01

    This in vitro study investigates the effects of diethylstilbestrol (DES), a widely used toxic synthetic estrogen, on estradiol-3- and 17-O- (E2-3/17-O) glucuronidation, via culturing human liver microsomes (HLMs) or recombinant UDP-glucuronosyltransferases (UGTs) with DES and E2. DES can potently inhibit E2-3-O-glucuronidation in HLM, a probe reaction for UGT1A1. Kinetic assays indicate that the inhibition follows a competitive inhibition mechanism, with the Ki value of 2.1 ± 0.3 μM, which is less than the possible in vivo level. In contrast to the inhibition on E2-3-O-glucuronidation, the acceleration is observed on E2-17-O-glucuronidation in HLM, in which cholestatic E2-17-O-glucuronide is generated. In the presence of DES (0–6.25 μM), K{sub m} values for E2-17-O-glucuronidation are located in the range of 7.2–7.4 μM, while V{sub max} values range from 0.38 to 1.54 nmol/min/mg. The mechanism behind the activation in HLM is further demonstrated by the fact that DES can efficiently elevate the activity of UGT1A4 in catalyzing E2-17-O-glucuronidation. The presence of DES (2 μM) can elevate V{sub max} from 0.016 to 0.81 nmol/min/mg, while lifting K{sub m} in a much lesser extent from 4.4 to 11 μM. Activation of E2-17-O-glucuronidation is well described by a two binding site model, with K{sub A}, α, and β values of 0.077 ± 0.18 μM, 3.3 ± 1.1 and 104 ± 56, respectively. However, diverse effects of DES towards E2-3/17-O-glucuronidation are not observed in liver microsomes from several common experimental animals. In summary, this study issues new potential toxic mechanisms for DES: potently inhibiting the activity of UGT1A1 and powerfully accelerating the formation of cholestatic E2-17-O-glucuronide by UGT1A4. - Highlights: • E2-3-O-glucuronidation in HLM is inhibited when co-incubated with DES. • E2-17-O-glucuronidation in HLM is stimulated when co-incubated with DES. • Acceleration of E2-17-O-glucuronidationin in HLM by DES is via activating the

  18. Science and Society

    SciTech Connect (OSTI)

    2006-07-18

    "Can nuclear war be controled?"- la guerre nucléaire peut-elle être contrôlée? Tel est le thème de cette conférence avec présentation des dias.

  19. Browse by Discipline -- E-print Network Subject Pathways: Geosciences...

    Office of Scientific and Technical Information (OSTI)

    A B C D E F G H I J K L M N O P Q R S T U V W X Y Z Institut de Biologie Physico-Chimique CNRS, Physico-Chimie Molculaire des Membranes Biologiques Institute of Catalysis and ...

  20. Science and Society

    ScienceCinema (OSTI)

    None

    2011-04-25

    "Can nuclear war be controled?"- la guerre nucléaire peut-elle être contrôlée? Tel est le thème de cette conférence avec présentation des dias.

  1. Press conference

    ScienceCinema (OSTI)

    None

    2011-04-25

    Exposés de plusieurs intervenants de la direction et du conseil, comme le Prof.Ramsey, président du conseil sur l'adhésion récente de la Finlande et le "boom" scientifique des pays de l'est.

  2. Science and Society

    ScienceCinema (OSTI)

    None

    2011-04-25

    Dans une période d'un mois, 2me conférence sur le contrôle d'armes. Le conférencier Drell, américain, parle comme son collègue Worden (AUDIO-1985-005) des problèmes de défense stratégique.

  3. Problem of Questioning

    ScienceCinema (OSTI)

    None

    2011-04-25

    Le Prof.Leprince-Ringuet, chercheur sur le plan scientifique, artistique et humain, parle de la remise en question des hommes et la remise en question scientifique fondamentale ou exemplaire- plusieurs personnes prennent la parole p.ex Jeanmairet, Adam, Gregory. Le Prof.Gregory clot la soirée en remerciant le Prof.Leprince-Ringuet

  4. STELLAR KINEMATICS AND STRUCTURAL PROPERTIES OF VIRGO CLUSTER DWARF EARLY-TYPE GALAXIES FROM THE SMAKCED PROJECT. III. ANGULAR MOMENTUM AND CONSTRAINTS ON FORMATION SCENARIOS

    SciTech Connect (OSTI)

    Toloba, E.; Guhathakurta, P.; Peletier, R. F.; Emsellem, E.; Lisker, T.; Van de Ven, G.; Simon, J. D.; Adams, J. J.; Benson, A. J.; Falcón-Barroso, J.; Ryś, A.; Gorgas, J.; Hensler, G.; Janz, J.; Laurikainen, E.; Salo, H.; Paudel, S.

    2015-02-01

    We analyze the stellar kinematics of 39 dwarf early-type galaxies (dEs) in the Virgo Cluster. Based on the specific stellar angular momentum λ{sub Re} and the ellipticity, we find 11 slow rotators and 28 fast rotators. The fast rotators in the outer parts of the Virgo Cluster rotate significantly faster than fast rotators in the inner parts of the cluster. Moreover, 10 out of the 11 slow rotators are located in the inner 3° (D < 1 Mpc) of the cluster. The fast rotators contain subtle disk-like structures that are visible in high-pass filtered optical images, while the slow rotators do not exhibit these structures. In addition, two of the dEs have kinematically decoupled cores and four more have emission partially filling in the Balmer absorption lines. These properties suggest that Virgo Cluster dEs may have originated from late-type star-forming galaxies that were transformed by the environment after their infall into the cluster. The correlation between λ{sub Re} and the clustercentric distance can be explained by a scenario where low luminosity star-forming galaxies fall into the cluster, their gas is rapidly removed by ram-pressure stripping, although some of it can be retained in their core, their star formation is quenched but their stellar kinematics are preserved. After a long time in the cluster and several passes through its center, the galaxies are heated up and transformed into slow rotating dEs.

  5. Science anc Society

    SciTech Connect (OSTI)

    2006-09-12

    S.P.Worden, membre technique de l'U.S.délégation à Genève pour les négociations sur les armes nucléaires, est physicien, astronome, scientifique et officier de l'armée de l'air. Il parlera des technologies de défense stratégique

  6. 10th Anniversary P.S.

    ScienceCinema (OSTI)

    None

    2011-04-25

    John Adams parle de la préhistoire du P.S. avec présentation des dias. Le DG B.Gregory prend la parole. Les organisateurs présentent sous la direction du "Prof.Ocktette"(?) un sketch très humoristique (p.e.existence de Quark etc.....)

  7. Impressions on Chinas Popular Republic

    ScienceCinema (OSTI)

    None

    2011-04-25

    Le D.G. Jentschke présente le Prof.Yang, née en 1922 en Chine où il a aussi fait ses études; il parle de ses impressions en Chine (p.e. mariage etc....) avec présentation des dias

  8. E-mail et Web : pour une navigation sans risque

    ScienceCinema (OSTI)

    None

    2011-10-06

    Présentation orale en français, support visuel en anglais. À travers des exemples concrets, vous consoliderez vos connaissances et pourrez ainsi réajuster vos habitudes concernant l?utilisation sécurisée de votre boîte e-mail et de votre navigateur Web.

  9. KINEMATIC PROPERTIES AS PROBES OF THE EVOLUTION OF DWARF GALAXIES IN THE VIRGO CLUSTER

    SciTech Connect (OSTI)

    Toloba, E.; Gorgas, J.; De Paz, A. Gil; Boselli, A.; Peletier, R. F.; Yildiz, U.; Cenarro, A. J.; Gadotti, D. A.; Pedraz, S.

    2009-12-10

    We present new observational results on the kinematical, morphological, and stellar population properties of a sample of 21 dEs located both in the Virgo Cluster and in the field, which show that 52% of the dEs (1) are rotationally supported, (2) exhibit structural signs of typical rotating systems such as disks, bars, or spiral arms, (3) are younger (approx3 Gyr) than non-rotating dEs, and (4) are preferentially located either in the outskirts of Virgo or in the field. This evidence is consistent with the idea that rotationally supported dwarfs are late-type spirals or irregulars that recently entered the cluster and lost their gas through a ram pressure stripping event, quenching their star formation and becoming dEs through passive evolution. We also find that all, but one, galaxies without photometric hints for hosting disks are pressure supported and are all situated in the inner regions of the cluster. This suggests a different evolution from the rotationally supported systems. Three different scenarios for these non-rotating galaxies are discussed (in situ formation, harassment, and ram pressure stripping).

  10. Andrei Sakharov

    ScienceCinema (OSTI)

    None

    2011-04-25

    Ce discours donné par Mons.Jonauch qui est né en Tchécoslovaquie et a fait ses études à Leningrad, Moscou et Prague, est organisé par le comité Youri Orlov. Le conférencier parle de Andrei Sakharov, ce physicien et homme soviétique qui fit ses études à Moscou, effectua des recherches sur les armes thermonucléaires et entra à l'Académie des Sciences d'URSS en 1953. Il participa à la mise au point de la bombe à hydrogène, mais s'opposa quelques années plus tard à la poursuite des expériences nucléaires. Il créa en 1970 le comité pour la défense des droits de l'homme ce que lui valut le prix Nobel de la paix en 1975.

  11. CX-002724: Categorical Exclusion Determination

    Broader source: Energy.gov [DOE]

    Area of Interest 3 Deployment of Flex Combined Heat and Power System (Funding Opportunity Announcement 0000016)CX(s) Applied: B3.6Date: 06/21/2010Location(s): Des Plains, IllinoisOffice(s): Energy Efficiency and Renewable Energy, National Energy Technology Laboratory

  12. Meeting LEP

    ScienceCinema (OSTI)

    None

    2011-04-25

    Le DG J.Adams fait l'introduction et présente les deux autres orateurs. Pierre Darriulat qui fait un doscours sur la physique à l'occasion du LEP, Wolfgang Schnell, qui parle du projet de la machine LEP et le DG lui-même contribue avec quelques réflexions. Présentation des dias

  13. Western Dilemma

    ScienceCinema (OSTI)

    None

    2011-04-25

    L'association du personnel présente Anthony Sampson, écrivain connu dans le monde entier par ses nombreux ouvrages et publications (International Harold Tribune, Observer, News Week). Il nous parle du commerce des armes et du Moyen Orient.

  14. Combining Galaxy-Galaxy Lensing and Galaxy Clustering

    SciTech Connect (OSTI)

    Park, Youngsoo; Krause, Elisabeth; Dodelson, Scott; Jain, Bhuvnesh; Amara, Adam; Becker, Matt; Bridle, Sarah; Clampitt, Joseph; Crocce, Martin; Honscheid, Klaus; Gaztanaga, Enrique; Sanchez, Carles; Wechsler, Risa

    2015-01-01

    Combining galaxy-galaxy lensing and galaxy clustering is a promising method for inferring the growth rate of large scale structure, a quantity that will shed light on the mechanism driving the acceleration of the Universe. The Dark Energy Survey (DES) is a prime candidate for such an analysis, with its measurements of both the distribution of galaxies on the sky and the tangential shears of background galaxies induced by these foreground lenses. By constructing an end-to-end analysis that combines large-scale galaxy clustering and small-scale galaxy-galaxy lensing, we also forecast the potential of a combined probes analysis on DES datasets. In particular, we develop a practical approach to a DES combined probes analysis by jointly modeling the assumptions and systematics affecting the different components of the data vector, employing a shared halo model, HOD parametrization, photometric redshift errors, and shear measurement errors. Furthermore, we study the effect of external priors on different subsets of these parameters. We conclude that DES data will provide powerful constraints on the evolution of structure growth in the universe, conservatively/ optimistically constraining the growth function to 8%/4.9% with its first-year data covering 1000 square degrees, and to 4%/2.3% with its full five-year data covering 5000 square degrees.

  15. CX-003043: Categorical Exclusion Determination

    Broader source: Energy.gov [DOE]

    Development of a Training Program for Commercial Building TechniciansCX(s) Applied: A1, A9, A11Date: 07/19/2010Location(s): Des Plaines, IllinoisOffice(s): Energy Efficiency and Renewable Energy, National Energy Technology Laboratory

  16. C.F.von Weizsäcker-High Energy Physics

    ScienceCinema (OSTI)

    None

    2011-04-25

    C.F.von Weizsäcker (1912-2007),physicien,philosophe et "chercheur de paix", prit la décision de faire des études de physique sous l'influence de W.Heisenberg qu'il rencontra en 1927.

  17. Meeting DG's

    ScienceCinema (OSTI)

    None

    2011-04-25

    Le DG J.Adams commente les 3 thèmes de la réunion: 1.) le prochain DG du Cern (qui sera H.Schopper) 2.) le LEP 3.) les conclusions du comité des finances concernant salaires, allocations etc. Discussion entre le DG J.Adams, Mons.Ullmann, chef du personel et l'auditoire

  18. Science anc Society

    ScienceCinema (OSTI)

    None

    2011-04-25

    S.P.Worden, membre technique de l'U.S.délégation à Genève pour les négociations sur les armes nucléaires, est physicien, astronome, scientifique et officier de l'armée de l'air. Il parlera des technologies de défense stratégique

  19. Le LHC, un tunnel cosmique

    SciTech Connect (OSTI)

    2009-09-17

    Et si la lumière au bout du tunnel du LHC était cosmique ? En d’autres termes, qu’est-ce que le LHC peut nous apporter dans la connaissance de l’Univers ? Car la montée en énergie des accélérateurs de particules nous permet de mieux appréhender l’univers primordial, chaud et dense. Mais dans quel sens dit-on que le LHC reproduit des conditions proches du Big bang ? Quelles informations nous apporte-t-il sur le contenu de l’Univers ? La matière noire est-elle détectable au LHC ? L’énergie noire ? Pourquoi l’antimatière accumulée au CERN est-elle si rare dans l’Univers ? Et si le CERN a bâti sa réputation sur l’exploration des forces faibles et fortes qui opèrent au sein des atomes et de leurs noyaux, est-ce que le LHC peut nous apporter des informations sur la force gravitationnelle qui gouverne l’évolution cosmique ? Depuis une trentaine d’années, notre compréhension de l’univers dans ses plus grandes dimensions et l’appréhension de son comportement aux plus petites distances sont intimement liées : en quoi le LHC va-t-il tester expérimentalement cette vision unifiée ? Tout public, entrée libre / Réservations au +41 (0)22 767 76 76

  20. Le LHC, un tunnel cosmique

    ScienceCinema (OSTI)

    None

    2011-10-06

    Et si la lumière au bout du tunnel du LHC était cosmique ? En d?autres termes, qu?est-ce que le LHC peut nous apporter dans la connaissance de l?Univers ? Car la montée en énergie des accélérateurs de particules nous permet de mieux appréhender l?univers primordial, chaud et dense. Mais dans quel sens dit-on que le LHC reproduit des conditions proches du Big bang ? Quelles informations nous apporte-t-il sur le contenu de l?Univers ? La matière noire est-elle détectable au LHC ? L?énergie noire ? Pourquoi l?antimatière accumulée au CERN est-elle si rare dans l?Univers ? Et si le CERN a bâti sa réputation sur l?exploration des forces faibles et fortes qui opèrent au sein des atomes et de leurs noyaux, est-ce que le LHC peut nous apporter des informations sur la force gravitationnelle qui gouverne l?évolution cosmique ? Depuis une trentaine d?années, notre compréhension de l?univers dans ses plus grandes dimensions et l?appréhension de son comportement aux plus petites distances sont intimement liées : en quoi le LHC va-t-il tester expérimentalement cette vision unifiée ? Tout public, entrée libre / Réservations au +41 (0)22 767 76 76

  1. The Dark Energy Survey Data Management System

    SciTech Connect (OSTI)

    Mohr, Joseph J.; Barkhouse, Wayne; Beldica, Cristina; Bertin, Emmanuel; Dora Cai, Y.; Nicolaci da Costa, Luiz A.; Darnell, J.Anthony; Daues, Gregory E.; Jarvis, Michael; Gower, Michelle; Lin, Huan; /Fermilab /Rio de Janeiro Observ.

    2008-07-01

    The Dark Energy Survey (DES) collaboration will study cosmic acceleration with a 5000 deg2 griZY survey in the southern sky over 525 nights from 2011-2016. The DES data management (DESDM) system will be used to process and archive these data and the resulting science ready data products. The DESDM system consists of an integrated archive, a processing framework, an ensemble of astronomy codes and a data access framework. We are developing the DESDM system for operation in the high performance computing (HPC) environments at the National Center for Supercomputing Applications (NCSA) and Fermilab. Operating the DESDM system in an HPC environment offers both speed and flexibility. We will employ it for our regular nightly processing needs, and for more compute-intensive tasks such as large scale image coaddition campaigns, extraction of weak lensing shear from the full survey dataset, and massive seasonal reprocessing of the DES data. Data products will be available to the Collaboration and later to the public through a virtual-observatory compatible web portal. Our approach leverages investments in publicly available HPC systems, greatly reducing hardware and maintenance costs to the project, which must deploy and maintain only the storage, database platforms and orchestration and web portal nodes that are specific to DESDM. In Fall 2007, we tested the current DESDM system on both simulated and real survey data. We used TeraGrid to process 10 simulated DES nights (3TB of raw data), ingesting and calibrating approximately 250 million objects into the DES Archive database. We also used DESDM to process and calibrate over 50 nights of survey data acquired with the Mosaic2 camera. Comparison to truth tables in the case of the simulated data and internal crosschecks in the case of the real data indicate that astrometric and photometric data quality is excellent.

  2. Adaptive LES Methodology for Turbulent Flow Simulations

    SciTech Connect (OSTI)

    Oleg V. Vasilyev

    2008-06-12

    Although turbulent flows are common in the world around us, a solution to the fundamental equations that govern turbulence still eludes the scientific community. Turbulence has often been called one of the last unsolved problem in classical physics, yet it is clear that the need to accurately predict the effect of turbulent flows impacts virtually every field of science and engineering. As an example, a critical step in making modern computational tools useful in designing aircraft is to be able to accurately predict the lift, drag, and other aerodynamic characteristics in numerical simulations in a reasonable amount of time. Simulations that take months to years to complete are much less useful to the design cycle. Much work has been done toward this goal (Lee-Rausch et al. 2003, Jameson 2003) and as cost effective accurate tools for simulating turbulent flows evolve, we will all benefit from new scientific and engineering breakthroughs. The problem of simulating high Reynolds number (Re) turbulent flows of engineering and scientific interest would have been solved with the advent of Direct Numerical Simulation (DNS) techniques if unlimited computing power, memory, and time could be applied to each particular problem. Yet, given the current and near future computational resources that exist and a reasonable limit on the amount of time an engineer or scientist can wait for a result, the DNS technique will not be useful for more than 'unit' problems for the foreseeable future (Moin & Kim 1997, Jimenez & Moin 1991). The high computational cost for the DNS of three dimensional turbulent flows results from the fact that they have eddies of significant energy in a range of scales from the characteristic length scale of the flow all the way down to the Kolmogorov length scale. The actual cost of doing a three dimensional DNS scales as Re{sup 9/4} due to the large disparity in scales that need to be fully resolved. State-of-the-art DNS calculations of isotropic turbulence

  3. AGB sodium abundances in the globular cluster 47 Tucanae (NGC 104)

    SciTech Connect (OSTI)

    Johnson, Christian I.; McDonald, Iain; Zijlstra, Albert A. E-mail: iain.mcdonald-2@manchester.ac.uk; and others

    2015-02-01

    A recent analysis comparing the [Na/Fe] distributions of red giant branch (RGB) and asymptotic giant branch (AGB) stars in the Galactic globular cluster NGC 6752 found that the ratio of Na-poor to Na-rich stars changes from 30:70 on the RGB to 100:0 on the AGB. The surprising paucity of Na-rich stars on the AGB in NGC 6752 warrants additional investigations to determine if the failure of a significant fraction of stars to ascend the AGB is an attribute common to all globular clusters. Therefore, we present radial velocities, [Fe/H], and [Na/Fe] abundances for 35 AGB stars in the Galactic globular cluster 47 Tucanae (47 Tuc; NGC 104), and compare the AGB [Na/Fe] distribution with a similar RGB sample published previously. The abundances and velocities were derived from high-resolution spectra obtained with the Michigan/Magellan Fiber System and MSpec spectrograph on the MagellanClay 6.5 m telescope. We find the average heliocentric radial velocity and [Fe/H] values to be ?RV{sub helio.}? = ?18.56 km s{sup ?1} (? = 10.21 km s{sup ?1}) and ?[Fe/H]? = ?0.68 (? = 0.08), respectively, in agreement with previous literature estimates. The average [Na/Fe] abundance is 0.12 dex lower in the 47 Tuc AGB sample compared to the RGB sample, and the ratio of Na-poor to Na-rich stars is 63:37 on the AGB and 45:55 on the RGB. However, in contrast to NGC 6752, the two 47 Tuc populations have nearly identical [Na/Fe] dispersion and interquartile range values. The data presented here suggest that only a small fraction (?20%) of Na-rich stars in 47 Tuc may fail to ascend the AGB, which is a similar result to that observed in M13. Regardless of the cause for the lower average [Na/Fe] abundance in AGB stars, we find that Na-poor stars and at least some Na-rich stars in 47 Tuc evolve through the early AGB phase. The contrasting behavior of Na-rich stars in 47 Tuc and NGC 6752 suggests that the RGB [Na/Fe] abundance alone is insufficient for predicting if a star will ascend the AGB.

  4. Blue straggler star populations in globular clusters. I. Dynamical properties of blue straggler stars in NGC 3201, NGC 6218, and ? Centauri

    SciTech Connect (OSTI)

    Simunovic, Mirko; Puzia, Thomas H. E-mail: tpuzia@astro.puc.cl

    2014-02-10

    We present the first dynamical study of blue straggler stars (BSSs) in three Galactic globular clusters, NGC 3201, NGC 5139 (? Cen), and NGC 6218, based on medium-resolution spectroscopy (R ? 10, 000) obtained with the Inamori-Magellan Areal Camera and Spectrograph mounted at the 6.5 m Baade Magellan telescope. Our BSS candidate selection technique uses HST/ACS and ESO/WFI photometric data out to >4.5 r{sub c} . We use radial velocity measurements to discard non-members and achieve a success rate of ?93%, which yields a sample of 116 confirmed BSSs. Using the penalized pixel-fitting method (pPXF), we measure the vsin (i) values of the sample BSSs and find their distribution functions peaked at slow velocities with a long tail toward fast velocities in each globular cluster. About 90% of the BSS population in NGC 3201 and NGC 6218 exhibits values in the range 10-50 km s{sup 1}, while about 80% of the BSSs in ? Cen show vsin (i) values between 20 and 70 km s{sup 1}. We find that the BSSs in NGC 3201 and NGC 6218 that show vsin (i) > 50 km s{sup 1} are all found in the central cluster regions, inside a projected 2r{sub c} , of their parent clusters. We find a similar result in ? Cen for BSSs with vsin (i) > 70 km s{sup 1}, which are all, except for two, concentrated inside 2r{sub c} . In all globular clusters, we find rapidly rotating BSSs that have relatively high differential radial velocities that likely put them on hyperbolic orbits, suggestive of strong dynamical interactions in the past. Based on stellar spin-down and dynamical crossing timescales, we estimate that all the observed rapidly rotating BSSs are likely to form in their central cluster regions no longer than ?300 Myr ago and may be subsequently ejected from their host globular clusters. Using dereddened V I colors of our photometric selection, we show that blue BSSs in ? Cen with (V I){sub 0} ? 0.25 mag show a significantly increased vsin (i) dispersion compared with their red counterparts and

  5. The Carnegie-Spitzer-IMACS redshift survey of galaxy evolution since z = 1.5. I. Description and methodology

    SciTech Connect (OSTI)

    Kelson, Daniel D.; Williams, Rik J.; Dressler, Alan; McCarthy, Patrick J.; Shectman, Stephen A.; Mulchaey, John S.; Villanueva, Edward V.; Crane, Jeffrey D.; Quadri, Ryan F.

    2014-03-10

    We describe the Carnegie-Spitzer-IMACS (CSI) Survey, a wide-field, near-IR selected spectrophotometric redshift survey with the Inamori Magellan Areal Camera and Spectrograph (IMACS) on Magellan-Baade. By defining a flux-limited sample of galaxies in Spitzer Infrared Array Camera 3.6 μm imaging of SWIRE fields, the CSI Survey efficiently traces the stellar mass of average galaxies to z ∼ 1.5. This first paper provides an overview of the survey selection, observations, processing of the photometry and spectrophotometry. We also describe the processing of the data: new methods of fitting synthetic templates of spectral energy distributions are used to derive redshifts, stellar masses, emission line luminosities, and coarse information on recent star formation. Our unique methodology for analyzing low-dispersion spectra taken with multilayer prisms in IMACS, combined with panchromatic photometry from the ultraviolet to the IR, has yielded high-quality redshifts for 43,347 galaxies in our first 5.3 deg{sup 2} of the SWIRE XMM-LSS field. We use three different approaches to estimate our redshift errors and find robust agreement. Over the full range of 3.6 μm fluxes of our selection, we find typical redshift uncertainties of σ {sub z}/(1 + z) ≲ 0.015. In comparisons with previously published spectroscopic redshifts we find scatters of σ {sub z}/(1 + z) = 0.011 for galaxies at 0.7 ≤ z ≤ 0.9, and σ {sub z}/(1 + z) = 0.014 for galaxies at 0.9 ≤ z ≤ 1.2. For galaxies brighter and fainter than i = 23 mag, we find σ {sub z}/(1 + z) = 0.008 and σ {sub z}/(1 + z) = 0.022, respectively. Notably, our low-dispersion spectroscopy and analysis yields comparable redshift uncertainties and success rates for both red and blue galaxies, largely eliminating color-based systematics that can seriously bias observed dependencies of galaxy evolution on environment.

  6. Search for surviving companions in type Ia supernova remnants

    SciTech Connect (OSTI)

    Pan, Kuo-Chuan; Ricker, Paul M.; Taam, Ronald E. E-mail: pmricker@illinois.edu E-mail: taam@asiaa.sinica.edu.tw

    2014-09-01

    The nature of the progenitor systems of type Ia supernovae (SNe Ia) is still unclear. One way to distinguish between the single-degenerate scenario and double-degenerate scenario for their progenitors is to search for the surviving companions (SCs). Using a technique that couples the results from multi-dimensional hydrodynamics simulations with calculations of the structure and evolution of main-sequence- (MS-) and helium-rich SCs, the color and magnitude of MS- and helium-rich SCs are predicted as functions of time. The SC candidates in Galactic type Ia supernova remnants (Ia SNR) and nearby extragalactic Ia SNRs are discussed. We find that the maximum detectable distance of MS SCs (helium-rich SCs) is 0.6-4 Mpc (0.4-16 Mpc), if the apparent magnitude limit is 27 in the absence of extinction, suggesting that the Large and Small Magellanic Clouds and the Andromeda Galaxy are excellent environments in which to search for SCs. However, only five Ia SNRs have been searched for SCs, showing little support for the standard channels in the singe-degenerate scenario. To better understand the progenitors of SNe Ia, we encourage the search for SCs in other nearby Ia SNRs.

  7. The multiplicity of massive stars: A high angular resolution survey with the HST fine guidance sensor

    SciTech Connect (OSTI)

    Aldoretta, E. J.; Gies, D. R.; Henry, T. J.; Jao, W.-C.; Norris, R. P. E-mail: gies@chara.gsu.edu E-mail: jao@chara.gsu.edu; and others

    2015-01-01

    We present the results of an all-sky survey made with the Fine Guidance Sensor on the Hubble Space Telescope to search for angularly resolved binary systems among massive stars. The sample of 224 stars is comprised mainly of Galactic O- and B-type stars and luminous blue variables, plus a few luminous stars in the Large Magellanic Cloud. The FGS TRANS mode observations are sensitive to the detection of companions with an angular separation between 0.″01 and 1.″0 and brighter than △m=5. The FGS observations resolved 52 binary and 6 triple star systems and detected partially resolved binaries in 7 additional targets (43 of these are new detections). These numbers yield a companion detection frequency of 29% for the FGS survey. We also gathered literature results on the numbers of close spectroscopic binaries and wider astrometric binaries among the sample, and we present estimates of the frequency of multiple systems and the companion frequency for subsets of stars residing in clusters and associations, field stars, and runaway stars. These results confirm the high multiplicity fraction, especially among massive stars in clusters and associations. We show that the period distribution is approximately flat in increments of logP. We identify a number of systems of potential interest for long-term orbital determinations, and we note the importance of some of these companions for the interpretation of the radial velocities and light curves of close binaries that have third companions.

  8. SPECTRAL IDENTIFICATION OF AN ANCIENT SUPERNOVA USING LIGHT ECHOES IN THE LMC

    SciTech Connect (OSTI)

    Rest, A; Matheson, T; Blondin, S; Bergmann, M; Welch, D L; Suntzeff, N B; Smith, R C; Olsen, K; Prieto, J L; Garg, A; Challis, P; Stubbs, C; Hicken, M; Modjaz, M; Wood-Vasey, W M; Zenteno, A; Damke, G; Newman, A; Huber, M; Cook, K H; Nikolaev, S; Becker, A C; Miceli, A; Covarrubias, R; Morelli, L; Pignata, G; Clocchiatti, A; Minniti, D; Foley, R J

    2008-02-07

    We report the successful identification of the type of the supernova responsible for the supernova remnant SNR 0509-675 in the Large Magellanic Cloud (LMC) using Gemini spectra of surrounding light echoes. The ability to classify outbursts associated with centuries-old remnants provides a new window into several aspects of supernova research and is likely to be successful in providing new constraints on additional LMC supernovae as well as their historical counterparts in the Milky Way Galaxy (MWG). The combined spectrum of echo light from SNR 0509-675 shows broad emission and absorption lines consistent with a supernova (SN) spectrum. We create a spectral library consisting of 26 SNe Ia and 6 SN Ib/c that are time-integrated, dust-scattered by LMC dust, and reddened by the LMC and MWG. We fit these SN templates to the observed light echo spectrum using {chi}{sup 2} minimization as well as correlation techniques, and we find that overluminous 91T-like SNe Ia with {Delta}m{sub 15} < 0.9 match the observed spectrum best.

  9. Extraordinary luminous soft X-ray transient MAXI J0158744 as an ignition of a nova on a very massive O-Ne white dwarf

    SciTech Connect (OSTI)

    Morii, M.; Serino, M.; Mihara, T.; Sugizaki, M.; Tomida, H.; Kimura, M.; Nakahira, S.; Suwa, F.; Negoro, H.; Kennea, J. A.; Pritchard, T.; Page, K. L.; Osborne, J. P.; Curran, P. A.; Walter, F. M.; Kuin, N. P. M.; Hiroi, K.; Usui, R.; Kawai, N.; Gehrels, N.; and others

    2013-12-20

    We present the observation of an extraordinary luminous soft X-ray transient, MAXI J0158744, by the Monitor of All-sky X-ray Image (MAXI) on 2011 November 11. This transient is characterized by a soft X-ray spectrum, a short duration (1.3 10{sup 3} s < ?T{sub d} < 1.10 10{sup 4} s), a rapid rise (<5.5 10{sup 3} s), and a huge peak luminosity of 2 10{sup 40} erg s{sup 1} in 0.7-7.0 keV band. With Swift observations and optical spectroscopy from the Small and Moderate Aperture Research Telescope System, we confirmed that the transient is a nova explosion, on a white dwarf in a binary with a Be star, located near the Small Magellanic Cloud. An early turn-on of the super-soft X-ray source (SSS) phase (<0.44 days), the short SSS phase duration of about one month, and a 0.92 keV neon emission line found in the third MAXI scan, 1296 s after the first detection, suggest that the explosion involves a small amount of ejecta and is produced on an unusually massive O-Ne white dwarf close to, or possibly over, the Chandrasekhar limit. We propose that the huge luminosity detected with MAXI was due to the fireball phase, a direct manifestation of the ignition of the thermonuclear runaway process in a nova explosion.

  10. MACHO (MAssive Compact Halo Objects) Data

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    The primary aim of the MACHO Project is to test the hypothesis that a significant fraction of the dark matter in the halo of the Milky Way is made up of objects like brown dwarfs or planets: these objects have come to be known as MACHOs, for MAssive Compact Halo Objects. The signature of these objects is the occasional amplification of the light from extragalactic stars by the gravitational lens effect. The amplification can be large, but events are extremely rare: it is necessary to monitor photometrically several million stars for a period of years in order to obtain a useful detection rate. For this purpose MACHO has a two channel system that employs eight CCDs, mounted on the 50 inch telescope at Mt. Stromlo. The high data rate (several GBytes per night) is accommodated by custom electronics and on-line data reduction. The Project has taken more than 27,000 images with this system since June 1992. Analysis of a subset of these data has yielded databases containing light curves in two colors for 8 million stars in the LMC and 10 million in the bulge of the Milky Way. A search for microlensing has turned up four candidates toward the Large Magellanic Cloud and 45 toward the Galactic Bulge. The web page for data provides links to MACHO Project data portals and various specialized interfaces for viewing or searching the data. (Specialized Interface)

  11. A STUDY OF GRAVITATIONAL LENS CHROMATICITY WITH THE HUBBLE SPACE TELESCOPE

    SciTech Connect (OSTI)

    Munoz, J. A.; Mosquera, A. M.; Mediavilla, E.; Kochanek, C. S.; Falco, E. E.

    2011-12-01

    We report Hubble Space Telescope observations of six gravitational lenses with the Advanced Camera for Surveys. We measured the flux ratios between the lensed images in seven filters from 8140 #Angstrom# to 2200 #Angstrom#. In three of the systems, HE0512-3329, B1600+434, and H1413+117, we were able to construct UV extinction curves partially overlapping the 2175 #Angstrom# feature and characterize the properties of the dust relative to the Galaxy and the Magellanic Clouds. In HE1104-1804, we detect chromatic microlensing and use it to study the physical properties of the quasar accretion disk. For a Gaussian model of the disk exp (- r{sup 2}/2r{sup 2}{sub s}), scaling with wavelength as r{sub s} {proportional_to}{lambda}{sup p}, we estimate r{sub s} ({lambda}3363) = 4{sup +4}{sub -2} (7 {+-} 4) light days and p = 1.1 {+-} 0.6 (1.0 {+-} 0.6) for a logarithmic (linear) prior on r{sub s} . The remaining two systems, FBQ0951+2635 and SBS1520+530, yielded no useful estimates of extinction or chromatic microlensing.

  12. THE CEPHEID PERIOD-LUMINOSITY RELATION (THE LEAVITT LAW) AT MID-INFRARED WAVELENGTHS. IV. CEPHEIDS IN IC 1613

    SciTech Connect (OSTI)

    Freedman, Wendy L.; Rigby, Jane; Madore, Barry F.; Persson, S. E.; Sturch, Laura; Mager, Violet E-mail: jrigby@ociw.edu E-mail: persson@ociw.edu E-mail: vmager@ociw.edu

    2009-04-20

    We present mid-infrared period-luminosity relations for Cepheids in the Local Group galaxy IC 1613. Using archival Infrared Array Camera (IRAC) imaging data from Spitzer we were able to measure single-epoch magnitudes for five, 7-50 days, Cepheids at 3.6 and 4.5 {mu}m. When fit to the calibrating relations, measured for the Large Magellanic Cloud Cepheids, the data give apparent distance moduli of 24.29 {+-} 0.07 and 24.28 {+-} 0.07 at 3.6 and 4.5 {mu}m, respectively. A multiwavelength fit to previously published BVRIJHK apparent moduli and the two IRAC moduli gives a true distance modulus of 24.27 {+-} 0.02 mag with E(B - V) = 0.08 mag, and a corresponding metric distance of 715 kpc. Given that these results are based on single-phase observations derived from exposures having total integration times of only 1000 s pixel{sup -1}, we suggest that Cepheids out to about 2 Mpc are accessible to Spitzer with modest integration times during its warm mission. We identify the main limiting factor to this method to be crowding/contamination induced by the ubiquitous population of infrared-bright asymptotic giant branch stars.

  13. Searching for debris disks around seven radio pulsars

    SciTech Connect (OSTI)

    Wang, Zhongxiang; Wang, Xuebing; Ng, C.-Y.; Li, Aigen; Kaplan, David L.

    2014-10-01

    We report on our searches for debris disks around seven relatively nearby radio pulsars, which are isolated sources that were carefully selected as targets on the basis of our deep K{sub s} -band imaging survey. The K{sub s} images obtained with the 6.5 m Baade Magellan Telescope at Las Campanas Observatory are analyzed together with the Spitzer/IRAC images at 4.5 and 8.0 μm and the WISE images at 3.4, 4.6, 12, and 22 μm. No infrared counterparts of these pulsars are found, with flux upper limits of ∼μJy at near-infrared (λ < 10 μm) and ∼10-1000 μJy at mid-infrared wavelengths (λ > 10 μm). The results of this search are discussed in terms of the efficiency of converting the pulsar spin-down energy to thermal energy and X-ray heating of debris disks, with a comparison made of the two magnetars 4U 0142+61 and 1E 2259+586, which are suggested to harbor a debris disk.

  14. CONFIRMATION OF ONE OF THE COLDEST KNOWN BROWN DWARFS

    SciTech Connect (OSTI)

    Luhman, K. L.; Bochanski, J. J.; Burgasser, A. J.; Labbe, I.; Monson, A. J.; Persson, S. E.; Saumon, D.; Marley, M. S.

    2012-01-10

    Using two epochs of 4.5 {mu}m images from the Infrared Array Camera (IRAC) on board the Spitzer Space Telescope, we recently identified a common proper motion companion to the white dwarf WD 0806-661 that is a candidate for the coldest known brown dwarf. To verify its cool nature, we have obtained images of this object at 3.6 {mu}m with IRAC, at J with the High Acuity Wide-field K-band Imager (HAWK-I) on the Very Large Telescope, and in a filter covering the red half of J with FourStar on Magellan. WD 0806-661 B is detected by IRAC but not HAWK-I or FourStar. From these data we measure colors of [3.6] - [4.5] = 2.77 {+-} 0.16 and J - [4.5] > 7.0 (S/N < 3). Based on these colors and its absolute magnitudes, WD 0806-661 B is the coldest companion directly imaged outside of the solar system and is a contender for the coldest known brown dwarf with the Y dwarf WISEP J1828+2650. It is unclear which of these two objects is colder given the available data. A comparison of its absolute magnitude at 4.5 {mu}m to the predictions of theoretical spectra and evolutionary models suggests that WD 0806-661 B has T{sub eff} = 300-345 K.

  15. CLOSE COMPANIONS TO YOUNG STARS. I. A LARGE SPECTROSCOPIC SURVEY IN CHAMAELEON I AND TAURUS-AURIGA

    SciTech Connect (OSTI)

    Nguyen, Duy Cuong; Brandeker, Alexis; Van Kerkwijk, Marten H.; Jayawardhana, Ray E-mail: mhvk@astro.utoronto.ca E-mail: dcnguyen@pas.rochester.edu E-mail: alexis@astro.su.se

    2012-02-01

    We present the results of a multiplicity survey of 212 T Tauri stars in the Chamaeleon I and Taurus-Auriga star-forming regions, based on high-resolution spectra from the Magellan Clay 6.5 m telescope. From these data, we achieved a typical radial velocity (RV) precision of {approx}80 m s{sup -1} with slower rotators yielding better precision, in general. For 174 of these stars, we obtained multi-epoch data with sufficient time baselines to identify binaries based on RV variations. We identified eight close binaries and four close triples, of which three and two, respectively, are new discoveries. The spectroscopic multiplicity fractions we find for Chamaeleon I (7%) and Taurus-Auriga (6%) are similar to each other, and to the results of field star surveys in the same mass and period regime. However, unlike the results from imaging surveys, the frequency of systems with close companions in our sample is not seen to depend on primary mass. Additionally, we do not find a strong correlation between accretion and close multiplicity. This implies that close companions are not likely the main source of the accretion shut down observed in weak-lined T Tauri stars. Our results also suggest that sufficient RV precision can be achieved for at least a subset of slowly rotating young stars to search for hot Jupiter planets.

  16. DISRUPTION OF STAR CLUSTERS IN THE INTERACTING ANTENNAE GALAXIES

    SciTech Connect (OSTI)

    Karl, Simon J.; Naab, Thorsten; Fall, S. Michael E-mail: naab@mpa-garching.mpg.de

    2011-06-10

    We re-examine the age distribution of star clusters in the Antennae in the context of N-body+hydrodynamical simulations of these interacting galaxies. All of the simulations that account for the observed morphology and other properties of the Antennae have star formation rates that vary relatively slowly with time, by factors of only 1.3-2.5 in the past 10{sup 8} yr. In contrast, the observed age distribution of the clusters declines approximately as a power law, dN/d{tau}{proportional_to}{tau}{sup {gamma}} with {gamma} = -1.0, for ages 10{sup 6} yr {approx}< {tau} {approx}< 10{sup 9} yr. These two facts can only be reconciled if the clusters are disrupted progressively for at least {approx}10{sup 8} yr and possibly {approx}10{sup 9} yr. When we combine the simulated formation rates with a power-law model, f{sub surv}{proportional_to}{tau}{sup {delta}}, for the fraction of clusters that survive to each age {tau}, we match the observed age distribution with exponents in the range -0.9 {approx}< {delta} {approx}< -0.6 (with a slightly different {delta} for each simulation). The similarity between {delta} and {gamma} indicates that dN/d{tau} is shaped mainly by the disruption of clusters rather than variations in their formation rate. Thus, the situation in the interacting Antennae resembles that in relatively quiescent galaxies such as the Milky Way and the Magellanic Clouds.

  17. GRAVITATIONAL CONUNDRUM? DYNAMICAL MASS SEGREGATION VERSUS DISRUPTION OF BINARY STARS IN DENSE STELLAR SYSTEMS

    SciTech Connect (OSTI)

    De Grijs, Richard; Li, Chengyuan; Zheng, Yong; Kouwenhoven, M. B. N.; Deng, Licai; Hu, Yi; Wicker, James E.

    2013-03-01

    Upon their formation, dynamically cool (collapsing) star clusters will, within only a few million years, achieve stellar mass segregation for stars down to a few solar masses, simply because of gravitational two-body encounters. Since binary systems are, on average, more massive than single stars, one would expect them to also rapidly mass segregate dynamically. Contrary to these expectations and based on high-resolution Hubble Space Telescope observations, we show that the compact, 15-30 Myr old Large Magellanic Cloud cluster NGC 1818 exhibits tantalizing hints at the {approx}> 2{sigma} level of significance (>3{sigma} if we assume a power-law secondary-to-primary mass-ratio distribution) of an increasing fraction of F-star binary systems (with combined masses of 1.3-1.6 M {sub Sun }) with increasing distance from the cluster center, specifically between the inner 10''-20'' (approximately equivalent to the cluster's core and half-mass radii) and the outer 60''-80''. If confirmed, then this will offer support for the theoretically predicted but thus far unobserved dynamical disruption processes of the significant population of 'soft' binary systems-with relatively low binding energies compared to the kinetic energy of their stellar members-in star clusters, which we have access to here by virtue of the cluster's unique combination of youth and high stellar density.

  18. THE 300 km s{sup -1} STELLAR STREAM NEAR SEGUE 1: INSIGHTS FROM HIGH-RESOLUTION SPECTROSCOPY OF ITS BRIGHTEST STAR

    SciTech Connect (OSTI)

    Frebel, Anna; Casey, Andrew R.; Lunnan, Ragnhild; Norris, John E.; Wyse, Rosemary F. G.; Gilmore, Gerard

    2013-07-01

    We present a chemical abundance analysis of 300S-1, the brightest likely member star of the 300 km s{sup -1} stream near the faint satellite galaxy Segue 1. From a high-resolution Magellan/MIKE spectrum, we determine a metallicity of [Fe/H] = -1.46 {+-} 0.05 {+-} 0.23 (random and systematic uncertainties) for star 300S-1, and find an abundance pattern similar to typical halo stars at this metallicity. Comparing our stellar parameters to theoretical isochrones, we estimate a distance of 18 {+-} 7 kpc. Both the metallicity and distance estimates are in good agreement with what can be inferred from comparing the Sloan Digital Sky Survey photometric data of the stream stars to globular cluster sequences. While several other structures overlap with the stream in this part of the sky, the combination of kinematic, chemical, and distance information makes it unlikely that these stars are associated with either the Segue 1 galaxy, the Sagittarius Stream, or the Orphan Stream. Streams with halo-like abundance signatures, such as the 300 km s{sup -1} stream, present another observational piece for understanding the accretion history of the Galactic halo.

  19. SEMIREGULAR VARIABLES WITH PERIODS LYING BETWEEN THE PERIOD-LUMINOSITY SEQUENCES C', C, AND D

    SciTech Connect (OSTI)

    Soszynski, I.; Wood, P. R. E-mail: wood@mso.anu.edu.au

    2013-02-15

    We analyze the distribution of semiregular variables and Mira stars in the period-luminosity plane. Our sample consists of 6169 oxygen-rich long-period variables in the Large Magellanic Cloud included in the OGLE-III Catalog of Variable Stars. There are many stars with periods that lie between the well-known sequences C and C'. Most of these stars are multi-periodic and the period ratios suggest that these stars oscillate in the same mode as the sequence C stars. Models suggest that this mode is the fundamental radial pulsation mode. The stars with primary periods between sequences C and C' preferentially lie on an additional sequence (named F), and a large fraction of these stars also have long secondary periods (LSPs) that lie between sequences C and D. There are also a small number of stars with primary periods lying between sequences C and D. The origin of this long-period variability is unknown, as is the cause of sequence D variability. In addition, the origin of sequence F is unknown but we speculate that sequence F variability may be excited by the same phenomenon that causes the LSPs.

  20. THE DISTANCE MEASUREMENT OF NGC1313 WITH CEPHEIDS

    SciTech Connect (OSTI)

    Qing, Gao; Wang, Wei; Liu, Ji-Feng; Yoachim, Peter

    2015-01-20

    We present the detection of Cepheids in the barred spiral galaxy NGC 1313, using the Wide Field and Planetary Camera 2 on the Hubble Space Telescope. Twenty B(F450W) and V(F555W) epochs of observations spanning over three weeks were obtained, on which the profile-fitting photometry of all stars in the monitored field was performed using the package HSTphot. A sample of 26 variable stars have been identified to be Cepheids, with periods between 3 and 14 days. Based on the derived period-luminosity relations in B- and V-bands, we obtain an extinction-corrected distance modulus of ?{sub NGC} {sub 1313} = 28.32 0.08 (random) 0.06 (systematic), employing the Large Magellanic Cloud as the distance zero point calibrator. The above moduli correspond to a distance of 4.61 0.17 (random) 0.13 (systematic) Mpc, consistent with previous measurements reported in the literature within uncertainties. In addition, the reddening to NGC 1313 is found to be small.

  1. South America. The boom is almost everywhere

    SciTech Connect (OSTI)

    Not Available

    1981-08-15

    In South America, drilling activity is increasing rapidly. Three-dimensional seismic is being used offshore Brazil. Argentina has increased its processing capability by several companies. Venezuela has increased its survey mileage. Hundreds of post holes are being drilled in the Orinoco oil belt. Deep, difficult holes are being drilled in N. Argentina and N.E. Columbia. Offshore Chile, Enap is drilling high angle deviated holes in the Strait of Magellan. Belco is continuing its slant hole drilling campaign off Peru. In production, Venezuela has a major steam flood project and 2 large steam soak projects underway. Occidental is increasing its waterflood project in Talara, Peru, to 600,000 bbl of water/day. There are a number of projects underway in Argentina and Petrobras is continuing its experiments with steam and fire-flooding. Brazil has reached an all-time production high. Of the major producing countries in South America. Only Trinidad is declining in drilling and oil production. Ecuador is still attempting to develop Amistad field in the Gulf of Guayaquil.

  2. THE CoRoT DISCOVERY OF A UNIQUE TRIPLE-MODE CEPHEID IN THE GALAXY

    SciTech Connect (OSTI)

    Poretti, E.; Baglin, A.; Weiss, W. W.

    2014-11-10

    The exploitation of the CoRoT treasure of stars observed in the exoplanetary field allowed the detection of a unusual triple-mode Cepheid in the Milky Way, CoRoT 0223989566. The two modes with the largest amplitudes and a period ratio of 0.80 are identified with the first (P {sub 1} = 1.29 days) and second (P {sub 2} = 1.03 days) radial overtones. The third period, which has the smallest amplitude but is able to produce combination terms with the other two, is the longest one (P {sub 3} = 1.89 days). The ratio of 0.68 between the first-overtone period and the third period is the unusual feature. Its identification with the fundamental radial or a nonradial mode is discussed with respect to similar cases in the Magellanic Clouds. In both cases, the period triplet and the respective ratios make the star unique in our Galaxy. The distance derived from the period-luminosity relation and the galactic coordinates put CoRoT 0223989566 in the metal-rich environment of the ''outer arm'' of the Milky Way.

  3. THE SIZE DISTRIBUTION OF THE NEPTUNE TROJANS AND THE MISSING INTERMEDIATE-SIZED PLANETESIMALS

    SciTech Connect (OSTI)

    Sheppard, Scott S.; Trujillo, Chadwick A.

    2010-11-10

    We present an ultra-deep survey for Neptune Trojans using the Subaru 8.2 m and Magellan 6.5 m telescopes. The survey reached a 50% detection efficiency in the R band at m{sub R} = 25.7 mag and covered 49 deg{sup 2} of sky. m{sub R} = 25.7 mag corresponds to Neptune Trojans that are about 16 km in radius (assuming an albedo of 0.05). A paucity of smaller Neptune Trojans (radii < 45 km) compared with larger ones was found. The brightest Neptune Trojans appear to follow a steep power-law slope (q = 5 {+-} 1) similar to the brightest objects in the other known stable reservoirs such as the Kuiper Belt, Jupiter Trojans, and main belt asteroids. We find a roll-over for the Neptune Trojans that occurs around a radius of r = 45 {+-} 10 km (m{sub R} = 23.5 {+-} 0.3), which is also very similar to the other stable reservoirs. All the observed stable regions in the solar system show evidence for Missing Intermediate-Sized Planetesimals (MISPs). This indicates a primordial and not collisional origin, which suggests that planetesimal formation proceeded directly from small to large objects. The scarcity of intermediate- and smaller-sized Neptune Trojans may limit them as being a strong source for the short period comets.

  4. SIX HIGH-PRECISION TRANSITS OF OGLE-TR-113b

    SciTech Connect (OSTI)

    Adams, E. R.; Elliot, J. L.; Seager, S.; Lopez-Morales, M.; Osip, D. J.

    2010-10-01

    We present six new transits of the hot Jupiter OGLE-TR-113b observed with MagIC on the Magellan Telescopes between 2007 January and 2009 May. We update the system parameters and revise the planetary radius to R{sub p} = 1.084 {+-} 0.029R{sub J} , where the error is dominated by stellar radius uncertainties. The new transit midtimes reveal no transit timing variations from a constant ephemeris of greater than 13 {+-} 28 s over two years, placing an upper limit of 1-2 M{sub +} on the mass of any perturber in a 1:2 or 2:1 mean-motion resonance with OGLE-TR-113b. Combining the new transit epochs with five epochs published between 2002 and 2006, we find hints that the orbital period of the planet may not be constant, with the best fit indicating a decrease of P-dot =-60{+-}15 ms yr{sup -1}. If real, this change in period could result from either a long-period (more than eight years) timing variation due to a massive external perturber or more intriguingly from the orbital decay of the planet. The detection of a changing period is still tentative and requires additional observations, but if confirmed it would enable direct tests of tidal stability and dynamical models of close-in planets.

  5. CHEMICAL ABUNDANCE EVIDENCE OF ENDURING HIGH STAR FORMATION RATES IN AN EARLY-TYPE GALAXY: HIGH [Ca/Fe] IN NGC 5128 GLOBULAR CLUSTERS

    SciTech Connect (OSTI)

    Colucci, Janet E.; Duran, Maria Fernanda; Bernstein, Rebecca A.

    2013-08-20

    We present [Fe/H], ages, and Ca abundances for an initial sample of 10 globular clusters in NGC 5128 obtained from high-resolution, high signal-to-noise ratio echelle spectra of their integrated light. All abundances and ages are obtained using our original technique for high-resolution integrated light abundance analysis of globular clusters. The clusters have a range in [Fe/H] between -1.6 and -0.2. In this sample, the average [Ca/Fe] for clusters with [Fe/H] <-0.4 is +0.37 {+-} 0.07, while the average [Ca/Fe] in our Milky Way (MW) and M31 GC samples is +0.29 {+-} 0.09 and +0.24 {+-} 0.10, respectively. This may imply a more rapid chemical enrichment history for NGC 5128 than for either the MW or M31. This sample provides the first quantitative picture of the chemical history of NGC 5128 that is directly comparable to what is available for the MW. Data presented here were obtained with the MIKE echelle spectrograph on the Magellan Clay Telescope.

  6. A new Cepheid distance measurement and method for NGC 6822

    SciTech Connect (OSTI)

    Rich, Jeffrey A.; Persson, S. E.; Freedman, Wendy L.; Madore, Barry F.; Monson, Andrew J.; Scowcroft, Victoria; Seibert, Mark

    2014-10-20

    We present a revised distance to the nearby galaxy NGC 6822 using a new multi-band fit to both previously published and new optical, near-, and mid-infrared data for Cepheid variables. The new data presented in this study include multi-epoch observations obtained in 3.6 μm and 4.5 μm with the Spitzer Space Telescope taken for the Carnegie Hubble Program. We also present new observations in J, H, and K{sub s} with FourStar on the Magellan Baade Telescope at Las Campanas Observatory. We determine mean magnitudes and present new period-luminosity relations in V, I, J, H, K{sub s} , Infrared Array Camera 3.6 μm, and 4.5 μm. In addition to using the multi-band distance moduli to calculate extinction and a true distance, we present a new method for determining an extinction-corrected distance modulus from multi-band data with varying sample sizes. We combine the distance moduli and extinction for individual stars to determine E(B – V) = 0.35 ± 0.04 and a true distance modulus μ {sub o} = 23.38 ± 0.02{sub stat} ± 0.04{sub sys}.

  7. Neutron-capture nucleosynthesis in the first stars

    SciTech Connect (OSTI)

    Roederer, Ian U.; Preston, George W.; Thompson, Ian B.; Shectman, Stephen A.; Sneden, Christopher

    2014-04-01

    Recent studies suggest that metal-poor stars enhanced in carbon but containing low levels of neutron-capture elements may have been among the first to incorporate the nucleosynthesis products of the first generation of stars. We have observed 16 stars with enhanced carbon or nitrogen using the MIKE Spectrograph on the Magellan Telescopes at Las Campanas Observatory and the Tull Spectrograph on the Smith Telescope at McDonald Observatory. We present radial velocities, stellar parameters, and detailed abundance patterns for these stars. Strontium, yttrium, zirconium, barium, europium, ytterbium, and other heavy elements are detected. In four stars, these heavy elements appear to have originated in some form of r-process nucleosynthesis. In one star, a partial s-process origin is possible. The origin of the heavy elements in the rest of the sample cannot be determined unambiguously. The presence of elements heavier than the iron group offers further evidence that zero-metallicity rapidly rotating massive stars and pair instability supernovae did not contribute substantial amounts of neutron-capture elements to the regions where the stars in our sample formed. If the carbon- or nitrogen-enhanced metal-poor stars with low levels of neutron-capture elements were enriched by products of zero-metallicity supernovae only, then the presence of these heavy elements indicates that at least one form of neutron-capture reaction operated in some of the first stars.

  8. The diffuse source at the center of LMC SNR 050967.5 is a background galaxy at z = 0.031

    SciTech Connect (OSTI)

    Pagnotta, Ashley [Department of Astrophysics, American Museum of Natural History, New York, NY 10024 (United States); Walker, Emma S. [Department of Physics, Yale University, New Haven, CT 06520 (United States); Schaefer, Bradley E., E-mail: pagnotta@amnh.org [Department of Physics and Astronomy, Louisiana State University, Baton Rouge, LA 70803 (United States)

    2014-06-20

    Type Ia supernovae (SNe Ia) are well-known for their use in the measurement of cosmological distances, but our continuing lack of concrete knowledge about their progenitor stars is both a matter of debate and a source of systematic error. In our attempts to answer this question, we presented unambiguous evidence that LMC SNR 050967.5, the remnant of an SN Ia that exploded in the Large Magellanic Cloud 400 50 yr ago, did not have any point sources (stars) near the site of the original supernova explosion, from which we concluded that this particular supernova must have had a progenitor system consisting of two white dwarfs. There is, however, evidence of nebulosity near the center of the remnant, which could have been left over detritus from the less massive WD, or could have been a background galaxy unrelated to the supernova explosion. We obtained long-slit spectra of the central nebulous region using GMOS on Gemini South to determine which of these two possibilities is correct. The spectra show H? emission at a redshift of z = 0.031, which implies that the nebulosity in the center of LMC SNR 050967.5 is a background galaxy, unrelated to the supernova.

  9. The HD 5980 multiple system: Masses and evolutionary status

    SciTech Connect (OSTI)

    Koenigsberger, Gloria [Instituto de Ciencias Fsicas, Universidad Nacional Autnoma de Mxico, Ave. Universidad S/N, Cuernavaca, Morelos 62210 (Mexico); Morrell, Nidia [Las Campanas Observatory, The Carnegie Observatories, Colina El Pino s/n, Casillas 601, La Serena (Chile); Hillier, D. John [Department of Physics and Astronomy, and Pittsburgh Particle Physics, Astrophysics and Cosmology Center (PITT PACC), 3941 O'Hara Street, University of Pittsburgh, Pittsburgh, PA 15260 (United States); Gamen, Roberto [Facultad de Ciencias Astronmicas y Geofsicas, Universidad Nacional de La Plata, and Instituto de Astrofsica de La Plata (CCT La Plata-CONICET), Paseo del Bosque S/N, B1900FWA La Plata (Argentina); Schneider, Fabian R. N.; Gonzlez-Jimnez, Nicols; Langer, Norbert [Argelander-Institut fr Astronomie, Auf dem Hgel 71, D-53121 Bonn (Germany); Barb, Rodolfo, E-mail: gloria@astro.unam.mx, E-mail: nmorrell@lco.edu, E-mail: hillier@pitt.edu, E-mail: rgamen@fcaglp.unlp.edu.ar, E-mail: fschneid@astro.uni-bonn.de, E-mail: ngonzalez@astro.uni-bonn.de, E-mail: nlanger@astro.uni-bonn.de, E-mail: rbarba@dfuls.cl [Departamento de Fsica, Av. Juan Cisternas 1200 Norte, Universidad de la Serena, La Serena (Chile)

    2014-10-01

    New spectroscopic observations of the LBV/WR multiple system HD 5980 in the Small Magellanic Cloud are used to address the question of the masses and evolutionary status of the two very luminous stars in the 19.3 day eclipsing binary system. Two distinct components of the N V 4944 line are detected in emission and their radial velocity variations are used to derive masses of 61 and 66 M {sub ?}, under the assumption that binary interaction effects on this atomic transition are negligible. We propose that this binary system is the product of quasi-chemically homogeneous evolution with little or no mass transfer. Thus, both of these binary stars may be candidates for gamma-ray burst progenitors or even pair instability supernovae. Analysis of the photospheric absorption lines belonging to the third-light object in the system confirm that it consists of an O-type star in a 96.56 day eccentric orbit (e = 0.82) around an unseen companion. The 5:1 period ratio and high eccentricities of the two binaries suggest that they may constitute a hierarchical quadruple system.

  10. The mass dependence of dwarf satellite galaxy quenching

    SciTech Connect (OSTI)

    Slater, Colin T.; Bell, Eric F. E-mail: ericbell@umich.edu

    2014-09-10

    We combine observations of the Local Group with data from the NASA-Sloan Atlas to show the variation in the quenched fraction of satellite galaxies from low-mass dwarf spheroidals and dwarf irregulars to more massive dwarfs similar to the Magellanic Clouds. While almost all of the low-mass (M {sub *} ≲ 10{sup 7} M {sub ☉}) dwarfs are quenched, at higher masses the quenched fraction decreases to approximately 40%-50%. This change in the quenched fraction is large and suggests a sudden change in the effectiveness of quenching that correlates with satellite mass. We combine this observation with models of satellite infall and ram pressure stripping to show that the low-mass satellites must quench within 1-2 Gyr of pericenter passage to maintain a high quenched fraction, but that many more massive dwarfs must continue to form stars today even though they likely fell into their host >5 Gyr ago. We also characterize how the susceptibility of dwarfs to ram pressure must vary as a function of mass if it is to account for the change in quenched fractions. Though neither model predicts the quenching effectiveness a priori, this modeling illustrates the physical requirements that the observed quenched fractions place on possible quenching mechanisms.

  11. EIGHT HUNDRED NEW CANDIDATES FOR GLOBULAR CLUSTERS IN NGC 5128 (Centaurus A)

    SciTech Connect (OSTI)

    Harris, Gretchen L. H.; Johnston, Kyle; Kazemzadeh, Farnoud; Gomez, Matias; Harris, William E.; Kerzendorf, Wolfgang; Geisler, Doug; Woodley, Kristin A. E-mail: kyjohnston@rim.com E-mail: matiasgomez@unab.cl E-mail: wkerzend@mso.anu.edu.au E-mail: kwoodley@phas.ubc.ca

    2012-04-15

    We have used new wide-field imaging with the Magellan IMACS camera to search for globular cluster (GC) candidates around NGC 5128, the nearest giant E galaxy. The imaging data are in the B and R broadband filters and cover a 1.55 deg{sup 2} field centered on the galaxy, corresponding to an area about 90 Multiplication-Sign 90 kpc{sup 2} at the distance of NGC 5128. All the fields were taken under exceptionally high-quality seeing conditions (FWHM = 0.''4-0.''5 in R). Using this material we are able, for the first time in the literature, to construct a homogeneous list of GC candidates covering a wide span of the NGC 5128 halo and unusually free of field contaminants (foreground stars and faint background galaxies). Selecting the measured objects by color, magnitude, ellipticity, and profile size gives us a final catalog of 833 new high-quality GC candidates brighter than R = 21 (0.8 mag fainter than the standard GC luminosity function turnover point). The measured positions have better than 0.''2 precision in both coordinates. This list can be used as the basis for spectroscopic follow-up, leading to a more comprehensive kinematic and dynamic study of the halo.

  12. Comparing Galactic Center MSSM dark matter solutions to the Reticulum II gamma-ray data

    SciTech Connect (OSTI)

    Achterberg, Abraham; Beekveld, Melissa van; Beenakker, Wim; Caron, Sascha; Hendriks, Luc

    2015-12-04

    Observations with the Fermi Large Area Telescope (LAT) indicate a possible small photon signal originating from the dwarf galaxy Reticulum II that exceeds the expected background between 2 GeV and 10 GeV. We have investigated two specific scenarios for annihilating WIMP dark matter within the phenomenological Minimal Supersymmetric Standard Model (pMSSM) framework as a possible source for these photons. We find that the same parameter ranges in pMSSM as reported by an earlier paper to be consistent with the Galactic Center excess, are also consistent with the excess observed in Reticulum II, resulting in a J-factor of log{sub 10} (J(α{sub int}=0.5{sup ∘}))≃(20.3−20.5){sub −0.3}{sup +0.2} GeV{sup 2}cm{sup −5}. This J-factor is consistent with log{sub 10} (J(α{sub int}=0.5{sup ∘}))=19.6{sub −0.7}{sup +1.0} GeV{sup 2}cm{sup −5}, which was derived using an optimized spherical Jeans analysis of kinematic data obtained from the Michigan/Magellan Fiber System (M2FS)

  13. TWO PLANETARY COMPANIONS AROUND THE K7 DWARF GJ 221: A HOT SUPER-EARTH AND A CANDIDATE IN THE SUB-SATURN DESERT RANGE

    SciTech Connect (OSTI)

    Arriagada, Pamela; Minniti, Dante; Anglada-Escude, Guillem; Butler, R. Paul; Crane, Jeffrey D.; Shectman, Stephen A.; Thompson, Ian; Wende, Sebastian

    2013-07-01

    We report two low-mass companions orbiting the nearby K7 dwarf GJ 221 that have emerged from reanalyzing 4.4 yr of publicly available HARPS spectra complemented with 2 years of high-precision Doppler measurements with Magellan/PFS. The HARPS measurements alone contain the clear signal of a low-mass companion with a period of 125 days and a minimum mass of 53.2 M{sub Circled-Plus} (GJ 221b), falling in a mass range where very few planet candidates have been found (sub-Saturn desert). The addition of 17 PFS observations allows the confident detection of a second low-mass companion (6.5 M{sub Circled-Plus }) in a hot orbit (3.87 day period, GJ 221c). Spectroscopic and photometric calibrations suggest that GJ 221 is slightly depleted ([Fe/H] {approx} -0.1) compared to the Sun, so the presence of two low-mass companions in the system confirms the trend that slightly reduced stellar metallicity does not prevent the formation of planets in the super-Earth to sub-Saturn mass regime.

  14. The VMC survey. XI. Radial stellar population gradients in the galactic globular cluster 47 Tucanae

    SciTech Connect (OSTI)

    Li, Chengyuan; De Grijs, Richard; Deng, Licai; Rubele, Stefano; Girardi, Leo; Gullieuszik, Marco; Wang, Chuchu; Bekki, Kenji; For, Bi-Qing; Cioni, Maria-Rosa L.; Clementini, Gisella; Emerson, Jim; Groenewegen, Martin A. T.; Guandalini, Roald; Marconi, Marcella; Ripepi, Vincenzo; Piatti, Andrs E.; Van Loon, Jacco Th. E-mail: grijs@pku.edu.cn

    2014-07-20

    We present a deep near-infrared color-magnitude diagram of the Galactic globular cluster 47 Tucanae, obtained with the Visible and Infrared Survey Telescope for Astronomy (VISTA) as part of the VISTA near-infrared Y, J, K{sub s} survey of the Magellanic System (VMC). The cluster stars comprising both the subgiant and red giant branches exhibit apparent, continuous variations in color-magnitude space as a function of radius. Subgiant branch stars at larger radii are systematically brighter than their counterparts closer to the cluster core; similarly, red-giant-branch stars in the cluster's periphery are bluer than their more centrally located cousins. The observations can very well be described by adopting an age spread of ?0.5 Gyr as well as radial gradients in both the cluster's helium abundance (Y) and metallicity (Z), which change gradually from (Y = 0.28, Z = 0.005) in the cluster core to (Y = 0.25, Z = 0.003) in its periphery. We conclude that the cluster's inner regions host a significant fraction of second-generation stars, which decreases with increasing radius; the stellar population in the 47 Tuc periphery is well approximated by a simple stellar population.

  15. SPECTRAL ENERGY DISTRIBUTIONS OF TYPE 1 ACTIVE GALACTIC NUCLEI IN THE COSMOS SURVEY. I. THE XMM-COSMOS SAMPLE

    SciTech Connect (OSTI)

    Elvis, M.; Hao, H.; Civano, F.; Brusa, M.; Salvato, M.; Bongiorno, A.; Cappelluti, N.; Capak, P.; Zamorani, G.; Comastri, A.; Gilli, R.; Jahnke, K.; Lusso, E.; Cisternas, M.; Mainieri, V.; Trump, J. R.; Ho, L. C.; Aussel, H.; Frayer, D.; Hasinger, G. E-mail: hhao@cfa.harvard.edu; and others

    2012-11-01

    The 'Cosmic Evolution Survey' (COSMOS) enables the study of the spectral energy distributions (SEDs) of active galactic nuclei (AGNs) because of the deep coverage and rich sampling of frequencies from X-ray to radio. Here we present an SED catalog of 413 X-ray (XMM-Newton)-selected type 1 (emission line FWHM > 2000 km s{sup -1}) AGNs with Magellan, SDSS, or VLT spectrum. The SEDs are corrected for Galactic extinction, broad emission line contributions, constrained variability, and host galaxy contribution. We present the mean SED and the dispersion SEDs after the above corrections in the rest-frame 1.4 GHz to 40 keV, and show examples of the variety of SEDs encountered. In the near-infrared to optical (rest frame {approx}8 {mu}m-4000 A), the photometry is complete for the whole sample and the mean SED is derived from detections only. Reddening and host galaxy contamination could account for a large fraction of the observed SED variety. The SEDs are all available online.

  16. HEAVY DUST OBSCURATION OF z = 7 GALAXIES IN A COSMOLOGICAL HYDRODYNAMIC SIMULATION

    SciTech Connect (OSTI)

    Kimm, Taysun; Cen, Renyue

    2013-10-10

    Hubble Space Telescope observations with the Wide Field Camera 3/Infrared reveal that galaxies at z ? 7 have very blue ultraviolet (UV) colors, consistent with these systems being dominated by young stellar populations with moderate or little attenuation by dust. We investigate UV and optical properties of the high-z galaxies in the standard cold dark matter model using a high-resolution adaptive mesh refinement cosmological hydrodynamic simulation. For this purpose, we perform panchromatic three-dimensional dust radiative transfer calculations on 198 galaxies of stellar mass 5 10{sup 8}-3 10{sup 10} M{sub ?} with three parameters: the dust-to-metal ratio, the extinction curve, and the fraction of directly escaped light from stars (f{sub esc}). Our stellar mass function is found to be in broad agreement with Gonzalez et al., independent of these parameters. We find that our heavily dust-attenuated galaxies (A{sub V} ? 1.8) can also reasonably match modest UV-optical colors, blue UV slopes, as well as UV luminosity functions, provided that a significant fraction (?10%) of light directly escapes from them. The observed UV slope and scatter are better explained with a Small-Magellanic-Cloud-type extinction curve, whereas a Milky-Way-type curve also predicts blue UV colors due to the 2175 bump. We expect that upcoming observations by the Atacama Large Millimeter/submillimeter Array will be able to test this heavily obscured model.

  17. Winds of low-metallicity OB-type stars: HST-COS spectroscopy in IC 1613

    SciTech Connect (OSTI)

    Garcia, Miriam; Najarro, Francisco; Herrero, Artemio; Urbaneja, Miguel Alejandro

    2014-06-10

    We present the first quantitative ultraviolet spectroscopic analysis of resolved OB stars in IC 1613. Because of its alleged very low metallicity (?1/10 Z {sub ?}, from H II regions), studies in this Local Group dwarf galaxy could become a significant step forward from the Small Magellanic Cloud (SMC) toward the extremely metal-poor massive stars of the early universe. We present HST-COS data covering the ?1150-1800 wavelength range with resolution R ? 2500. We find that the targets do exhibit wind features, and these are similar in strength to SMC stars. Wind terminal velocities were derived from the observed P Cygni profiles with the Sobolev plus Exact Integration method. The v {sub ?}-Z relationship has been revisited. The terminal velocity of IC 1613 O stars is clearly lower than Milky Way counterparts, but there is no clear difference between IC 1613 and SMC or LMC analog stars. We find no clear segregation with host galaxy in the terminal velocities of B-supergiants, nor in the v {sub ?}/v {sub esc} ratio of the whole OB star sample in any of the studied galaxies. Finally, we present the first evidence that the Fe-abundance of IC 1613 OB stars is similar to the SMC, which is in agreement with previous results on red supergiants. With the confirmed ?1/10 solar oxygen abundances of B-supergiants, our results indicate that IC 1613's ?/Fe ratio is sub-solar.

  18. Modeling transiting circumstellar disks: characterizing the newly discovered eclipsing disk system OGLE LMC-ECL-11893

    SciTech Connect (OSTI)

    Scott, Erin L.; Mamajek, Eric E.; Pecaut, Mark J.; Quillen, Alice C.; Moolekamp, Fred; Bell, Cameron P. M.

    2014-12-10

    We investigate the nature of the unusual eclipsing star OGLE LMC-ECL-11893 (OGLE J05172127-6900558) in the Large Magellanic Cloud recently reported by Dong et al. The eclipse period for this star is 468 days, and the eclipses exhibit a minimum of ?1.4 mag, preceded by a plateau of ?0.8 mag. Spectra and optical/IR photometry are consistent with the eclipsed star being a lightly reddened B9III star of inferred age ?150 Myr and mass ?4 M {sub ?}. The disk appears to have an outer radius of ?0.2 AU with predicted temperatures of ?1100-1400 K. We model the eclipses as being due to either a transiting geometrically thin dust disk or gaseous accretion disk around a secondary object; the debris disk produces a better fit. We speculate on the origin of such a dense circumstellar dust disk structure orbiting a relatively old low-mass companion, and on the similarities of this system to the previously discovered EE Cep.

  19. CHEMICAL SIGNATURE INDICATING A LACK OF MASSIVE STARS IN DWARF GALAXIES

    SciTech Connect (OSTI)

    Tsujimoto, Takuji, E-mail: taku.tsujimoto@nao.ac.jp [National Astronomical Observatory of Japan, Mitaka-shi, Tokyo 181-8588 (Japan)

    2011-08-01

    Growing evidence supports an unusual elemental feature appearing in nearby dwarf galaxies, especially dwarf spheroidals (dSphs), indicating a key process of galaxy evolution that is different from that of the Galaxy. In addition to the well-known deficiency of {alpha}-elements in dSphs, recent observations have clearly shown that s-process elements (Ba) are significantly enhanced relative to Fe, {alpha}-, and r-process elements. This enhancement occurs in some dSphs as well as in the Large Magellanic Cloud, but is unseen in the Galaxy. Here we report that this feature is evidence of the lack of very massive stars ({approx}>25 M{sub sun}) as predicted in the low star formation rate environment. We conclude that the unique elemental feature of dwarf galaxies including a low {alpha}/Fe ratio in some low-metallicity stars is, at least in some part, characterized by a different form of the initial mass function. We present a detailed model for the Fornax dSph galaxy and discuss its complex chemical enrichment history together with the nucleosynthesis site of the light s-process element Y.

  20. 25th Birthday Cern- Restaurant

    ScienceCinema (OSTI)

    None

    2011-04-25

    Cérémonie du 25ème anniversaire du Cern avec plusieurs orateurs et la présence de nombreux autorités cantonales et communales genevoises et personnalités, directeurs généraux, ministres, chercheurs.... Le conseiller féderal et chef du département des affaires étrangères de la confédération Monsieur Pierre Aubert prend la parole pour célébrer à la fois les résultats très remarquables de la coopération internationale en matière scientifique, mais aussi la volonté politique des états européens de mettre en commun leurs ressources pour faire oeuvre d'avenir. Un grand hommage est aussi donné aux deux directeurs disparus, les prof.Bakker et Gregory.

  1. Italian Exposition

    ScienceCinema (OSTI)

    None

    2011-04-25

    Le DG parle dans son allocution à l'occasion de l'exposition (suivi d'une visite)de la contribution du Cern à la création d'une espace de la technologie européenne. Il parle de la manière comment organiser des formes fructueuses de coopération et coordination internationales dans ce domaine. "Afin de renforcer encore notre relation avec l'industrie et intensifier le transfert de la technologie nous proposerons au ministre de recherche de poursuivre dans le cadre du programme EUREKA ensemble avec les industries des programmes concrètes." Le ministre italien prend ensuite la parole.

  2. Ward Co. Dunn Co. McLean Co. McHenry Co. Mountrail Co. McKenzie Co.

    U.S. Energy Information Administration (EIA) Indexed Site

    WHISKEY JOE WHITE ASH SPRING COULEE DES LACS MAGPIE HARTLAND BEICEGEL CREEK RANCH COULEE WINNER CRAZY MAN CREEK GROS VENTRE BANK W BULLSNAKE UPLAND COULEE REFUGE LARSON GARNET ALKALI CREEK PLUMER RATTLESNAKE POINT ELLSWORTH CHURCH BORDER HANSON GROVER HULSE COULEE SAKAKAWEA AURELIA ROUND TOP BUTTE GORHAM BUTTE W MARMON MANITOU SHEALEY CLAYTON SERGIS N SADDLE BUTTE HAYLAND CEDAR COULEE BOWLINE LITTLE BUTTE LONG CREEK RHOADES HEDBERG FILLMORE EIDSVOLD FAIRFIELD WOLF BAY TOBACCO GARDEN N SPRING

  3. Extreme Scale Unstructured Adaptive CFD: From Multiphase Flow to

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Aerodynamic Flow Control | Argonne Leadership Computing Facility Isosurface of instantaneous Q criterion colored by speed over a vertical tail Isosurface of instantaneous Q criterion colored by speed over a vertical tail at Re=3.5\ 10^5 of a DES simulation with a rudder deflection angle of 30 degrees and 12 unsteady jets active. Kenneth Jansen, University of Colorado at Boulder Extreme Scale Unstructured Adaptive CFD: From Multiphase Flow to Aerodynamic Flow Control PI Name: Kenneth Jansen

  4. Conference Salam/Musset

    ScienceCinema (OSTI)

    None

    2011-04-25

    Le DG L.Van Hove introduit le Prof. A.Salam né en 1926 dans l'ouest du Pakistan, un des gagnants du prix nobel de physique de cette année. Célébration de ses contributions théoriques mondialement connues. Après chaque discours, un petit historique est présenté par Paul Musset. Mention honorable aussi pour l'expérience Gargamelle et ses collaborateurs.

  5. Vinu Vikraman | Argonne National Laboratory

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Vinu Vikraman Postdoctoral Appointee Dr. Vikraman is currently working on the Dark Energy Survey. They are developing mass maps from the initial science verification data using weak lensing. They are also working on the gas profile measurement of clusters and groups using DES, SDSS and Planck data. Vinu is also working on a project testing gravity using cepheids, dwarf galaxies and stars. They developed a method to isolate screened regions in the local Universe based on N-body simulations. This

  6. 1

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Review of SHEBA Ice Pack/Ship Stability from ARM GPS Data K. B. Widener Pacific Northwest National Laboratory Richland, Washington K. Stamnes Stevens Institute of Technology Hoboken, New Jersey R. Storvold University of Alaska Fairbanks, Alaska B. D. Zak Sandia National Laboratories Albuquerque, New Mexico Introduction From October 1997 through October 1998, Atmospheric Radiation Measurement (ARM) Program instrumentation was deployed on and around the Canadian icebreaker Des Groseilliers as part

  7. Torleif Ericson 60th Birthday

    ScienceCinema (OSTI)

    None

    2011-04-25

    Plusieurs discours à l'occasion du 60me anniversaire de Torleif Ericson, physicien né à Lund (Suède), et remerciements pour son travail et son effort de relier la physique des particules à la physique nucléaire. A la fin de la cérémonie un document scientifique de 400 pages "die Festschrift" lui est remis comme cadeau d'anniversaire avec un grand nombre de contributions d'amis etc...

  8. Testing a Variety of Encryption Technologies

    SciTech Connect (OSTI)

    Henson, T J

    2001-04-09

    Review and test speeds of various encryption technologies using Entrust Software. Multiple encryption algorithms are included in the product. Algorithms tested were IDEA, CAST, DES, and RC2. Test consisted of taking a 7.7 MB Word document file which included complex graphics and timing encryption, decryption and signing. Encryption is discussed in the GIAC Kickstart section: Information Security: The Big Picture--Part VI.

  9. Inauguration LEP

    ScienceCinema (OSTI)

    None

    2011-04-25

    Le DG H.Schopper salue le président de la république française, F.Mitterand, le président de la confédaration suisse P.Aubert, ainsi que les ministres et représentants du gouvernement des 12 états membres pour la célébration et inauguration du LEP.

  10. History of Cern

    ScienceCinema (OSTI)

    None

    2011-04-25

    Cérémonie à l'occasion de l'apparition du premier volume du livre sur l'histoire du Cern, avec plusieurs personnes présentes qui jouaient un rôle important dans cette organisation européenne couronnée de succès grâce à l'esprit des membres fondateurs qui est et restera essentiel

  11. 1

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Ability of MM5 to Simulate Ice Clouds: Systematic Comparison between Simulated and Measured Fluxes and Lidar/Radar Profiles at Site Instrumental de Recherche par Teled'etrection Armospherique Atmospheric Observatory M. Chiriaco, R. Vautard, H. Chepfer, M. Haeffelin, Y. Wanherdrick, Y. Morille Institut Pierre Simon Laplace Laboratiore de Météorologie Dynamique Palaiseu, France A. Protat Institut Pierre Simon Laplace Centre d'études des Environnements Terrestre et Planétaires Paris, France J.

  12. 1

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Vertical Distribution of Aerosols Over the Atmospheric Radiation Measurement Southern Great Plains Site Measured versus Modeled R. Ferrare NASA Langley Research Center Hampton, Virginia D.D. Turner Pacific Northwest National Laboratory Richland, Washington M. Clayton SAIC/NASA Langley Research Center Hampton, Virginia S. Guibert and M. Schulz Laboratorie des Sciences du Climat et de l'Environment Toulouse, France M. Chin NASA Goddard Space Flight Center Greenbelt, Maryland Abstract Aerosol

  13. CONTACT

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    CONTACT The nuclear and materials science research ca- pabilities at LANSCE are operated as a DOE-des- ignated user facility in service to the nation. We provide neutron and proton beams as well as instrumentation and sample environments for basic, applied, industry, and defense-related re- search in nuclear physics and materials science. A yearly call invites proposals for beam time for experiments from other national laboratories, academia, and industry users. Proprietary and nonproprietary

  14. Present and Future Computing Requirements

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Computational Cosmology DES LSST Presenter: Salman Habib Argonne National Laboratory Jim Ahrens (LANL) Scott Dodelson (FNAL) Katrin Heitmann (ANL) Peter Nugent (LBNL) Anze Slosar (BNL) Risa Wechsler (SLAC) 1 Cosmic Frontier Computing Collaboration Computational Cosmology SciDAC-3 Project Ann Almgren (LBNL) Nick Gnedin (FNAL) Dave Higdon (LANL) Rob Ross (ANL) Martin White (UC Berkeley/ LBNL) Large Scale Production Computing and Storage Requirements for High Energy Physics Research A DOE Technical

  15. Pierre Darancet | Argonne National Laboratory

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Pierre Darancet Assistant Scientist, Center for Nanoscale Materials & Fellow, Northwestern Argonne Institute for Science and Engineering Education M.Sc., Applied Physics, Institut National des Sciences Appliquées M.Sc., Physics, Université Paul Sabatier Ph.D, Physics, Université Joseph Fourier Research Topics First-principles modeling of charge and energy transport in nanoscale materials. Optoelectronic properties of nanomaterials and heterogeneous interfaces Development of novel methods

  16. Hig Resolution Seismometer Insensitive to Extremely Strong Magnetic Fields

    SciTech Connect (OSTI)

    Abramovich, Igor A

    2009-07-14

    A highly sensitive broadband seismic sensor has been developed successfully to be used in beam focusing systems of particale accelerators. The sensor is completely insensitive to extremely strong magnetic fields and to hard radiation conditions that exist at the place of their installation. A unique remote sensor calibration method has been invented and implemented. Several such sensors were sold to LAPP (LAPP-IN2P3/CNRS-Universit de Savoie; Laboratoire d'Annecy-le-Vieux de Physique des Particules)

  17. Everest

    ScienceCinema (OSTI)

    None

    2011-04-25

    Chris Bonington, est né à Hampstead et a fait des études à University Collège School à Londres et au Royal Military Academy à Sundhorst. Il est un alpiniste mondialement connu qui a fait un grand nombre de premiers ascensions, comme celle de la face sud-ouest de l'Everest avec une équipe de 70 hommes en septembre 1975

  18. Modeling the transfer function for the Dark Energy Survey

    SciTech Connect (OSTI)

    Chang, C.; Busha, M. T.; Wechsler, R. H.; Refregier, A.; Amara, A.; Rykoff, E.; Becker, M. R.; Bruderer, C.; Gamper, L.; Leistedt, B.; Peiris, H.; Abbott, T.; Abdalla, F. B.; Balbinot, E.; Banerji, M.; Bernstein, R. A.; Bertin, E.; Brooks, D.; Carnero, A.; Desai, S.; da Costa, L. N.; Cunha, C. E.; Eifler, T.; Evrard, A. E.; Fausti Neto, A.; Gerdes, D.; Gruen, D.; James, D.; Kuehn, K.; Maia, M. A. G.; Makler, M.; Ogando, R.; Plazas, A.; Sanchez, E.; Santiago, B.; Schubnell, M.; Sevilla-Noarbe, I.; Smith, C.; Soares-Santos, M.; Suchyta, E.; Swanson, M. E. C.; Tarle, G.; Zuntz, J.

    2015-03-04

    We present a forward-modelling simulation framework designed to model the data products from the Dark Energy Survey (DES). This forward-model process can be thought of as a transfer function a mapping from cosmological and astronomical signals to the final data products used by the scientists. Using output from the cosmological simulations (the Blind Cosmology Challenge), we generate simulated images (the Ultra Fast Image Simulator, Berge et al. 2013) and catalogs representative of the DES data. In this work we simulate the 244 deg2 coadd images and catalogs in 5 bands for the DES Science Verification (SV) data. The simulation output is compared with the corresponding data to show that major characteristics of the images and catalogs can be captured. We also point out several directions of future improvements. Two practical examples, star/galaxy classification and proximity effects on object detection, are then used to demonstrate how one can use the simulations to address systematics issues in data analysis. With clear understanding of the simplifications in our model, we show that one can use the simulations side-by-side with data products to interpret the measurements. This forward modelling approach is generally applicable for other upcoming and future surveys. As a result, it provides a powerful tool for systematics studies which is sufficiently realistic and highly controllable.

  19. Ultra-broadband 2D electronic spectroscopy of carotenoid-bacteriochlorophyll interactions in the LH1 complex of a purple bacterium

    SciTech Connect (OSTI)

    Maiuri, Margherita; Rhault, Julien; Polli, Dario; Cerullo, Giulio; Carey, Anne-Marie; Hacking, Kirsty; Cogdell, Richard J.; Garavelli, Marco; Ler, Larry

    2015-06-07

    We investigate the excitation energy transfer (EET) pathways in the photosynthetic light harvesting 1 (LH1) complex of purple bacterium Rhodospirillum rubrum with ultra-broadband two-dimensional electronic spectroscopy (2DES). We employ a 2DES apparatus in the partially collinear geometry, using a passive birefringent interferometer to generate the phase-locked pump pulse pair. This scheme easily lends itself to two-color operation, by coupling a sub-10 fs visible pulse with a sub-15-fs near-infrared pulse. This unique pulse combination allows us to simultaneously track with extremely high temporal resolution both the dynamics of the photoexcited carotenoid spirilloxanthin (Spx) in the visible range and the EET between the Spx and the B890 bacterio-chlorophyll (BChl), whose Q{sub x} and Q{sub y} transitions peak at 585 and 881 nm, respectively, in the near-infrared. Global analysis of the one-color and two-color 2DES maps unravels different relaxation mechanisms in the LH1 complex: (i) the initial events of the internal conversion process within the Spx, (ii) the parallel EET from the first bright state S{sub 2} of the Spx towards the Q{sub x} state of the B890, and (iii) the internal conversion from Q{sub x} to Q{sub y} within the B890.

  20. Modeling the transfer function for the Dark Energy Survey

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Chang, C.; Busha, M. T.; Wechsler, R. H.; Refregier, A.; Amara, A.; Rykoff, E.; Becker, M. R.; Bruderer, C.; Gamper, L.; Leistedt, B.; et al

    2015-03-04

    We present a forward-modelling simulation framework designed to model the data products from the Dark Energy Survey (DES). This forward-model process can be thought of as a transfer function a mapping from cosmological and astronomical signals to the final data products used by the scientists. Using output from the cosmological simulations (the Blind Cosmology Challenge), we generate simulated images (the Ultra Fast Image Simulator, Berge et al. 2013) and catalogs representative of the DES data. In this work we simulate the 244 deg2 coadd images and catalogs in 5 bands for the DES Science Verification (SV) data. The simulationmoreoutput is compared with the corresponding data to show that major characteristics of the images and catalogs can be captured. We also point out several directions of future improvements. Two practical examples, star/galaxy classification and proximity effects on object detection, are then used to demonstrate how one can use the simulations to address systematics issues in data analysis. With clear understanding of the simplifications in our model, we show that one can use the simulations side-by-side with data products to interpret the measurements. This forward modelling approach is generally applicable for other upcoming and future surveys. As a result, it provides a powerful tool for systematics studies which is sufficiently realistic and highly controllable.less

  1. Modeling the Transfer Function for the Dark Energy Survey

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Chang, C.

    2015-03-04

    We present a forward-modeling simulation framework designed to model the data products from the Dark Energy Survey (DES). This forward-model process can be thought of as a transfer function—a mapping from cosmological/astronomical signals to the final data products used by the scientists. Using output from the cosmological simulations (the Blind Cosmology Challenge), we generate simulated images (the Ultra Fast Image Simulator) and catalogs representative of the DES data. In this work we demonstrate the framework by simulating the 244 deg2 coadd images and catalogs in five bands for the DES Science Verification data. The simulation output is compared with themore » corresponding data to show that major characteristics of the images and catalogs can be captured. We also point out several directions of future improvements. Two practical examples—star-galaxy classification and proximity effects on object detection—are then used to illustrate how one can use the simulations to address systematics issues in data analysis. With clear understanding of the simplifications in our model, we show that one can use the simulations side-by-side with data products to interpret the measurements. This forward modeling approach is generally applicable for other upcoming and future surveys. It provides a powerful tool for systematics studies that is sufficiently realistic and highly controllable.« less

  2. The geometric factor of electrostatic plasma analyzers: A case study from the Fast Plasma Investigation for the Magnetospheric Multiscale mission

    SciTech Connect (OSTI)

    Collinson, Glyn A.; Dorelli, John C.; Moore, Thomas E.; Pollock, Craig; Mariano, Al; Shappirio, Mark D.; Adrian, Mark L.; Avanov, Levon A.; Lewis, Gethyn R.; Kataria, Dhiren O.; Bedington, Robert; Owen, Christopher J.; Walsh, Andrew P.; Arridge, Chris S.; Gliese, Ulrik; Barrie, Alexander C.; Tucker, Corey

    2012-03-15

    We report our findings comparing the geometric factor (GF) as determined from simulations and laboratory measurements of the new Dual Electron Spectrometer (DES) being developed at NASA Goddard Space Flight Center as part of the Fast Plasma Investigation on NASA's Magnetospheric Multiscale mission. Particle simulations are increasingly playing an essential role in the design and calibration of electrostatic analyzers, facilitating the identification and mitigation of the many sources of systematic error present in laboratory calibration. While equations for laboratory measurement of the GF have been described in the literature, these are not directly applicable to simulation since the two are carried out under substantially different assumptions and conditions, making direct comparison very challenging. Starting from first principles, we derive generalized expressions for the determination of the GF in simulation and laboratory, and discuss how we have estimated errors in both cases. Finally, we apply these equations to the new DES instrument and show that the results agree within errors. Thus we show that the techniques presented here will produce consistent results between laboratory and simulation, and present the first description of the performance of the new DES instrument in the literature.

  3. LHC, le Big Bang en éprouvette

    ScienceCinema (OSTI)

    None

    2011-10-06

    Notre compréhension de l?Univers est en train de changer? Bar des Sciences - Tout public Débat modéré par Marie-Odile Montchicourt, journaliste de France Info. Evenement en vidéoconférence entre le Globe de la science et de l?innovation, le bar le Baloard de Montpellier et la Maison des Métallos à Paris. Intervenants au CERN : Philippe Charpentier et Daniel Froideveaux, physiciens au CERN. Intervenants à Paris : Vincent Bontemps, philosophe et chercheur au CEA ; Jacques Arnould, philosophe, historien des sciences et théologien, Jean-Jacques Beineix, réalisateur, producteur, scénariste de cinéma. Intervenants à Montpellier (LPTA) : André Neveu, physicien théoricien et directeur de recherche au CNRS ; Gilbert Moultaka, physicien théoricien et chargé de recherche au CNRS. Partenariat : CERN, CEA, IN2P3, Université MPL2 (LPTA) Dans le cadre de la Fête de la science 2008

  4. La supraconductivité a 100 ans !

    ScienceCinema (OSTI)

    None

    2011-10-06

    Il y a 100 ans, le 8 avril 1911, une découverte majeure était réalisée : celle de la supraconductivité. La supraconductivité est la caractéristique qu?ont certains métaux et alliages de perdre toute résistance électrique en dessous d?une température donnée. Cette renversante découverte, réalisée de manière presque fortuite par Kammerlingh Onnes de l?Université de Leyde (Pays-Bas) et son étudiant Gilles Holst, a ouvert un nouveau champ de recherche en physique et de fabuleuses perspectives d?applications technologiques. Du point de vue scientifique, la supraconductivité est en effet l?une des rares manifestations de la physique quantique à l?échelle macroscopique.  Du point de vue des retombées techniques, elle est porteuse d?applications majeures dans le domaine de la santé, des communications et de l?énergie. 100 ans après, les physiciens n?ont toujours pas fini d?explorer ce phénomène et ses applications. Le CERN abrite des applications de la supraconductivité à des échelles inédites. L?accélérateur de particules LHC, avec ses milliers d?aimants supraconducteurs répartis sur 27 kilomètres de circonférence, est en effet la plus grande application mondiale de la supraconductivité. Il ne pourrait exister sans elle.  Le CERN fête donc la découverte de la supraconductivité avec une conférence exceptionnelle donnée par Philippe Lebrun. Au cours de cette conférence, l?expérience historique de Kammerlingh Onnes sera reproduite. Philippe Lebrun racontera l?histoire de cette étonnante découverte, en la replaçant dans le contexte scientifique de l?époque. Il racontera les développements scientifiques et les applications du premier siècle de la supraconductivité. Conférence en français Merci de bien vouloir vous inscrire au : +41 22 767 76 76 ou cern.reception@cern.ch

  5. La supraconductivité a 100 ans !

    SciTech Connect (OSTI)

    2011-04-14

    Il y a 100 ans, le 8 avril 1911, une découverte majeure était réalisée : celle de la supraconductivité. La supraconductivité est la caractéristique qu’ont certains métaux et alliages de perdre toute résistance électrique en dessous d’une température donnée. Cette renversante découverte, réalisée de manière presque fortuite par Kammerlingh Onnes de l’Université de Leyde (Pays-Bas) et son étudiant Gilles Holst, a ouvert un nouveau champ de recherche en physique et de fabuleuses perspectives d’applications technologiques. Du point de vue scientifique, la supraconductivité est en effet l’une des rares manifestations de la physique quantique à l’échelle macroscopique.  Du point de vue des retombées techniques, elle est porteuse d’applications majeures dans le domaine de la santé, des communications et de l’énergie. 100 ans après, les physiciens n’ont toujours pas fini d’explorer ce phénomène et ses applications. Le CERN abrite des applications de la supraconductivité à des échelles inédites. L’accélérateur de particules LHC, avec ses milliers d’aimants supraconducteurs répartis sur 27 kilomètres de circonférence, est en effet la plus grande application mondiale de la supraconductivité. Il ne pourrait exister sans elle.  Le CERN fête donc la découverte de la supraconductivité avec une conférence exceptionnelle donnée par Philippe Lebrun. Au cours de cette conférence, l’expérience historique de Kammerlingh Onnes sera reproduite. Philippe Lebrun racontera l’histoire de cette étonnante découverte, en la replaçant dans le contexte scientifique de l’époque. Il racontera les développements scientifiques et les applications du premier siècle de la supraconductivité. Conférence en français Merci de bien vouloir vous inscrire au : +41 22 767 76 76 ou cern.reception@cern.ch

  6. DETECTIONS OF FAINT Ly{alpha} EMITTERS AT z = 5.7: GALAXY BUILDING BLOCKS AND ENGINES OF REIONIZATION

    SciTech Connect (OSTI)

    Dressler, Alan; McCarthy, Patrick; Martin, Crystal L.; Henry, Alaina; Sawicki, Marcin E-mail: sawicki@ap.smu.ca

    2011-10-20

    We report results of an unprecedentedly deep, blind search for Ly{alpha} emitters (LAEs) at z = 5.7 using the Inamori-Magellan Areal Camera and Spectrograph (IMACS), with the goal of identifying missing sources of reionization that could also be basic building blocks for today's L* galaxies. We describe how improvements in wide field imaging with the Baade telescope, upgrades to IMACS, and the accumulation of {approx}20 hr of integration per field in excellent seeing led to the detection of single-emission-line sources as faint as F {approx} 2 x 10{sup -18} erg s{sup -1} cm{sup -2}, a sensitivity five times deeper than our first search. A reasonable correction for foreground interlopers implies a steep rise of approximately an order of magnitude in source density for a factor of four drop in flux, from F = 10{sup -17.0} erg s{sup -1} cm{sup -2} to F = 10{sup -17.6} (2.5 x 10{sup -18}) erg s{sup -1} cm{sup -2}. At this flux the putative LAEs have reached a surface density of {approx}1 arcmin{sup -2}-a comoving volume density of 4 x 10{sup -3} Mpc{sup -3}, several times the density of L* galaxies today. Such a population of faint LAEs would account for a significant fraction of the critical flux density required to complete reionization at this epoch, and would be good candidates for building blocks of stellar mass {approx}10{sup 8}-10{sup 9} M{sub sun} for the young galaxies of this epoch.

  7. The mid-infrared appearance of the galactic mini-starburst W49A

    SciTech Connect (OSTI)

    Stock, D. J.; Peeters, E.; Choi, W. D.-Y.; Shannon, M. J.

    2014-08-20

    The massive star-forming region W49A represents one of the largest complexes of massive star formation present in the Milky Way and contains at least 50 young massive stars still enshrouded in their natal molecular cloud. We employ Spitzer/Infrared Spectrometer spectral mapping observations of the northern part of W49A to investigate the mid-infrared (MIR) spatial appearance of the polycyclic aromatic hydrocarbon (PAH) bands, PAH plateau features, atomic lines, and continuum emission. We examine the spatial variations of the MIR emission components in slices through two of the ultra-compact-H II (UC-H II) regions. We find that the PAH bands reproduce known trends, with the caveat that the 6.2 μm PAH band seems to decouple from the other ionized PAH bands in some of the UC-H II regions—an effect previously observed only in one other object: the giant star forming region N66 in the Large Magellanic Cloud. Furthermore, we compare the nature of the emission surrounding W49A to that of 'diffuse' sightlines. It is found that the surrounding emission can be explained by line of sight emission and does not represent true 'diffuse' material. Additionally, we examine the MIR appearance of star formation on various scales from UC-H II regions to starburst galaxies, including a discussion of the fraction of PAH emission in the 8 μm IRAC filter. We find that the MIR appearance of W49A is that of a starburst on large scales, yet its individual components are consistent with other galactic H II regions.

  8. THE CARNEGIE HUBBLE PROGRAM: THE LEAVITT LAW AT 3.6 AND 4.5 {mu}m IN THE MILKY WAY

    SciTech Connect (OSTI)

    Monson, Andrew J.; Freedman, Wendy L.; Madore, Barry F.; Persson, S. E.; Scowcroft, Victoria; Seibert, Mark; Rigby, Jane R. E-mail: wendy@obs.carnegiescience.edu E-mail: persson@obs.carnegiescience.edu E-mail: mseibert@obs.carnegiescience.edu

    2012-11-10

    The Carnegie Hubble Program (CHP) is designed to calibrate the extragalactic distance scale using data from the post-cryogenic era of the Spitzer Space Telescope. The ultimate goal of the CHP is a systematic improvement in the distance scale leading to a determination of the Hubble constant to within an accuracy of 2%. This paper focuses on the measurement and calibration of the Galactic Cepheid period-luminosity (PL, Leavitt) relation using the warm Spitzer/IRAC 1 and 2 bands at 3.6 and 4.5 {mu}m. We present photometric measurements covering the period range 4-70 days for 37 Galactic Cepheids. Data at 24 phase points were collected for each star. Three PL relations of the form M = a(log (P) - 1) + b are derived. The method adopted here takes the slope a to be -3.31, as determined from the Spitzer Large Magellanic Cloud (LMC) data of Scowcroft et al. Using the geometric Hubble Space Telescope guide-star distances to 10 Galactic Cepheids, we find a calibrated 3.6 {mu}m PL zero point of -5.80 {+-} 0.03. Together with our value for the LMC zero point, we determine a reddening-corrected distance modulus of 18.48 {+-} 0.04 mag to the LMC. The mid-IR period-color diagram and the [3.6]-[4.5] color variation with phase are interpreted in terms of CO absorption at 4.5 {mu}m. This situation compromises the use of the 4.5 {mu}m data for distance determinations.

  9. Lyman Alpha Emitting Galaxies at 2 < z < 3: Towards a Calibrated Probe of Dark Energy

    SciTech Connect (OSTI)

    Caryl Gronwall

    2012-12-03

    The goal of this project was to establish the physical properties of Ly{alpha} emitting galaxies from redshifts of 2 to 3 in order to better calibrate the use of LAEs as probes of the large scale structure of the universe for upcoming dark energy experiments, such as the Hobby Eberly Telescope Dark Energy Experiment (HETDEX). We have obtained narrow-band imaging of the Extended Chandra Deep Field South (ECDF-S) in two different narrow-band filters centered at Ly{alpha} at z=2.1 and 3.1. The resulting of samples of LAEs were used to determine the LAE luminosity function, equivalent width distribution and clustering properties (bias) of LAEs at these redshifts. While the results from the ECDF-S appear robust, they are based on a single field. To explore the effects of cosmic variance and galaxy environment on the physical properties of LAEs, we have also obtained narrow-band data at both redshifts (z = 2:1 and 3:1) in three additional fields (SDSS 1030+-05, the Extended Hubble Deep Field South, and CW 1255+01). The narrow-band imaging data has been reduced and LAE catalogs are being generated. We have calculated preliminary luminosity functions, equivalent width distributions, and clustering properties. We have also obtained follow-up spectroscopy in the optical (using VLT/FORS) and in the near-infrared (using Magellan/MMIRS). Since individual LAEs have too little S/N to enable meaningful fits for stellar population parameters, our previous work has analyzed stacked Spectral Energy Distributions (SEDs). SED fitting was performed on several subsets of LAEs selected by their rest-UV luminosity, UV spectral slope, Ly alpha luminosity, Equivalent Width, or rest-optical (IRAC) luminosity.

  10. SIMILARITIES IN POPULATIONS OF STAR CLUSTERS

    SciTech Connect (OSTI)

    Fall, S. Michael; Chandar, Rupali E-mail: rupali.chandar@utoledo.edu

    2012-06-20

    We compare the observed mass functions and age distributions of star clusters in six well-studied galaxies: the Milky Way, Magellanic Clouds, M83, M51, and Antennae. In combination, these distributions span wide ranges of mass and age: 10{sup 2} {approx}< M/M{sub Sun} {approx}< 10{sup 6} and 10{sup 6} {approx}< {tau}/yr {approx}< 10{sup 9}. We confirm that the distributions are well represented by power laws: dN/dM{proportional_to}M{sup {beta}} with {beta} Almost-Equal-To -1.9 and dN/d{tau}{proportional_to}{tau}{sup {gamma}} with {gamma} Almost-Equal-To -0.8. The mass and age distributions are approximately independent of each other, ruling out simple models of mass-dependent disruption. As expected, there are minor differences among the exponents at a level close to the true uncertainties, {epsilon}{sub {beta}} {approx} {epsilon}{sub {gamma}} {approx} 0.1-0.2. However, the overwhelming impression is the similarity of the mass functions and age distributions of clusters in these different galaxies, including giant and dwarf, quiescent and interacting galaxies. This is an important empirical result, justifying terms such as 'universal' or 'quasi-universal'. We provide a partial theoretical explanation for these observations in terms of physical processes operating during the formation and disruption of the clusters, including star formation and feedback, subsequent stellar mass loss, and tidal interactions with passing molecular clouds. A full explanation will require additional information about the molecular clumps and star clusters in galaxies beyond the Milky Way.

  11. Consequences of dynamical disruption and mass segregation for the binary frequencies of star clusters

    SciTech Connect (OSTI)

    Geller, Aaron M.; De Grijs, Richard; Li, Chengyuan; Hurley, Jarrod R.

    2013-12-10

    The massive (13,000-26,000 M {sub ?}) and young (15-30 Myr) Large Magellanic Cloud star cluster NGC 1818 reveals an unexpected increasing binary frequency with radius for F-type stars (1.3-2.2 M {sub ?}). This is in contrast to many older star clusters that show a decreasing binary frequency with radius. We study this phenomenon with sophisticated N-body modeling, exploring a range of initial conditions, from smooth virialized density distributions to highly substructured and collapsing configurations. We find that many of these models can reproduce the cluster's observed properties, although with a modest preference for substructured initial conditions. Our models produce the observed radial trend in binary frequency through disruption of soft binaries (with semi-major axes, a ? 3000 AU), on approximately a crossing time (?5.4 Myr), preferentially in the cluster core. Mass segregation subsequently causes the binaries to sink toward the core. After roughly one initial half-mass relaxation time (t {sub rh}(0) ? 340 Myr) the radial binary frequency distribution becomes bimodal, the innermost binaries having already segregated toward the core, leaving a minimum in the radial binary frequency distribution that marches outward with time. After 4-6 t {sub rh}(0), the rising distribution in the halo disappears, leaving a radial distribution that rises only toward the core. Thus, both a radial binary frequency distribution that falls toward the core (as observed for NGC 1818) and one that rises toward the core (as for older star clusters) can arise naturally from the same evolutionary sequence owing to binary disruption and mass segregation in rich star clusters.

  12. A CLOSE-PAIR ANALYSIS OF DAMP MERGERS AT INTERMEDIATE REDSHIFTS

    SciTech Connect (OSTI)

    Chou, Richard C. Y.; Abraham, Roberto G.; Bridge, Carrie R. E-mail: abraham@astro.utoronto.ca

    2012-12-01

    We have studied the kinematics of {approx}2800 candidate close-pair galaxies at 0.1 < z < 1.2 identified from the Canada-France-Hawaii Telescope Legacy Survey fields. Spectra of these systems were obtained using spectrometers on the 6.5 m Magellan and 5 m Hale telescopes. These data allow us to constrain the rate of dry mergers at intermediate redshifts and to test the 'hot halo' model for quenching of star formation. Using virial radii estimated from the correlation between dynamical and stellar masses published by Leauthaud et al., we find that around 1/5 of our candidate pairs are likely to share a common dark matter halo (our metric for close physical association). These pairs are divided into red-red, blue-red, and blue-blue systems using the rest-frame colors classification method introduced in Chou et al.. Galaxies classified as red in our sample have very low star formation rates, but they need not be totally quiescent, and hence we refer to them as 'damp', rather than 'dry', systems. After correcting for known selection effects, the fraction of blue-blue pairs is significantly greater than that of red-red and blue-red pairs. Red-red pairs are almost entirely absent from our sample, suggesting that damp mergers are rare at z {approx} 0.5. Our data support models with a short merging timescale (<0.5 Gyr) in which star formation is enhanced in the early phase of mergers, but quenched in the late phase. Hot halo models may explain this behavior, but only if virial shocks that heat gas are inefficient until major mergers are nearly complete.

  13. DETERMINING THE NATURE OF THE EXTENDED H I STRUCTURE AROUND LITTLE THINGS DWARF GALAXY NGC 1569

    SciTech Connect (OSTI)

    Johnson, Megan

    2013-06-15

    This work presents an extended, neutral hydrogen emission map around Magellanic-type dwarf irregular galaxy (dIm) NGC 1569. In the spring of 2010, the Robert C. Byrd Green Bank Telescope was used to map a 9 Degree-Sign Multiplication-Sign 2 Degree-Sign region in H I line emission that includes NGC 1569 and IC 342 as well as two other dwarf galaxies. The primary objective for these observations was to search for structures potentially connecting NGC 1569 with IC 342 group members in order to trace previous interactions and thus, provide an explanation for the starburst and peculiar kinematics prevalent in NGC 1569. A large, half-degree diameter H I cloud was detected that shares the same position and velocity as NGC 1569. Also, two long structures were discovered that are reminiscent of intergalactic filaments extending out in a V-shaped manner from NGC 1569 toward UGCA 92, a nearby dwarf galaxy. These filamentary structures extend for about 1. Degree-Sign 5, which is 77 kpc at NGC 1569. There is a continuous velocity succession with the 0. Degree-Sign 5 H I cloud, filaments, and main body of the galaxy. The 0. Degree-Sign 5 H I cloud and filamentary structures may be foreground Milky Way, but are suggestive as possible remnants of an interaction between NGC 1569 and UGCA 92. The data also show two tidal tails extending from UGCA 86 and IC 342, respectively. These structures may be part of a continuous H I bridge but more data are needed to determine if this is the case.

  14. MAIN-BELT COMET P/2012 T1 (PANSTARRS)

    SciTech Connect (OSTI)

    Hsieh, Henry H.; Kaluna, Heather M.; Yang Bin; Haghighipour, Nader; Micheli, Marco; Denneau, Larry; Jedicke, Robert; Kleyna, Jan; Veres, Peter; Wainscoat, Richard J.; Ansdell, Megan; Elliott, Garrett T.; Keane, Jacqueline V.; Meech, Karen J.; Riesen, Timm E.; Sonnett, Sarah; Novakovic, Bojan; Fitzsimmons, Alan; Moskovitz, Nicholas A.; Sheppard, Scott S.; and others

    2013-07-01

    We present initial results from observations and numerical analyses aimed at characterizing the main-belt comet P/2012 T1 (PANSTARRS). Optical monitoring observations were made between 2012 October and 2013 February using the University of Hawaii 2.2 m telescope, the Keck I telescope, the Baade and Clay Magellan telescopes, Faulkes Telescope South, the Perkins Telescope at Lowell Observatory, and the Southern Astrophysical Research Telescope. The object's intrinsic brightness approximately doubles from the time of its discovery in early October until mid-November and then decreases by {approx}60% between late December and early February, similar to photometric behavior exhibited by several other main-belt comets and unlike that exhibited by disrupted asteroid (596) Scheila. We also used Keck to conduct spectroscopic searches for CN emission as well as absorption at 0.7 {mu}m that could indicate the presence of hydrated minerals, finding an upper limit CN production rate of Q{sub CN} < 1.5 Multiplication-Sign 10{sup 23} mol s{sup -1}, from which we infer a water production rate of Q{sub H{sub 2O}}<5 Multiplication-Sign 10{sup 25} mol s{sup -1}, and no evidence of the presence of hydrated minerals. Numerical simulations indicate that P/2012 T1 is largely dynamically stable for >100 Myr and is unlikely to be a recently implanted interloper from the outer solar system, while a search for potential asteroid family associations reveals that it is dynamically linked to the {approx}155 Myr old Lixiaohua asteroid family.

  15. RESOLVED NEAR-INFRARED SPECTROSCOPY OF WISE J104915.57-531906.1AB: A FLUX-REVERSAL BINARY AT THE L DWARF/T DWARF TRANSITION

    SciTech Connect (OSTI)

    Burgasser, Adam J.; Sheppard, Scott S.; Luhman, K. L.

    2013-08-01

    We report resolved near-infrared spectroscopy and photometry of the recently identified brown dwarf binary WISE J104915.57-531906.1AB, located 2.02 {+-} 0.15 pc from the Sun. Low-resolution spectral data from Magellan/FIRE and IRTF/SpeX reveal strong H{sub 2}O and CO absorption features in the spectra of both components, while the secondary also exhibits weak CH{sub 4} absorption at 1.6 {mu}m and 2.2 {mu}m. Spectral indices and comparison to low-resolution spectral standards indicate component types of L7.5 and T0.5 {+-} 1, the former consistent with the optical classification of the primary. Both sources also have unusually red spectral energy distributions for their spectral types, which we attribute to enhanced condensate opacity (thick clouds). Relative photometry reveals a flux reversal between the J and K bands, with the T dwarf component being brighter in the 0.95-1.3 {mu}m region ({Delta}J = -0.31 {+-} 0.05). As with other L/T transition binaries, this reversal likely reflects the depletion of condensate opacity in the T dwarf, with the contrast enhanced by the thick clouds present in the photosphere of the L dwarf primary. The 1 {mu}m flux from the T dwarf most likely emerges from gaps in its cloud layer, as suggested by the significant optical variability detected from this source by Gillon et al. Component mass measurements of the WISE J1049-5319AB system through astrometric and component radial velocity monitoring may resolve the current debate as to whether the loss of photospheric condensate clouds at the L dwarf/T dwarf boundary is a slow or rapid process, a conceivable endeavor given its proximity, brightness, small separation (3.1 {+-} 0.3 AU), and reasonable orbital period (20-30 yr)

  16. The Gemini NICI planet-finding campaign: the orbit of the young exoplanet ? Pictoris b

    SciTech Connect (OSTI)

    Nielsen, Eric L.; Liu, Michael C.; Chun, Mark; Ftaclas, Christ; Wahhaj, Zahed; Biller, Beth A.; Hayward, Thomas L.; Kuchner, Marc J.; Rodigas, Timothy J.; Toomey, Douglas W.

    2014-10-20

    We present new astrometry for the young (12-21 Myr) exoplanet ? Pictoris b taken with the Gemini/NICI and Magellan/MagAO instruments between 2009 and 2012. The high dynamic range of our observations allows us to measure the relative position of ? Pic b with respect to its primary star with greater accuracy than previous observations. Based on a Markov Chain Monte Carlo analysis, we find the planet has an orbital semi-major axis of 9.1{sub ?0.5}{sup +5.3} AU and orbital eccentricity <0.15 at 68% confidence (with 95% confidence intervals of 8.2-48 AU and 0.00-0.82 for semi-major axis and eccentricity, respectively, due to a long narrow degenerate tail between the two). We find that the planet has reached its maximum projected elongation, enabling higher precision determination of the orbital parameters than previously possible, and that the planet's projected separation is currently decreasing. With unsaturated data of the entire ? Pic system (primary star, planet, and disk) obtained thanks to NICI's semi-transparent focal plane mask, we are able to tightly constrain the relative orientation of the circumstellar components. We find the orbital plane of the planet lies between the inner and outer disks: the position angle (P.A.) of nodes for the planet's orbit (211.8 0.3) is 7.4? greater than the P.A. of the spine of the outer disk and 3.2? less than the warped inner disk P.A., indicating the disk is not collisionally relaxed. Finally, for the first time we are able to dynamically constrain the mass of the primary star ? Pic to 1.76{sub ?0.17}{sup +0.18} M {sub ?}.

  17. FIRE SPECTROSCOPY OF FIVE LATE-TYPE T DWARFS DISCOVERED WITH THE WIDE-FIELD INFRARED SURVEY EXPLORER

    SciTech Connect (OSTI)

    Burgasser, Adam J.; Cushing, Michael C.; Mainzer, A.; Bauer, James M.; Kirkpatrick, J. Davy; Gelino, Christopher R.; Griffith, Roger L.; Marsh, Kenneth A.; Looper, Dagny L.; Tinney, Christopher; Simcoe, Robert A.; Bochanski, John J.; Skrutskie, Michael F.; Thompson, Maggie A.; Wright, Edward L.

    2011-07-10

    We present the discovery of five late-type T dwarfs identified with the Wide-field Infrared Survey Explorer (WISE). Low-resolution near-infrared spectroscopy obtained with the Magellan Folded-port InfraRed Echellette reveal strong H{sub 2}O and CH{sub 4} absorption in all five sources, and spectral indices and comparison to spectral templates indicate classifications ranging from T5.5 to T8.5:. The spectrum of the latest-type source, WISE J1812+2721, is an excellent match to that of the T8.5 companion brown dwarf Wolf 940B. WISE-based spectrophotometric distance estimates place these T dwarfs at 12-13 pc from the Sun, assuming they are single. Preliminary fits of the spectral data to the atmosphere models of Saumon and Marley indicate effective temperatures ranging from 600 K to 930 K, both cloudy and cloud-free atmospheres, and a broad range of ages and masses. In particular, two sources show evidence of both low surface gravity and cloudy atmospheres, tentatively supporting a trend noted in other young brown dwarfs and exoplanets. In contrast, the high proper motion T dwarf WISE J2018-7423 exhibits a suppressed K-band peak and blue spectrophotometric J - K colors indicative of an old, massive brown dwarf; however, it lacks the broadened Y-band peak seen in metal-poor counterparts. These results illustrate the broad diversity of low-temperature brown dwarfs that will be uncovered with WISE.

  18. KAT-7 SCIENCE VERIFICATION: USING H I OBSERVATIONS OF NGC 3109 TO UNDERSTAND ITS KINEMATICS AND MASS DISTRIBUTION

    SciTech Connect (OSTI)

    Carignan, C.; Frank, B. S.; Hess, K. M.; Lucero, D. M.; Randriamampandry, T. H. [Department of Astronomy, University of Cape Town, Private Bag X3, Rondebosch 7701 (South Africa); Goedhart, S.; Passmoor, S. S., E-mail: ccarignan@ast.uct.ac.za [SKA South Africa, The Park, Park Road, Pinelands, 7405 (South Africa)

    2013-09-15

    H I observations of the Magellanic-type spiral NGC 3109, obtained with the seven dish Karoo Array Telescope (KAT-7), are used to analyze its mass distribution. Our results are compared to those obtained using Very Large Array (VLA) data. KAT-7 is a pathfinder of the Square Kilometer Array precursor MeerKAT, which is under construction. The short baselines and low system temperature of the telescope make it sensitive to large-scale, low surface brightness emission. The new observations with KAT-7 allow the measurement of the rotation curve (RC) of NGC 3109 out to 32', doubling the angular extent of existing measurements. A total H I mass of 4.6 Multiplication-Sign 10{sup 8} M{sub Sun} is derived, 40% more than what is detected by the VLA observations. The observationally motivated pseudo-isothermal dark matter (DM) halo model can reproduce the observed RC very well, but the cosmologically motivated Navarro-Frenk-White DM model gives a much poorer fit to the data. While having a more accurate gas distribution has reduced the discrepancy between the observed RC and the MOdified Newtonian Dynamics (MOND) models, this is done at the expense of having to use unrealistic mass-to-light ratios for the stellar disk and/or very large values for the MOND universal constant a{sub 0}. Different distances or H I contents cannot reconcile MOND with the observed kinematics, in view of the small errors on these two quantities. As with many slowly rotating gas-rich galaxies studied recently, the present result for NGC 3109 continues to pose a serious challenge to the MOND theory.

  19. DISCOVERY OF A NEW FAINT DWARF GALAXY ASSOCIATED WITH NGC 253

    SciTech Connect (OSTI)

    Sand, D. J.; Crnojević, D.; Strader, J.; Toloba, E.; Guhathakurta, P.; Caldwell, N.; McLeod, B.; Seth, A. C.

    2014-09-20

    We report the discovery of a new faint dwarf galaxy, which we dub Scl-MM-Dw1, at a projected distance of ∼65 kpc from the spiral galaxy NGC 253. The discovery results from the Panoramic Imaging Survey of Centaurus and Sculptor (PISCeS), a program with the Magellan/Megacam imager to study faint substructure in resolved stellar light around massive galaxies outside of the Local Group. We measure a tip of the red giant branch distance to Scl-MM-Dw1 of D = 3.9 ± 0.5 Mpc, consistent with that of NGC 253, making their association likely. The new dwarf's stellar population is complex, with an old, metal-poor red giant branch (≳10 Gyr, [Fe/H] ∼ –2), and an asymptotic giant branch with an age of ∼500 Myr. Scl-MM-Dw1 has a half-light radius of r{sub h} = 340 ± 50 pc and an absolute magnitude of M{sub V}  = –10.3 ± 0.6 mag, comparable to the Milky Way's satellites at the same luminosity. Once complete, our imaging survey of NGC 253 and other nearby massive galaxies will provide a census of faint substructure in halos beyond the Local Group, both to put our own environment into context and to confront models of hierarchical structure formation.

  20. AN OPTICALLY OBSCURED AGN IN A LOW MASS, IRREGULAR DWARF GALAXY: A MULTI-WAVELENGTH ANALYSIS OF J1329+3234

    SciTech Connect (OSTI)

    Secrest, N. J.; Satyapal, S.; Gliozzi, M.; Rothberg, B.; Mowry, W. S.; Rosenberg, J. L. [Department of Physics and Astronomy, George Mason University, MS 3F3, 4400 University Drive, Fairfax, VA 22030 (United States); Ellison, S. L. [Department of Physics and Astronomy, University of Victoria, Victoria, BC V8P 1A1 (Canada); Fischer, J.; Schmitt, H. [Naval Research Laboratory, Remote Sensing Division, 4555 Overlook Avenue SW, Washington, DC 20375 (United States)

    2015-01-01

    Supermassive black holes (SMBHs) are found ubiquitously in large, bulge-dominated galaxies throughout the local universe, yet little is known about their presence and properties in bulgeless and low-mass galaxies. This is a significant deficiency, since the mass distribution and occupation fraction of nonstellar black holes provide important observational constraints on SMBH seed formation theories and many dwarf galaxies have not undergone major mergers that would erase information on their original black hole population. Using data from the Wide-field Infrared Survey Explorer, we discovered hundreds of bulgeless and dwarf galaxies that display mid-infrared signatures of extremely hot dust highly suggestive of powerful accreting massive black holes, despite having no signatures of black hole activity at optical wavelengths. Here we report, in our first follow-up X-ray investigation of this population, that the irregular dwarf galaxy J132932.41+323417.0 (z = 0.0156) contains a hard, unresolved X-ray source detected by XMM-Newton with luminosity L {sub 2-10} {sub keV} = 2.4 10{sup 40}ergs{sup 1}, over two orders of magnitude greater than that expected from star formation, strongly suggestive of the presence of an accreting massive black hole. While enhanced X-ray emission and hot dust can be produced in extremely low metallicity environments, J132932.41+323417.0 is not extremely metal poor (?40% solar). With a stellar mass of 2.0 10{sup 8} M {sub ?}, this galaxy is similar in mass to the Small Magellanic Cloud, and is one of the lowest mass galaxies with evidence for a massive nuclear black hole currently known.

  1. WEAK GALACTIC HALO-DWARF SPHEROIDAL CONNECTION FROM RR LYRAE STARS

    SciTech Connect (OSTI)

    Fiorentino, Giuliana [INAF-Osservatorio Astronomico di Bologna, via Ranzani 1, I-40127 Bologna (Italy); Bono, Giuseppe [Dipartimento di Fisica, Universit di Roma Tor Vergata, Via della Ricerca Scientifica 1, I-00133 Roma (Italy); Monelli, Matteo; Gallart, Carme; Martnez-Vsquez, Clara E. [Instituto de Astrofsica de Canarias, Calle Via Lactea s/n, E-38205 La Laguna, Tenerife (Spain); Stetson, Peter B. [National Research Council, 5071 West Saanich Road, Victoria, BC V9E 2E7 (Canada); Tolstoy, Eline [Kapteyn Astronomical Institute, University of Groningen, Postbus 800, 9700 AV Groningen (Netherlands); Salaris, Maurizio [Astrophysics Research Institute, Liverpool John Moores University IC2, Liverpool Science Park, 146 Brownlow Hill, Liverpool L35RF (United Kingdom); Bernard, Edouard J., E-mail: giuliana.fiorentino@oabo.inaf.it [SUPA, Institute for Astronomy, University of Edinburgh, Royal Observatory, Blackford Hill, Edinburgh EH9 3HJ (United Kingdom)

    2015-01-01

    We discuss the role that dwarf galaxies may have played in the formation of the Galactic halo (Halo) using RR Lyrae stars (RRL) as tracers of their ancient stellar component. The comparison is performed using two observables (periods, luminosity amplitudes) that are reddening and distance independent. Fundamental mode RRL in 6 dwarf spheroidals (dSphs) and 11 ultra faint dwarf galaxies (?1300) show a Gaussian period distribution well peaked around a mean period of (Pab) =0.6100.001days (? = 0.03). The Halo RRL (?15,000) are characterized by a broader period distribution. The fundamental mode RRL in all the dSphs apart from Sagittarius are completely lacking in High Amplitude Short Period (HASP) variables, defined as those having P ?0.48days and A{sub V} ?0.75mag. Such variables are not uncommon in the Halo and among the globular clusters and massive dwarf irregulars. To further interpret this evidence, we considered 18 globulars covering a broad range in metallicity (2.3?[Fe/H]? 1.1) and hosting more than 35 RRL each. The metallicity turns out to be the main parameter, since only globulars more metal-rich than [Fe/H]? 1.5 host RRL in the HASP region. This finding suggests that dSphs similar to the surviving ones do not appear to be the major building-blocks of the Halo. Leading physical arguments suggest an extreme upper limit of ?50% to their contribution. On the other hand, massive dwarfs hosting an old population with a broad metallicity distribution (Large Magellanic Cloud, Sagittarius) may have played a primary role in the formation of the Halo.

  2. ON THE MORPHOLOGY AND CHEMICAL COMPOSITION OF THE HR 4796A DEBRIS DISK

    SciTech Connect (OSTI)

    Rodigas, Timothy J.; Weinberger, Alycia; Stark, Christopher C.; Debes, John H.; Chen, Christine; Hinz, Philip M.; Close, Laird; Smith, Paul S.; Males, Jared R.; Skemer, Andrew J.; Follette, Katherine B.; Morzinski, Katie; Wu, Ya-Lin; Schneider, Glenn; Puglisi, Alfio; Briguglio, Runa; Esposito, Simone; Pinna, Enrico; Riccardi, Armando; Xompero, Marco

    2015-01-10

    We present resolved images of the HR 4796A debris disk using the Magellan adaptive optics system paired with Clio-2 and VisAO. We detect the disk at 0.77 μm, 0.91 μm, 0.99 μm, 2.15 μm, 3.1 μm, 3.3 μm, and 3.8 μm. We find that the deprojected center of the ring is offset from the star by 4.76 ± 1.6 AU and that the deprojected eccentricity is 0.06 ± 0.02, in general agreement with previous studies. We find that the average width of the ring is 14{sub −2}{sup +3}% (11.1{sub −1.6}{sup +2.4} AU), also comparable to previous measurements. Combining our new scattered light data with archival Hubble Space Telescope images at ∼0.5-2 μm, along with previously unpublished Spitzer/MIPS thermal emission data and all other literature thermal data, we set out to constrain the chemical composition of the dust grains. After testing 19 individual root compositions and more than 8400 unique mixtures of these compositions, we find that good fits to the scattered light alone and thermal emission alone are discrepant, suggesting that caution should be exercised if fitting to only one or the other. When we fit to both data sets simultaneously, we find that silicates and organics are generally the most favored, while large abundances of water ice are usually not favored. These results suggest the HR 4796A dust grains are similar to interstellar dust and solar system comets, though improved modeling is necessary to place better constraints on the exact chemical composition of the dust.

  3. CHEMICAL ABUNDANCE ANALYSIS OF A NEUTRON-CAPTURE ENHANCED RED GIANT IN THE BULGE PLAUT FIELD

    SciTech Connect (OSTI)

    Johnson, Christian I.; Rich, R. Michael [Department of Physics and Astronomy, UCLA, 430 Portola Plaza, Box 951547, Los Angeles, CA 90095-1547 (United States)] [Department of Physics and Astronomy, UCLA, 430 Portola Plaza, Box 951547, Los Angeles, CA 90095-1547 (United States); McWilliam, Andrew, E-mail: cijohnson@astro.ucla.edu, E-mail: rmr@astro.ucla.edu, E-mail: cjohnson@cfa.harvard.edu, E-mail: andy@obs.carnegiescience.edu [Observatories of the Carnegie Institution of Washington, Pasadena, CA 91101 (United States)] [Observatories of the Carnegie Institution of Washington, Pasadena, CA 91101 (United States)

    2013-09-20

    We present chemical abundances for 27 elements ranging from oxygen to erbium in the metal-poor ([Fe/H] = 1.67) bulge red giant branch star 2MASS 18174532-3353235. The results are based on equivalent width and spectrum synthesis analyses of a high-resolution (R ? 30, 000) spectrum obtained with the Magellan-MIKE spectrograph. While the light (Z ?< 30) element abundance patterns match those of similar metallicity bulge and halo stars, the strongly enhanced heavy element abundances are more similar to 'r-II' halo stars (e.g., CS 22892-052) typically found at [Fe/H] ?< 2.5. We find that the heaviest elements (Z ? 56) closely follow the scaled-solar r-process abundance pattern. We do not find evidence supporting significant s-process contributions; however, the intermediate mass elements (e.g., Y and Zr) appear to have been produced through a different process than the heaviest elements. The light and heavy element abundance patterns of 2MASS 18174532-3353235 are in good agreement with the more metal-poor r-process enhanced stars CS 22892-052 and BD +17{sup o}3248. 2MASS 18174532-3353235 also shares many chemical characteristics with the similar metallicity but comparatively ?-poor Ursa Minor dwarf galaxy giant COS 82. Interestingly, the Mo and Ru abundances of 2MASS 18174532-3353235 are also strongly enhanced and follow a similar trend recently found to be common in moderately metal-poor main-sequence turn-off halo stars.

  4. Multi-frequency observations of a superbubble in the LMC: The case of LHA 120-N 70

    SciTech Connect (OSTI)

    De Horta, A. Y.; Sommer, E. R.; Filipovi?, M. D.; O'Brien, A.; Bozzetto, L. M.; Collier, J. D.; Wong, G. F.; Crawford, E. J.; Tothill, N. F. H.; Maggi, P.; Haberl, F.

    2014-06-01

    We present a detailed study of new Australia Telescope Compact Array and XMM-Newton observations of LHA 120-N 70 (hereafter N 70), a spherically shaped object in the Large Magellanic Cloud, classified as a superbubble. Both archival and new observations were used to produce high quality radio continuum, X-ray, and optical images. The radio spectral index of N 70 is estimated to be ? = 0.12 0.06, indicating that while a supernova (SN) or supernovae have occurred in the region at some time in the distant past, N 70 is not the remnant of a single specific SN. N 70 exhibits limited polarization with a maximum fractional polarization of 9% in a small area of the northwest limb. We estimate the size of N 70 to have a diameter of 104 pc (1 pc). The morphology of N 70 in X-rays closely follows that in radio and optical, with most X-ray emission confined within the bright shell seen at longer wavelengths. Purely thermal models adequately fit the soft X-ray spectrum which lacks harder emission (above 1 keV). We also examine the pressure output of N 70 where the values for the hot (P {sub X}) and warm (P{sub H} {sub II}) phases are consistent with other studied H II regions. However, the dust-processed radiation pressure (P {sub IR}) is significantly smaller than in any other object studied in Lopez et al. N 70 is a very complex region that is likely to have had multiple factors contributing to both the origin and evolution of the entire region.

  5. A dark energy camera search for missing supergiants in the LMC after the advanced LIGO gravitational-wave event GW150914

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Annis, J.

    2016-05-27

    The collapse of a stellar core is expected to produce gravitational waves (GWs), neutrinos, and in most cases a luminous supernova. Sometimes, however, the optical event could be significantly less luminous than a supernova and a direct collapse to a black hole, where the star just disappears, is possible. The GW event GW150914 was detected by the LIGO Virgo Collaboration via a burst analysis that gave localization contours enclosing the Large Magellanic Cloud (LMC). Shortly thereafter, we used DECam to observe 102 deg2 of the localization area, including 38 deg2 on the LMC for a missing supergiant search. We constructmore » a complete catalog of LMC luminous red supergiants, the best candidates to undergo invisible core collapse, and collected catalogs of other candidates: less luminous red supergiants, yellow supergiants, blue supergiants, luminous blue variable stars, and Wolf–Rayet stars. Of the objects in the imaging region, all are recovered in the images. The timescale for stellar disappearance is set by the free-fall time, which is a function of the stellar radius. Our observations at 4 and 13 days after the event result in a search sensitive to objects of up to about 200 solar radii. We conclude that it is unlikely that GW150914 was caused by the core collapse of a relatively compact supergiant in the LMC, consistent with the LIGO Collaboration analyses of the gravitational waveform as best interpreted as a high mass binary black hole merger. Lastly, we discuss how to generalize this search for future very nearby core-collapse candidates.« less

  6. DETECTION OF WEAK CIRCUMSTELLAR GAS AROUND THE DAZ WHITE DWARF WD 1124-293: EVIDENCE FOR THE ACCRETION OF MULTIPLE ASTEROIDS

    SciTech Connect (OSTI)

    Debes, J. H.; Kilic, M.; Faedi, F.; Shkolnik, E. L.; Lopez-Morales, M.; Weinberger, A. J.; Slesnick, C.; West, R. G.

    2012-07-20

    Single metal-polluted white dwarfs with no dusty disks are believed to be actively accreting metals from a circumstellar disk of gas caused by the destruction of asteroids perturbed by planetary systems. We report, for the first time, the detection of circumstellar Ca II gas in absorption around the DAZ WD 1124-293, which lacks an infrared excess. We constrain the gas to >7 R{sub WD} and <32000 AU, and estimate it to be at {approx}54 R{sub WD}, well within WD 1124-293's tidal disruption radius. This detection is based on several epochs of spectroscopy around the Ca II H and K lines ({lambda} = 3968 A, 3933 A) with the MIKE spectrograph on the Magellan/Clay Telescope at Las Campanas Observatory. We confirm the circumstellar nature of the gas by observing nearby sightlines and finding no evidence for gas from the local interstellar medium. Through archival data we have measured the equivalent width of the two photospheric Ca lines over a period of 11 years. We see <5%-7% epoch-to-epoch variation in equivalent widths over this time period, and no evidence for long term trends. The presence of a circumstellar gas implies a near edge-on inclination to the system, thus we place limits to short period transiting planetary companions with R > R{sub Circled-Plus} using the Wide Angle Search for Planets survey. The presence of gas in orbit around WD 1124-293 implies that most DAZs could harbor planetary systems. Since 25%-30% of white dwarfs show metal line absorption, the dynamical process for perturbing small bodies must be robust.

  7. STRONG CONSTRAINTS TO THE PUTATIVE PLANET CANDIDATE AROUND VB 10 USING DOPPLER SPECTROSCOPY

    SciTech Connect (OSTI)

    Anglada-Escude, Guillem; Shkolnik, Evgenya L.; Weinberger, Alycia J.; Thompson, Ian B.; Osip, David J.; Debes, John H. E-mail: shkolnik@dtm.ciw.edu E-mail: ian@obs.carnegiescience.edu E-mail: john.H.debes@nasa.gov

    2010-03-01

    We present new radial velocity (RV) measurements of the ultra-cool dwarf VB 10, which was recently announced to host a giant planet detected with astrometry. The new observations were obtained using optical spectrographs (MIKE/Magellan and ESPaDOnS/CFHT) and cover 65% of the reported period of 270 days. The nominal precision of the new Doppler measurements is about 150 m s{sup -1} while their standard deviation is 250 m s{sup -1}. However, there are indications that such a larger variation is due to uncontrolled systematic errors. We apply least-squares periodograms to identify the most significant signals and evaluate their false alarm probabilities (FAPs). We show that this method is the proper generalization to astrometric data because (1) it mitigates the coupling of the orbital parameters with the parallax and proper motion, and (2) it permits a direct generalization to include nonlinear Keplerian parameters in a combined fit to astrometry and RV data. Our analysis of the astrometry alone uncovers the reported 270 day period and an even stronger signal at {approx}50 days. We estimate the uncertainties in the parameters using a Markov chain Monte Carlo approach. Although the new data alone cannot rule out the presence of a candidate, when combined with published RV measurements, the FAPs of the best solutions grow to unacceptable levels strongly suggesting that the observed astrometric wobble is not due to an unseen companion. The new measurements put an upper limit of m sin i {approx} 2.5 m {sub jup} for a companion with a period shorter than one year and moderate eccentricities.

  8. A PLANETARY SYSTEM AROUND THE NEARBY M DWARF GJ 667C WITH AT LEAST ONE SUPER-EARTH IN ITS HABITABLE ZONE

    SciTech Connect (OSTI)

    Anglada-Escude, Guillem; Butler, R. Paul; Arriagada, Pamela; Minniti, Dante; Vogt, Steven S.; Rivera, Eugenio J.; Haghighipour, Nader; Carter, Brad D.; Tinney, C. G.; Wittenmyer, Robert A.; Bailey, Jeremy A.; O'Toole, Simon J.; Jones, Hugh R. A.; Jenkins, James S.

    2012-05-20

    We re-analyze 4 years of HARPS spectra of the nearby M1.5 dwarf GJ 667C available through the European Southern Observatory public archive. The new radial velocity (RV) measurements were obtained using a new data analysis technique that derives the Doppler measurement and other instrumental effects using a least-squares approach. Combining these new 143 measurements with 41 additional RVs from the Magellan/Planet Finder Spectrograph and Keck/High Resolution Echelle Spectrometer spectrometers reveals three additional signals beyond the previously reported 7.2 day candidate, with periods of 28 days, 75 days, and a secular trend consistent with the presence of a gas giant (period {approx}10 years). The 28 day signal implies a planet candidate with a minimum mass of 4.5 M{sub Circled-Plus} orbiting well within the canonical definition of the star's liquid water habitable zone (HZ), that is, the region around the star at which an Earth-like planet could sustain liquid water on its surface. Still, the ultimate water supporting capability of this candidate depends on properties that are unknown such as its albedo, atmospheric composition, and interior dynamics. The 75 day signal is less certain, being significantly affected by aliasing interactions among a potential 91 day signal, and the likely rotation period of the star at 105 days detected in two activity indices. GJ 667C is the common proper motion companion to the GJ 667AB binary, which is metal-poor compared to the Sun. The presence of a super-Earth in the HZ of a metal-poor M dwarf in a triple star system supports the evidence that such worlds should be ubiquitous in the Galaxy.

  9. Physical nature of the [S II]-bright shell nebulae N70 and N185

    SciTech Connect (OSTI)

    Zhang, Ning-Xiao; Jiang, Bing; Chen, Yang; Chu, You-Hua; Gruendl, R. A.; Williams, R. M.

    2014-09-01

    N70 and N185 are two large (?100 pc in diameter) shell nebulae in the Large Magellanic Cloud (LMC). Their high [S II]/H? ratios rival those of supernova remnants (SNRs), but they are not confirmed as SNRs. To study their physical nature, we have obtained XMM-Newton X-ray observations and high-dispersion long-slit echelle spectroscopic observations of these two nebulae. The X-ray spectra of both nebulae can be well interpreted with an optically thin thermal (?0.2 keV) plasma with the average LMC abundance in a collisional ionization equilibrium. N70 encompasses the OB association LH114. Although N70 has a modest expansion velocity and essentially thermal radio emission, its diffuse X-ray luminosity (?6.1 10{sup 35} erg s{sup 1}) is higher than that from a quiescent superbubble with N70's density, size, and expansion velocity; thus, N70 is most likely a superbubble that is recently energized by an interior SNR. N185 does not contain any known OB association, and its X-ray luminosity is an order of magnitude lower than expected if it is a quiescent superbubble. N185 has nonthermal radio emission and has high-velocity material expanding at nearly 200 km s{sup 1}, similar to many known SNRs in the LMC. Its X-ray luminosity (?1.9 10{sup 35} erg s{sup 1}) is also consistent with that of an evolved SNR. We therefore suggest that N185 is energized by a recent supernova.

  10. SECULAR EVOLUTION AND A NON-EVOLVING BLACK-HOLE-TO-GALAXY MASS RATIO IN THE LAST 7 Gyr

    SciTech Connect (OSTI)

    Cisternas, Mauricio; Jahnke, Knud; Inskip, Katherine J.; Bongiorno, Angela; Merloni, Andrea; Impey, Chris D.; Koekemoer, Anton M.; Salvato, Mara; Trump, Jonathan R.

    2011-11-01

    We present new constraints on the ratio of black hole (BH) mass to total galaxy stellar mass at 0.3 < z < 0.9 for a sample of 32 type-1 active galactic nuclei (AGNs) from the XMM-COSMOS survey covering the range M{sub BH} {approx} 10{sup 7.2-8.7} M{sub sun}. Virial M{sub BH} estimates based on H{beta} are available from the COSMOS Magellan/IMACS survey. We use high-resolution Hubble Space Telescope (HST) imaging to decompose the light of each type-1 AGN and host galaxy, and employ a specially built mass-to-light ratio to estimate the stellar masses (M{sub *}). The M{sub BH}-M{sub *} ratio shows a zero offset with respect to the local relation for galactic bulge masses, and we also find no evolution in the mass ratio M{sub BH}/M{sub *}{proportional_to}(1 + z){sup 0.02{+-}0.34} up to z {approx} 0.9. Interestingly, at the high-M{sub BH} end there is a positive offset from the z = 0 relation, which can be fully explained by a mass function bias with a cosmic scatter of {sigma}{sub {mu}} = 0.3, reaffirming that the intrinsic distribution is consistent with zero evolution. From our results we conclude that since z {approx} 0.9 no substantial addition of stellar mass is required: the decline in star formation rates and merger activity at z < 1 support this scenario. Nevertheless, given that a significant fraction of these galaxies show a disk component, their bulges are indeed undermassive. This is a direct indication that for the last 7 Gyr the only essential mechanism required for these galaxies to obey the z = 0 relation is a redistribution of stellar mass to the bulge, likely driven by secular processes, i.e., internal instabilities and minor merging.

  11. A NEW CEPHEID DISTANCE TO THE GIANT SPIRAL M101 BASED ON IMAGE SUBTRACTION OF HUBBLE SPACE TELESCOPE/ADVANCED CAMERA FOR SURVEYS OBSERVATIONS

    SciTech Connect (OSTI)

    Shappee, Benjamin J.; Stanek, K. Z. E-mail: kstanek@astronomy.ohio-state.edu

    2011-06-01

    We accurately determine a new Cepheid distance to M101 (NGC 5457) using archival Hubble Space Telescope (HST)/Advanced Camera for Surveys V and I time series photometry of two fields within the galaxy. We make a slight modification to the ISIS image subtraction package to obtain optimal differential light curves from HST data. We discovered 827 Cepheids with periods between 3 and 80 days, the largest extragalactic sample of Cepheids observed with HST by a factor of two. With this large Cepheid sample, we find that the relative distance of M101 from the Large Magellanic Cloud is {Delta}{mu}{sub LMC} = 10.63 {+-} 0.04 (random) {+-} 0.06 (systematic) mag. If we use the geometrically determined maser distance to NGC 4258 as our distance anchor, the distance modulus of M101 is {mu}{sub 0} = 29.04 {+-} 0.05 (random) {+-} 0.18 (systematic) mag or D = 6.4 {+-} 0.2 (random) {+-} 0.5 (systematic) Mpc. The uncertainty is dominated by the maser distance estimate ({+-}0.15 mag), which should improve over the next few years. We determine a steep metallicity dependence, {gamma}, for our Cepheid sample through two methods, yielding {gamma} = -0.80 {+-} 0.21 (random) {+-} 0.06 (systematic) mag dex{sup -1} and {gamma} = -0.72{sup +0.22}{sub -0.25} (random) {+-} 0.06 (systematic) mag dex{sup -1}. We see marginal evidence for variations in the Wesenheit period-luminosity relation slope as a function of deprojected galactocentric radius. We also use the tip of the red giant branch method to independently determine the distance modulus to M101 of {mu}{sub 0} = 29.05 {+-} 0.06 (random) {+-} 0.12 (systematic) mag.

  12. Is the Short Distance Scale a Result of a Problem with the LMC Photometric Zero Point?

    SciTech Connect (OSTI)

    Popowski, P

    2004-03-29

    I present a promising route to harmonize distance measurements based on clump giants and RR Lyrae stars. This is achieved by comparing the brightness of these distance indicators in three environments: the solar neighborhood, Galactic bulge and Large Magellanic Cloud (LMC). As a result of harmonizing the distance scales in the solar neighborhood and Baade's Window, I derive the new absolute magnitude of RR Lyrae stars, M{sub v}(RR) at [Fe/H] = -1.6 (0.59 {+-} 0.05, 0.70 {+-} 0.05). Being somewhat brighter than the statistical parallax solution, but fainter than typical results of the main sequence fitting to Hipparcos data, these values of M{sub V}(RR) favor intermediate or old ages of globular clusters. Harmonizing the distance scales in the LMC and Baade's Window, I show that the most likely distance modulus to the LMC, {mu}{sub LMC} is in the range 18.24 - 18.44. The Hubble constant of about 70 km/s/Mpc reported by the HST Key Project is based on the assumption that the distance modulus to the LMC equals 18.50. The results presented here indicate that the Hubble Constant may be up to 12% higher. This in turn would call for a younger Universe and could result in some tension between the age of the Universe and the ages of globular clusters. I argue that the remaining uncertainty in the distance to the LMC is now a question of one, single photometric reference point rather than discrepancies between different standard candles.

  13. The relationship between stellar mass, gas metallicity, and star formation rate for H?-selected galaxies at z ? 0.8 from the NewH? survey

    SciTech Connect (OSTI)

    Reyes, Mithi A. de los; Ly, Chun; Lee, Janice C.; Peeples, Molly S.; Feddersen, Jesse; Salim, Samir; Momcheva, Ivelina; Dale, Daniel A.; Ouchi, Masami; Ono, Yoshiaki; Finn, Rose

    2015-02-01

    Using a sample of 299 H?-selected galaxies at z?0.8, we study the relationship between galaxy stellar mass, gas-phase metallicity, and star formation rate (SFR), and compare to previous results. We use deep optical spectra obtained with the IMACS spectrograph at the Magellan telescope to measure strong oxygen lines. We combine these spectra and metallicities with (1) rest-frame UV-to-optical imaging, which allows us to determine stellar masses and dust attenuation corrections, and (2) H? narrowband imaging, which provides a robust measurement of the instantaneous SFR. Our sample spans stellar masses of ?10{sup 9}6 10{sup 11} M{sub ?}, SFRs of 0.4270 M{sub ?} yr{sup ?1}, and metal abundances of 12+log(O/H)?8.39.1 (?0.42.6 Z{sub ?}). The correlations that we find between the H?-based SFR and stellar mass (i.e., the star-forming main sequence) and between the stellar mass and metallicity are both consistent with previous z?1 studies of star-forming galaxies. We then study the relationship between the three properties using various plane-fitting techniques and a curve-fitting projection. In all cases, we exclude strong dependence of the M{sub ?}Z relation on SFR, but are unable to distinguish between moderate and no dependence. Our results are consistent with previous massmetallicitySFR studies. We check whether data set limitations may obscure a strong dependence on the SFR by using mock samples drawn from the Sloan Digital Sky Survey. These experiments reveal that the adopted signal-to-noise ratio cuts may have a significant effect on the measured dependence. Further work is needed to investigate these results, and to test whether a fundamental metallicity relation or a fundamental plane describes star-forming galaxies across cosmic time.

  14. DIVERSITY OF TYPE Ia SUPERNOVAE IMPRINTED IN CHEMICAL ABUNDANCES

    SciTech Connect (OSTI)

    Tsujimoto, Takuji [National Astronomical Observatory of Japan, Mitaka-shi, Tokyo 181-8588 (Japan); Shigeyama, Toshikazu, E-mail: taku.tsujimoto@nao.ac.jp [Research Center for the Early Universe, Graduate School of Science, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033 (Japan)

    2012-12-01

    A time delay of Type Ia supernova (SN Ia) explosions hinders the imprint of their nucleosynthesis on stellar abundances. However, some occasional cases give birth to stars that avoid enrichment of their chemical compositions by massive stars and thereby exhibit an SN-Ia-like elemental feature including a very low [Mg/Fe] ( Almost-Equal-To - 1). We highlight the elemental feature of Fe-group elements for two low-Mg/Fe objects detected in nearby galaxies, and propose the presence of a class of SNe Ia that yield the low abundance ratios of [Cr, Mn, Ni/Fe]. Our novel models of chemical evolution reveal that our proposed class of SNe Ia (slow SNe Ia) is associated with ones exploding on a long timescale after their stellar birth and give a significant impact on the chemical enrichment in the Large Magellanic Cloud (LMC). In the Galaxy, on the other hand, this effect is unseen due to the overwhelming enrichment by the major class of SNe Ia that explode promptly (prompt SNe Ia) and eject a large amount of Fe-group elements. This nicely explains the different [Cr, Mn, Ni/Fe] features between the two galaxies as well as the puzzling feature seen in the LMC stars exhibiting very low Ca but normal Mg abundances. Furthermore, the corresponding channel of slow SN Ia is exemplified by performing detailed nucleosynthesis calculations in the scheme of SNe Ia resulting from a 0.8 + 0.6 M{sub Sun} white dwarf merger.

  15. Assessment of Systematic Chromatic Errors that Impact Sub-1% Photometric Precision in Large-Area Sky Surveys

    SciTech Connect (OSTI)

    Li, T.S.; et al.

    2016-01-01

    Meeting the science goals for many current and future ground-based optical large-area sky surveys requires that the calibrated broadband photometry is stable in time and uniform over the sky to 1% precision or better. Past surveys have achieved photometric precision of 1-2% by calibrating the survey's stellar photometry with repeated measurements of a large number of stars observed in multiple epochs. The calibration techniques employed by these surveys only consider the relative frame-by-frame photometric zeropoint offset and the focal plane position-dependent illumination corrections, which are independent of the source color. However, variations in the wavelength dependence of the atmospheric transmission and the instrumental throughput induce source color-dependent systematic errors. These systematic errors must also be considered to achieve the most precise photometric measurements. In this paper, we examine such systematic chromatic errors using photometry from the Dark Energy Survey (DES) as an example. We define a natural magnitude system for DES and calculate the systematic errors on stellar magnitudes, when the atmospheric transmission and instrumental throughput deviate from the natural system. We conclude that the systematic chromatic errors caused by the change of airmass in each exposure, the change of the precipitable water vapor and aerosol in the atmosphere over time, and the non-uniformity of instrumental throughput over the focal plane, can be up to 2% in some bandpasses. We compare the calculated systematic chromatic errors with the observed DES data. For the test sample data, we correct these errors using measurements of the atmospheric transmission and instrumental throughput. The residual after correction is less than 0.3%. We also find that the errors for non-stellar objects are redshift-dependent and can be larger than those for stars at certain redshifts.

  16. Atmospheric Dispersion Effects in Weak Lensing Measurements

    SciTech Connect (OSTI)

    Plazas, Andrés Alejandro; Bernstein, Gary

    2012-10-01

    The wavelength dependence of atmospheric refraction causes elongation of finite-bandwidth images along the elevation vector, which produces spurious signals in weak gravitational lensing shear measurements unless this atmospheric dispersion is calibrated and removed to high precision. Because astrometric solutions and PSF characteristics are typically calibrated from stellar images, differences between the reference stars' spectra and the galaxies' spectra will leave residual errors in both the astrometric positions (dr) and in the second moment (width) of the wavelength-averaged PSF (dv) for galaxies.We estimate the level of dv that will induce spurious weak lensing signals in PSF-corrected galaxy shapes that exceed the statistical errors of the DES and the LSST cosmic-shear experiments. We also estimate the dr signals that will produce unacceptable spurious distortions after stacking of exposures taken at different airmasses and hour angles. We also calculate the errors in the griz bands, and find that dispersion systematics, uncorrected, are up to 6 and 2 times larger in g and r bands,respectively, than the requirements for the DES error budget, but can be safely ignored in i and z bands. For the LSST requirements, the factors are about 30, 10, and 3 in g, r, and i bands,respectively. We find that a simple correction linear in galaxy color is accurate enough to reduce dispersion shear systematics to insignificant levels in the r band for DES and i band for LSST,but still as much as 5 times than the requirements for LSST r-band observations. More complex corrections will likely be able to reduce the systematic cosmic-shear errors below statistical errors for LSST r band. But g-band effects remain large enough that it seems likely that induced systematics will dominate the statistical errors of both surveys, and cosmic-shear measurements should rely on the redder bands.

  17. No Galaxy Left Behind: Accurate Measurements with the Faintest Objects in the Dark Energy Survey

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Suchyta, E.

    2016-01-27

    Accurate statistical measurement with large imaging surveys has traditionally required throwing away a sizable fraction of the data. This is because most measurements have have relied on selecting nearly complete samples, where variations in the composition of the galaxy population with seeing, depth, or other survey characteristics are small. We introduce a new measurement method that aims to minimize this wastage, allowing precision measurement for any class of stars or galaxies detectable in an imaging survey. We have implemented our proposal in Balrog, a software package which embeds fake objects in real imaging in order to accurately characterize measurement biases.more » We also demonstrate this technique with an angular clustering measurement using Dark Energy Survey (DES) data. We first show that recovery of our injected galaxies depends on a wide variety of survey characteristics in the same way as the real data. We then construct a flux-limited sample of the faintest galaxies in DES, chosen specifically for their sensitivity to depth and seeing variations. Using the synthetic galaxies as randoms in the standard LandySzalay correlation function estimator suppresses the effects of variable survey selection by at least two orders of magnitude. Now our measured angular clustering is found to be in excellent agreement with that of a matched sample drawn from much deeper, higherresolution space-based COSMOS imaging; over angular scales of 0.004° < θ < 0.2 ° , we find a best-fit scaling amplitude between the DES and COSMOS measurements of 1.00 ± 0.09. We expect this methodology to be broadly useful for extending the statistical reach of measurements in a wide variety of coming imaging surveys.« less

  18. Atmospheric Dispersion Effects in Weak Lensing Measurements

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Plazas, Andrés Alejandro; Bernstein, Gary

    2012-10-01

    The wavelength dependence of atmospheric refraction causes elongation of finite-bandwidth images along the elevation vector, which produces spurious signals in weak gravitational lensing shear measurements unless this atmospheric dispersion is calibrated and removed to high precision. Because astrometric solutions and PSF characteristics are typically calibrated from stellar images, differences between the reference stars' spectra and the galaxies' spectra will leave residual errors in both the astrometric positions (dr) and in the second moment (width) of the wavelength-averaged PSF (dv) for galaxies.We estimate the level of dv that will induce spurious weak lensing signals in PSF-corrected galaxy shapes that exceed themore » statistical errors of the DES and the LSST cosmic-shear experiments. We also estimate the dr signals that will produce unacceptable spurious distortions after stacking of exposures taken at different airmasses and hour angles. We also calculate the errors in the griz bands, and find that dispersion systematics, uncorrected, are up to 6 and 2 times larger in g and r bands,respectively, than the requirements for the DES error budget, but can be safely ignored in i and z bands. For the LSST requirements, the factors are about 30, 10, and 3 in g, r, and i bands,respectively. We find that a simple correction linear in galaxy color is accurate enough to reduce dispersion shear systematics to insignificant levels in the r band for DES and i band for LSST,but still as much as 5 times than the requirements for LSST r-band observations. More complex corrections will likely be able to reduce the systematic cosmic-shear errors below statistical errors for LSST r band. But g-band effects remain large enough that it seems likely that induced systematics will dominate the statistical errors of both surveys, and cosmic-shear measurements should rely on the redder bands.« less

  19. No Galaxy Left Behind: Accurate Measurements with the Faintest Objects in the Dark Energy Survey

    SciTech Connect (OSTI)

    Suchyta, E.

    2015-07-29

    Accurate statistical measurement with large imaging surveys has traditionally required throwing away a sizable fraction of the data. This is because most measurements have have relied on selecting nearly complete samples, where variations in the composition of the galaxy population with seeing, depth, or other survey characteristics are small. We introduce a new measurement method that aims to minimize this wastage, allowing precision measurement for any class of stars or galaxies detectable in an imaging survey. We have implemented our proposal in Balrog, a software package which embeds fake objects in real imaging in order to accurately characterize measurement biases. We also demonstrate this technique with an angular clustering measurement using Dark Energy Survey (DES) data. We first show that recovery of our injected galaxies depends on a wide variety of survey characteristics in the same way as the real data. We then construct a flux-limited sample of the faintest galaxies in DES, chosen specifically for their sensitivity to depth and seeing variations. Using the synthetic galaxies as randoms in the standard LandySzalay correlation function estimator suppresses the effects of variable survey selection by at least two orders of magnitude. Now our measured angular clustering is found to be in excellent agreement with that of a matched sample drawn from much deeper, higherresolution space-based COSMOS imaging; over angular scales of 0.004° < θ < 0.2 ° , we find a best-fit scaling amplitude between the DES and COSMOS measurements of 1.00 ± 0.09. We expect this methodology to be broadly useful for extending the statistical reach of measurements in a wide variety of coming imaging surveys.

  20. No galaxy left behind. Accurate measurements with the faintest objects in the Dark Energy Survey

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Suchyta, E.; Huff, E. M.; Aleksić, J.; Melchior, P.; Jouvel, S.; MacCrann, N.; Ross, A. J.; Crocce, M.; Gaztanaga, E.; Honscheid, K.; et al

    2016-01-27

    Accurate statistical measurement with large imaging surveys has traditionally required throwing away a sizable fraction of the data. This is because most measurements have relied on selecting nearly complete samples, where variations in the composition of the galaxy population with seeing, depth, or other survey characteristics are small. Here, we introduce a new measurement method that aims to minimize this wastage, allowing precision measurement for any class of detectable stars or galaxies. Moreover, our proposal was implemented in BALROG, software which embeds fake objects in real imaging to accurately characterize measurement biases. We demonstrate this technique with an angular clusteringmore » measurement using Dark Energy Survey (DES) data. We first show that recovery of our injected galaxies depends on a variety of survey characteristics in the same way as the real data. We then construct a flux-limited sample of the faintest galaxies in DES, chosen specifically for their sensitivity to depth and seeing variations. Using the synthetic galaxies as randoms in the Landy–Szalay estimator suppresses the effects of variable survey selection by at least two orders of magnitude. With this correction, our measured angular clustering is found to be in excellent agreement with that of a matched sample from much deeper, higher resolution space-based Cosmological Evolution Survey (COSMOS) imaging; over angular scales of 0.°004 < θ < 0.°2, we find a best-fitting scaling amplitude between the DES and COSMOS measurements of 1.00 ± 0.09. We expect this methodology to be broadly useful for extending measurements’ statistical reach in a variety of upcoming imaging surveys.« less

  1. SUPERNOVA SIMULATIONS AND STRATEGIES FOR THE DARK ENERGY SURVEY

    SciTech Connect (OSTI)

    Bernstein, J. P.; Kuhlmann, S.; Biswas, R.; Kovacs, E.; Crane, I.; Hufford, T.; Kessler, R.; Frieman, J. A.; Aldering, G.; Kim, A. G.; Nugent, P.; D'Andrea, C. B.; Nichol, R. C.; Finley, D. A.; Marriner, J.; Reis, R. R. R.; Jarvis, M. J.; Mukherjee, P.; Parkinson, D.; Sako, M.; and others

    2012-07-10

    We present an analysis of supernova light curves simulated for the upcoming Dark Energy Survey (DES) supernova search. The simulations employ a code suite that generates and fits realistic light curves in order to obtain distance modulus/redshift pairs that are passed to a cosmology fitter. We investigated several different survey strategies including field selection, supernova selection biases, and photometric redshift measurements. Using the results of this study, we chose a 30 deg{sup 2} search area in the griz filter set. We forecast (1) that this survey will provide a homogeneous sample of up to 4000 Type Ia supernovae in the redshift range 0.05 DES camera will significantly improve high-redshift color measurements. The redshift of each supernova with an identified host galaxy will be obtained from spectroscopic observations of the host. A supernova spectrum will be obtained for a subset of the sample, which will be utilized for control studies. In addition, we have investigated the use of combined photometric redshifts taking into account data from both the host and supernova. We have investigated and estimated the likely contamination from core-collapse supernovae based on photometric identification, and have found that a Type Ia supernova sample purity of up to 98% is obtainable given specific assumptions. Furthermore, we present systematic uncertainties due to sample purity, photometric calibration, dust extinction priors, filter-centroid shifts, and inter-calibration. We conclude by estimating the uncertainty on the cosmological parameters that will be measured from the DES supernova data.

  2. Comparative study of microwave radiation-induced magnetoresistive oscillations induced by circularly- and linearly- polarized photo-excitation

    SciTech Connect (OSTI)

    Ye, Tianyu; Liu, Han -Chun; Wang, Zhuo; Wegscheider, W.; Mani, Ramesh G.

    2015-10-09

    A comparative study of the radiation-induced magnetoresistance oscillations in the high mobility GaAs/AlGaAs heterostructure two dimensional electron system (2DES) under linearly- and circularly- polarized microwave excitation indicates a profound difference in the response observed upon rotating the microwave launcher for the two cases, although circularly polarized microwave radiation induced magnetoresistance oscillations observed at low magnetic fields are similar to the oscillations observed with linearly polarized radiation. For the linearly polarized radiation, the magnetoresistive response is a strong sinusoidal function of the launcher rotation (or linear polarization) angle, θ. As a result, for circularly polarized radiation, the oscillatory magnetoresistive response is hardly sensitive to θ.

  3. F.S.V.B. Volleyball

    ScienceCinema (OSTI)

    None

    2011-04-25

    22me assemblée des délégués de la Fédération Suisse de Volley Ball (F.S.V.B.), en présence entre autres de Claude Delay, représentant de la société fédérale de gymnastique et Hans Gauer, représentant de l'association suisse de gymnastique féminine. Annonce d'une démonstration d'un mini match de volley ball à Meyrin dans l'après-midi.

  4. ESMC

    ScienceCinema (OSTI)

    None

    2011-04-25

    Workshops de 2 jours au Cern: 1.partie: communication scientifique: plusieurs discours suivis de questions et intenses discussions: 1.François de Closet "le progrès scientifique" 2.Gerhard Moosleiter(?) exposé avec dias et questions 3.H.Meyers "comment créer de meilleures conditions en communication scientifique 2.partie: science et communication :présentation des dias et questions. Une Russe de Moscou parle entre autre de la situation actuelle de la presse scientifique en Russie 3.partie: conclusions et rapports de la veille de differents groupes de travail 4.partie:questions avec C.Rubbia et N.Calder et remerciements

  5. Summary - SRS Salt Waste Processing Facility

    Office of Environmental Management (EM)

    SRS Co DOE S Proces concen actinid in a se remov adjustm sorben sorben solutio passed separa stream extract sufficie separa (with S vitrifica (DWP Sr/acti federa assure and ha Critica The te (CTE) descrip Readin The Ele Site: S roject: S F Report Date: J ited States Why DOE omposite High Lev Savannah Rive ssing Facility (S ntrate targeted des) from High eries of unit ope ved by contactin ment) with a m nt in a batch m nt (containing S on by cross flow d to a solvent e ated to an aque m. The bulk

  6. L'Aventure du LHC

    ScienceCinema (OSTI)

    None

    2011-10-06

    Cette présentation s?adressera principalement aux personnes qui ont construit le LHC. La construction du LHC fut longue et difficile. De nombreux problèmes sont apparus en cours de route. Tous ont été résolus grâce au dévouement et à l?engagement du personnel et des collaborateurs. Je reviendrai sur les coups durs et les réussites qui ont marqués ces 15 dernières années et je vous montrerai combien cette machine, le fruit de vos efforts, est extraordinaire.

  7. ORISE: Dose Coefficients for Intakes of Radionuclides via Contaminated Wounds

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Dose CoeffiCients for intakes of raDionuCliDes via ContaminateD WounDs R. E. Toohey*, L. Bertelli + , S. L. Sugarman*, A. L. Wiley* and D. M. Christensen* *Radiation Emergency Assistance Center/Training Site, Oak Ridge Institute for Science and Education, Oak Ridge, TN 37031-0117; + Radiation Protection Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545. Ver. 2, Aug 2014 The NCRP Wound Model describing the retention of selected radionuclides at the site of a contaminated

  8. American Socient of Safety Engineers offers Ergonomic Tips for Businesses, Home

    Broader source: Energy.gov [DOE]

    DES PLAINES, IL (March 28, 2002) - With workplace musculoskeletal disorders (MSDs) being the single largest occupational safety and health problem in the U.S. according to the National Institute of Occupational Safety and Health, the American Society of Safety Engineers (ASSE) urges employers to develop and implement now an effective ergonomic system to reduce those injuries. An initial investment in ergonomic programs removes barriers to quality, productivity and human performance by fitting products, tasks, and environments to people and in the long run will save millions later.

  9. List of Authors and Contributors

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    C L S C O N C E P T U A L D E S I G N R E P O R T List of Authors and Contributors J. Arthur, Stanford Synchrotron Radiation Laboratory, Stanford, CA, USA P. Anfinrud, National Institutes of Health, Bethesda, MD, USA P. Audebert, Laboratoire pour l'Utilisation des Lasers, Paris, France K. Bane, Stanford Linear Accelerator Center, Stanford, CA, USA I. Ben-Zvi, Brookhaven National Laboratory, Upton, NY, USA V. Bharadwaj, Stanford Linear Accelerator Center, Stanford, CA, USA R. Bionta, Lawrence

  10. Los Alamos National Laboratory * Est. 1943 The Pulse-Newsletter of the Los Alamos Neutron Science Center and Accelerator Operations and Technology Division

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    1 Los Alamos National Laboratory * Est. 1943 The Pulse-Newsletter of the Los Alamos Neutron Science Center and Accelerator Operations and Technology Division I N S I D E 2 From Alex's Desk 3 lujAn Center reseArCh FeAtureD on Cover oF Langmuir 4 FunCtionAl oxiDes unDer extreme ConDi- tions-quest For new mAteriAls 6 heADs uP! By Diana Del Mauro ADEPS Communications Inside the Lujan Neutron Scattering Center, Victor Fanelli is busy preparing a superconducting magnet. In a series of delicate steps,

  11. Memorial V.J.Glaser

    ScienceCinema (OSTI)

    None

    2011-04-25

    Plusieurs orateurs rendent hommage au grand physicien et scientifique Vladimir Jurko Glaser (1924 - 1984) qui travaillait au Ruder Boscovic Institut à Zagreb avant de venir au Cern en 1957 où il trouvait un poste permanent au département de physique théorique. Walter Tearing, Harry Lehmann,Henry Epstein, Jacques Bros et André Martin font des résumés biographiques de leurs collègue et ami en honorant ses grands qualités d'homme et ses remarquables conquêtes de la science et leurs accomplissement.

  12. Open University

    ScienceCinema (OSTI)

    None

    2011-04-25

    Michel Pentz est née en Afrique du Sud et venu au Cern en 1957 comme physicien et président de l'associaion du personnel. Il est également fondateur du mouvement Antiapartheid de Genève et a participé à la fondation de l'Open University en Grande-Bretagne. Il nous parle des contextes pédagogiques, culturels et nationaux dans lesquels la méthode peut s'appliquer.

  13. Quality Control Inspector: Different Programs, Different Responosibilities

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Quality Control Inspector: Different Programs, Different ResponsibiliDes. A Guide to the JTA So& Skills. Inspects implementaDon of the program. þ þ Documents areas needing improvement in report. þ þ May assure homeowners/clients of follow---up work. ý þ Independent 3 rd party inspectors may be hired by an enDty not in a role to promise follow---up to clients or residents. Agency staff can and should assure clients of proper follow---up when appropriate. May address

  14. Ceremony 25th birthday Cern

    ScienceCinema (OSTI)

    None

    2011-04-25

    Célébration du 25ème anniversaire du Cern (jour par jour) avec discours de L.Van Hove et J.B.Adams, des interludes musicals offerts par Mme Mey et ses collègues (au debut 1.mouvement du quatuor avec piano no 3 de L.van Beethoven) Les directeurs généraux procéderont à la remise du souvenir aux membres de personnel ayant 25 années de service dans l'organisation. Un témoignage de reconnaissance est auss fait à l'interprète Mme Zwerner

  15. Final Report for the Scaled Asynchronous Transfer Mode (ATM) Encryption Laboratory Directed Research and Development Project

    SciTech Connect (OSTI)

    Pierson, L.G.; Witzke, E.L.

    1999-01-01

    This effort studied the integration of innovative methods of key management crypto synchronization, and key agility while scaling encryption speed. Viability of these methods for encryption of ATM cell payloads at the SONET OC- 192 data rate (10 Gb/s), and for operation at OC-48 rates (2.5 Gb/s) was shown. An SNL-Developed pipelined DES design was adapted for the encryption of ATM cells. A proof-of-principle prototype circuit board containing 11 Electronically Programmable Logic Devices (each holding the equivalent of 100,000 gates) was designed, built, and used to prototype a high speed encryptor.

  16. Modeling of dielectric elastomer as electromechanical resonator

    SciTech Connect (OSTI)

    Li, Bo Liu, Lei; Chen, Hualing; Jia, Shuhai; Zhang, Junshi; Li, Dichen

    2014-09-28

    Dielectric elastomers (DEs) feature nonlinear dynamics resulting from an electromechanical coupling. Under alternating voltage, the DE resonates with tunable performances. We present an analysis of the nonlinear dynamics of a DE as electromechanical resonator (DEER) configured as a pure shear actuator. A theoretical model is developed to characterize the complex performance under different boundary conditions. Physical mechanisms are presented and discussed. Chaotic behavior is also predicted, illustrating instabilities in the dynamics. The results provide a guide to the design and application of DEER in haptic devices.

  17. Isolated spinach ribulose-1,5-bisphosphate carboxylase/oxgenase large subunit .epsilon. n-methyltransferase and method of inactivating ribulose-1,5-bishosphatase .epsilon. n-methyltransferase activity

    DOE Patents [OSTI]

    Houtz, Robert L.

    2001-01-01

    The gene sequence for ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco) large subunit (LS) .sup..epsilon. N-methyltansferase (protein methylase III or Rubisco LSMT) from a plant which has a des(methyl) lysyl residue in the LS is disclosed. In addition, the full-length cDNA clones for Rubisco LSMT are disclosed. Transgenic plants and methods of producing same which have the Rubisco LSMT gene inserted into the DNA are also provided. Further, methods of inactivating the enzymatic activity of Rubisco LSMT are also disclosed.

  18. Isolated spinach ribulose-1,5-bisphosphate carboxylase/oxygenase large subunit .sup..epsilon. N-methyltransferase and method of inactivating ribulose-1,5-bisphosphatase carboxylase/oxygenase large subunit .sup..epsilon. N-methyltransferase activity

    DOE Patents [OSTI]

    Houtz, Robert L.

    1999-01-01

    The gene sequence for ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco) large subunit (LS) .sup..epsilon. N-methyltransferase (protein methylase III or Rubisco LSMT) from a plant which has a des(methyl) lysyl residue in the LS is disclosed. In addition, the full-length cDNA clones for Rubisco LSMT are disclosed. Transgenic plants and methods of producing same which have the Rubisco LSMT gene inserted into the DNA are also provided. Further, methods of inactivating the enzymatic activity of Rubisco LSMT are also disclosed.

  19. HA' R$,kAW CH EM I CAL CO,M i=ANY A

    Office of Legacy Management (LM)

    TH Ii ' HA' R$,kAW CH EM I CAL CO,M i=ANY A December 30, 1955 U. S. Atomic Energy Commission Oak Ridge OperationwOfflce Post Office Box "E" Oak Ridge, Tennessee Attention: Mr. T. Carberry Dear Mr. Carberry: ' ..> In the process of removing 'classified documents from the safes at the Main Office for des$ruction we discovered two sample cylinders of hexafluorlde. If memory serves us right these sample6 were prepared at the request of the Commission and shipped to the Unl- versity of

  20. Cooling the dark energy camera instrument

    SciTech Connect (OSTI)

    Schmitt, R.L.; Cease, H.; DePoy, D.; Diehl, H.T.; Estrada, J.; Flaugher, B.; Kuhlmann, S.; Onal, Birce; Stefanik, A.; /Fermilab

    2008-06-01

    DECam, camera for the Dark Energy Survey (DES), is undergoing general design and component testing. For an overview see DePoy, et al in these proceedings. For a description of the imager, see Cease, et al in these proceedings. The CCD instrument will be mounted at the prime focus of the CTIO Blanco 4m telescope. The instrument temperature will be 173K with a heat load of 113W. In similar applications, cooling CCD instruments at the prime focus has been accomplished by three general methods. Liquid nitrogen reservoirs have been constructed to operate in any orientation, pulse tube cryocoolers have been used when tilt angles are limited and Joule-Thompson or Stirling cryocoolers have been used with smaller heat loads. Gifford-MacMahon cooling has been used at the Cassegrain but not at the prime focus. For DES, the combined requirements of high heat load, temperature stability, low vibration, operation in any orientation, liquid nitrogen cost and limited space available led to the design of a pumped, closed loop, circulating nitrogen system. At zenith the instrument will be twelve meters above the pump/cryocooler station. This cooling system expected to have a 10,000 hour maintenance interval. This paper will describe the engineering basis including the thermal model, unbalanced forces, cooldown time, the single and two-phase flow model.

  1. Enhancing Complex System Performance Using Discrete-Event Simulation

    SciTech Connect (OSTI)

    Allgood, Glenn O; Olama, Mohammed M; Lake, Joe E

    2010-01-01

    In this paper, we utilize discrete-event simulation (DES) merged with human factors analysis to provide the venue within which the separation and deconfliction of the system/human operating principles can occur. A concrete example is presented to illustrate the performance enhancement gains for an aviation cargo flow and security inspection system achieved through the development and use of a process DES. The overall performance of the system is computed, analyzed, and optimized for the different system dynamics. Various performance measures are considered such as system capacity, residual capacity, and total number of pallets waiting for inspection in the queue. These metrics are performance indicators of the system's ability to service current needs and respond to additional requests. We studied and analyzed different scenarios by changing various model parameters such as the number of pieces per pallet ratio, number of inspectors and cargo handling personnel, number of forklifts, number and types of detection systems, inspection modality distribution, alarm rate, and cargo closeout time. The increased physical understanding resulting from execution of the queuing model utilizing these vetted performance measures identified effective ways to meet inspection requirements while maintaining or reducing overall operational cost and eliminating any shipping delays associated with any proposed changes in inspection requirements. With this understanding effective operational strategies can be developed to optimally use personnel while still maintaining plant efficiency, reducing process interruptions, and holding or reducing costs.

  2. Automated transient identification in the Dark Energy Survey

    SciTech Connect (OSTI)

    Goldstein, D. A.

    2015-08-20

    We describe an algorithm for identifying point-source transients and moving objects on reference-subtracted optical images containing artifacts of processing and instrumentation. The algorithm makes use of the supervised machine learning technique known as Random Forest. We present results from its use in the Dark Energy Survey Supernova program (DES-SN), where it was trained using a sample of 898,963 signal and background events generated by the transient detection pipeline. After reprocessing the data collected during the first DES-SN observing season (2013 September through 2014 February) using the algorithm, the number of transient candidates eligible for human scanning decreased by a factor of 13.4, while only 1.0 percent of the artificial Type Ia supernovae (SNe) injected into search images to monitor survey efficiency were lost, most of which were very faint events. Here we characterize the algorithm's performance in detail, and we discuss how it can inform pipeline design decisions for future time-domain imaging surveys, such as the Large Synoptic Survey Telescope and the Zwicky Transient Facility.

  3. Automated transient identification in the Dark Energy Survey

    SciTech Connect (OSTI)

    Goldstein, D. A.; D'Andrea, C. B.; Fischer, J. A.; Foley, R. J.; Gupta, R. R.; Kessler, R.; Kim, A. G.; Nichol, R. C.; Nungent, P.; Papadopoulos, A.; Sako, M.; Smith, M.; Sullivan, M.; Thomas, R. C.; Wester, W.; Wolf, R. C.; Abdalla, F. B.; Banjeri, M.; Benoit-Levy, A.; Bertin, E.; Brooks, D.; Rosell, A. Carnero; Castander, F. J.; da Costa, L. N.; Covarrubias, R.; DePoy, D. L.; Desai, S.; Diehl, H. T.; Doel, P.; Eifler, T. F.; Neto, A. Fausti; Finley, D. A.; Flaugher, B.; Fosalba, P.; Frieman, J.; Gerdes, D.; Gruen, D.; Gruendl, R. A.; James, D.; Kuehn, K.; Kuropatkin, N.; Lahav, O.; Li, T. S.; Maia, M. A. G.; Makler, M.; March, M.; Marshall, J. L.; Martini, P.; Merritt, K. W.; Miquel, R.; Nord, B.; Ogando, R.; Plazas, A. A.; Romer, A. K.; Roodman, A.; Sanchez, E.; Scarpine, V.; Schubnell, M.; Sevilla-Noarbe, I.; Smith, R. C.; Soares-Santos, M.; Sobreira, F.; Suchyta, E.; Swanson, M. E. C.; Tarle, G.; Thaler, J.; Walker, A. R.

    2015-09-01

    We describe an algorithm for identifying point-source transients and moving objects on reference-subtracted optical images containing artifacts of processing and instrumentation. The algorithm makes use of the supervised machine learning technique known as Random Forest. We present results from its use in the Dark Energy Survey Supernova program (DES-SN), where it was trained using a sample of 898,963 signal and background events generated by the transient detection pipeline. After reprocessing the data collected during the first DES-SN observing season (2013 September through 2014 February) using the algorithm, the number of transient candidates eligible for human scanning decreased by a factor of 13.4, while only 1.0% of the artificial Type Ia supernovae (SNe) injected into search images to monitor survey efficiency were lost, most of which were very faint events. Furthermore, we characterize the algorithm's performance in detail, and we discuss how it can inform pipeline design decisions for future time-domain imaging surveys, such as the Large Synoptic Survey Telescope and the Zwicky Transient Facility.

  4. Looking Wider and Further: The Evolution of Galaxies Inside Galaxy Clusters

    SciTech Connect (OSTI)

    Zhang, Yuanyuan

    2016-01-01

    Galaxy clusters are rare objects in the universe, but on-going wide field optical surveys are identifying many thousands of them to redshift 1.0 and beyond. Using early data from the Dark Energy Survey (DES) and publicly released data from the Sloan Digital Sky Survey (SDSS), this dissertation explores the evolution of cluster galaxies in the redshift range from 0 to 1.0. As it is common for deep wide field sky surveys like DES to struggle with galaxy detection efficiency at cluster core, the first component of this dissertation describes an efficient package that helps resolving the issue. The second part focuses on the formation of cluster galaxies. The study quantifies the growth of cluster bright central galaxies (BCGs), and argues for the importance of merging and intra-cluster light production during BCG evolution. An analysis of cluster red sequence galaxy luminosity function is also performed, demonstrating that the abundance of these galaxies is mildly dependent on cluster mass and redshift. The last component of the dissertation characterizes the properties of galaxy filaments to help understanding cluster environments

  5. Wide-field lensing mass maps from Dark Energy Survey science verification data: Methodology and detailed analysis

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Vikram, V.

    2015-07-29

    Weak gravitational lensing allows one to reconstruct the spatial distribution of the projected mass density across the sky. These “mass maps” provide a powerful tool for studying cosmology as they probe both luminous and dark matter. In this paper, we present a weak lensing mass map reconstructed from shear measurements in a 139 deg2 area from the Dark Energy Survey (DES) science verification data. We compare the distribution of mass with that of the foreground distribution of galaxies and clusters. The overdensities in the reconstructed map correlate well with the distribution of optically detected clusters. We demonstrate that candidate superclustersmore » and voids along the line of sight can be identified, exploiting the tight scatter of the cluster photometric redshifts. We cross-correlate the mass map with a foreground magnitude-limited galaxy sample from the same data. Our measurement gives results consistent with mock catalogs from N-body simulations that include the primary sources of statistical uncertainties in the galaxy, lensing, and photo-z catalogs. The statistical significance of the cross-correlation is at the 6.8σ level with 20 arcminute smoothing. We find that the contribution of systematics to the lensing mass maps is generally within measurement uncertainties. In this study, we analyze less than 3% of the final area that will be mapped by the DES; the tools and analysis techniques developed in this paper can be applied to forthcoming larger data sets from the survey.« less

  6. TIDAL INTERACTION AS THE ORIGIN OF EARLY-TYPE DWARF GALAXIES IN GROUP ENVIRONMENTS

    SciTech Connect (OSTI)

    Paudel, Sanjaya; Ree, Chang H.

    2014-11-20

    We present a sample of dwarf galaxies that suffer ongoing disruption by the tidal forces of nearby massive galaxies. By analyzing structural and stellar population properties using the archival imaging and spectroscopic data from the Sloan Digital Sky Survey (SDSS), we find that they are likely a ''smoking gun'' example of the formation through tidal stirring of early-type dwarf galaxies (dEs) in the galaxy group environment. The inner cores of these galaxies are fairly intact and the observed light profiles are well fit by the Srsic functions while the tidally stretched stellar halos are prominent in the outer parts. They are all located within a sky-projected distance of 50 kpc from the centers of the host galaxies and no dwarf galaxies have relative line-of-sight velocities larger than 205 km s{sup 1} to their hosts. We derive the Composite Stellar Population properties of these galaxies by fitting the SDSS optical spectra to a multiple-burst composite stellar population model. We find that these galaxies accumulate a significant fraction of stellar mass within the last 1 Gyr and contain a majority stellar population with an intermediate age of 2 to 4 Gyr. Based on this evidence, we argue that tidal stirring, particularly through the galaxy-galaxy interaction, might have an important role in the formation and evolution of dEs in the group environment where the influence of other gas stripping mechanism might be limited.

  7. Spreading of lithium on a stainless steel surface at room temperature

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Skinner, C. H.; Capece, A. M.; Roszell, J. P.; Koel, B. E.

    2016-01-01

    Lithium conditioned plasma facing surfaces have lowered recycling and enhanced plasma performance on many fusion devices and liquid lithium plasma facing components are under consideration for future machines. A key factor in the performance of liquid lithium components is the wetting by lithium of its container. We have observed the surface spreading of lithium from a mm-scale particle to adjacent stainless steel surfaces using a scanning Auger microprobe that has elemental discrimination. The spreading of lithium occurred at room temperature (when lithium is a solid) from one location at a speed of 0.62 mu m/day under ultrahigh vacuum conditions. Separatemore » experiments using temperature programmed desorption (TPD) investigated bonding energetics between monolayer-scale films of lithium and stainless steel. While multilayer lithium desorption from stainless steel begins to occur just above 500 K (E-des = 1.54 eV), sub-monolayer Li desorption occurred in a TPD peak at 942 K (E-des = 2.52 eV) indicating more energetically favorable lithium-stainless steel bonding (in the absence of an oxidation layer) than lithium lithium bonding. (C) 2015 Elsevier B.V. All rights reserved.« less

  8. Influence of the support of CoMo sulfide catalysts and of the addition of potassium and platinum on the catalytic performances for the hydrodeoxygenation of carbonyl, carboxyl, and guaiacol-type molecules

    SciTech Connect (OSTI)

    Centeno, A.; Laurent, E.; Delmon, B. [Universite Catholique de Louvain, Louvain-la-Neuve (Belgium)] [Universite Catholique de Louvain, Louvain-la-Neuve (Belgium)

    1995-07-01

    The present work corresponds to part of a program aimed at upgrading oil obtained by pyrolysis of biomass by hydrotreatment (hydrodeoxygenation HDO). CoMo sulfide catalysts, nonsupported, supported on different supports (alumina, carbon, silica), or modified by K or Pt, were used. The authors used a model reacting mixture containing compounds representative of the molecules that must react to permit a primary stabilisation of the pyrolytic oil: 4-methy lacetophenone (4-MA), diethylsebacate (DES), and guaiacol (GUA). In the reaction of the carbonyl group of the 4-MA it is shown that no important role is played by any acid-base mechanism; dispersion determines the activity. Acidity of the support influences the formation of active sites for decarboxylation and hydrogenation of the carboxyl group of DES. It was confirmed that guaiacol-type molecules lead to coking reactions. The role of acidity in the mechanism of these reactions is confirmed, but the modifications made in the catalysts in this work are still not sufficient to control coke deposition. The catalysts supported on carbon lead to the direct elimination of the methoxyl group of the guaiacol. Carbon, on the whole, seems to be a promising support. This work suggests that appropriate modifications of the hydrotreating catalysts can lead to a more effective process for stabilisation of the bio-oils by reaction with hydrogen. 55 refs., 3 figs., 5 tabs.

  9. Spreading of lithium on a stainless steel surface at room temperature

    SciTech Connect (OSTI)

    Skinner, C. H.; Capece, A. M.; Roszell, J. P.; Koel, B. E.

    2016-01-01

    Lithium conditioned plasma facing surfaces have lowered recycling and enhanced plasma performance on many fusion devices and liquid lithium plasma facing components are under consideration for future machines. A key factor in the performance of liquid lithium components is the wetting by lithium of its container. We have observed the surface spreading of lithium from a mm-scale particle to adjacent stainless steel surfaces using a scanning Auger microprobe that has elemental discrimination. The spreading of lithium occurred at room temperature (when lithium is a solid) from one location at a speed of 0.62 mu m/day under ultrahigh vacuum conditions. Separate experiments using temperature programmed desorption (TPD) investigated bonding energetics between monolayer-scale films of lithium and stainless steel. While multilayer lithium desorption from stainless steel begins to occur just above 500 K (E-des = 1.54 eV), sub-monolayer Li desorption occurred in a TPD peak at 942 K (E-des = 2.52 eV) indicating more energetically favorable lithium-stainless steel bonding (in the absence of an oxidation layer) than lithium lithium bonding. (C) 2015 Elsevier B.V. All rights reserved.

  10. Crowdsourcing quality control for Dark Energy Survey images

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Melchior, P.

    2016-07-01

    We have developed a crowdsourcing web application for image quality controlemployed by the Dark Energy Survey. Dubbed the "DES exposure checker", itrenders science-grade images directly to a web browser and allows users to markproblematic features from a set of predefined classes. Users can also generatecustom labels and thus help identify previously unknown problem classes. Userreports are fed back to hardware and software experts to help mitigate andeliminate recognized issues. We report on the implementation of the applicationand our experience with its over 100 users, the majority of which areprofessional or prospective astronomers but not data management experts. Wediscuss aspects ofmore » user training and engagement, and demonstrate how problemreports have been pivotal to rapidly correct artifacts which would likely havebeen too subtle or infrequent to be recognized otherwise. We conclude with anumber of important lessons learned, suggest possible improvements, andrecommend this collective exploratory approach for future astronomical surveysor other extensive data sets with a sufficiently large user base. We alsorelease open-source code of the web application and host an online demo versionat http://des-exp-checker.pmelchior.net« less

  11. Automated transient identification in the Dark Energy Survey

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Goldstein, D. A.; D'Andrea, C. B.; Fischer, J. A.; Foley, R. J.; Gupta, R. R.; Kessler, R.; Kim, A. G.; Nichol, R. C.; Nungent, P.; Papadopoulos, A.; et al

    2015-09-01

    We describe an algorithm for identifying point-source transients and moving objects on reference-subtracted optical images containing artifacts of processing and instrumentation. The algorithm makes use of the supervised machine learning technique known as Random Forest. We present results from its use in the Dark Energy Survey Supernova program (DES-SN), where it was trained using a sample of 898,963 signal and background events generated by the transient detection pipeline. After reprocessing the data collected during the first DES-SN observing season (2013 September through 2014 February) using the algorithm, the number of transient candidates eligible for human scanning decreased by a factormore » of 13.4, while only 1.0% of the artificial Type Ia supernovae (SNe) injected into search images to monitor survey efficiency were lost, most of which were very faint events. Furthermore, we characterize the algorithm's performance in detail, and we discuss how it can inform pipeline design decisions for future time-domain imaging surveys, such as the Large Synoptic Survey Telescope and the Zwicky Transient Facility.« less

  12. Pennsylvanian and Permian paleogeography of south-central Idaho: The Wood River basin

    SciTech Connect (OSTI)

    Mahoney, J.B. ); Burton, B.R. ); O'Brien, J.P.; Link, P.K. )

    1991-02-01

    The Sun Valley Assemblage (Wood River, Dollarhide, and Grand Prize formations) was deposited in the Wood Rover basin in what is now south-central Idaho, north of the Snake River Plain, from the Atokan to Wolfcampian and Leonardian( ). Atokan and Des Moinesian deposition occurred in braided deltas and overlying clear water carbonate shoals. The rocks of this depositional system vary in thickness from tens to several hundreds of meters reflecting irregularities in the erosional surface on the underlying foundered Antler highland. This basal unconformity has been sheared during Mesozoic and Paleogene deformation. Significant regional subsidence of the Wood River basin began in the Des Moinesian, was most rapid in the Virgilian, and slowed in the Wolfcampian, resulting in total thickness of over 2,000 m for each of the three formations. In the central part of the basin (Wood River Formation) a sub-wave-base ramp system with southeastern paleoslope was fed by turbidite flows of mixed carbonate-siliciclastic fine-grained sediment that had been thoroughly mixed on a shelf area to the north and east. The carbonate fraction may have been derived from the Snaky Canyon Formation carbonate platform to the east. To the north, a siliciclastic fan or ramp system (Grand Prize Formation) was present. Virgilian and Wolfcampian strata represent highstand systems tracts and a lowstand tract is present in strata deposited near the Virgilian-Wolfcampian boundary.

  13. Discovery of a Stellar Overdensity in Eridanus-Phoenix in the Dark Energy Survey

    SciTech Connect (OSTI)

    Li, T.S.; et al.

    2015-09-14

    We report the discovery of an excess of main sequence turn-off stars in the direction of the constellations of Eridanus and Phoenix from the first year data of the Dark Energy Survey (DES). The Eridanus-Phoenix (EriPhe) overdensity is centered around l~285 deg and b~-60 deg and spans at least 30 deg in longitude and 10 deg in latitude. The Poisson significance of the detection is at least 9 sigma. The stellar population in the overdense region is similar in brightness and color to that of the nearby globular cluster NGC 1261, indicating that the heliocentric distance of EriPhe is about d~16 kpc. The extent of EriPhe in projection is therefore at least ~4 kpc by ~3 kpc. On the sky, this overdensity is located between NGC 1261 and a new stellar stream discovered by DES at a similar heliocentric distance, the so-called Phoenix Stream. Given their similar distance and proximity to each other, it is possible that these three structures may be kinematically associated. Alternatively, the EriPhe overdensity is morphologically similar to the Virgo overdensity and the Hercules-Aquila cloud, which also lie at a similar Galactocentric distance. These three overdensities lie along a polar plane separated by ~120 deg and may share a common origin. Spectroscopic follow-up observations of the stars in EriPhe are required to fully understand the nature of this overdensity.

  14. Wide-field lensing mass maps from Dark Energy Survey science verification data: Methodology and detailed analysis

    SciTech Connect (OSTI)

    Vikram, V.

    2015-07-29

    Weak gravitational lensing allows one to reconstruct the spatial distribution of the projected mass density across the sky. These mass maps provide a powerful tool for studying cosmology as they probe both luminous and dark matter. In this paper, we present a weak lensing mass map reconstructed from shear measurements in a 139 deg2 area from the Dark Energy Survey (DES) science verification data. We compare the distribution of mass with that of the foreground distribution of galaxies and clusters. The overdensities in the reconstructed map correlate well with the distribution of optically detected clusters. We demonstrate that candidate superclusters and voids along the line of sight can be identified, exploiting the tight scatter of the cluster photometric redshifts. We cross-correlate the mass map with a foreground magnitude-limited galaxy sample from the same data. Our measurement gives results consistent with mock catalogs from N-body simulations that include the primary sources of statistical uncertainties in the galaxy, lensing, and photo-z catalogs. The statistical significance of the cross-correlation is at the 6.8? level with 20 arcminute smoothing. We find that the contribution of systematics to the lensing mass maps is generally within measurement uncertainties. In this study, we analyze less than 3% of the final area that will be mapped by the DES; the tools and analysis techniques developed in this paper can be applied to forthcoming larger data sets from the survey.

  15. Discovery of a stellar overdensity in Eridanus-Phoenix in the dark energy survey

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Li, T. S.; Balbinot, E.; Mondrik, N.; Marshall, J. L.; Yanny, B.; Bechtol, K.; Drlica-Wagner, A.; Oscar, D.; Santiago, B.; Simon, J. D.; et al

    2016-01-27

    We report the discovery of an excess of main sequence turn-off stars in the direction of the constellations of Eridanus and Phoenix from the first year data of the Dark Energy Survey (DES). The Eridanus-Phoenix (EriPhe) overdensity is centered around l~285 deg and b~-60 deg and spans at least 30 deg in longitude and 10 deg in latitude. The Poisson significance of the detection is at least 9 sigma. The stellar population in the overdense region is similar in brightness and color to that of the nearby globular cluster NGC 1261, indicating that the heliocentric distance of EriPhe is aboutmore » d~16 kpc. The extent of EriPhe in projection is therefore at least ~4 kpc by ~3 kpc. On the sky, this overdensity is located between NGC 1261 and a new stellar stream discovered by DES at a similar heliocentric distance, the so-called Phoenix Stream. Given their similar distance and proximity to each other, it is possible that these three structures may be kinematically associated. Alternatively, the EriPhe overdensity is morphologically similar to the Virgo overdensity and the Hercules-Aquila cloud, which also lie at a similar Galactocentric distance. These three overdensities lie along a polar plane separated by ~120 deg and may share a common origin. Spectroscopic follow-up observations of the stars in EriPhe are required to fully understand the nature of this overdensity.« less

  16. The Dark Energy Survey Camera (DECam)

    SciTech Connect (OSTI)

    Diehl, H.Thomas; /Fermilab

    2011-09-09

    The Dark Energy Survey (DES) is a next generation optical survey aimed at understanding the expansion rate of the Universe using four complementary methods: weak gravitational lensing, galaxy cluster counts, baryon acoustic oscillations, and Type Ia supernovae. To perform the survey, the DES Collaboration is building the Dark Energy Camera (DECam), a 3 square degree, 570 Megapixel CCD camera that will be mounted at the prime focus of the Blanco 4-meter telescope at the Cerro Tololo Inter-American Observatory. CCD production has finished, yielding roughly twice the required 62 2k x 4k detectors. The construction of DECam is nearly finished. Integration and commissioning on a 'telescope simulator' of the major hardware and software components, except for the optics, recently concluded at Fermilab. Final assembly of the optical corrector has started at University College, London. Some components have already been received at CTIO. 'First-light' will be sometime in 2012. This oral presentation concentrates on the technical challenges involved in building DECam (and how we overcame them), and the present status of the instrument.

  17. ABUNDANCES OF C, N, Sr, AND Ba ON THE RED GIANT BRANCH OF {omega} CENTAURI

    SciTech Connect (OSTI)

    Stanford, Laura M.; Da Costa, G. S.; Norris, John E. E-mail: gdc@mso.anu.edu.a

    2010-05-10

    Abundances relative to iron for carbon, nitrogen, strontium, and barium are presented for 33 stars on the red giant branch (RGB) of the globular cluster {omega} Centauri. They are based on intermediate-resolution spectroscopic data covering the blue spectral region analyzed using spectrum synthesis techniques. The data reveal the existence of a broad range in the abundances of these elements, and a comparison with similar data for main-sequence stars enables insight into the evolutionary history of the cluster. The majority of the RGB stars were found to be depleted in carbon, i.e., [C/Fe] < 0, while [N/Fe] for the same stars shows a range of {approx}1 dex, from [N/Fe] {approx} 0.7 to 1.7 dex. The strontium-to-iron abundance ratios varied from solar to mildly enhanced (0.0 {<=} [Sr/Fe] {<=} 0.8), with [Ba/Fe] generally equal to or greater than [Sr/Fe]. The carbon and nitrogen abundance ratios for the one known CH star in the sample, ROA 279, are [C/Fe] = 0.6 and [N/Fe] = 0.5 dex. Evidence for evolutionary mixing on the RGB is found from the fact that the relative carbon abundances on the main sequence are generally higher than those on the RGB. However, comparison of the RGB and main-sequence samples shows that the upper level of nitrogen enhancement is similar in both sets at [N/Fe] {approx} 2.0 dex. This is most likely the result of primordial rather than evolutionary mixing processes. One RGB star, ROA 276, was found to have Sr and Ba abundance ratios similar to the anomalous Sr-rich main-sequence star S2015448. High-resolution spectra of ROA 276 were obtained with the Magellan Telescope/MIKE spectrograph combination to confirm this result, revealing that ROA 276 is indeed an unusual star. For this star, calculations of the depletion effect, the potential change in surface abundance that results from the increased depth of the convective envelope as a star moves from the main sequence to the RGB, strongly suggest that the observed Sr enhancement in ROA 276 is of

  18. HD/H{sub 2} AS A PROBE OF THE ROLES OF GAS, DUST, LIGHT, METALLICITY, AND COSMIC RAYS IN PROMOTING THE GROWTH OF MOLECULAR HYDROGEN IN THE DIFFUSE INTERSTELLAR MEDIUM

    SciTech Connect (OSTI)

    Liszt, H. S.

    2015-01-20

    We modeled recent observations of UV absorption of HD and H{sub 2} in the Milky Way and toward damped/subdamped Lyα systems at z = 0.18 and z >1.7. N(HD)/N(H{sub 2}) ratios reflect the separate self-shieldings of HD and H{sub 2} and the coupling introduced by deuteration chemistry. Locally, observations are explained by diffuse molecular gas with 16 cm{sup –3} ≲ n(H) ≲ 128 cm{sup –3} if the cosmic-ray ionization rate per H nucleus ζ {sub H} =2 × 10{sup –16} s{sup –1}, as inferred from H{sub 3} {sup +} and OH{sup +}. The dominant influence on N(HD)/N(H{sub 2}) is the cosmic-ray ionization rate with a much weaker downward dependence on n(H) at solar metallicity, but dust extinction can drive N(HD) higher as with N(H{sub 2}). At z > 1.7, N(HD) is comparable to the Galaxy but with 10 times smaller N(H{sub 2}) and somewhat smaller N(H{sub 2})/N(H I). Comparison of our Galaxy with the Magellanic Clouds shows that smaller H{sub 2}/H is expected at subsolar metallicity, and we show by modeling that HD/H{sub 2} increases with density at low metallicity, opposite to the Milky Way. Observations of HD would be explained with higher n(H) at low metallicity, but high-z systems have high HD/H{sub 2} at metallicity 0.04 ≲ Z ≲ 2 solar. In parallel, we trace dust extinction and self-shielding effects. The abrupt H{sub 2} transition to H{sub 2}/H ≈ 1%-10% occurs mostly from self-shielding, although it is assisted by extinction for n(H) ≲ 16 cm{sup –3}. Interior H{sub 2} fractions are substantially increased by dust extinction below ≲ 32 cm{sup –3}. At smaller n(H), ζ {sub H}, small increases in H{sub 2} triggered by dust extinction can trigger abrupt increases in N(HD)

  19. STAR FORMATION AND DUST OBSCURATION IN THE TIDALLY DISTORTED GALAXY NGC 2442

    SciTech Connect (OSTI)

    Pancoast, Anna; Sajina, Anna; Lacy, Mark; Noriega-Crespo, Alberto; Rho, Jeonghee

    2010-11-01

    We present a detailed investigation of the morphological distribution and level of star formation and dust obscuration in the nearby tidally distorted galaxy NGC 2442. Spitzer images in the IR at 3.6, 4.5, 5.8, 8.0, and 24 {mu}m and GALEX images at 1500 A and 2300 A allow us to resolve the galaxy on scales between {approx}240 and 600 pc. We supplement these with archival data in the B, J, H, and K bands. We use the 8 {mu}m, 24 {mu}m, and FUV (1500 A) emission to study the star formation rate (SFR). We find that, globally, these tracers of star formation give a range of results of {approx}6-11 M{sub sun} yr{sup -1}, with the dust-corrected FUV giving the highest value of SFR. We can reconcile the UV- and IR-based estimates by adopting a steeper UV extinction curve that lies in between the starburst (Calzetti) and Small Magellanic Cloud extinction curves. However, the regions of the highest SFR intensity along the spiral arms are consistent with a starburst-like extinction. Overall, the level of star formation we find is higher than previously published for this galaxy, by about a factor of 2, which, contrary to previous conclusions, implies that the interaction that caused the distorted morphology of NGC 2442 likely also triggered increased levels of star formation activity. We also find marked asymmetry in that the north spiral arm has a noticeably higher SFR than the southern arm. The tip of the southern spiral arm shows a likely tidally distorted peculiar morphology. It is UV bright and shows unusual IRAC colors, consistent with other published tidal features IRAC data. Outside of the spiral arms, we discover what appears to be a superbubble, {approx}1.7 kpc across, which is seen most clearly in the IRAC images. Significant H{alpha}, UV, and IR emission in the area also suggest vigorous ongoing star formation. A known, recent supernova (SN 1999ga) is located at the edge of this superbubble. Although speculative at this stage, this area suggests a large star

  20. Detailed abundances of planet-hosting wide binaries. I. Did planet formation imprint chemical signatures in the atmospheres of HD 20782/81?

    SciTech Connect (OSTI)

    Mack III, Claude E.; Stassun, Keivan G.; Schuler, Simon C.; Norris, John

    2014-06-01

    Using high-resolution, high signal-to-noise echelle spectra obtained with Magellan/MIKE, we present a detailed chemical abundance analysis of both stars in the planet-hosting wide binary system HD 20782 + HD 20781. Both stars are G dwarfs, and presumably coeval, forming in the same molecular cloud. Therefore we expect that they should possess the same bulk metallicities. Furthermore, both stars also host giant planets on eccentric orbits with pericenters ≲0.2 AU. Here, we investigate if planets with such orbits could lead to the host stars ingesting material, which in turn may leave similar chemical imprints in their atmospheric abundances. We derived abundances of 15 elements spanning a range of condensation temperature, T {sub C} ≈ 40-1660 K. The two stars are found to have a mean element-to-element abundance difference of 0.04 ± 0.07 dex, which is consistent with both stars having identical bulk metallicities. In addition, for both stars, the refractory elements (T {sub C} >900 K) exhibit a positive correlation between abundance (relative to solar) and T {sub C}, with similar slopes of ≈1×10{sup –4} dex K{sup –1}. The measured positive correlations are not perfect; both stars exhibit a scatter of ≈5×10{sup –5} dex K{sup –1} about the mean trend, and certain elements (Na, Al, Sc) are similarly deviant in both stars. These findings are discussed in the context of models for giant planet migration that predict the accretion of H-depleted rocky material by the host star. We show that a simple simulation of a solar-type star accreting material with Earth-like composition predicts a positive—but imperfect—correlation between refractory elemental abundances and T {sub C}. Our measured slopes are consistent with what is predicted for the ingestion of 10-20 Earths by each star in the system. In addition, the specific element-by-element scatter might be used to distinguish between planetary accretion and Galactic chemical evolution scenarios.

  1. MOSFIRE and LDSS3 spectroscopy for an [O II] Blob at z = 1.18: gas outflow and energy source

    SciTech Connect (OSTI)

    Harikane, Yuichi; Ouchi, Masami; Yuma, Suraphong; Ono, Yoshiaki; Rauch, Michael; Nakajima, Kimihiko

    2014-10-20

    We report our Keck/MOSFIRE and Magellan/Low-Dispersion Survey Spectrograph spectroscopy for an [O II] Blob, O II B 10, that is a high-z galaxy with spatially extended [O II] λλ3726, 3729 emission over 30 kpc recently identified by a Subaru large-area narrowband survey. The systemic redshift of O II B 10 is z = 1.18 securely determined with [O III] λλ4959, 5007 and Hβ emission lines. We identify Fe II λ2587 and Mg II λλ2796, 2804 absorption lines blueshifted from the systemic redshift by 80 ± 50 and 260 ± 40 km s{sup –1}, respectively, which indicates gas outflow from O II B 10 with the velocity of ∼80-260 km s{sup –1}. This outflow velocity is comparable with the escape velocity, 250 ± 140 km s{sup –1}, estimated under the assumption of a singular isothermal halo potential profile. Some fraction of the outflowing gas could escape from the halo of O II B 10, suppressing O II B 10's star-formation (SF) activity. We estimate a mass loading factor, η, that is a ratio of mass outflow rate to SF rate, and obtain η > 0.8 ± 0.1, which is relatively high compared with low-z starbursts including U/LIRGs and active galactic nuclei (AGNs). The major energy source of the outflow is unclear with the available data. Although no signature of AGNs is found in the X-ray data, O II B 10 falls in the AGN/star-forming composite region in the line diagnostic diagrams. It is possible that the outflow is powered by SF and a type-2 AGN with narrow FWHM emission line widths of 70-130 km s{sup –1}. This is the first detailed spectroscopic study of oxygen-line blobs that includes analyses of the escape velocity, the mass loading factor, and the presence of an AGN, and is a significant step to understanding the nature of oxygen-line blobs and the relation between gas outflow and SF quenching at high redshift.

  2. THE RELATION BETWEEN STAR FORMATION RATE AND STELLAR MASS FOR GALAXIES AT 3.5 ≤ z ≤ 6.5 IN CANDELS

    SciTech Connect (OSTI)

    Salmon, Brett; Papovich, Casey; Tilvi, Vithal; Finkelstein, Steven L.; Finlator, Kristian; Behroozi, Peter; Lu, Yu; Wechsler, Risa H.; Dahlen, Tomas; Ferguson, Henry C.; Davé, Romeel; Dekel, Avishai; Dickinson, Mark; Giavalisco, Mauro; Long, James; Mobasher, Bahram; Reddy, Naveen; Somerville, Rachel S.

    2015-02-01

    Distant star-forming galaxies show a correlation between their star formation rates (SFRs) and stellar masses, and this has deep implications for galaxy formation. Here, we present a study on the evolution of the slope and scatter of the SFR-stellar mass relation for galaxies at 3.5 ≤ z ≤ 6.5 using multi-wavelength photometry in GOODS-S from the Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey (CANDELS) and Spitzer Extended Deep Survey. We describe an updated, Bayesian spectral-energy distribution fitting method that incorporates effects of nebular line emission, star formation histories that are constant or rising with time, and different dust-attenuation prescriptions (starburst and Small Magellanic Cloud). From z = 6.5 to z = 3.5 star-forming galaxies in CANDELS follow a nearly unevolving correlation between stellar mass and SFR that follows SFR ∼ M{sub ⋆}{sup a} with a =0.54 ± 0.16 at z ∼ 6 and 0.70 ± 0.21 at z ∼ 4. This evolution requires a star formation history that increases with decreasing redshift (on average, the SFRs of individual galaxies rise with time). The observed scatter in the SFR-stellar mass relation is tight, σ(log SFR/M {sub ☉} yr{sup –1}) < 0.3-0.4 dex, for galaxies with log M {sub *}/M {sub ☉} > 9 dex. Assuming that the SFR is tied to the net gas inflow rate (SFR ∼ M-dot {sub gas}), then the scatter in the gas inflow rate is also smaller than 0.3–0.4 dex for star-forming galaxies in these stellar mass and redshift ranges, at least when averaged over the timescale of star formation. We further show that the implied star formation history of objects selected on the basis of their co-moving number densities is consistent with the evolution in the SFR-stellar mass relation.

  3. Diffuse interstellar bands versus known atomic and molecular species in the interstellar medium of M82 toward SN 2014J

    SciTech Connect (OSTI)

    Welty, Daniel E.; York, Donald G. [Department of Astronomy and Astrophysics, University of Chicago, 5640 South Ellis Avenue, Chicago, IL 60637 (United States); Ritchey, Adam M. [Department of Astronomy, University of Washington, Box 351580, Seattle, WA 98195 (United States); Dahlstrom, Julie A., E-mail: dwelty@oddjob.uchicago.edu [Department of Physics and Astronomy, Carthage College, 2001 Alford Park Drive, Kenosha, WI 53140 (United States)

    2014-09-10

    We discuss the absorption due to various constituents of the interstellar medium (ISM) of M82 seen in moderately high-resolution, high signal-to-noise ratio optical spectra of SN 2014J. Complex absorption from M82 is seen, at velocities 45 ? v {sub LSR} ? 260 km s{sup 1}, for Na I, K I, Ca I, Ca II, CH, CH{sup +}, and CN; many of the diffuse interstellar bands (DIBs) are also detected. Comparisons of the column densities of the atomic and molecular species and the equivalent widths of the DIBs reveal both similarities and differences in relative abundances, compared to trends seen in the ISM of our Galaxy and the Magellanic Clouds. Of the 10 relatively strong DIBs considered here, 6 (including ?5780.5) have strengths within 20% of the mean values seen in the local Galactic ISM, for comparable N(K I); 2 are weaker by 20%-45% and 2 (including ?5797.1) are stronger by 25%-40%. Weaker than 'expected' DIBs (relative to N(K I), N(Na I), and E(B V)) in some Galactic sight lines and toward several other extragalactic supernovae appear to be associated with strong CN absorption and/or significant molecular fractions. While the N(CH)/N(K I) and N(CN)/N(CH) ratios seen toward SN 2014J are similar to those found in the local Galactic ISM, the combination of high N(CH{sup +})/N(CH) and high W(5797.1)/W(5780.5) ratios has not been seen elsewhere. The centroids of many of the M82 DIBs are shifted relative to the envelope of the K I profilelikely due to component-to-component variations in W(DIB)/N(K I) that may reflect the molecular content of the individual components. We compare estimates for the host galaxy reddening E(B V) and visual extinction A {sub V} derived from the various interstellar species with the values estimated from optical and near-IR photometry of SN 2014J.

  4. Parametric Model for Astrophysical Proton-Proton Interactions and Applications

    SciTech Connect (OSTI)

    Karlsson, Niklas; ,

    2008-01-29

    Observations of gamma-rays have been made from celestial sources such as active galaxies, gamma-ray bursts and supernova remnants as well as the Galactic ridge. The study of gamma rays can provide information about production mechanisms and cosmic-ray acceleration. In the high-energy regime, one of the dominant mechanisms for gamma-ray production is the decay of neutral pions produced in interactions of ultra-relativistic cosmic-ray nuclei and interstellar matter. Presented here is a parametric model for calculations of inclusive cross sections and transverse momentum distributions for secondary particles--gamma rays, e{sup {+-}}, {nu}{sub e}, {bar {nu}}{sub e}, {nu}{sub {mu}} and {bar {nu}}{sub {mu}}--produced in proton-proton interactions. This parametric model is derived on the proton-proton interaction model proposed by Kamae et al.; it includes the diffraction dissociation process, Feynman-scaling violation and the logarithmically rising inelastic proton-proton cross section. To improve fidelity to experimental data for lower energies, two baryon resonance excitation processes were added; one representing the {Delta}(1232) and the other multiple resonances with masses around 1600 MeV/c{sup 2}. The model predicts the power-law spectral index for all secondary particle to be about 0.05 lower in absolute value than that of the incident proton and their inclusive cross sections to be larger than those predicted by previous models based on the Feynman-scaling hypothesis. The applications of the presented model in astrophysics are plentiful. It has been implemented into the Galprop code to calculate the contribution due to pion decays in the Galactic plane. The model has also been used to estimate the cosmic-ray flux in the Large Magellanic Cloud based on HI, CO and gamma-ray observations. The transverse momentum distributions enable calculations when the proton distribution is anisotropic. It is shown that the gamma-ray spectrum and flux due to a pencil beam of

  5. A RUNAWAY BLACK HOLE IN COSMOS: GRAVITATIONAL WAVE OR SLINGSHOT RECOIL?

    SciTech Connect (OSTI)

    Civano, F.; Elvis, M.; Lanzuisi, G.; Hao, H.; Aldcroft, T.; Jahnke, K.; Zamorani, G.; Comastri, A.; Bolzonella, M.; Blecha, L.; Loeb, A.; Bongiorno, A.; Brusa, M.; Leauthaud, A.; Mainieri, V.; Piconcelli, E.; Salvato, M.; Scoville, N.; Trump, J.; Vignali, C.

    2010-07-01

    We present a detailed study of a peculiar source detected in the COSMOS survey at z = 0.359. Source CXOC J100043.1+020637, also known as CID-42, has two compact optical sources embedded in the same galaxy. The distance between the two, measured in the HST/ACS image, is 0.''495 {+-} 0.''005 that, at the redshift of the source, corresponds to a projected separation of 2.46 {+-} 0.02 kpc. A large ({approx}1200 km s{sup -1}) velocity offset between the narrow and broad components of H{beta} has been measured in three different optical spectra from the VLT/VIMOS and Magellan/IMACS instruments. CID-42 is also the only X-ray source in COSMOS, having in its X-ray spectra a strong redshifted broad absorption iron line and an iron emission line, drawing an inverted P-Cygni profile. The Chandra and XMM-Newton data show that the absorption line is variable in energy by {Delta}E = 500 eV over four years and that the absorber has to be highly ionized in order not to leave a signature in the soft X-ray spectrum. That these features-the morphology, the velocity offset, and the inverted P-Cygni profile-occur in the same source is unlikely to be a coincidence. We envisage two possible explanations, both exceptional, for this system: (1) a gravitational wave (GW) recoiling black hole (BH), caught 1-10 Myr after merging; or (2) a Type 1/Type 2 system in the same galaxy where the Type 1 is recoiling due to the slingshot effect produced by a triple BH system. The first possibility gives us a candidate GW recoiling BH with both spectroscopic and imaging signatures. In the second case, the X-ray absorption line can be explained as a BAL-like outflow from the foreground nucleus (a Type 2 AGN) at the rearer one (a Type 1 AGN), which illuminates the otherwise undetectable wind, giving us the first opportunity to show that fast winds are present in obscured active galactic nuclei (AGNs), and possibly universal in AGNs.

  6. Extended main sequence turnoffs in intermediate-age star clusters: a correlation between turnoff width and early escape velocity

    SciTech Connect (OSTI)

    Goudfrooij, Paul; Kozhurina-Platais, Vera; Kalirai, Jason S.; Correnti, Matteo E-mail: verap@stsci.edu E-mail: correnti@stsci.edu; and others

    2014-12-10

    We present a color-magnitude diagram analysis of deep Hubble Space Telescope imaging of a mass-limited sample of 18 intermediate-age (1-2 Gyr old) star clusters in the Magellanic Clouds, including eight clusters for which new data were obtained. We find that all star clusters in our sample feature extended main-sequence turnoff (eMSTO) regions that are wider than can be accounted for by a simple stellar population (including unresolved binary stars). FWHM widths of the MSTOs indicate age spreads of 200-550 Myr. We evaluate the dynamical evolution of clusters with and without initial mass segregation. Our main results are (1) the fraction of red clump (RC) stars in secondary RCs in eMSTO clusters scales with the fraction of MSTO stars having pseudo-ages of ?1.35 Gyr; (2) the width of the pseudo-age distributions of eMSTO clusters is correlated with their central escape velocity v {sub esc}, both currently and at an age of 10 Myr. We find that these two results are unlikely to be reproduced by the effects of interactive binary stars or a range of stellar rotation velocities. We therefore argue that the eMSTO phenomenon is mainly caused by extended star formation within the clusters; and (3) we find that v {sub esc} ? 15 km s{sup 1} out to ages of at least 100 Myr for all clusters featuring eMSTOs, and v {sub esc} ? 12 km s{sup 1} at all ages for two lower-mass clusters in the same age range that do not show eMSTOs. We argue that eMSTOs only occur for clusters whose early escape velocities are higher than the wind velocities of stars that provide material from which second-generation stars can form. The threshold of 12-15 km s{sup 1} is consistent with wind velocities of intermediate-mass asymptotic giant branch stars and massive binary stars in the literature.

  7. The Difference Imaging Pipeline for the Transient Search in the Dark Energy Survey

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Kessler, R.

    2015-09-09

    We describe the operation and performance of the difference imaging pipeline (DiffImg) used to detect transients in deep images from the Dark Energy Survey Supernova program (DES-SN) in its first observing season from 2013 August through 2014 February. DES-SN is a search for transients in which ten 3 deg2 fields are repeatedly observed in the g, r, i, zpassbands with a cadence of about 1 week. Our observing strategy has been optimized to measure high-quality light curves and redshifts for thousands of Type Ia supernovae (SNe Ia) with the goal of measuring dark energy parameters. The essential DiffImg functions aremore » to align each search image to a deep reference image, do a pixel-by-pixel subtraction, and then examine the subtracted image for significant positive detections of point-source objects. The vast majority of detections are subtraction artifacts, but after selection requirements and image filtering with an automated scanning program, there are ~130 detections per deg2 per observation in each band, of which only ~25% are artifacts. Of the ~7500 transients discovered by DES-SN in its first observing season, each requiring a detection on at least two separate nights, Monte Carlo (MC) simulations predict that 27% are expected to be SNe Ia or core-collapse SNe. Another ~30% of the transients are artifacts in which a small number of observations satisfy the selection criteria for a single-epoch detection. Spectroscopic analysis shows that most of the remaining transients are AGNs and variable stars. Fake SNe Ia are overlaid onto the images to rigorously evaluate detection efficiencies and to understand the DiffImg performance. Furthermore, the DiffImg efficiency measured with fake SNe agrees well with expectations from a MC simulation that uses analytical calculations of the fluxes and their uncertainties. In our 8 "shallow" fields with single-epoch 50% completeness depth ~23.5, the SN Ia efficiency falls to 1/2 at redshift z ≈ 0.7; in our 2 "deep

  8. The Difference Imaging Pipeline for the Transient Search in the Dark Energy Survey

    SciTech Connect (OSTI)

    Kessler, R.

    2015-09-09

    We describe the operation and performance of the difference imaging pipeline (DiffImg) used to detect transients in deep images from the Dark Energy Survey Supernova program (DES-SN) in its first observing season from 2013 August through 2014 February. DES-SN is a search for transients in which ten 3 deg2 fields are repeatedly observed in the g, r, i, zpassbands with a cadence of about 1 week. Our observing strategy has been optimized to measure high-quality light curves and redshifts for thousands of Type Ia supernovae (SNe Ia) with the goal of measuring dark energy parameters. The essential DiffImg functions are to align each search image to a deep reference image, do a pixel-by-pixel subtraction, and then examine the subtracted image for significant positive detections of point-source objects. The vast majority of detections are subtraction artifacts, but after selection requirements and image filtering with an automated scanning program, there are ~130 detections per deg2 per observation in each band, of which only ~25% are artifacts. Of the ~7500 transients discovered by DES-SN in its first observing season, each requiring a detection on at least two separate nights, Monte Carlo (MC) simulations predict that 27% are expected to be SNe Ia or core-collapse SNe. Another ~30% of the transients are artifacts in which a small number of observations satisfy the selection criteria for a single-epoch detection. Spectroscopic analysis shows that most of the remaining transients are AGNs and variable stars. Fake SNe Ia are overlaid onto the images to rigorously evaluate detection efficiencies and to understand the DiffImg performance. Furthermore, the DiffImg efficiency measured with fake SNe agrees well with expectations from a MC simulation that uses analytical calculations of the fluxes and their uncertainties. In our 8 "shallow" fields with single-epoch 50% completeness depth ~23.5, the SN Ia efficiency falls to 1/2 at redshift z ≈ 0.7; in our

  9. Réunion publique HR

    ScienceCinema (OSTI)

    None

    2011-10-06

    Chers Collègues,Je me permets de vous rappeler qu'une réunion publique organisée par le Département HR se tiendra aujourd'hui:Vendredi 30 avril 2010 à 9h30 dans l'Amphithéâtre principal (café offert dès 9h00).Durant cette réunion, des informations générales seront données sur:le CERN Admin e-guide, qui est un nouveau guide des procédures administratives du CERN ayant pour but de faciliter la recherche d'informations pratiques et d'offrir un format de lecture convivial;le régime d'Assurance Maladie de l'Organisation (présentation effectuée par Philippe Charpentier, Président du CHIS Board) et;la Caisse de Pensions (présentation effectuée par Théodore Economou, Administrateur de la Caisse de Pensions du CERN).Une transmission simultanée de cette réunion sera assurée dans l'Amphithéâtre BE de Prévessin et également disponible à l'adresse suivante: http://webcast.cern.chJe me réjouis de votre participation!Meilleures salutations,Anne-Sylvie CatherinChef du Département des Ressources humaines__________________________________________________________________________________Dear Colleagues,I should like to remind you that a plublic meeting organised by HR Department will be held today:Friday 30 April 2010 at 9:30 am in the Main Auditorium (coffee from 9:00 am).During this meeting, general information will be given about:the CERN Admin e-guide which is a new guide to the Organization's administrative procedures, drawn up to facilitate the retrieval of practical information and to offer a user-friendly format;the CERN Health Insurance System (presentation by Philippe Charpentier, President of the CHIS Board) and;the Pension Fund (presentation by Theodore Economou, Administrator of the CERN Pension Fund).A simultaneous transmission of this meeting will be broadcast in the BE Auditorium at Prévessin and will also be available at the following address. http://webcast.cern.chI look forward to your participation!Best regards,Anne-Sylvie Catherin

  10. Comparative study of microwave radiation-induced magnetoresistive oscillations induced by circularly- and linearly- polarized photo-excitation

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Ye, Tianyu; Liu, Han -Chun; Wang, Zhuo; Wegscheider, W.; Mani, Ramesh G.

    2015-10-09

    A comparative study of the radiation-induced magnetoresistance oscillations in the high mobility GaAs/AlGaAs heterostructure two dimensional electron system (2DES) under linearly- and circularly- polarized microwave excitation indicates a profound difference in the response observed upon rotating the microwave launcher for the two cases, although circularly polarized microwave radiation induced magnetoresistance oscillations observed at low magnetic fields are similar to the oscillations observed with linearly polarized radiation. For the linearly polarized radiation, the magnetoresistive response is a strong sinusoidal function of the launcher rotation (or linear polarization) angle, θ. As a result, for circularly polarized radiation, the oscillatory magnetoresistive response ismore » hardly sensitive to θ.« less

  11. Offshore Wind Guidance Document: Oceanography and Sediment Stability (Version 1) Development of a Conceptual Site Model.

    SciTech Connect (OSTI)

    Roberts, Jesse D.; Jason Magalen; Craig Jones

    2014-06-01

    This guidance document provide s the reader with an overview of the key environmental considerations for a typical offshore wind coastal location and the tools to help guide the reader through a thoro ugh planning process. It will enable readers to identify the key coastal processes relevant to their offshore wind site and perform pertinent analysis to guide siting and layout design, with the goal of minimizing costs associated with planning, permitting , and long - ter m maintenance. The document highlight s site characterization and assessment techniques for evaluating spatial patterns of sediment dynamics in the vicinity of a wind farm under typical, extreme, and storm conditions. Finally, the document des cribe s the assimilation of all of this information into the conceptual site model (CSM) to aid the decision - making processes.

  12. Les vies de Galilée

    ScienceCinema (OSTI)

    None

    2011-10-06

    Qu'est-ce que l'astronomie? A quoi sert-elle ? Qui était Galilée ? Une soirée avec Fiami, auteur et dessinateur autour des vies de Galilée, titre de son nouvel ouvrage. Galilée y joue le protagoniste ou le complice de grandes découvertes à différentes époques et sous divers profils : Galilée à Babylone (-568) | Galilée à Alexandrie (-197) | Galilée en Inde (499) | Galilée à Venise (1609) | Galilée et Halley (1705) | Galilée revient (2009) Dans le cadre de l'année mondiale de l'astronomie. » Tout public » Entrée libre » Réservation groupes au +41 (0)22 767 76 76

  13. Memorial W.Gentner

    ScienceCinema (OSTI)

    None

    2011-04-25

    Le DG H.Schopper fait une introduction pour la commémoration et cérémonie de la vie et du travail du Prof.Wolfgang Gentner. W. Gentner, physicien allemand, né en 1906 à Francfort et mort en septembre 1980 à Heidelberg, était directeur au Cern de 1955 à 1960, président du "scientific policy commitee" de 1968 à 1971 et président du Conseil du Cern de 1972 à 1974. Il était un des fondateurs du Cern et 4 personnes qui l'ont bien connu lui rendent hommage, entre autres un de ses élèves, ainsi que Mme ?, J.B.Adams et O.Sheffard(?)

  14. Final report for the virtual channel encryptor laboratory directed research and development project

    SciTech Connect (OSTI)

    Gibson, D.J.; Sarfaty, R.A.

    1997-08-01

    A workstation with a single physical connection to a data communications network may have a requirement for simultaneous `virtual` communication channels to more than one destination. This report describes the development of techniques based on the Data Encryption Standard (DES) which encrypt these virtual channels to secure the data being transmitted against unauthorized access. A software module has been developed for the UNIX operating system using these techniques for encryption, and some development has also been done on a hardware device to be included between the workstation and network which can also provide these functions. The material presented in this report will be useful to those with a need to protect information in data communications systems from unauthorized access.

  15. Cultural Alimentation in Latin America

    ScienceCinema (OSTI)

    None

    2011-04-25

    Le Prof. Paolo Freire(nom?) a dirigé en Brésil un plan national d'alphabétisatation d'adultes. La base de sa méthode est d'essayer de ne pas rester sur la mécanique du mot, mais de le relier avec la réalité sociale et donner un réveillement critique de la conscience populaire en face de la réalité historique du pays. Il était professeur d'histoire et de philosophie de Récife, puis exilé et depuis il était prof. à Harvard, a travaillé à l'Unesco et est maintenant conseiller spécial à l'Office d'Education du centre oecuménique des églises

  16. Club of Rome

    ScienceCinema (OSTI)

    None

    2011-04-25

    Le Club de Rome s'est fait connaître du grand public par la publication du premier ouvrage "Halte à la croissance" qui a fait l'object d'un débat, il y a 2 ans. Le Prof. Tinbergen a commencé par s'adonner à la physique, il est docteur en physique et très tôt il s'est tourné vers les problèmes sociaux économiques. Il est expert auprès des nombreux gouvernements et organisations internationales et il a vu ses travaux couronnés par le prix Nobel en 1969.

  17. Local Voltage Support from Distributed Energy Resources to Prevent Air Conditioner Motor Stalling

    SciTech Connect (OSTI)

    Baone, Chaitanya A; Xu, Yan; Kueck, John D

    2010-01-01

    Microgrid voltage collapse often happens when there is a high percentage of low inertia air-conditioning (AC) motors in the power systems. The stalling of the AC motors results in Fault Induced Delayed Voltage Recovery (FIDVR). A hybrid load model including typical building loads, AC motor loads, and other induction motor loads is built to simulate the motoring stalling phenomena. Furthermore, distributed energy resources (DE) with local voltage support capability are utilized to boost the local bus voltage during a fault, and prevent the motor stalling. The simulation results are presented. The analysis of the simulation results show that local voltage support from multiple DEs can effectively and economically solve the microgrid voltage collapse problem.

  18. Large linear magnetoresistance in a GaAs/AlGaAs heterostructure

    SciTech Connect (OSTI)

    Aamir, Mohammed Ali Goswami, Srijit Ghosh, Arindam; Baenninger, Matthias; Farrer, Ian; Ritchie, David A.; Tripathi, Vikram; Pepper, Michael

    2013-12-04

    We report non-saturating linear magnetoresistance (MR) in a two-dimensional electron system (2DES) at a GaAs/AlGaAs heterointerface in the strongly insulating regime. We achieve this by driving the gate voltage below the pinch-off point of the device and operating it in the non-equilibrium regime with high source-drain bias. Remarkably, the magnitude of MR is as large as 500% per Tesla with respect to resistance at zero magnetic field, thus dwarfing most non-magnetic materials which exhibit this linearity. Its primary advantage over most other materials is that both linearity and the enormous magnitude are retained over a broad temperature range (0.3 K to 10 K), thus making it an attractive candidate for cryogenic sensor applications.

  19. Electron heating due to microwave photoexcitation in the high mobility GaAs/AlGaAs two dimensional electron system

    SciTech Connect (OSTI)

    Ramanayaka, A. N.; Mani, R. G.; Wegscheider, W.

    2013-12-04

    We extract the electron temperature in the microwave photo-excited high mobility GaAs/AlGaAs two dimensional electron system (2DES) by studying the influence of microwave radiation on the amplitude of Shubnikov-de Haas oscillations (SdHOs) in a regime where the cyclotron frequency, ?{sub c}, and the microwave angular frequency, ?, satisfy 2? ? ?{sub c} ? 3.5? The results indicate that increasing the incident microwave power has a weak effect on the amplitude of the SdHOs and therefore the electron temperature, in comparison to the influence of modest temperature changes on the dark-specimen SdH effect. The results indicate negligible electron heating under modest microwave photo-excitation, in good agreement with theoretical predictions.

  20. Heteropolymer freezing and design: Towards physical models of protein folding

    SciTech Connect (OSTI)

    Pande, Vijay S. [Chemistry Department, Stanford University, Stanford, California 94305-5080 (United States)] [Chemistry Department, Stanford University, Stanford, California 94305-5080 (United States); Grosberg, Alexander Yu. [Department of Physics, University of Minnesota, Minneapolis, Minnesota 55455 (United States)] [Department of Physics, University of Minnesota, Minneapolis, Minnesota 55455 (United States); Tanaka, Toyoichi [Department of Physics and Center for Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States)] [Department of Physics and Center for Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States)

    2000-01-01

    Protein folding has become one of the most actively studied problems in modern molecular biophysics. Approaches to the problem combine ideas from the physics of disordered systems, polymer physics, and molecular biology. Much can be learned from the statistical properties of model heteropolymers, the chain molecules having different monomers in irregular sequences. Even in highly evolved proteins, there is a strong random element in the sequences, which gives rise to a statistical ensemble of sequences for a given folded shape. Simple analytic models give rise to phase transitions between random, glassy, and folded states, depending on the temperature T and the design temperature T{sup des} of the ensemble of sequences. Besides considering the analytic results obtainable in a random-energy model and in the Flory mean-field model of polymers, the article reports on confirming numerical simulations. (c) 2000 The American Physical Society.

  1. The Sixth Omega Laser Facility Users Group Workshop

    SciTech Connect (OSTI)

    Petrasso, R. D.

    2014-10-01

    A capacity gathering of over 100 researchers from 25 universities and laboratories met at the Laboratory for Laser Energetics (LLE) for the Sixth Omega Laser Facility Users Group (OLUG) workshop. The purpose of the 2.5-day workshop was to facilitate communications and exchanges among individual OMEGA users, and between users and the LLE management; to present ongoing and proposed research; to encourage research opportunities and collaborations that could be undertaken at the Omega Laser Facility and in a complementary fashion at other facilities [such as the National Ignition Facility (NIF) or the Laboratoire pour lUtilisation des Lasers Intenses (LULI)]; to provide an opportunity for students, postdoctoral fellows, and young researchers to present their research in an informal setting; and to provide feedback from the users to LLE management about ways to improve and keep the facility and future experimental campaigns at the cutting edge.

  2. LANL: AOT & LANSCE The Pulse March 2010

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Los Alamos National Laboratory * Est. 1943 The Pulse-Newsletter of the Los Alamos Neutron Science Center and Accelerator Operations and Technology Division I N S I D E 2 Tajima receives DOe early career awarD 2 NeuTrON reflec- TOmeTry prOviDes firsT sub-NaNOmeTer visualizaTiON Of live cell aDhesiON 3 creaTiNg a high- efficieNcy cOmpacT iON acceleraTOr, aN alTerNaTive TO larger, mOre cOsTly sTruc- Tures 4 heaDs up! LANSCE beam reliability achieves "world class" ranking AOT has issued

  3. LANL: AOT & LANSCE The Pulse October 2011

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    1 Los Alamos National Laboratory * Est. 1943 The Pulse-Newsletter of the Los Alamos Neutron Science Center and Accelerator Operations and Technology Division I N S I D E 3 From Alex's Desk 3 NeutroN scAtteriNg proviDes iNsight iNto eNzymAtic DegrADAtioN oF cellulose 4 NeutroN totAl scAtteriNg moNitors shiFts iN vAleNce stAtes 5 NeutroN reFlec- tometry exAmiNes the perFormANce oF rADiAtioN-resistANt mAteriAls 6 meAsuriNg the FissioN NeutroN spectrum At lANsce 7 heADs up! Daniel Shoemaker receives

  4. Tomography and weak lensing statistics

    SciTech Connect (OSTI)

    Munshi, Dipak; Coles, Peter; Kilbinger, Martin E-mail: peter.coles@astro.cf.ac.uk

    2014-04-01

    We provide generic predictions for the lower order cumulants of weak lensing maps, and their correlators for tomographic bins as well as in three dimensions (3D). Using small-angle approximation, we derive the corresponding one- and two-point probability distribution function for the tomographic maps from different bins and for 3D convergence maps. The modelling of weak lensing statistics is obtained by adopting a detailed prescription for the underlying density contrast that involves hierarchal ansatz and lognormal distribution. We study the dependence of our results on cosmological parameters and source distributions corresponding to the realistic surveys such as LSST and DES. We briefly outline how photometric redshift information can be incorporated in our results. We also show how topological properties of convergence maps can be quantified using our results.

  5. The Fifth Omega Laser Facility Users Group Workshop

    SciTech Connect (OSTI)

    Petrasso, R. D.

    2015-10-01

    A capacity gathering of over 100 researchers from 25 universities and laboratories met at the Laboratory for Laser Energetics (LLE) for the Fifth Omega Laser Facility Users Group (OLUG) workshop. The purpose of the 2.5-day workshop was to facilitate communications and exchanges among individual Omega users and between users and the LLE management; to present ongoing and proposed research; to encourage research opportunities and collaborations that could be undertaken at the Omega Laser Facility and in a complementary fashion at other facilities [such as the National Ignition Facility (NIF) or the Laboratoire pour l’Utilisation des Lasers Intenses (LULI)]; to provide an opportunity for students, postdoctoral fellows, and young researchers to present their research in an informal setting; and to provide feedback to LLE management from the users about ways to improve the facility and future experimental campaigns.

  6. Supporting Advanced Scientific Computing Research * Basic Energy Sciences * Biological

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Energy S ciences N etwork Enabling Virtual Science June 9, 2009 Steve C o/er steve@es.net Dept. H ead, E nergy S ciences N etwork Lawrence B erkeley N aDonal L ab The E nergy S ciences N etwork The D epartment o f E nergy's O ffice o f S cience i s o ne o f t he l argest s upporters o f basic r esearch i n t he p hysical s ciences i n t he U .S. * Directly s upports t he r esearch o f s ome 1 5,000 s cienDsts, p ostdocs a nd g raduate s tudents at D OE l aboratories, u niversiDes, o ther F

  7. High Energy Physics at the University of Illinois

    SciTech Connect (OSTI)

    Liss, Tony M.; Thaler, Jon J.

    2013-07-26

    This is the final report for DOE award DE-FG02-91ER40677 (“High Energy Physics at the University of Illinois”), covering the award period November 1, 2009 through April 30, 2013. During this period, our research involved particle physics at Fermilab and CERN, particle physics related cosmology at Fermilab and SLAC, and theoretical particle physics. Here is a list of the activities described in the final report: * The CDF Collaboration at the Fermilab Tevatron * Search For Lepton Flavor Violation in the Mu2e Experiment At Fermilab * The ATLAS Collaboration at the CERN Large Hadron Collider * the Study of Dark Matter and Dark Energy: DES and LSST * Lattice QCD * String Theory and Field Theory * Collider Phenomenology

  8. Material report in support to RCC-MRX code 2010 stainless steel parts and products

    SciTech Connect (OSTI)

    Ancelet, Olivier; Lebarbe, Thierry; Dubiez-Le Goff, Sophie; Bonne, Dominique; Gelineau, Odile

    2012-07-01

    This paper presents the Material Report dedicated to stainless steels parts and products issued by AFCEN (Association Francaise pour les regles de Conception et de Construction des Materiels des Chaudieres Electro-Nucleaires) in support to RCC-MRx 2010 Code. The RCC-MRx Code is the result of the merger of the RCC-MX 2008, developed in the context of the research reactor Jules Horowitz Reactor project, in the RCC-MR 2007, which set up rules applicable to the design of components operating at high temperature and to the Vacuum Vessel of ITER (a presentation of RCC-MRx 2010 Code is the subject of another paper proposed in this Congress; it explains in particular the status of this Code). This Material Report is part of a set of Criteria of RCC-MRx (this set of Criteria is under construction). The Criteria aim at explaining the design and construction rules of the Code. They cover analyses rules as well as part procurement, welding, methods of tests and examination and fabrication rules. The Material Report particularly provides justifications and explanations on requirements and features dealing with parts and products proposed in the Code. The Material Report contains the following information: Introduction of the grade(s): codes and standards and Reference Procurement Specifications covering parts and products, applications and experience gained, - Physical properties, - Mechanical properties used for design calculations (base metal and welds): basic mechanical properties, creep mechanical properties, irradiated mechanical properties, - Fabrication: experience gained, metallurgy, - Welding: weldability, experience gained during welding and repair procedure qualifications, - Non-destructive examination, - In-service behaviour. In the article, examples of data supplied in the Material Report dedicated to stainless steels will be exposed. (authors)

  9. Facility design, construction, and operation

    SciTech Connect (OSTI)

    1995-04-01

    France has been disposing of low-level radioactive waste (LLW) at the Centre de Stockage de la Manche (CSM) since 1969 and now at the Centre de Stockage de l`Aube (CSA) since 1992. In France, several agencies and companies are involved in the development and implementation of LLW technology. The Commissariat a l`Energie Atomic (CEA), is responsible for research and development of new technologies. The Agence National pour la Gestion des Dechets Radioactifs is the agency responsible for the construction and operation of disposal facilities and for wastes acceptance for these facilities. Compagnie Generale des Matieres Nucleaires provides fuel services, including uranium enrichment, fuel fabrication, and fuel reprocessing, and is thus one generator of LLW. Societe pour les Techniques Nouvelles is an engineering company responsible for commercializing CEA waste management technology and for engineering and design support for the facilities. Numatec, Inc. is a US company representing these French companies and agencies in the US. In Task 1.1 of Numatec`s contract with Martin Marietta Energy Systems, Numatec provides details on the design, construction and operation of the LLW disposal facilities at CSM and CSA. Lessons learned from operation of CSM and incorporated into the design, construction and operating procedures at CSA are identified and discussed. The process used by the French for identification, selection, and evaluation of disposal technologies is provided. Specifically, the decisionmaking process resulting in the change in disposal facility design for the CSA versus the CSM is discussed. This report provides` all of the basic information in these areas and reflects actual experience to date.

  10. The Pennsylvanian and Permian Oquirrh-Wood River basin

    SciTech Connect (OSTI)

    Geslin, J.K. . Dept. of Earth and Planetary Sciences)

    1993-04-01

    Strata of the Middle Pennsylvanian to Lower Permian Oquirrh-Wood River Basin (OWRB) lie unconformably above the Antler orogenic belt and flysch trough/starved basin in NW Utah, NE Nevada, and SC Idaho. Strata of the basin, now separated geographically by the Neogene Snake River Plain, show similar subsidence histories, identical mixed carbonate-siliciclastic sedimentary fill, and identical chert pebble conglomerate beds supplied by one or more DesMoinesian uplifts containing Lower Paleozoic strata. This conglomerate, of the lower Sun Valley Group, Snaky Canyon Formation, and parts of the Oquirrh Formation, was reworked progressively southward, to at least the Idaho-Utah border. It is present in strata as young as Virgilian. Virgilian to Leonardian rocks are ubiquitously fine-grained mixed carbonate-siliciclastic turbidites. These rocks contain cratonal, well-sorbed subarkosic and quartzose sand and silt in part derived from the Canadian Shield. This siliciclastic fraction is intimately mixed with arenaceous micritized skeletal material and peloids derived from an eastern carbonate platform represented by the Snaky Canyon Formation in east-central Idaho, an eastern facies of the Eagle Creek Member, Wood River Formation in the Boulder Mountains, and the Oquirrh Formation in the Deep Creek Mountains. Subsidence of the OWRB may have been caused by two phases (DesMoinesian and Wolfcampian to Leonardian) of crustal loading by continental margin tectonism to the west. An elevated rim separated the OWRB from coeval volcanogenic basins to the west. Earlier, Antler-age structures may have been reactivated. A new pulse of tectonism occurred in Leonardian to Guadalupian time as in most places carbonatic and phosphatic strata of the Leonardian to Guadalupian Park City and Phosphoria Formation overlie OWRB strata, with different geographic arrangement of basinal, slope, and shelf depocenters.

  11. The Argonne Leadership Computing Facility 2010 annual report.

    SciTech Connect (OSTI)

    Drugan, C.

    2011-05-09

    -class computers by a factor of a thousand. Pete Beckman, who served as the ALCF's Director for the past few years, has been named director of the newly created Exascale Technology and Computing Institute (ETCi). The institute will focus on developing exascale computing to extend scientific discovery and solve critical science and engineering problems. Just as Pete's leadership propelled the ALCF to great success, we know that that ETCi will benefit immensely from his expertise and experience. Without question, the future of supercomputing is certainly in good hands. I would like to thank Pete for all his effort over the past two years, during which he oversaw the establishing of ALCF2, the deployment of the Magellan project, increases in utilization, availability, and number of projects using ALCF1. He managed the rapid growth of ALCF staff and made the facility what it is today. All the staff and users are better for Pete's efforts.

  12. The RR Lyrae stars: New perspectives

    SciTech Connect (OSTI)

    McNamara, D. H.; Barnes, J. E-mail: jonathan.barnes@slcc.edu

    2014-02-01

    We demonstrate that the Oosterhoff II (Oo II) RR Lyrae ab variables are hotter by ?270 K, at the same period, than Oo I variables. Or, at the same ((B) (V)){sub 0} value the Oo II variables have larger radii than Oo I variables. This accounts for the reason Oo II variables are brighter (0.12-0.20 mag) than Oo I variables. The dependence of the light amplitude of RR Lyrae variables on temperature is independent of Oo type. This makes it possible to derive an accurate set of equations to relate intrinsic (B V){sub 0} color indices to light amplitudes, which in turn can be used to determine the interstellar reddening (E (B V)). With just a few variables (?5), it is possible to determine the E (B V) to an accuracy of <0.01 mag in the absence of systematic photometric errors. We discuss the errors introduced in color excess determinations by including the Blazhko stars in a solution. A comparison of color excess values of 23 globular clusters and two regions of the Large Magellanic Cloud (LMC), determined with the aid of our newly developed equations, are found to compare favorably (?0.01 mag) with color excess values found in the literature. Four new Oo III variables, some found in metal-poor clusters, are discussed. An analysis of the galactic-field variables indicates the majority are Oo I and Oo II variables, but a few short-period (log P < 0.36) metal-strong variables, so far not found in galactic globular clusters are evidently ?0.30 mag fainter than Oo I variables. Oo III variables may also be present in the field. We conclude that the RR Lyrae ab variables are primarily restricted to four sequences or groups. If we assume that the Oo I variables' mean absolute magnitude is Mv = 0.61, the mean absolute magnitudes of the other three sequences are: short-period variables Mv ? 0.89 mag, Oo II Mv ? 0.43 mag, and Oo III Mv ? 0.29 mag. The Oo I fundamental RR Lyrae ab red edge (FRE) and fundamental blue edge (FBE) occur at approximately the following

  13. Nicotine impairs cyclooxygenase-2-dependent kinin-receptor-mediated murine airway relaxations

    SciTech Connect (OSTI)

    Xu, Yuan Cardell, Lars-Olaf

    2014-02-15

    Introduction: Cigarette smoke induces local inflammation and airway hyperreactivity. In asthmatics, it worsens the symptoms and increases the risk for exacerbation. The present study investigates the effects of nicotine on airway relaxations in isolated murine tracheal segments. Methods: Segments were cultured for 24 h in the presence of vehicle, nicotine (10 ?M) and/or dexamethasone (1 ?M). Airway relaxations were assessed in myographs after pre-contraction with carbachol (1 ?M). Kinin receptors, cyclooxygenase (COX) and inflammatory mediator expressions were assessed by real-time PCR and confocal-microscopy-based immunohistochemistry. Results: The organ culture procedure markedly increased bradykinin- (selective B{sub 2} receptor agonist) and des-Arg{sup 9}-bradykinin- (selective B{sub 1} receptor agonist) induced relaxations, and slightly increased relaxation induced by isoprenaline, but not that induced by PGE{sub 2}. The kinin receptor mediated relaxations were epithelium-, COX-2- and EP2-receptor-dependent and accompanied by drastically enhanced mRNA levels of kinin receptors, as well as inflammatory mediators MCP-1 and iNOS. Increase in COX-2 and mPGES-1 was verified both at mRNA and protein levels. Nicotine selectively suppressed the organ-culture-enhanced relaxations induced by des-Arg{sup 9}-bradykinin and bradykinin, at the same time reducing mPGES-1 mRNA and protein expressions. ?7-nicotinic acetylcholine receptor inhibitors ?-bungarotoxin and MG624 both blocked the nicotine effects on kinin B{sub 2} receptors, but not those on B{sub 1}. Dexamethasone completely abolished kinin-induced relaxations. Conclusion: It is tempting to conclude that a local inflammatory process per se could have a bronchoprotective component by increasing COX-2 mediated airway relaxations and that nicotine could impede this safety mechanism. Dexamethasone further reduced airway inflammation together with relaxations. This might contribute to the steroid resistance seen in some

  14. Northeast Clean Energy Application Center

    SciTech Connect (OSTI)

    Bourgeois, Tom

    2013-09-30

    From October 1, 2009 through September 30, 2013 (“contract period”), the Northeast Clean Energy Application Center (“NE-CEAC”) worked in New York and New England (Connecticut, Rhode Island, Vermont, Massachusetts, New Hampshire, and Maine) to create a more robust market for the deployment of clean energy technologies (CETs) including combined heat and power (CHP), district energy systems (DES), and waste heat recovery (WHR) systems through the provision of technical assistance, education and outreach, and strategic market analysis and support for decision-makers. CHP, DES, and WHR can help reduce greenhouse gas emissions, reduce electrical and thermal energy costs, and provide more reliable energy for users throughout the United States. The NE-CEAC’s efforts in the provision of technical assistance, education and outreach, and strategic market analysis and support for decision-makers helped advance the market for CETs in the Northeast thereby helping the region move towards the following outcomes: • Reduction of greenhouse gas emissions and criteria pollutants • Improvements in energy efficiency resulting in lower costs of doing business • Productivity gains in industry and efficiency gains in buildings • Lower regional energy costs • Strengthened energy security • Enhanced consumer choice • Reduced price risks for end-users • Economic development effects keeping more jobs and more income in our regional economy Over the contract period, NE-CEAC provided technical assistance to approximately 56 different potential end-users that were interested in CHP and other CETs for their facility or facilities. Of these 56 potential end-users, five new CHP projects totaling over 60 MW of install capacity became operational during the contract period. The NE-CEAC helped host numerous target market workshops, trainings, and webinars; and NE-CEAC staff delivered presentations at many other workshops and conferences. In total, over 60 different workshops

  15. Clean Energy Application Center

    SciTech Connect (OSTI)

    Freihaut, Jim

    2013-09-30

    The Mid Atlantic Clean Energy Application Center (MACEAC), managed by The Penn State College of Engineering, serves the six states in the Mid-Atlantic region (Pennsylvania, New Jersey, Delaware, Maryland, Virginia and West Virginia) plus the District of Columbia. The goals of the Mid-Atlantic CEAC are to promote the adoption of Combined Heat and Power (CHP), Waste Heat Recovery (WHR) and District Energy Systems (DES) in the Mid Atlantic area through education and technical support to more than 1,200 regional industry and government representatives in the region. The successful promotion of these technologies by the MACEAC was accomplished through the following efforts; (1)The MACEAC developed a series of technology transfer networks with State energy and environmental offices, Association of Energy Engineers local chapters, local community development organizations, utilities and, Penn State Department of Architectural Engineering alumni and their firms to effectively educate local practitioners about the energy utilization, environmental and economic advantages of CHP, WHR and DES; (2) Completed assessments of the regional technical and market potential for CHP, WHR and DE technologies application in the context of state specific energy prices, state energy and efficiency portfolio development. The studies were completed for Pennsylvania, New Jersey and Maryland and included a set of incentive adoption probability models used as a to guide during implementation discussions with State energy policy makers; (3) Using the technical and market assessments and adoption incentive models, the Mid Atlantic CEAC developed regional strategic action plans for the promotion of CHP Application technology for Pennsylvania, New Jersey and Maryland; (4) The CHP market assessment and incentive adoption model information was discussed, on a continuing basis, with relevant state agencies, policy makers and Public Utility Commission organizations resulting in CHP favorable incentive

  16. Direct production of hydrogen and aromatics from methane or natural gas: Review of recent U.S. patents

    SciTech Connect (OSTI)

    Lucia M. Petkovic; Daniel M. Ginosar

    2012-03-01

    Since the year 2000, the United States Patent and Trademark Office (USPTO) has granted a dozen patents for inventions related to methane dehydroaromatization processes. One of them was granted to UOP LLC (Des Plaines). It relates to a catalyst composition and preparation method. Two patents were granted to Conoco Phillips Company (Houston, TX). One was aimed at securing a process and operating conditions for methane aromatization. The other was aimed at securing a process that may be integrated with separation of wellhead fluids and blending of the aromatics produced from the gas with the crude. Nine patents were granted to ExxonMobil Chemical Patents Inc. (Houston, TX). Most of these were aimed at securing a dehydroaromatization process where methane-containing feedstock moves counter currently to a particulate catalyst. The coked catalyst is heated or regenerated either in the reactor, by cyclic operation, or in annex equipment, and returned to the reactor. The reactor effluent stream may be separated in its main components and used or recycled as needed. A brief summary of those inventions is presented in this review.

  17. Wide-field lensing mass maps from Dark Energy Survey science verification data: Methodology and detailed analysis

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Vikram, V.; Sheldon, E.; Chang, C.; Jain, B.; Bacon, D.; Amara, A.; Becker, M. R.; Bernstein, G.; Bonnett, C.; Bridle, S.; et al

    2015-07-29

    Weak gravitational lensing allows one to reconstruct the spatial distribution of the projected mass density across the sky. These mass maps provide a powerful tool for studying cosmology as they probe both luminous and dark matter. In this paper, we present a weak lensing mass map reconstructed from shear measurements in a 139 deg2 area from the Dark Energy Survey science verification data. We compare the distribution of mass with that of the foreground distribution of galaxies and clusters. The overdensities in the reconstructed map correlate well with the distribution of optically detected clusters. We demonstrate that candidate superclusters andmorevoids along the line of sight can be identified, exploiting the tight scatter of the cluster photometric redshifts. We cross-correlate the mass map with a foreground magnitude-limited galaxy sample from the same data. Our measurement gives results consistent with mock catalogs from N-body simulations that include the primary sources of statistical uncertainties in the galaxy, lensing, and photo-z catalogs. The statistical significance of the cross-correlation is at the 6.8? level with 20 arcminute smoothing. We find that the contribution of systematics to the lensing mass maps is generally within measurement uncertainties. We analyze less than 3% of the final area that will be mapped by the DES; the tools and analysis techniques developed in this paper can be applied to forthcoming larger data sets from the survey.less

  18. Fluidized-bed copper oxide process. Phase IV. Conceptual design and economic evaluation, Volume I. Final report

    SciTech Connect (OSTI)

    1994-11-30

    Universal Oil Products, Inc. (UOP) of Des Plaines, Illinois has contracted A.E. Roberts & Associates, Inc. (AERA) of Atlanta, Georgia to prepare a sensitivity analysis for the development of the Fluidized-bed Copper Oxide (FBCO) process. As proposed by AERA in September 1991, development of the FBCO process design for a 500 mega-watt (MW) unit was divided into three tasks: (1) Establishment of a Conceptual Design, (2) Conceptual Design, (3) Cost Analysis Task 1 determined the basis for a conceptual design for the 500 megawatt (MW) FBCO process. It was completed by AERA in September of 1992, and a report was submitted at that time {open_quotes}Establishment of the Design Basis for Application to a 500 MW Coal-fired Facility.{close_quotes} Task 2 gathered all pertinent data available to date and reviewed its applicability to the 500 MW FBCO process. Work on this task was carried out on a joint basis by the AERA team members: Roberts & Schaefers worked on the dense phase transport aspect of the design; Cornell and Carnegie Mellon Universities worked on the design kinetics and modeling; and AERA contributed commercial power and combustion experience. Task 3 provides budgetary cost estimates for the FBCO process and competing alternative technologies for sulfur dioxide and nitrogen oxide removal.

  19. ReSS: Resource Selection Service for National and Campus Grid Infrastructure

    SciTech Connect (OSTI)

    Mhashilkar, Parag; Garzoglio, Gabriele; Levshina, Tanya; Timm, Steve; /Fermilab

    2009-05-01

    The Open Science Grid (OSG) offers access to around hundred Compute elements (CE) and storage elements (SE) via standard Grid interfaces. The Resource Selection Service (ReSS) is a push-based workload management system that is integrated with the OSG information systems and resources. ReSS integrates standard Grid tools such as Condor, as a brokering service and the gLite CEMon, for gathering and publishing resource information in GLUE Schema format. ReSS is used in OSG by Virtual Organizations (VO) such as Dark Energy Survey (DES), DZero and Engagement VO. ReSS is also used as a Resource Selection Service for Campus Grids, such as FermiGrid. VOs use ReSS to automate the resource selection in their workload management system to run jobs over the grid. In the past year, the system has been enhanced to enable publication and selection of storage resources and of any special software or software libraries (like MPI libraries) installed at computing resources. In this paper, we discuss the Resource Selection Service, its typical usage on the two scales of a National Cyber Infrastructure Grid, such as OSG, and of a campus Grid, such as FermiGrid.

  20. Third international workshop on ice storage for cooling applications

    SciTech Connect (OSTI)

    Gorski, A.J.

    1986-04-01

    The third international workshop on ice storage for cooling applications which was informal and interactive in nature, was open to persons interested in all ice-growing technologies and in ice storage, both seasonal and diurnal. Presentations were made on some 20 topics, ranging from freezers in Alaska to ice cooling of commercial jet aircraft. Workshop tours included visits to ice-storage systems at Commonwealth Edison's facilities in Bolingbrook and Des Plaines Valley, the A.C. Neilsen builing in Northbrook, and the new State of Illinois Center in Chicago. The first workshop in the present series considered the future of ice storage and predicted applications in the agricultural sector, desalinization, and commercial ice production. Progress has been rapid in the intervening two years, and an important topic at the third workshop was the possible use of ''warm ices'' (clathrate hydrates) for energy storage. This report consists primarily of abstracts of presentations made at the workshop. Persons wishing to obtain further information about particular papers should contact the speakers directly; speakers' addresses and telephone numbers are listed in this report.