National Library of Energy BETA

Sample records for midwest southwest ia

  1. Midwest

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of Natural GasAdjustmentsShirley Ann JacksonDepartment ofOffice| DepartmentGJPPGPracticesDraft.doc Moreof EnergyMidwest

  2. Midwest Industrial Energy Efficiency Handbook

    SciTech Connect (OSTI)

    2010-06-25

    This Industrial Technologies Program handbook connects industry with the various energy efficiency resources available in the midwest.

  3. CHP in the Midwest - Presentation from the July 2010 Advancing...

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

    Midwest - Presentation from the July 2010 Advancing Renewables in the Midwest Conference CHP in the Midwest - Presentation from the July 2010 Advancing Renewables in the Midwest...

  4. MIDWEST NKS CONFERENCE REGISTRATION

    E-Print Network [OSTI]

    German, Dan-Adrian

    MIDWEST NKS CONFERENCE REGISTRATION On-line registrations will not be accepted after Sunday: Participation in all conference sessions, lectures, meals and social events Receipt of all conference materials: Conference Registrar IU Conferences 801 N. Jordan Ave., Suite 101 Bloomington, IN USA 47405 Phone: 800

  5. MEEA Midwest Energy Solutions Conference

    Broader source: Energy.gov [DOE]

    Midwest Energy Efficiency Alliance (MEEA) is hosting its annual conference at the Chicago Hilton and Towers in Chicago, IL, on Jan. 28-30, 2015.

  6. Midwest Hydro Users Group Meeting

    Office of Energy Efficiency and Renewable Energy (EERE)

    The Midwest Hydro Users Group will be holding their annual Fall meeting on November 12th and 13th in Wausau, Wisconsin.  An Owners-only meeting on the afternoon of the 12th followed by a full...

  7. Evolution of the Midwest ISO

    E-Print Network [OSTI]

    Tesfatsion, Leigh

    Electric Power Corporation · Wolverine Power Supply Cooperative Transmission Owning Members #12;Non-Transmission, non-profit grid operator for the transmission of high voltage electricity across much of the Midwest Transmission Organization (RTO) #12;Scope (with SPP) 150+ GW peak load 144,000+ miles of transmission lines 20

  8. Midwest Clean Energy Application Center

    SciTech Connect (OSTI)

    Cuttica, John; Haefke, Cliff

    2013-12-31

    The Midwest Clean Energy Application Center (CEAC) was one of eight regional centers that promoted and assisted in transforming the market for combined heat and power (CHP), waste heat to power (WHP), and district energy (DE) technologies and concepts throughout the United States between October 1, 2009 and December 31, 2013. The key services the CEACs provided included: ? Market Opportunity Analyses – Supporting analyses of CHP market opportunities in diverse markets including industrial, federal, institutional, and commercial sectors. ? Education and Outreach – Providing information on the energy and non-energy benefits and applications of CHP to state and local policy makers, regulators, energy end-users, trade associations and others. Information was shared on the Midwest CEAC website: www.midwestcleanergy.org. ? Technical Assistance – Providing technical assistance to end-users and stakeholders to help them consider CHP, waste heat to power, and/or district energy with CHP in their facility and to help them through the project development process from initial CHP screening to installation. The Midwest CEAC provided services to the Midwest Region that included the states of Illinois, Indiana, Iowa, Kansas, Michigan, Minnesota, Missouri, Nebraska, North Dakota, Ohio, South Dakota, and Wisconsin.

  9. Midwest Transmission Workshop II Summary

    SciTech Connect (OSTI)

    Kevin Bryan

    2002-12-05

    OAK-B135 After introductions of all participants, Abby Arnold, RESOLVE, reviewed the purpose of the meeting and the agenda. The purpose of the workshop was to share the results of the Midwest Independent System Operator (MISO) scenario development for wind and other fuel sources and the corresponding implications for transmission throughout the MISO control area. The workshop agenda is included in Attachment A.

  10. 2nd Annual Midwest Actuarial Student Conference

    E-Print Network [OSTI]

    2014-10-03

    Oct 3, 2014 ... YOU ARE INVITED!! 2nd Annual Midwest Actuarial Student Conference. on the campus of the University of Illinois at Urbana-Champaign.

  11. 2nd Annual Midwest Actuarial Student Conference

    E-Print Network [OSTI]

    Rick Gorvett

    2014-09-16

    1. 2nd Annual Midwest Actuarial Student Conference. University of Illinois at Urbana-?Champaign. Saturday, October 18, 2014. Lincoln Hall – Lincoln Hall ...

  12. INVESTIGATION OF BULK POWER MIDWEST REGION

    E-Print Network [OSTI]

    Laughlin, Robert B.

    INVESTIGATION OF BULK POWER MARKETS MIDWEST REGION November 1, 2000 The analyses and conclusions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-11 1. Bulk Power Prices . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-24 D. Retail Access

  13. Midwest/Mountain Alternative Fuel Initiative | Department of...

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

    MidwestMountain Alternative Fuel Initiative MidwestMountain Alternative Fuel Initiative Presentation from the U.S. DOE Office of Vehicle Technologies "Mega" Merit Review 2008 on...

  14. Coordination of Retail Demand Response with Midwest ISO Markets

    E-Print Network [OSTI]

    Bharvirkar, Ranjit

    2008-01-01

    Robinson, Michael, 2008, "Demand Response in Midwest ISOPresentation at MISO Demand Response Working Group Meeting,Coordination of Retail Demand Response with Midwest ISO

  15. What's happening in Midwest ISO market?

    E-Print Network [OSTI]

    Tesfatsion, Leigh

    What's happening in Midwest ISO market? Review of 2006 Market report for Midwest ISO Department of Presentation Introduction Energy prices in 2006 Day-Ahead Market Performance Real-Time Market Performance Transmission Congestion Details on Day-Ahead Market Details on Real-Time Market Recommendations #12

  16. PACIFIC SOUTHWEST FOREST SERVICE

    E-Print Network [OSTI]

    Columbia, Canada. ACKNOWLEDGMENTS I thank Lula E. Greene, Pacific Southwest Forest and Range Experi ment

  17. Dust around Type Ia supernovae

    E-Print Network [OSTI]

    Wang, Lifan

    2005-01-01

    Dust around Type Ia supernovae Lifan Wang 1,2 LawrenceIa. Subject headings: Supernovae: General, Dust, Extinctionline) bands for Type Ia supernovae. (a), upper panel, shows

  18. Energy Efficiency as a Resource Regional Report: Midwest Region

    SciTech Connect (OSTI)

    Glatt, Sandy; Harry, Ryan; Shields, Garrett

    2010-06-25

    This Industrial Technologies Program report identifies the amount of energy efficiency potential within key manufacturing industries in the Midwest

  19. What's happening in Midwest ISO market?

    E-Print Network [OSTI]

    Tesfatsion, Leigh

    attributable to significantly decreased natural gas, oil and coal prices. (fuel costs represent the vast of Presentation Introduction Energy prices in 2006 Day-Ahead Market Performance Real-Time Market Performance;Introduction 2006 is the first full year of market operations in Midwest ISO. Electricity prices in MISO

  20. 2008 Midwest Levee Failure: Erosion Studies 

    E-Print Network [OSTI]

    Bernhardt, Michelle Lee

    2011-02-22

    of the requirements for the degree of MASTER OF SCIENCE Approved by: Chair of Committee, Jean-Louis Briaud Committee Members, Giovanna Biscontin Russell W. Jessup Head of Department, Mark Burris December 2009 Major Subject: Civil Engineering iii... ABSTRACT 2008 Midwest Levee Failures: Erosion Studies. (December 2009) Michelle Lee Bernhardt, B.S., Texas A&M University Chair of Advisory Committee: Dr. Jean-Louis Briaud The United States contains an estimated 100,000 miles (160000 km...

  1. Midwest Area Chinese American Resources Guide

    E-Print Network [OSTI]

    Chinese American Librarians Association - Midwest Chapter; Wu, Pei-ling; McElroy, Anna; Chang, Ling-li; Sanders, R. Bruce; Lin, Shao-Chen

    1995-01-01

    Copyright 1995 by the Chinese American Librarians Association - Midwest Chapter. All rights reserved. No part of this book may be reproduced. stored, or transmitted by any means without written permission from the publisher. Please send all written..., appointed by the president, include program planning, electronic publishing, nomination, public relations, and special task forces . State contacts are recruited by the vice president. Election usually takes place at the annual meeting held in April or May...

  2. MIDWEST REGIONAL CARBON SEQUESTRATION PARTNERSHIP (MRCSP)

    SciTech Connect (OSTI)

    David Ball; Judith Bradbury; Rattan Lal; Larry Wickstrom; Neeraj Gupta; Robert Burns; Bob Dahowski

    2004-04-30

    This is the first semiannual report for Phase I of the Midwest Carbon Sequestration Partnership (MRCSP). The project consists of nine tasks to be conducted over a two year period that started in October 2003. The makeup of the MRCSP and objectives are described. Progress on each of the active Tasks is also described and where possible, for those Tasks at some point of completion, a summary of results is presented.

  3. Coordination of Retail Demand Response with Midwest ISO Markets

    E-Print Network [OSTI]

    Bharvirkar, Ranjit

    2008-01-01

    2. Wholesale and Retail Electricity Markets in the Midwestwholesale and retail electricity markets. When MISO calledthe wholesale and retail electricity markets in the Midwest

  4. Retail Demand Response in Southwest Power Pool

    E-Print Network [OSTI]

    Bharvirkar, Ranjit

    2009-01-01

    Report Southwest Power Pool,” Prepared by Boston PacificTables Figure 1. Southwest Power Pool Region Footprint and14 Table 1. Southwest Power Pool Membership

  5. Midwest Renewable Energy LLC | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QAsource History ViewMayo, Maryland: Energy ResourcesDec 2005 WindPROLLC Jump to: navigation, search Name: Midwest

  6. EIA - Natural Gas Pipeline System - Midwest Region

    Gasoline and Diesel Fuel Update (EIA)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of Natural GasAdjustments (Billion Cubic Feet) Wyoming963 1.969Central Region About U.S. Natural Gas Pipelines -Midwest Region

  7. Midwest Electric Member Corp | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QA J-E-1 SECTION J APPENDIX ECoop Inc Jump to: navigation,Mereg GmbH Jump to:EC-LEDSMidAmerican EnergyMidvaleMidwest

  8. Midwest Energy Inc | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QA J-E-1 SECTION J APPENDIX ECoop Inc Jump to: navigation,Mereg GmbH Jump to:EC-LEDSMidAmericanMidwest Energy Inc

  9. Midwest Electric, Inc | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QA J-E-1 SECTION J APPENDIXsource HistoryScenariosMarysvilleMicrogravity-Hybrid MicrogravitySizeMiddlesexMidwest

  10. New approaches for modeling type Ia supernovae

    E-Print Network [OSTI]

    Zingale, Michael; Almgren, Ann S.; Bell, John B.; Day, Marcus S.; Rendleman, Charles A.; Woosley, Stan

    2007-01-01

    runaway in Type Ia supernovae: How to run away? oIgnition in Type Ia Supernovae. II. A Three- dimensionalnumber modeling of type Ia supernovae. I. hydrodynamics.

  11. Type Ia Supernovae

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Outreach Home RoomPreservationBio-Inspired SolarAbout /Two Electron Holes in HematiteType Ia Supernovae Type Ia

  12. Midwest Nuclear Science and Engineering Consortium

    SciTech Connect (OSTI)

    Dr. Wynn Volkert; Dr. Arvind Kumar; Dr. Bryan Becker; Dr. Victor Schwinke; Dr. Angel Gonzalez; Dr. DOuglas McGregor

    2010-12-08

    The objective of the Midwest Nuclear Science and Engineering Consortium (MNSEC) is to enhance the scope, quality and integration of educational and research capabilities of nuclear sciences and engineering (NS/E) programs at partner schools in support of the U.S. nuclear industry (including DOE laboratories). With INIE support, MNSEC had a productive seven years and made impressive progress in achieving these goals. Since the past three years have been no-cost-extension periods, limited -- but notable -- progress has been made in FY10. Existing programs continue to be strengthened and broadened at Consortium partner institutions. The enthusiasm generated by the academic, state, federal, and industrial communities for the MNSEC activities is reflected in the significant leveraging that has occurred for our programs.

  13. Coordination of Retail Demand Response with Midwest ISO Markets

    E-Print Network [OSTI]

    Bharvirkar, Ranjit

    2008-01-01

    Data Collection for Demand-side Management for QualifyingPrepared by Demand-side Management Task Force of the4. Status of Demand Side Management in Midwest ISO 5.

  14. Midwest Motor Systems Consortium- A Unique Business Partnership 

    E-Print Network [OSTI]

    Hackner, R.; Cockrill, C.

    1995-01-01

    in the Midwest Motor systems Consortium: the U.S. De partment of Energy; Steven Schultz, 3M; Jim Kelsey and Angela Prestil, Wisconsin Center for Demand Side Research; Sam Mahany Braithwait, Christensen Associates; Ted Atkins, Baldor Electric; Bobbi Mc...

  15. Table HC1-10a. Housing Unit Characteristics by Midwest Census...

    Gasoline and Diesel Fuel Update (EIA)

    0a. Housing Unit Characteristics by Midwest Census Region, Million U.S. Households, 2001 Housing Unit Characteristics RSE Column Factor: Total U.S. Midwest Census Region RSE Row...

  16. Retail Demand Response in Southwest Power Pool

    E-Print Network [OSTI]

    Bharvirkar, Ranjit

    2009-01-01

    and Retails Electricity Markets in SPP The Southwest Powerand Retails Electricity Markets in SPP.3 2.1 Wholesale Markets in the Southwest PowerRetail Demand Response in SPP Wholesale Markets in the Southwest Power

  17. PacificSouthwestResearchStationPrograms Pacific Southwest Research Station

    E-Print Network [OSTI]

    PacificSouthwestResearchStationPrograms Pacific Southwest Research Station Publications List Air Pollution and Global Change Impacts on Western Forest Ecosystems Center for Urban Forest Research Chemical branch of the USDA Forest Service in the states of California and Hawaii and the U.S.-affiliat- ed

  18. Type Ia Supernovae: Spectroscopic Surprises

    E-Print Network [OSTI]

    David Branch

    2003-10-23

    Recent observations have extended the range of diversity among spectra of Type Ia supernovae. I briefly discuss SN Ia explosion models in the spectroscopic context, the observed diversity, and some recent results from direct analysis with the Synow code for one normal and two peculiar SNe Ia. Relating the observational manifestations of diversity to their physical causes is looking like an ever more challenging problem.

  19. A Midwest Regional Inventory of Heavy-Duty Diesel Vehicle Emissions

    E-Print Network [OSTI]

    Wisconsin at Madison, University of

    A Midwest Regional Inventory of Heavy-Duty Diesel Vehicle Emissions by Christopher D. Dresser OF WISCONSIN - MADISON Abstract A Midwest Regional Inventory of Heavy-Duty Diesel Vehicle Emissions Christopher-duty diesel vehicles (HDDV) for a ten-state Midwest region (Mississippi Valley Freight Coalition) using

  20. WETLAND USE AND FEEDING BY LESSER SCAUP DURING SPRING MIGRATION ACROSS THE UPPER MIDWEST, USA

    E-Print Network [OSTI]

    Afton, Alan D.

    bordering the Gulf of Mexico and migrates along the Mississippi River valley and through the upper MidwestWETLAND USE AND FEEDING BY LESSER SCAUP DURING SPRING MIGRATION ACROSS THE UPPER MIDWEST, USA reserves of lesser scaup (Aythya affinis; hereafter scaup) during spring migration in the upper Midwest may

  1. Midwest Appropriate Technology Small Grants Program technical services. Final report

    SciTech Connect (OSTI)

    Not Available

    1984-03-01

    A total of 84 completed projects were reviewed, assessed, and summarized. These projects were also analyzed to determine characteristics of success and failure. Two significant documents resulted: Midwest ATSGP Project Summaries (DOE/CH/10122-19) and Midwest ATSGP Management Analysis (DOE/CH/10122-18). Additionally, 17 active projects were monitored. All grantees were contacted by telephone and 15 sites were visited. Technical assistance was provided to seven of the active grantees. Three grantees were found to be having serious difficulty. Information dissemination activities were limited at DOE-Chicago direction. Presentations at a meeting of state energy agency representatives and the American Solar Energy Society annual meeting were the highlights. Overall, DOE-Chicago was provided important assistance and documentation on the Midwest ATSGP. In addition, several grantees were assisted in the conduct of their project. A complete timetable of activities is included as Appendix E.

  2. Southwest Photovoltaic Systems Inc | Open Energy Information

    Open Energy Info (EERE)

    Southwest Photovoltaic Systems Inc Jump to: navigation, search Name: Southwest Photovoltaic Systems Inc Place: Tomball, Texas Zip: 77375 Product: Distributor of small scale PV...

  3. PACIFIC SOUTHWEST Forest and Range

    E-Print Network [OSTI]

    PACIFIC SOUTHWEST Forest and Range Experiment Station Ash Leachate Can Reduce Surface Erosion leachate can reduce surface erosion. Res. Note PSW-342, 4 p., illus. Pacific Southwest Forest and Range Exp from north- western California, ash leachate flocculated the clay frac- tions. As a result, the soil

  4. IA News Archive

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of Natural GasAdjustmentsShirleyEnergy A plug-inPPLforLDRD Report11,SecurityHome . Form D-4-A Government of the66 IA News

  5. New approaches for modeling type Ia supernovae

    E-Print Network [OSTI]

    Zingale, Michael; Almgren, Ann S.; Bell, John B.; Day, Marcus S.; Rendleman, Charles A.; Woosley, Stan

    2007-01-01

    ich and J. Stein. On the thermonuclear runaway in Type IaSmall-Scale Stability of Thermonuclear Flames o in Type IaS. E. Woosley. The thermonuclear explosion of chandrasekhar

  6. MIE Regional Climate Change Impact Webinar Series: Midwest

    Broader source: Energy.gov [DOE]

    The U.S. Department of Energy's (DOE's) Minorities in Energy Initiative (MIE) is hosting a webinar on midwest impacts of climate change on minority and tribal communities featuring presentations by nationally recognized policymakers, researchers, and educators. Speakers will highlight growing opportunities for workforce development, clean energy advancement, and increases in domestic energy production.

  7. The Midwest Regional Carbon Sequestration Partnership (MRCSP)

    SciTech Connect (OSTI)

    James J. Dooley; Robert Dahowski; Casie Davidson

    2005-12-01

    This final report summarizes the Phase I research conducted by the Midwest regional Carbon Sequestration Partnership (MRCSP). The Phase I effort began in October 2003 and the project period ended on September 31, 2005. The MRCSP is a public/private partnership led by Battelle with the mission of identifying the technical, economic, and social issues associated with implementation of carbon sequestration technologies in its seven state geographic region (Indiana, Kentucky, Maryland, Michigan, Ohio, Pennsylvania, and West Virginia) and identifying viable pathways for their deployment. It is one of seven partnerships that together span most of the U.S. and parts of Canada that comprise the U.S. Department of Energy's (DOE's) Regional Carbon Sequestration Program led by DOE's national Energy Technology Laboratory (NETL). The MRCSP Phase I research was carried out under DOE Cooperative Agreement No. DE-FC26-03NT41981. The total value of Phase I was $3,513,513 of which the DOE share was $2,410,967 or 68.62%. The remainder of the cost share was provided in varying amounts by the rest of the 38 members of MRCSP's Phase I project. The next largest cost sharing participant to DOE in Phase I was the Ohio Coal Development Office within the Ohio Air Quality Development Authority (OCDO). OCDO's contribution was $100,000 and was contributed under Grant Agreement No. CDO/D-02-17. In this report, the MRCSP's research shows that the seven state MRCSP region is a major contributor to the U. S. economy and also to total emissions of CO2, the most significant of the greenhouse gases thought to contribute to global climate change. But, the research has also shown that the region has substantial resources for sequestering carbon, both in deep geological reservoirs (geological sequestration) and through improved agricultural and land management practices (terrestrial sequestration). Geological reservoirs, especially deep saline reservoirs, offer the potential to permanently store CO2 for literally 100s of years even if all the CO2 emissions from the region's large point sources were stored there, an unlikely scenario under any set of national carbon emission mitigation strategies. The terrestrial sequestration opportunities in the region have the biophysical potential to sequester up to 20% of annual emissions from the region's large point sources of CO2. This report describes the assumptions made and methods employed to arrive at the results leading to these conclusions. It also describes the results of analyses of regulatory issues in the region affecting the potential for deployment of sequestration technologies. Finally, it describes the public outreach and education efforts carried out in Phase I including the creation of a web site dedicated to the MRCSP at www.mrcsp.org.

  8. MIDWEST REGIONAL CARBON SEQUESTRATION PARTNERSHIP (MRCSP) MANAGING CLIMATE CHANGE AND SECURING A FUTURE FOR THE MIDWEST'S INDUSTRIAL BASE

    SciTech Connect (OSTI)

    David Ball; Robert Burns; Judith Bradbury; Bob Dahowski; Casie Davidson; James Dooley; Neeraj Gupta; Rattan Lal; Larry Wickstrom

    2005-04-29

    This is the third semiannual report for Phase I of the Midwest Carbon Sequestration Partnership (MRCSP). The project consists of nine tasks to be conducted over a two-year period that started in October 2003. The makeup of the MRCSP and objectives are described. Progress on each of the active Tasks is also described and where possible, for those Tasks at some point of completion, a summary of results is presented.

  9. Type Ia Supernova Explosion Models

    E-Print Network [OSTI]

    W. Hillebrandt; J. C. Niemeyer

    2000-06-21

    Because calibrated light curves of Type Ia supernovae have become a major tool to determine the local expansion rate of the Universe and also its geometrical structure, considerable attention has been given to models of these events over the past couple of years. There are good reasons to believe that perhaps most Type Ia supernovae are the explosions of white dwarfs that have approached the Chandrasekhar mass, M_ch ~ 1.39 M_sun, and are disrupted by thermonuclear fusion of carbon and oxygen. However, the mechanism whereby such accreting carbon-oxygen white dwarfs explode continues to be uncertain. Recent progress in modeling Type Ia supernovae as well as several of the still open questions are addressed in this review. Although the main emphasis will be on studies of the explosion mechanism itself and on the related physical processes, including the physics of turbulent nuclear combustion in degenerate stars, we also discuss observational constraints.

  10. Turbulence-Flame Interactions in Type Ia Supernovae

    E-Print Network [OSTI]

    Aspden, Andrew J; Lawrence Berkeley National Laboratory, 1 Cyclotron Road, MS 50A-1148, Berkeley, CA 94720 (Authors 1, 2 & 3); Department of Astronomy and Astrophysics, University of California at Santa Cruz, Santa Cruz, CA 95064 (Author 4); Department of Physics and Astronomy, Stony Brook University, Stony Brook, NY 11794 (Author 5)

    2008-01-01

    Interactions in Type Ia Supernovae A. J. Aspden 1 , J. B.involved in type Ia supernovae (SN Ia) requires the use of ?generated by RT in type Ia supernovae should obey Bolgiano-

  11. PACIFIC SOUTHWEST Forest and Range

    E-Print Network [OSTI]

    of forest stands is valuable for studies of the physical environment. Energy balance research centers on howPACIFIC SOUTHWEST Forest and Range Experiment Station FOREST SERVICE U.S. DEPARTMENT in relation to climatic and stand variables USDA FOREST SERVICE RESEARCH PAPER PSW- 71 /1971 #12;CONTENTS

  12. Defining photometric peculiar type Ia supernovae

    SciTech Connect (OSTI)

    González-Gaitán, S.; Pignata, G.; Förster, F.; Gutiérrez, C. P.; Bufano, F.; Galbany, L.; Hamuy, M.; De Jaeger, T. [Millennium Institute of Astrophysics, Casilla 36-D, Santiago (Chile); Hsiao, E. Y.; Phillips, M. M. [Carnegie Observatories, Las Campanas Observatory, Casilla 601, La Serena (Chile); Folatelli, G. [Kavli Institute for the Physics and Mathematics of the Universe, the University of Tokyo, Kashiwa 277-8583 (Kavli IPMU, WPI) (Japan); Anderson, J. P., E-mail: sgonzale@das.uchile.cl [European Southern Observatory, Alonso de Córdova 3107, Casilla 19, Santiago (Chile)

    2014-11-10

    We present a new photometric identification technique for SN 1991bg-like type Ia supernovae (SNe Ia), i.e., objects with light curve characteristics such as later primary maxima and the absence of a secondary peak in redder filters. This method is capable of selecting this sub-group from the normal type Ia population. Furthermore, we find that recently identified peculiar sub-types such as SNe Iax and super-Chandrasekhar SNe Ia have photometric characteristics similar to 91bg-like SNe Ia, namely, the absence of secondary maxima and shoulders at longer wavelengths, and can also be classified with our technique. The similarity of these different SN Ia sub-groups perhaps suggests common physical conditions. This typing methodology permits the photometric identification of peculiar SNe Ia in large upcoming wide-field surveys either to study them further or to obtain a pure sample of normal SNe Ia for cosmological studies.

  13. Ideal bandpasses for type Ia supernova cosmology

    E-Print Network [OSTI]

    Davis, Tamara M.; Schmidt, Brian P.; Kim, Alex G.

    2005-01-01

    diversity of type Ia Supernovae, in preparation. Kim, A.error in measurements of supernovae depends on a periodicABSTRACT To use type Ia supernovae as standard candles for

  14. Rates and progenitors of type Ia supernovae

    E-Print Network [OSTI]

    Wood-Vasey, William Michael

    2004-01-01

    Supernovae . . . . . . . . . . . . . . . . . . . .Supernovae Found 5.1 Introduction . . . . . . . . . . . .1.2 Non-Type Ia Supernovae . . . . . . . . . . . . . . . 1.3

  15. Type Ia Supernovae: Toward the Standard Model?

    E-Print Network [OSTI]

    David Branch

    2000-12-13

    In this short review I suggest that recent developments support the conjecture that Type Ia supernovae (SNe Ia) are the complete disruptions of Chandrasekhar-mass carbon-oxygen white dwarfs in single-degenerate binary systems. The causes of the observational diversity of SNe Ia within the context of this standard model, and the implications of the model for young remnants of SNe Ia, are briefly discussed.

  16. Midwest Region Underground Natural Gas Storage - All Operators

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home PageMonthly","10/2015"4,"Ames5 Tables July 1996 Energy Information Administration Office of Coal, Nuclear,Decade Year-03.82 4.235,382Year526)Midwest Region

  17. Midwest Region Natural Gas Working Underground Storage (Billion Cubic Feet)

    Gasoline and Diesel Fuel Update (EIA)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of Natural GasAdjustments (Billion Cubic Feet) Wyoming963Residential2, 2014 MEMORANDUMProvedFeet) U.S. Energy87Midwest

  18. Midwest Regions Natural Gas Underground Storage Net Withdrawals (Million

    Gasoline and Diesel Fuel Update (EIA)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of Natural GasAdjustments (Billion Cubic Feet) Wyoming963Residential2, 2014 MEMORANDUMProvedFeet) U.S. Energy87MidwestCubic

  19. Midwest Energy Inc. Smart Grid Project | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QA J-E-1 SECTION J APPENDIX ECoop Inc Jump to: navigation,Mereg GmbH Jump to:EC-LEDSMidAmericanMidwest Energy

  20. Midwest Independent Transmission System Operator Smart Grid Project | Open

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QA J-E-1 SECTION J APPENDIX ECoop Inc Jump to: navigation,Mereg GmbH Jump to:EC-LEDSMidAmericanMidwest EnergyEnergy

  1. Midwest States Save Energy Now Partnership Program | Department of Energy

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of Natural GasAdjustmentsShirleyEnergyTher i nAand DOE SafetyofDepartment. "National MidcourseEnergyMidwest

  2. Upper Midwest Hydrogen Initiative UMHI | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QA J-E-1 SECTION JEnvironmental Jump to:EA EISTJThin FilmUnited States: EnergyUpper Cumberland E M C Jump to:Midwest

  3. Type Ia Supernova Carbon Footprints

    E-Print Network [OSTI]

    Thomas, R C; Aragon, C; Antilogus, P; Bailey, S; Baltay, C; Bongard, S; Buton, C; Canto, A; Childress, M; Chotard, N; Copin, Y; Fakhouri, H K; Gangler, E; Hsiao, E Y; Kerschhaggl, M; Kowalski, M; Loken, S; Nugent, P; Paech, K; Pain, R; Pecontal, E; Pereira, R; Perlmutter, S; Rabinowitz, D; Rigault, M; Rubin, D; Runge, K; Scalzo, R; Smadja, G; Tao, C; Weaver, B A; Wu, C; Brown, P J; Milne, P A

    2011-01-01

    We present convincing evidence of unburned carbon at photospheric velocities in new observations of 5 Type Ia supernovae (SNe Ia) obtained by the Nearby Supernova Factory. These SNe are identified by examining 346 spectra from 124 SNe obtained before +2.5 d relative to maximum. Detections are based on the presence of relatively strong C II 6580 absorption "notches" in multiple spectra of each SN, aided by automated fitting with the SYNAPPS code. Four of the 5 SNe in question are otherwise spectroscopically unremarkable, with ions and ejection velocities typical of SNe Ia, but spectra of the fifth exhibits high-velocity (v > 20,000 km/s) Si II and Ca II features. On the other hand, the light curve properties are preferentially grouped, strongly suggesting a connection between carbon-positivity and broad band light curve/color behavior: Three of the 5 have relatively narrow light curves but also blue colors, and a fourth may be a dust-reddened member of this family. Accounting for signal-to-noise and phase, we ...

  4. Southwest Electric Cooperative- Energy Efficiency Rebate Program

    Broader source: Energy.gov [DOE]

    Southwest Electric Cooperative offers rebates to its customers that purchase energy efficient heating and air conditioning equipment . This program offers rebates for customers who buy Energy Star...

  5. Low Mach Number Modeling of Type Ia Supernovae. II. Energy Evolution

    E-Print Network [OSTI]

    Almgren, Ann S.; Bell, John B.; Rendleman, Charles A.; Zingale, Mike

    2006-01-01

    Number Modeling of Type Ia Supernovae. II. Energy EvolutionIa. Subject headings: supernovae: general — white dwarfs —the ignition of Type Ia supernovae (SNe Ia) is critical to

  6. Turbulent Combustion in Type Ia Supernova Models

    E-Print Network [OSTI]

    F. K. Roepke; W. Hillebrandt

    2006-09-15

    We review the astrophysical modeling of type Ia supernova explosions and describe numerical methods to implement numerical simulations of these events. Some results of such simulations are discussed.

  7. Fact #756: December 3, 2012 Midwest Produces Two-Thirds of All Light Vehicles

    Broader source: Energy.gov [DOE]

    Although there are many new vehicle assembly plants located in the South, the Midwest region continues to produce about two-thirds of all light vehicles. The year 2009 was the low point for vehicle...

  8. KAir Battery Wins Southwest Regional Clean Energy Business Plan...

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

    KAir Battery Wins Southwest Regional Clean Energy Business Plan Competition KAir Battery Wins Southwest Regional Clean Energy Business Plan Competition April 18, 2014 - 12:05pm...

  9. Southwest

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power AdministrationRobust,Field-effect Photovoltaics -7541C. TemperatureThousand Cubic Feet)Investment insay

  10. Southwest

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power AdministrationRobust,Field-effect Photovoltaics -7541C. TemperatureThousand Cubic Feet)Investment

  11. Southwest

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of Natural GasAdjustmentsShirley Ann JacksonDepartment ofOffice|inWestMayBuilding K-25Kyle Travis, left andInvestment in

  12. IA-32 Intel Architecture Software Developer's

    E-Print Network [OSTI]

    Bernstein, Daniel

    IA-32 Intel® Architecture Software Developer's Manual Volume 1: Basic Architecture NOTE: The IA-32 Intel Architecture Software Developer's Manual consists of four volumes: Basic Architecture, Order RIGHT. INTEL PRODUCTS ARE NOT INTENDED FOR USE IN MEDICAL, LIFE SAVING, OR LIFE SUSTAINING APPLICATIONS

  13. IA-32 Intel Architecture Software Developer's

    E-Print Network [OSTI]

    IA-32 Intel® Architecture Software Developer's Manual Volume 3: System Programming Guide NOTE: The IA-32 Intel Architecture Developer's Manual consists of three books: Basic Architecture, Order Number SAVING, OR LIFE SUSTAINING APPLICATIONS. Intel may make changes to specifications and product

  14. ASTRONOMY AND ASTROPHYSICS Dark Energy, Type Ia supernovae, radiative

    Office of Scientific and Technical Information (OSTI)

    of Oklahoma Univ. of Oklahoma 79 ASTRONOMY AND ASTROPHYSICS Dark Energy, Type Ia supernovae, radiative transfer, Dark Energy, Type Ia supernovae, radiative transfer, The...

  15. Coordination of Retail Demand Response with Midwest ISO Markets

    SciTech Connect (OSTI)

    Bharvirkar, Ranjit; Bharvirkar, Ranjit; Goldman, Charles; Heffner, Grayson; Sedano, Richard

    2008-05-27

    The Organization of Midwest ISO States (OMS) launched the Midwest Demand Resource Initiative (MWDRI) in 2007 to identify barriers to deploying demand response (DR) resources in the Midwest Independent System Operator (MISO) region and develop policies to overcome them. The MWDRI stakeholders decided that a useful initial activity would be to develop more detailed information on existing retail DR programs and dynamic pricing tariffs, program rules, and utility operating practices. This additional detail could then be used to assess any"seams issues" affecting coordination and integration of retail DR resources with MISO's wholesale markets. Working with state regulatory agencies, we conducted a detailed survey of existing DR programs, dynamic pricing tariffs, and their features in MISO states. Utilities were asked to provide information on advance notice requirements to customers, operational triggers used to call events (e.g. system emergencies, market conditions, local emergencies), use of these DR resources to meet planning reserves requirements, DR resource availability (e.g., seasonal, annual), participant incentive structures, and monitoring and verification (M&V) protocols. This report describes the results of this comprehensive survey and discusses policy implications for integrating legacy retail DR programs and dynamic pricing tariffs into organized wholesale markets. Survey responses from 37 MISO members and 4 non-members provided information on 141 DR programs and dynamic pricing tariffs with a peak load reduction potential of 4,727 MW of retail DR resource. Major findings of this study area:- About 72percent of available DR is from interruptible rate tariffs offered to large commercial and industrial customers, while direct load control (DLC) programs account for ~;;18percent. Almost 90percent of the DR resources included in this survey are provided by investor-owned utilities. - Approximately, 90percent of the DR resources are available with less than two hours advance notice and over 1,900 MW can be dispatched on less than thirty minutes notice. These legacy DR programs are increasingly used by utilities for economic in addition to reliability purposes, with over two-thirds (68percent) of these programs callable based on market conditions. - Approximately 60percent of DLC programs and 30percent of interruptible rate programs called ten or more DR events in 2006. Despite the high frequency of DR events, customer complaints remained low. The use of economic criteria to trigger DR events and the flexibility to trigger a large number of events suggests that DR resources can help improve the efficiency of MISO wholesale markets. - Most legacy DR programs offered a reservation payment ($/kW) for participation; incentive payment levels averaged about $5/kW-month for interruptible rate tariffs and $6/kW-month for DLC programs. Few programs offered incentive payments that were explicitly linked to actual load reductions during events and at least 27 DR programs do not have penalties for non-performance. - Measurement and verification (M&V) protocols to estimate load impacts vary significantly across MISO states. Almost half of the DR programs have not been evaluated in recent times and thus performance data for DR events is not available. For many DLC programs, M&V protocols may need to be enhancedin order to allow participation in MISO's proposed EDR schedule. System operators and planners will need to develop more accurate estimates of the load reduced capability and actual performance.

  16. Three-dimensional Numerical Simulations of Rayleigh-Taylor Unstable Flames in Type Ia Supernovae

    E-Print Network [OSTI]

    Bell, John B.

    ) instability and turbulence in accelerating a thermonuclear flame in Type Ia supernovae (SNe Ia) is well

  17. Threatened and endangered fish and wildlife of the midwest

    SciTech Connect (OSTI)

    Schafer, D.W.; Robeck, K.E.

    1980-06-01

    This report contains information of federally-listed endangered and/or threatened fish and wildlife occurring in the midwestern states of Illinois, Indiana, Iowa, Kansas, Michigan, Minnesota, Missouri, Nebraska, Ohio, and Wisconsin. The information was compiled as a support document for the Regional Issue Identification and Assessment (RIIA) project sponsored by the Regional Assessments Division of the Office of Technology Impacts within the Department of Energy. The information on midwestern endangered species distribution, habitats, and reasons for population decline included in this document are designed to help assess the potential for adverse impacts if energy activities are sited within the general range of an endangered species. It is hoped that this document will thereby enhance the reliability of one portion of energy-related assessments performed in the Midwest. This report considers only those species listed prior to October 1979 as endangered and/or threatened in the federal endangered species list published in the Federal Register and that have been known to occur in the region in the last 20 years.

  18. SunZia Southwest Transmission Project Comments

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

    of March 28, 2012 2 1.0 Background. SunZia Southwest Transmission Project (SunZia or the Project) is a joint development effort currently underway in Arizona and New Mexico. The...

  19. 2010 Municipal Consortium Southwest Region Workshop Materials

    Broader source: Energy.gov [DOE]

    This page provides links to the presentations given at the DOE Municipal Solid-State Street Lighting Consortium Southwest Region Workshop, held in Los Angeles on September 30, 2010.

  20. 2011 Municipal Consortium Southwest Region Workshop Materials

    Broader source: Energy.gov [DOE]

    This page provides links to the presentations given at the DOE Municipal Solid-State Street Lighting Consortium Southwest Region Workshop, held in San Jose, California, August 25­–26, 2011.

  1. SNe Ia as a cosmological probe

    E-Print Network [OSTI]

    Meng, Xiangcun; Han, Zhanwen

    2015-01-01

    Type Ia supernovae luminosities can be corrected to render them useful as standard candles able to probe the expansion history of the universe. This technique was successful applied to discover the present acceleration of the universe. As the number of SNe Ia observed at high redshift increases and analysis techniques are perfected, people aim to use this technique to probe the equation of state of the dark energy. Nevertheless, the nature of SNe Ia progenitors remains controversial and concerns persist about possible evolution effects that may be larger and harder to characterize than the more obvious statistical uncertainties.

  2. MIDWEST ISO CO-OPTIMIZATION BASED REAL-TIME DISPATCH AND PRICING OF ENERGY AND ANCILLARY SERVICES

    E-Print Network [OSTI]

    McCalley, James D.

    MIDWEST ISO CO-OPTIMIZATION BASED REAL-TIME DISPATCH AND PRICING OF ENERGY AND ANCILLARY SERVICES and ancillary service co-optimization is reported in this paper. The key components of Midwest ISO's real words ­ Real-time dispatch and pricing, LMP, Energy and ancillary service co-optimization, Intra

  3. Type Ia Supernovae Project at NERSC

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

    of star called a white dwarf. The majority of SN Ia explosions occur far away from our galaxy; yet, due to their enormous intrinsic brightness, outshining billions of stars, we can...

  4. Type Ia Supernovae and the Hubble Constant

    E-Print Network [OSTI]

    D. Branch

    1998-01-08

    The focus of this review is the work that has been done during the 1990s on using Type Ia supernovae (SNe Ia) to measure the Hubble constant ($H_0$). SNe Ia are well suited for measuring $H_0$. A straightforward maximum-light color criterion can weed out the minority of observed events that are either intrinsically subluminous or substantially extinguished by dust, leaving a majority subsample that has observational absolute-magnitude dispersions of less than $\\sigma_{obs}(M_B) \\simeq \\sigma_{obs}(M_V) \\simeq 0.3$ mag. Correlations between absolute magnitude and one or more distance-independent SN Ia or parent-galaxy observables can be used to further standardize the absolute magnitudes to better than 0.2 mag. The absolute magnitudes can be calibrated in two independent ways --- empirically, using Cepheid-based distances to parent galaxies of SNe Ia, and physically, by light curve and spectrum fitting. At present the empirical and physical calibrations are in agreement at $M_B \\simeq M_V \\simeq -19.4$ or -19.5. Various ways that have been used to match Cepheid-calibrated SNe Ia or physical models to SNe Ia that have been observed out in the Hubble flow have given values of $H_0$ distributed throughout the range 54 to 67 km/s Mpc$^{-1}$. Astronomers who want a consensus value of $H_0$ from SNe Ia with conservative errors could, for now, use $60 \\pm 10$ km/s Mpc^{-1}$.

  5. Nucleosynthesis in Type Ia Supernovae

    E-Print Network [OSTI]

    K. Nomoto; K. Iwamoto; N. Nakasato; F. -K. Thielemann; F. Brachwitz; T. Tsujimoto; Y. Kubo; N. Kishimoto

    1997-06-03

    Among the major uncertainties involved in the Chandrasekhar mass models for Type Ia supernovae are the companion star of the accreting white dwarf (or the accretion rate that determines the carbon ignition density) and the flame speed after ignition. We present nucleosynthesis results from relatively slow deflagration (1.5 - 3 % of the sound speed) to constrain the rate of accretion from the companion star. Because of electron capture, a significant amount of neutron-rich species such as ^{54}Cr, ^{50}Ti, ^{58}Fe, ^{62}Ni, etc. are synthesized in the central region. To avoid the too large ratios of ^{54}Cr/^{56}Fe and ^{50}Ti/^{56}Fe, the central density of the white dwarf at thermonuclear runaway must be as low as \\ltsim 2 \\e9 \\gmc. Such a low central density can be realized by the accretion as fast as $\\dot M \\gtsim 1 \\times 10^{-7} M_\\odot yr^{-1}$. These rapidly accreting white dwarfs might correspond to the super-soft X-ray sources.

  6. Rates and progenitors of type Ia supernovae

    SciTech Connect (OSTI)

    Wood-Vasey, William Michael

    2004-08-16

    The remarkable uniformity of Type Ia supernovae has allowed astronomers to use them as distance indicators to measure the properties and expansion history of the Universe. However, Type Ia supernovae exhibit intrinsic variation in both their spectra and observed brightness. The brightness variations have been approximately corrected by various methods, but there remain intrinsic variations that limit the statistical power of current and future observations of distant supernovae for cosmological purposes. There may be systematic effects in this residual variation that evolve with redshift and thus limit the cosmological power of SN Ia luminosity-distance experiments. To reduce these systematic uncertainties, we need a deeper understanding of the observed variations in Type Ia supernovae. Toward this end, the Nearby Supernova Factory has been designed to discover hundreds of Type Ia supernovae in a systematic and automated fashion and study them in detail. This project will observe these supernovae spectrophotometrically to provide the homogeneous high-quality data set necessary to improve the understanding and calibration of these vital cosmological yardsticks. From 1998 to 2003, in collaboration with the Near-Earth Asteroid Tracking group at the Jet Propulsion Laboratory, a systematic and automated searching program was conceived and executed using the computing facilities at Lawrence Berkeley National Laboratory and the National Energy Research Supercomputing Center. An automated search had never been attempted on this scale. A number of planned future large supernovae projects are predicated on the ability to find supernovae quickly, reliably, and efficiently in large datasets. A prototype run of the SNfactory search pipeline conducted from 2002 to 2003 discovered 83 SNe at a final rate of 12 SNe/month. A large, homogeneous search of this scale offers an excellent opportunity to measure the rate of Type Ia supernovae. This thesis presents a new method for analyzing the true sensitivity of a multi-epoch supernova search and finds a Type Ia supernova rate from z {approx} 0.01-0.1 of r{sub V} = 4.26{sub -1.93 -0.10}{sup +1.39 +0.10} h{sup 3} x 10{sup -4} SNe Ia/yr/Mpc{sup 3} from a preliminary analysis of a subsample of the SNfactory prototype search. Several unusual supernovae were found in the course of the SNfactory prototype search. One in particular, SN 2002ic, was the first SN Ia to exhibit convincing evidence for a circumstellar medium and offers valuable insight into the progenitors of Type Ia supernovae.

  7. Type Ia Supernova Intrinsic Magnitude Dispersion and the Fitting of Cosmological Parameters

    E-Print Network [OSTI]

    Kim, Alex G

    2011-01-01

    Applied to Type Ia supernovae, my strategy provides adata sets. Subject headings: Supernovae: Data Analysis andhomogeneous nature of Type Ia supernovae (SNe Ia) makes them

  8. Verifying the Cosmological Utility of Type Ia Supernovae: Implications of a Dispersion in the Ultraviolet Spectra

    E-Print Network [OSTI]

    Ellis, R. S.

    2008-01-01

    Utility of Type Ia Supernovae: Implications of a Dispersionheadings: surveys – supernovae: general – cosmologicalparameters Introduction Supernovae of Type Ia (SNe Ia) are

  9. SOUTHWEST REGIONAL PARTNERSHIP ON CARBON SEQUESTRATION

    SciTech Connect (OSTI)

    Brian McPherson; Rick Allis; Barry Biediger; Joel Brown; Jim Cappa; George Guthrie; Richard Hughes; Eugene Kim; Robert Lee; Dennis Leppin; Charles Mankin; Orman Paananen; Rajesh Pawar; Tarla Peterson; Steve Rauzi; Jerry Stuth; Genevieve Young

    2004-11-01

    The Southwest Partnership Region includes six whole states, including Arizona, Colorado, Kansas, New Mexico, Oklahoma, and Utah, roughly one-third of Texas, and significant portions of adjacent states. The Partnership comprises a large, diverse group of expert organizations and individuals specializing in carbon sequestration science and engineering, as well as public policy and outreach. The main objective of the Southwest Partnership project is to achieve an 18% reduction in carbon intensity by 2012. The Partnership made great progress in this first year. Action plans for possible Phase II carbon sequestration pilot tests in the region are almost finished, including both technical and non-technical aspects necessary for developing and carrying out these pilot tests. All partners in the Partnership are taking an active role in evaluating and ranking optimum sites and technologies for capture and storage of CO{sub 2} in the Southwest Region. We are identifying potential gaps in all aspects of potential sequestration deployment issues.

  10. Trophic understanding of tunas of the Southwest Pacific Ocean

    E-Print Network [OSTI]

    Hawai'i at Manoa, University of

    Working Group 3) · Trophic ecology · Chemical indicators · Bioenergetics · Niche separation · Climate indicators Bioenergetics Niche separation Climate change 7 | Trophic understanding of tunas of the Southwest of tunas of the Southwest Pacific Ocean Trophic ecology Chemical indicators Bioenergetics Niche separation

  11. The role of energy storage in accessing remote wind resources in the Midwest

    E-Print Network [OSTI]

    Jaramillo, Paulina

    The role of energy storage in accessing remote wind resources in the Midwest Julian Lamy n , Inês L of energy storage to replace transmission. We focus on a wind farm in North Dakota that must deliver power to Illinois. Energy storage capital costs must be less than $100/kW h. Transmission capital costs must

  12. In Oklahoma and other parts of the Midwest, gasoline prices have been

    E-Print Network [OSTI]

    Balasundaram, Balabhaskar "Baski"

    FALL 2013 10 In Oklahoma and other parts of the Midwest, gasoline prices have been skyrocketing this year. And as gas prices go, so go the prices for just about every- thing else, boosting the general be converted with chemical catalysts to produce renewable gasoline, diesel and jet fuels. "We are advancing

  13. SOUTHWEST REGIONAL PARTNERSHIP ON CARBON SEQUESTRATION

    SciTech Connect (OSTI)

    Brian McPherson

    2005-08-01

    The Southwest Partnership on Carbon Sequestration completed several more tasks during the period of October 1, 2004--March 31, 2005. The main objective of the Southwest Partnership project is to achieve an 18% reduction in carbon intensity by 2012. Action plans for possible Phase 2 carbon sequestration pilot tests in the region are completed, and a proposal was developed and submitted describing how the Partnership may develop and carry out appropriate pilot tests. The content of this report focuses on Phase 1 objectives completed during this reporting period.

  14. Trophic understanding of tunas of the Southwest Pacific Ocean

    E-Print Network [OSTI]

    Hawai'i at Manoa, University of

    Trophic understanding of tunas of the Southwest Pacific Ocean WEALTH FROM OCEANS FLAGSHIP Jock of tunas of the Southwest Pacific Ocean| JWY3 | Thunnus tonggol Thunnus obesus Thunnus albacares Thunnus of the Southwest Pacific Ocean| JWY4 | Species SCA DR SIA SFA Thunnus alalunga + + + 0 Thunnus albacares + + + 0

  15. Neutronization During Type Ia Supernova Simmering

    E-Print Network [OSTI]

    Piro, Anthony L

    2007-01-01

    Prior to the incineration of a white dwarf (WD) that makes a Type Ia supernova (SN Ia), the star "simmers" for ~1000 years in a convecting, carbon burning region. We have found that weak interactions during this time increase the neutron excess by an amount that depends on the total quantity of carbon burned prior to the explosion. This contribution is in addition to the metallicity (Z) dependent neutronization through the 22Ne abundance (as studied by Timmes, Brown, & Truran). The main consequence is that we expect a floor to the level of neutronization that dominates over the metallicity contribution when Z/Z_\\odot<2/3, and it can be important for even larger metallicities if substantial energy is lost to neutrinos via the convective Urca process. This would mask any correlations between SN Ia properties and galactic environments at low metallicities. In addition, we show that recent observations of the dependences of SNe Ia on galactic environments make it clear that metallicity alone cannot provide...

  16. Neutronization During Type Ia Supernova Simmering

    E-Print Network [OSTI]

    Anthony L. Piro; Lars Bildsten

    2007-10-08

    Prior to the incineration of a white dwarf (WD) that makes a Type Ia supernova (SN Ia), the star "simmers" for ~1000 years in a convecting, carbon burning region. We have found that weak interactions during this time increase the neutron excess by an amount that depends on the total quantity of carbon burned prior to the explosion. This contribution is in addition to the metallicity (Z) dependent neutronization through the 22Ne abundance (as studied by Timmes, Brown, & Truran). The main consequence is that we expect a floor to the level of neutronization that dominates over the metallicity contribution when Z/Z_\\odot<2/3, and it can be important for even larger metallicities if substantial energy is lost to neutrinos via the convective Urca process. This would mask any correlations between SN Ia properties and galactic environments at low metallicities. In addition, we show that recent observations of the dependences of SNe Ia on galactic environments make it clear that metallicity alone cannot provide for the full observed diversity of events.

  17. Southwest Regional Partnership on Carbon Sequestration

    SciTech Connect (OSTI)

    Brian McPherson

    2006-03-31

    The Southwest Partnership on Carbon Sequestration completed its Phase I program in December 2005. The main objective of the Southwest Partnership Phase I project was to evaluate and demonstrate the means for achieving an 18% reduction in carbon intensity by 2012. Many other goals were accomplished on the way to this objective, including (1) analysis of CO{sub 2} storage options in the region, including characterization of storage capacities and transportation options, (2) analysis and summary of CO{sub 2} sources, (3) analysis and summary of CO{sub 2} separation and capture technologies employed in the region, (4) evaluation and ranking of the most appropriate sequestration technologies for capture and storage of CO{sub 2} in the Southwest Region, (5) dissemination of existing regulatory/permitting requirements, and (6) assessing and initiating public knowledge and acceptance of possible sequestration approaches. Results of the Southwest Partnership's Phase I evaluation suggested that the most convenient and practical ''first opportunities'' for sequestration would lie along existing CO{sub 2} pipelines in the region. Action plans for six Phase II validation tests in the region were developed, with a portfolio that includes four geologic pilot tests distributed among Utah, New Mexico, and Texas. The Partnership will also conduct a regional terrestrial sequestration pilot program focusing on improved terrestrial MMV methods and reporting approaches specific for the Southwest region. The sixth and final validation test consists of a local-scale terrestrial pilot involving restoration of riparian lands for sequestration purposes. The validation test will use desalinated waters produced from one of the geologic pilot tests. The Southwest Regional Partnership comprises a large, diverse group of expert organizations and individuals specializing in carbon sequestration science and engineering, as well as public policy and outreach. These partners include 21 state government agencies and universities, five major electric utility companies, seven oil, gas and coal companies, three federal agencies, the Navajo Nation, several NGOs, and the Western Governors Association. This group is continuing its work in the Phase II Validation Program, slated to conclude in 2009.

  18. The contribution of future agricultural trends in the US Midwest to global climate change mitigation

    SciTech Connect (OSTI)

    Thomson, Allison M.; Kyle, G. Page; Zhang, Xuesong; Bandaru, Varaprasad; West, Tristram O.; Wise, Marshall A.; Izaurralde, Roberto C.; Calvin, Katherine V.

    2014-01-19

    Land use change is a complex response to changing environmental and socioeconomic systems. Historical drivers of land use change include changes in the natural resource availability of a region, changes in economic conditions for production of certain products and changing policies. Most recently, introduction of policy incentives for biofuel production have influenced land use change in the US Midwest, leading to concerns that bioenergy production systems may compete with food production and land conservation. Here we explore how land use may be impacted by future climate mitigation measures by nesting a high resolution agricultural model (EPIC – Environmental Policy Indicator Climate) for the US Midwest within a global integrated assessment model (GCAM – Global Change Assessment Model). This approach is designed to provide greater spatial resolution and detailed agricultural practice information by focusing on the climate mitigation potential of agriculture and land use in a specific region, while retaining the global economic context necessary to understand the far ranging effects of climate mitigation targets. We find that until the simulated carbon prices are very high, the US Midwest has a comparative advantage in producing traditional food and feed crops over bioenergy crops. Overall, the model responds to multiple pressures by adopting a mix of future responses. We also find that the GCAM model is capable of simulations at multiple spatial scales and agricultural technology resolution, which provides the capability to examine regional response to global policy and economic conditions in the context of climate mitigation.

  19. IA News Archive | Department of Energy

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Delicious Rank EERE: Alternative Fuelsof Energy ServicesContractingManagement »Hydrogen andBlog Archive IA

  20. Time-Domain Electromagnetics At Kilauea Southwest Rift And South...

    Open Energy Info (EERE)

    Details Location Kilauea Southwest Rift And South Flank Area Exploration Technique Time-Domain Electromagnetics Activity Date Usefulness useful DOE-funding Unknown Notes The...

  1. Retail Demand Response in Southwest Power Pool | Department of...

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

    for integrating legacy retail DR programs and dynamic pricing tariffs into wholesale markets in the SPP region. Retail Demand Response in Southwest Power Pool More Documents &...

  2. Direct-Current Resistivity Survey At Mauna Loa Southwest Rift...

    Open Energy Info (EERE)

    Direct-Current Resistivity Survey At Mauna Loa Southwest Rift Area (Thomas, 1986) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Direct-Current...

  3. Teleseismic-Seismic Monitoring At Kilauea Southwest Rift And...

    Open Energy Info (EERE)

    Teleseismic-Seismic Monitoring At Kilauea Southwest Rift And South Flank Area (Wyss, Et Al., 2001) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration...

  4. Cultural Geography and Interregional Contacts in Prehistoric Liangshan (Southwest China)

    E-Print Network [OSTI]

    Hein, Anke Marion

    2013-01-01

    George 2005. Physical Geography of the Gaoligong Shan Areaof China's Physical Geography. China Knowledge Series.shou Sun. 1962. Economic Geography of Southwest China : (

  5. EIA - Natural Gas Pipeline System - Southwest Region

    Gasoline and Diesel Fuel Update (EIA)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of Natural GasAdjustments (Billion Cubic Feet) Wyoming963 1.969Central Region About U.S. Natural Gas PipelinesSouthwest Region

  6. Southwest Mesa Wind Farm | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QA J-E-1 SECTION JEnvironmental Jump to:EA EIS ReportEurope GmbHSoloPage Edit with form History Southwest Arkansas

  7. Southwest Wind Power | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QA J-E-1 SECTION JEnvironmental Jump to:EA EIS ReportEurope GmbHSoloPage Edit with form History Southwest

  8. INTRODUCCI ON A LA GEOMETR IA DIFERENCIAL 1

    E-Print Network [OSTI]

    Gràcia, Xavier

    .009 Zaragoza (ESPA ~ NA) Typeset by A M S-T E X 1 #12; 2 INTRODUCCI #19; ON A LA GEOMETR #19; IA DIFERENCIAL

  9. K-corrections and spectral templates of Type Ia supernovae

    E-Print Network [OSTI]

    Hsiao, E. Y.

    2008-01-01

    templates of Type Ia supernovae E. Y. Hsiao 1 , A. Conleyobservations of low-redshift supernovae are less a?ected byobservations, stars: supernovae Department of Physics and

  10. Type Ia Supernova Hubble Residuals and Host-Galaxy Properties

    E-Print Network [OSTI]

    Kim, A. G.

    2014-01-01

    magnitudes of type Ia supernovae from multi-band lightsuch an analysis on the supernovae of the Nearby Supernovaheadings: distance scale, supernovae: general 1 Physics

  11. Comments of the Independent Peer-Review Team for the Interim Regional Supplement to the Corps of Engineers Wetland Delineation Manual: Midwest Region

    E-Print Network [OSTI]

    US Army Corps of Engineers

    of Engineers Wetland Delineation Manual: Midwest Region Submitted August 10, 2007 Initials: Reviewer: HC Norman, Frank, PWS Development Center (ERDC) and the Midwest Working Group are JP Pagliara, Joe, PWS. Recommend replacing "abundant" with "adequate" or add "with periodic or prolonged wet periods or droughts

  12. IA News Archive | Department of Energy

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of Natural GasAdjustmentsShirleyEnergy A plug-inPPLforLDRD Report11,SecurityHome . Form D-4-A Government of the66 IA

  13. IA Experts Listing 2014 | Department of Energy

    Energy Savers [EERE]

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on DeliciousMathematicsEnergy HeadquartersFuelB IMSofNewsletterGuidingUpdateof EnergyDepartment of EnergyIA

  14. IA Blog Archive | Department of Energy

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Delicious Rank EERE: Alternative Fuelsof Energy ServicesContractingManagement »Hydrogen andBlog Archive IA Blog

  15. Improving Type Ia Supernova Standard Candle Cosmology Measurements Using Observations of Early-Type Host Galaxies

    E-Print Network [OSTI]

    Meyers, Joshua Evan

    2012-01-01

    Host Galaxies of Type Ia Supernovae Introduction SN Ia Hosts109 C HAPTER 1 Cosmology, Type Ia Supernovae and HostGalaxies Observations of supernovae have played a role in

  16. Three-dimensional numerical simulations of Rayleigh-Taylor unstable flames in type Ia supernovae

    E-Print Network [OSTI]

    Zingale, M.; Woosley, S.E.; Rendleman, C.A.; Day, M.S.; Bell, J.B.

    2005-01-01

    Unstable Flames in Type Ia Supernovae M. Zingale 1 , S. E.Subject headings: supernovae: general — white dwarfs —ame in Type Ia supernovae (SNe Ia) is well recognized (M¨

  17. Technical Report: Impacts of Land Management and Climate on Agroecosystem Greenhouse Gas Exchange in the Upper Midwest United States

    SciTech Connect (OSTI)

    Timothy J. Griffis; John M. Baker

    2007-07-01

    Our research is designed to improve the scientific understanding of how carbon is cycled between the land and atmosphere within a heavily managed landscape that is characteristic of the Upper Midwest. The Objectives are: 1) Quantify the seasonal and interannual variation of net ecosystem CO2 exchange of agricultural ecosystems in the Upper Midwest grown under different management strategies; 2) Partition net ecosystem CO2 exchange into photosynthesis and ecosystem respiration by combining micrometeorological and stable isotope techniques; 3) Examine the seasonal variation in canopy-scale photosynthetic discrimination and the isotope ratios of ecosystem respiration and photosynthesis.

  18. The distant type Ia supernova rate

    SciTech Connect (OSTI)

    Pain, R.; Fabbro, S.; Sullivan, M.; Ellis, R.S.; Aldering, G.; Astier, P.; Deustua, S.E.; Fruchter, A.S.; Goldhaber, G.; Goobar, A.; Groom, D.E.; Hardin, D.; Hook, I.M.; Howell, D.A.; Irwin, M.J.; Kim, A.G.; Kim, M.Y.; Knop, R.A.; Lee, J.C.; Perlmutter, S.; Ruiz-Lapuente, P.; Schahmaneche, K.; Schaefer, B.; Walton, N.A.

    2002-05-20

    We present a measurement of the rate of distant Type Ia supernovae derived using 4 large subsets of data from the Supernova Cosmology Project. Within this fiducial sample,which surveyed about 12 square degrees, thirty-eight supernovae were detected at redshifts 0.25--0.85. In a spatially flat cosmological model consistent with the results obtained by the Supernova Cosmology Project, we derive a rest-frame Type Ia supernova rate at a mean red shift z {approx_equal} 0.55 of 1.53 {sub -0.25}{sub -0.31}{sup 0.28}{sup 0.32} x 10{sup -4} h{sup 3} Mpc{sup -3} yr{sup -1} or 0.58{sub -0.09}{sub -0.09}{sup +0.10}{sup +0.10} h{sup 2} SNu(1 SNu = 1 supernova per century per 10{sup 10} L{sub B}sun), where the first uncertainty is statistical and the second includes systematic effects. The dependence of the rate on the assumed cosmological parameters is studied and the redshift dependence of the rate per unit comoving volume is contrasted with local estimates in the context of possible cosmic star formation histories and progenitor models.

  19. Dark matter ignition of type Ia supernovae

    E-Print Network [OSTI]

    Bramante, Joseph

    2015-01-01

    Recent studies of low redshift type Ia supernovae (SNIa) indicate that half explode from less than Chandrasekhar mass white dwarfs, implying ignition must proceed from something besides the canonical criticality of Chandrasekhar mass SNIa progenitors. We show that $0.1-10$ PeV mass asymmetric dark matter, with imminently detectable nucleon scattering interactions, can accumulate to the point of self-gravitation in a white dwarf and collapse, shedding gravitational potential energy by scattering off nuclei, thereby heating the white dwarf and igniting the flame front that precedes SNIa. We combine data on SNIa masses with data on the ages of SNIa-adjacent stars. This combination reveals a $ 3 \\sigma$ inverse correlation between SNIa masses and ignition ages, which could result from increased capture of dark matter in 1.4 versus 1.1 solar mass white dwarfs. Future studies of SNIa in galactic centers will provide additional tests of dark-matter-induced type Ia ignition. Remarkably, both bosonic and fermionic SNI...

  20. Random Walker Ranking for NCAA Division I-A Football

    E-Print Network [OSTI]

    Porter, Mason A.

    Random Walker Ranking for NCAA Division I-A Football Thomas Callaghan, Peter J. Mucha, and Mason A the top two NCAA Division I-A college football teams in a National Championship game at the end of each in accurately ranking or even agreeing on a ranking methodology for college football lies in two factors

  1. Search for surviving companions in type Ia supernova remnants

    SciTech Connect (OSTI)

    Pan, Kuo-Chuan [Physik Department, Universität Basel, Klingelbergstrasse 82, CH-4056 Basel (Switzerland); Ricker, Paul M. [Department of Astronomy, University of Illinois at Urbana-Champaign, 1002 West Green Street, Urbana, IL 61801 (United States); Taam, Ronald E., E-mail: kuo-chuan.pan@unibas.ch, E-mail: pmricker@illinois.edu, E-mail: r-taam@northwestern.edu, E-mail: taam@asiaa.sinica.edu.tw [Department of Physics and Astronomy, Northwestern University, 2145 Sheridan Road, Evanston, IL 60208 (United States)

    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.

  2. THE ULTRAVIOLET BRIGHTEST TYPE Ia SUPERNOVA 2011de

    SciTech Connect (OSTI)

    Brown, Peter J., E-mail: pbrown@physics.tamu.edu [George P. and Cynthia Woods Mitchell Institute for Fundamental Physics and Astronomy, Texas A and M University, Department of Physics and Astronomy, 4242 TAMU, College Station, TX 77843 (United States)

    2014-11-20

    We present and discuss the ultraviolet (UV)/optical photometric light curves and absolute magnitudes of the Type Ia supernova (SN Ia) 2011de from the Swift Ultraviolet/Optical Telescope. We find it to be the UV brightest SN Ia yet observed—more than a factor of 10 brighter than normal SNe Ia in the mid-ultraviolet. We find that the UV/optical brightness and broad light curve evolution can be modeled with additional flux from the shock of the ejecta hitting a relatively large red giant companion separated by 6 × 10{sup 13} cm. However, the post-maximum behavior of other UV-bright SNe Ia can also be modeled in a similar manner, including objects with UV spectroscopy or pre-maximum photometry which is inconsistent with this model. This suggests that similar UV luminosities can be intrinsic or caused by other forms of shock interaction. The high velocities reported for SN 2011de make it distinct from the UV-bright ''super-Chandrasekhar'' SNe Ia and the NUV-blue group of normal SNe Ia. SN 2011de is an extreme example of the UV variations in SNe Ia.

  3. UNU-IAS Policy Report Biofuels in Africa

    E-Print Network [OSTI]

    UNU-IAS Policy Report Biofuels in Africa Impacts on Ecosystem Services, Biodiversity and Human Well-being #12;#12;UNU-IAS Policy Report Biofuels in Africa Impacts on Ecosystem Services, Biodiversity and Human Research (CSIR) South Africa The views expressed in this publication are those of the authors and do

  4. Diversity of Type Ia Supernovae Imprinted in Chemical Abundances

    E-Print Network [OSTI]

    Tsujimoto, Takuji

    2012-01-01

    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 a SN Ia-like elemental feature including a very low [Mg/Fe] (~-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 gives 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 nice...

  5. A SEARCH FOR NEW CANDIDATE SUPER-CHANDRASEKHAR-MASS TYPE Ia SUPERNOVAE...

    Office of Scientific and Technical Information (OSTI)

    TYPE Ia SUPERNOVAE IN THE NEARBY SUPERNOVA FACTORY DATA SET We present optical photometry and spectroscopy of five Type Ia supernovae discovered by the Nearby Supernova...

  6. Direct numerical simulations of type Ia supernovae flames I: The landau-darrieus instability

    E-Print Network [OSTI]

    Bell, J.B.; Day, M.S.; Rendleman, C.A.; Woosley, S.E.; Zingale, M.

    2003-01-01

    Simulations of Type Ia Supernovae Flames I: The Landau-Subject headings: supernovae: general — white dwarfs —could occur in Type Ia supernovae (Niemeyer & Woosley 1997),

  7. 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.

  8. Southwest Regional Partnership on Carbon Sequestration

    SciTech Connect (OSTI)

    Brian McPherson

    2006-04-01

    The Southwest Partnership on Carbon Sequestration completed several more tasks during the period of April 1, 2005-September 30, 2005. The main objective of the Southwest Partnership project is to evaluate and demonstrate the means for achieving an 18% reduction in carbon intensity by 2012. While Phase 2 planning is well under way, the content of this report focuses exclusively on Phase 1 objectives completed during this reporting period. Progress during this period was focused in the three areas: geological carbon storage capacity in New Mexico, terrestrial sequestration capacity for the project area, and the Integrated Assessment Model efforts. The geologic storage capacity of New Mexico was analyzed and Blanco Mesaverde (which extends into Colorado) and Basin Dakota Pools were chosen as top two choices for the further analysis for CO{sub 2} sequestration in the system dynamics model preliminary analysis. Terrestrial sequestration capacity analysis showed that the four states analyzed thus far (Arizona, Colorado, New Mexico and Utah) have relatively limited potential to sequester carbon in terrestrial systems, mainly due to the aridity of these areas, but the large land area offered could make up for the limited capacity per hectare. Best opportunities were thought to be in eastern Colorado/New Mexico. The Integrated Assessment team expanded the initial test case model to include all New Mexico sinks and sources in a new, revised prototype model in 2005. The allocation mechanism, or ''String of Pearls'' concept, utilizes potential pipeline routes as the links between all combinations of the source to various sinks. This technique lays the groundwork for future, additional ''String of Pearls'' analyses throughout the SW Partnership and other regions as well.

  9. Constraints on Carbon Monoxide Emissions Based on Tall Tower Measurements in the U.S. Upper Midwest

    E-Print Network [OSTI]

    Minnesota, University of

    Constraints on Carbon Monoxide Emissions Based on Tall Tower Measurements in the U.S. Upper Midwest-up emission estimates in response to top-down constraints. 1. INTRODUCTION Carbon monoxide (CO) is a precursor is emitted during the combustion of biomass and fossil fuel and produced photochemically from the oxidation

  10. Impacts of a nuclear war in South Asia on soybean and maize production in the Midwest United States

    E-Print Network [OSTI]

    Robock, Alan

    Impacts of a nuclear war in South Asia on soybean and maize production in the Midwest United States and soybeans to cooler, drier, and darker conditions from war-related smoke. We combined observed climate had an important effect. 1 Introduction In the event of nuclear war, targets in cities and industrial

  11. Fuel-Cycle Fossil Energy Use and Greenhouse Gas Emissions of Fuel Ethanol Produced from U.S. Midwest Corn

    E-Print Network [OSTI]

    Patzek, Tadeusz W.

    #12;Fuel-Cycle Fossil Energy Use and Greenhouse Gas Emissions of Fuel Ethanol Produced from U the ANL Greenhouse gas, Regulated Emissions and Energy in Transportation (GREET) full-fuel-cycle analysis on a mass emission per travel mile basis, the corn-to-ethanol fuel cycle for Midwest-produced ethanol

  12. Type Ia Supernovae: Progenitors and Evolution with Redshift

    E-Print Network [OSTI]

    Ken'ichi Nomoto; Hideyuki Umeda; Chiaki Kobayashi; Izumi Hachisu; Mariko Kato; Takuji Tsujimoto

    2000-03-09

    Relatively uniform light curves and spectral evolution of Type Ia supernovae (SNe Ia) have led to the use of SNe Ia as a ``standard candle'' to determine cosmological parameters. Whether a statistically significant value of the cosmological constant can be obtained depends on whether the peak luminosities of SNe Ia are sufficiently free from the effects of cosmic and galactic evolutions. Here we first review the single degenerate scenario for the Chandrasekhar mass white dwarf (WD) models of SNe Ia. We identify the progenitor's evolution and population with two channels: (1) the WD+RG (red-giant) and (2) the WD+MS (near main-sequence He-rich star) channels. In these channels, the strong wind from accreting WDs plays a key role, which yields important age and metallicity effects on the evolution. We then address the questions whether the nature of SNe Ia depends systematically on environmental properties such as metallicity and age of the progenitor system and whether significant evolutionary effects exist. We suggest that the variation of the carbon mass fraction $X$(C) in the C+O WD (or the variation of the initial WD mass) causes the diversity of the brightness of SNe Ia. This model can explain the observed dependences of SNe Ia brightness on the galaxy types and the distance from the galactic center. Finally, applying the metallicity effect on the evolution of SN Ia progenitors, we make a prediction of the cosmic supernova rate history as a composite of the supernova rates in different types of galaxies.

  13. Type Ia Supernova Progenitors, Environmental Effects, and Cosmic Supernova Rates

    E-Print Network [OSTI]

    Ken'ichi Nomoto; Hideyuki Umeda; Izumi Hachisu; Mariko Kato; Chiaki Kobayashi; Takuji Tsujimoto

    1999-07-27

    Relatively uniform light curves and spectral evolution of Type Ia supernovae (SNe Ia) have led to the use of SNe Ia as a ``standard candle'' to determine cosmological parameters, such as the Hubble constant, the density parameter, and the cosmological constant. Whether a statistically significant value of the cosmological constant can be obtained depends on whether the peak luminosities of SNe Ia are sufficiently free from the effects of cosmic and galactic evolutions. Here we first review the single degenerate scenario for the Chandrasekhar mass white dwarf (WD) models of SNe Ia. We identify the progenitor's evolution and population with two channels: (1) the WD+RG (red-giant) and (2) the WD+MS (near main-sequence He-rich star) channels. In these channels, the strong wind from accreting white dwarfs plays a key role, which yields important age and metallicity effects on the evolution. We then address the questions whether the nature of SNe Ia depends systematically on environmental properties such as metallicity and age of the progenitor system and whether significant evolutionary effects exist. We suggest that the variation of the carbon mass fraction $X$(C) in the C+O WD (or the variation of the initial WD mass) causes the diversity of the brightness of SNe Ia. This model can explain the observed dependence of SNe Ia brighness on the galaxy types. Finally, applying the metallicity effect on the evolution of SN Ia progenitors, we make a prediction of the cosmic supernova rate history as a composite of the supernova rates in different types of galaxies.

  14. Direct-Current Resistivity Survey At Kilauea Southwest Rift And...

    Open Energy Info (EERE)

    data acquired on the southwest rift delineated two distinct basement resistivity structures northwest of the rift zone: a high-resistivity basement at approximately 60 m a.s.l,...

  15. Direct-Current Resistivity At Kilauea Southwest Rift And South...

    Open Energy Info (EERE)

    data acquired on the southwest rift delineated two distinct basement resistivity structures northwest of the rift zone: a high-resistivity basement at approximately 60 m a.s.l,...

  16. Salt Tolerance of Landscape Plants Common to the Southwest 

    E-Print Network [OSTI]

    Miyamoto, S.

    2008-01-01

    With sharply increasing costs of providing potable water, many communities in the Southwest are attempting to utilize non-potable saline water for irrigating large landscapes. This publication provides the information related to salt effects...

  17. Soil Hydraulic Characteristics of a Small Southwest Oregon Watershed Following

    E-Print Network [OSTI]

    --------------------------------------------- Soil Hydraulic Characteristics of a Small Southwest by a high-intensity burn over areas of steep topography. The areal distribution of soil hydraulic of infiltration capacity, saturated hydraulic conductivity, and soil moisture characteristics. Also, measures

  18. Southwest ACSA_Preceedings _182Section_6.2

    E-Print Network [OSTI]

    Ras, Zbigniew W.

    of restaurants?), name 1. SIdeal plan of the city of Sforzinda, Filarete, 1464. Revista de Urbanismo, http://revista urbanismo.uchile.cl/n5/munizagatotal. html, Accessed 13 August 2009. #12;Southwest ACSA_Preceedings _184

  19. DOE Designates Southwest Area and Mid-Atlantic Area National...

    Energy Savers [EERE]

    Corridors DOE Designates Southwest Area and Mid-Atlantic Area National Interest Electric Transmission Corridors October 2, 2007 - 2:50pm Addthis WASHINGTON, DC - U.S. Department...

  20. Southwest Region Experiment Station - Final Technical Report

    SciTech Connect (OSTI)

    Rosenthal, A

    2011-08-19

    Southwest Technology Development Institute (SWTDI), an independent, university-based research institute, has been the operator of the Southwest Region Photovoltaic Experiment Station (SWRES) for almost 30 years. The overarching mission of SWTDI is to position PV systems and solar technologies to become cost-effective, major sources of energy for the United States. Embedded in SWTDI's general mission has been the more-focused mission of the SWRES: to provide value added technical support to the DOE Solar Energy Technologies Program (SETP) to effectively and efficiently meet the R&D needs and targets specified in the SETP Multi-Year Technical Plan. : The DOE/SETP goals of growing U.S. PV manufacturing into giga-watt capacities and seeing tera-watt-hours of solar energy production in the U.S. require an infrastructure that is under development. The staff of the SWRES has supported DOE/SETP through a coherent, integrated program to address infrastructural needs inhibiting wide-scale PV deployment in three major technical categories: specialized engineering services, workforce development, and deployment facilitation. The SWRES contract underwent three major revisions during its five year period-of- performance, but all tasks and deliverables fell within the following task areas: Task 1: PV Systems Assistance Center 1. Develop a Comprehensive multi-year plan 2. Provide technical workforce development materials and workshops for PV stakeholder groups including university, professional installers, inspectors, state energy offices, Federal agencies 3. Serve on the NABCEP exam committee 4. Provide on-demand technical PV system design reviews for U.S. PV stakeholders 5. Provide PV system field testing and instrumentation, technical outreach (including extensive support for the DOE Market Transformation program) Task 2: Design-for-Manufacture PV Systems 1. Develop and install 18 kW parking carport (cost share) and PV-thermal carport (Albuquerque) deriving and publishing lessons learned Task 3: PV Codes and Standards 1. Serve as the national lead for development and preparation of all proposals (related to PV) to the National Electrical Code 2. Participate in the Standards Technical Panels for modules (UL1703) and inverters (UL1741) Task 4: Assess Inverter Long Term Reliability 1. Install and monitor identical inverters at SWRES and SERES 2. Operate and monitor all inverters for 5 years, characterizing all failures and performance trends Task 5: Test and Evaluation Support for Solar America Initiative 1. Provide test and evaluation services to the National Laboratories for stage gate and progress measurements of SAI TPP winners

  1. From Convection to Explosion: End-to-End Simulation of Type Ia Supernovae

    E-Print Network [OSTI]

    Bell, John B.

    Ia supernova is the thermonuclear runaway and subsequent explosion of a white dwarf that is accreting

  2. Practices and Processes of Leading High Performance Home Builders in the Upper Midwest

    SciTech Connect (OSTI)

    Von Thoma, Ed; Ojzcyk, Cindy

    2012-12-01

    The NorthernSTAR Building America Partnership team proposed this study to gain insight into the business, sales, and construction processes of successful high performance builders. The knowledge gained by understanding the high performance strategies used by individual builders, as well as the process each followed to move from traditional builder to high performance builder, will be beneficial in proposing more in-depth research to yield specific action items to assist the industry at large transform to high performance new home construction. This investigation identified the best practices of three successful high performance builders in the upper Midwest. In-depth field analysis of the performance levels of their homes, their business models, and their strategies for market acceptance were explored.

  3. Sweetspot: Near-infrared observations of 13 type Ia supernovae...

    Office of Scientific and Technical Information (OSTI)

    of 13 type Ia supernovae from a new NOAO survey probing the nearby smooth Hubble flow Citation Details In-Document Search Title: Sweetspot: Near-infrared observations of 13...

  4. Single-Degenerate Type Ia Supernovae Are Preferentially Overluminous

    E-Print Network [OSTI]

    Fisher, Robert

    2015-01-01

    Recent observational and theoretical progress has favored merging and helium-accreting sub-Chandrasekhar mass white dwarfs in the double-degenerate and the double-detonation channels, respectively, as the most promising progenitors of normal Type Ia supernovae (SNe Ia). Thus the fate of rapidly-accreting Chandrasekhar mass white dwarfs in the single-degenerate channel remains more mysterious then ever. In this paper, we clarify the nature of ignition in Chandrasekhar-mass single-degenerate SNe Ia by analytically deriving the existence of a characteristic length scale which establishes a transition from central ignitions to buoyancy-driven ignitions. Using this criterion, combined with data from three-dimensional simulations of convection and ignition, we demonstrate that the overwhelming majority of ignition events within Chandrasekhar-mass white dwarfs in the single-degenerate channel are buoyancy-driven, and consequently lack a vigorous deflagration phase. We thus infer that single-degenerate SNe Ia are gen...

  5. The Photometric Properties of Nearby Type Ia Supernovae

    E-Print Network [OSTI]

    Ganeshalingam, Mohan

    2012-01-01

    The Rise-Time Distribution of Nearby Type Ia Supernovae 3.1Highlight: The Physics of Supernovae, ed. W. Hillebrandt &1.1 Supernovae . . . . . . . . . . . . . . 1.1.1

  6. Type Ia Supernova Scenarios and the Hubble Sequence

    E-Print Network [OSTI]

    P. Ruiz-Lapuente; A. Burkert; R. Canal

    1995-05-19

    The dependence of the Type Ia supernova (SN Ia) rate on galaxy type is examined for three currently proposed scenarios: merging of a Chandrasekhar--mass CO white dwarf (WD) with a CO WD companion, explosion of a sub--Chandrasekhar mass CO WD induced by accretion of material from a He star companion, and explosion of a sub--Chandrasekhar CO WD in a symbiotic system. The variation of the SNe Ia rate and explosion characteristics with time is derived, and its correlation with parent population age and galaxy redshift is discussed. Among current scenarios, CO + He star systems should be absent from E galaxies. Explosion of CO WDs in symbiotic systems could account for the SNe Ia rate in these galaxies. The same might be true for the CO + CO WD scenario, depending on the value of the common envelope parameter. A testable prediction of the sub--Chandrasekhar WD model is that the average brightness and kinetic energy of the SN Ia events should increase with redshift for a given Hubble type. Also for this scenario, going along the Hubble sequence from E to Sc galaxies SNe Ia events should be brighter on average and should show larger mean velocities of the ejecta. The observational correlations strongly suggest that the characteristics of the SNe Ia explosion are linked to parent population age. The scenario in which WDs with masses below the Chandrasekhar mass explode appears the most promising one to explain the observed variation of the SN Ia rate with galaxy type together with the luminosity--expansion velocity trend.

  7. Dark Matter Admixed Type Ia Supernovae

    E-Print Network [OSTI]

    Leung, S -C; Lin, L -M

    2015-01-01

    We perform two-dimensional hydrodynamic simulations for the thermonuclear explosion of Chandrasekhar-mass white dwarfs with dark matter (DM) cores in Newtonian gravity. We include a 19-isotope nuclear reaction network and make use of the pure turbulent deflagration model as the explosion mechanism in our simulations. Our numerical results show that the general properties of the explosion depend quite sensitively on the mass of the DM core M$_{{\\rm DM}}$: a larger M$_{{\\rm DM}}$ generally leads to a weaker explosion and a lower mass of synthesized iron-peaked elements. In particular, the total mass of $^{56}$Ni produced can drop from about 0.3 to 0.03 $M_{\\odot}$ as M$_{{\\rm DM}}$ increases from 0.01 to 0.03 $M_{\\odot}$. We have also constructed the bolometric light curves obtained from our simulations and found that our results match well with the observational data of sub-luminous Type-Ia supernovae.

  8. The Fate of Heavy Metals in Highway Stormwater Runoff: The Characterization of a Bioretention Basin in the Midwest

    E-Print Network [OSTI]

    Lacy, Sarah

    2009-01-01

    committee members, Dr. Dennis Lane, Dr. Bryan Young and especially her advisor, Dr. Edward Peltier, for their support and guidance through the development of this project. This work would not have been completed without them graciously offering..., and soils found in the Midwest typically have a higher clay and lower sand content than coastal soils, which slows drainage and causes longer periods of standing water (Peltier et al., 2008). As studies have shown, bioretention basins have...

  9. Simulations of Turbulent Thermonuclear Burning in Type Ia Supernovae

    E-Print Network [OSTI]

    W. Hillebrandt; M. Reinecke; W. Schmidt; F. K. Roepke; C. Travaglio; J. C. Niemeyer

    2004-05-11

    Type Ia supernovae have recently received considerable attention because it appears that they can be used as "standard candles" to measure cosmic distances out to billions of light years away from us. Observations of type Ia supernovae seem to indicate that we are living in a universe that started to accelerate its expansion when it was about half its present age. These conclusions rest primarily on phenomenological models which, however, lack proper theoretical understanding, mainly because the explosion process, initiated by thermonuclear fusion of carbon and oxygen into heavier elements, is difficult to simulate even on supercomputers. Here, we investigate a new way of modeling turbulent thermonuclear deflagration fronts in white dwarfs undergoing a type Ia supernova explosion. Our approach is based on a level set method which treats the front as a mathematical discontinuity and allows for full coupling between the front geometry and the flow field. New results of the method applied to the problem of type Ia supernovae are obtained. It is shown that in 2-D with high spatial resolution and a physically motivated subgrid scale model for the nuclear flames numerically "converged" results can be obtained, but for most initial conditions the stars do not explode. In contrast, simulations in 3-D, do give the desired explosions and many of their properties, such as the explosion energies, lightcurves and nucleosynthesis products, are in very good agreement with observed type Ia supernovae.

  10. Oceanic eddy formation and propagation southwest of Taiwan Feng Nan,1,2

    E-Print Network [OSTI]

    Maine, University of

    Oceanic eddy formation and propagation southwest of Taiwan Feng Nan,1,2 Huijie Xue,2 Peng Xiu,2 Fei October 2011; published 31 December 2011. [1] Oceanic eddies are active and energetic southwest of Taiwan, the Kuroshio Current Loop (KCL) appears southwest of Taiwan more frequently than in other seasons, and ACEs

  11. Evolution of vertical faults at an extensional plate boundary, southwest Iceland

    E-Print Network [OSTI]

    Kattenhorn, Simon

    Evolution of vertical faults at an extensional plate boundary, southwest Iceland James V. Grant1 Abstract Vertical faults having both opening and vertical displacements are common in southwest Iceland of both oblique and normal spreading in southwest Iceland. Individual fracture segments are commonly

  12. Strong Ultraviolet Pulse From a Newborn Type Ia Supernova

    E-Print Network [OSTI]

    Cao, Yi; Howell, D Andrew; Gal-Yam, Avishay; Kasliwal, Mansi M; Valenti, Stefano; Johansson, J; Amanullah, R; Goobar, A; Sollerman, J; Taddia, F; Horesh, Assaf; Sagiv, Ilan; Cenko, S Bradley; Nugent, Peter E; Arcavi, Iair; Surace, Jason; Wo?niak, P R; Moody, Daniela I; Rebbapragada, Umaa D; Bue, Brian D; Gehrels, Neil

    2015-01-01

    Type Ia supernovae are destructive explosions of carbon oxygen white dwarfs. Although they are used empirically to measure cosmological distances, the nature of their progenitors remains mysterious, One of the leading progenitor models, called the single degenerate channel, hypothesizes that a white dwarf accretes matter from a companion star and the resulting increase in its central pressure and temperature ignites thermonuclear explosion. Here we report observations of strong but declining ultraviolet emission from a Type Ia supernova within four days of its explosion. This emission is consistent with theoretical expectations of collision between material ejected by the supernova and a companion star, and therefore provides evidence that some Type Ia supernovae arise from the single degenerate channel.

  13. Practices and Processes of Leading High Performance Home Builders in the Upper Midwest

    SciTech Connect (OSTI)

    Von Thoma, E.; Ojczyk, C.

    2012-12-01

    The NorthernSTAR Building America Partnership team proposed this study to gain insight into the business, sales, and construction processes of successful high performance builders. The knowledge gained by understanding the high performance strategies used by individual builders, as well as the process each followed to move from traditional builder to high performance builder, will be beneficial in proposing more in-depth research to yield specific action items to assist the industry at large transform to high performance new home construction. This investigation identified the best practices of three successful high performance builders in the upper Midwest. In-depth field analysis of the performance levels of their homes, their business models, and their strategies for market acceptance were explored. All three builders commonly seek ENERGY STAR certification on their homes and implement strategies that would allow them to meet the requirements for the Building America Builders Challenge program. Their desire for continuous improvement, willingness to seek outside assistance, and ambition to be leaders in their field are common themes. Problem solving to overcome challenges was accepted as part of doing business. It was concluded that crossing the gap from code-based building to high performance based building was a natural evolution for these leading builders.

  14. SPECTROSCOPY OF TYPE Ia SUPERNOVAE BY THE CARNEGIE SUPERNOVA PROJECT

    SciTech Connect (OSTI)

    Folatelli, Gaston [Kavli Institute for the Physics and Mathematics of the Universe (Kavli IPMU, WPI), Todai Institutes for Advanced Study, the University of Tokyo, 277-8583 Kashiwa (Japan); Morrell, Nidia; Phillips, Mark M.; Hsiao, Eric; Campillay, Abdo; Contreras, Carlos; Castellon, Sergio; Roth, Miguel [Las Campanas Observatory, Carnegie Observatories, Casilla 601, La Serena (Chile); Hamuy, Mario; Anderson, Joseph P. [Departamento de Astronomia, Universidad de Chile, Casilla 36-D, Santiago (Chile); Krzeminski, Wojtek [N. Copernicus Astronomical Center, ul. Bartycka 18, 00-716 Warszawa (Poland); Stritzinger, Maximilian [Department of Physics and Astronomy, Aarhus University, Ny Munkegade 120, DK-8000 Aarhus C (Denmark); Burns, Christopher R.; Freedman, Wendy L.; Madore, Barry F.; Murphy, David; Persson, S. E. [Observatories of the Carnegie Institution of Washington, 813 Santa Barbara Street, Pasadena, CA 91101 (United States); Prieto, Jose L. [Department of Astrophysical Sciences, Princeton University, 4 Ivy Ln., Princeton, NJ 08544 (United States); Suntzeff, Nicholas B.; Krisciunas, Kevin, E-mail: gaston.folatelli@ipmu.jp [George P. and Cynthia Woods Mitchell Institute for Fundamental Physics and Astronomy, Department of Physics and Astronomy, Texas A and M University, College Station, TX 77843 (United States); and others

    2013-08-10

    This is the first release of optical spectroscopic data of low-redshift Type Ia supernovae (SNe Ia) by the Carnegie Supernova Project including 604 previously unpublished spectra of 93 SNe Ia. The observations cover a range of phases from 12 days before to over 150 days after the time of B-band maximum light. With the addition of 228 near-maximum spectra from the literature, we study the diversity among SNe Ia in a quantitative manner. For that purpose, spectroscopic parameters are employed such as expansion velocities from spectral line blueshifts and pseudo-equivalent widths (pW). The values of those parameters at maximum light are obtained for 78 objects, thus providing a characterization of SNe Ia that may help to improve our understanding of the properties of the exploding systems and the thermonuclear flame propagation. Two objects, namely, SNe 2005M and 2006is, stand out from the sample by showing peculiar Si II and S II velocities but otherwise standard velocities for the rest of the ions. We further study the correlations between spectroscopic and photometric parameters such as light-curve decline rate and color. In agreement with previous studies, we find that the pW of Si II absorption features are very good indicators of light-curve decline rate. Furthermore, we demonstrate that parameters such as pW2 (Si II 4130) and pW6 (Si II 5972) provide precise calibrations of the peak B-band luminosity with dispersions of Almost-Equal-To 0.15 mag. In the search for a secondary parameter in the calibration of peak luminosity for SNe Ia, we find a Almost-Equal-To 2{sigma}-3{sigma} correlation between B-band Hubble residuals and the velocity at maximum light of S II and Si II lines.

  15. Type Ia supernovae from merging white dwarfs. I. Prompt detonations

    SciTech Connect (OSTI)

    Moll, R.; Woosley, S. E. [Department of Astronomy and Astrophysics, University of California, Santa Cruz, CA 95064 (United States); Raskin, C.; Kasen, D. [Nuclear Science Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720 (United States)

    2014-04-20

    Merging white dwarfs are a possible progenitor of Type Ia supernovae (SNe Ia). Numerical models suggest that a detonation might be initiated before the stars have coalesced to form a single compact object. Here we study such prompt detonations by means of numerical simulations, modeling the disruption and nucleosynthesis of the stars until the ejecta reach the coasting phase, and generating synthetic light curves and spectra. Three models are considered with primary masses 0.96 M {sub ?}, 1.06 M {sub ?}, and 1.20 M {sub ?}. Of these, the 0.96 M {sub ?} dwarf merging with a 0.81 M {sub ?} companion, with an {sup 56}Ni yield of 0.58 M {sub ?}, is the most promising candidate for reproducing common SNe Ia. The more massive mergers produce unusually luminous SNe Ia with peak luminosities approaching those attributed to 'super-Chandrasekhar' mass SNe Ia. While the synthetic light curves and spectra of some of the models resemble observed SNe Ia, the significant asymmetry of the ejecta leads to large orientation effects. The peak bolometric luminosity varies by more than a factor of two with the viewing angle, and the velocities of the spectral absorption features are lower when observed from angles where the light curve is brightest. The largest orientation effects are seen in the ultraviolet, where the flux varies by more than an order of magnitude. The set of three models roughly obeys a width-luminosity relation, with the brighter light curves declining more slowly in the B band. Spectral features due to unburned carbon from the secondary star are also seen in some cases.

  16. Retail Demand Response in Southwest Power Pool

    SciTech Connect (OSTI)

    Bharvirkar, Ranjit; Heffner, Grayson; Goldman, Charles

    2009-01-30

    In 2007, the Southwest Power Pool (SPP) formed the Customer Response Task Force (CRTF) to identify barriers to deploying demand response (DR) resources in wholesale markets and develop policies to overcome these barriers. One of the initiatives of this Task Force was to develop more detailed information on existing retail DR programs and dynamic pricing tariffs, program rules, and utility operating practices. This report describes the results of a comprehensive survey conducted by LBNL in support of the Customer Response Task Force and discusses policy implications for integrating legacy retail DR programs and dynamic pricing tariffs into wholesale markets in the SPP region. LBNL conducted a detailed survey of existing DR programs and dynamic pricing tariffs administered by SPP's member utilities. Survey respondents were asked to provide information on advance notice requirements to customers, operational triggers used to call events (e.g. system emergencies, market conditions, local emergencies), use of these DR resources to meet planning reserves requirements, DR resource availability (e.g. seasonal, annual), participant incentive structures, and monitoring and verification (M&V) protocols. Nearly all of the 30 load-serving entities in SPP responded to the survey. Of this group, fourteen SPP member utilities administer 36 DR programs, five dynamic pricing tariffs, and six voluntary customer response initiatives. These existing DR programs and dynamic pricing tariffs have a peak demand reduction potential of 1,552 MW. Other major findings of this study are: o About 81percent of available DR is from interruptible rate tariffs offered to large commercial and industrial customers, while direct load control (DLC) programs account for ~;;14percent. o Arkansas accounts for ~;;50percent of the DR resources in the SPP footprint; these DR resources are primarily managed by cooperatives. o Publicly-owned cooperatives accounted for 54percent of the existing DR resources among SPP members. For these entities, investment in DR is often driven by the need to reduce summer peak demand that is used to set demand charges for each distribution cooperative. o About 65-70percent of the interruptible/curtailable tariffs and DLC programs are routinely triggered based on market conditions, not just for system emergencies. Approximately, 53percent of the DR resources are available with less than two hours advance notice and 447 MW can be dispatched with less than thirty minutes notice. o Most legacy DR programs offered a reservation payment ($/kW) for participation; incentive payment levels ranged from $0.40 to $8.30/kW-month for interruptible rate tariffs and $0.30 to $4.60/kW-month for DLC programs. A few interruptible programs offered incentive payments which were explicitly linkedto actual load reductions during events; payments ranged from 2 to 40 cents/kWh for load curtailed.

  17. Southwest Climate Outlook, March 2012 3 | Feature Article

    E-Print Network [OSTI]

    Fay, Noah

    Southwest Climate Outlook, March 2012 3 | Feature Article http://climas half of Arizona, New Mexico, Texas, and Oklahoma com- bined. When all was said and done, damages in the highest 1 percent blanketed almost all of Texas, western Oklahoma, and eastern New Mexico and covered

  18. Southwest Research Institute Signal Exploitation and Geolocation Division

    E-Print Network [OSTI]

    Chapman, Clark R.

    :2008 BY LLOYD'S REGISTER QUALITY ASSURANCE APRIL 1, 2012 CERTIFICATE NUMBER: UQA 0111601 ISO 9001:2008 QualitySouthwest Research Institute ® Signal Exploitation and Geolocation Division CERTIFIED TO ISO 9001 to have the division quality management system certified to the stringent quality standards of ISO 9001

  19. Report for the week of August 10, 2009 Southwest Michigan

    E-Print Network [OSTI]

    Isaacs, Rufus

    Report for the week of August 10, 2009 Southwest Michigan Final Grape IPM Evening Meeting of the Season: Weekly Vineyard IPM Scouting Summary ** The final grape IPM evening meeting of the season vines as the recent rains may have encouraged some late- emerging adults to come out. ** A small amount

  20. NEAR-ULTRAVIOLET PROPERTIES OF A LARGE SAMPLE OF TYPE Ia SUPERNOVAE...

    Office of Scientific and Technical Information (OSTI)

    SUPERNOVAE AS OBSERVED WITH THE Swift UVOT We present ultraviolet (UV) and optical photometry of 26 Type Ia supernovae (SNe Ia) observed from 2005 March to 2008 March with the...

  1. Spectral Observations and Analyses of Low-Redshift Type Ia Supernovae

    E-Print Network [OSTI]

    Silverman, Jeffrey Michael

    2011-01-01

    1.3.2 Thermonuclear Supernovae . . . . . . . . 1.4 Why WriteIa are the result of thermonuclear explosions of C/O whiteIa are the result of thermonuclear explosions of C/O white

  2. The Diversity of Variations in the Spectra of Type Ia Supernovae 

    E-Print Network [OSTI]

    Wagers, Andrew James

    2012-10-19

    Type Ia supernovae (SNe Ia) are currently the best probe of the expansion history of the universe. Their usefulness is due chiefly to their uniformity between supernovae (SNe). However, there are some slight variations amongst SNe that have yet...

  3. Feasibility of Measuring the Cosmological Constant [LAMBDA] and Mass Density [Omega] using Type Ia Supernovae

    E-Print Network [OSTI]

    Goobar, A.

    2008-01-01

    at z = 1. uncertainty for supernovae at z = 1. mR Adding theMass Density .Q Using Type Ia Supernovae A. Goobar and S.Density Q Using Type Ia Supernovae Ariel Goobar l and Saul

  4. UV Spectroscopy of Type Ia Supernovae at Low- and High-Redshift

    E-Print Network [OSTI]

    Nugent, Peter

    2005-01-01

    Spectroscopy of Type Ia Supernovae at Low- and High-RedshiftUV properties of Type Ia Supernovae. The low-redshift studyULDA Access Guide No. 6: Supernovae, The Netherlands: ESA

  5. Hubble Residuals of Nearby SN Ia Are Correlated with Host Galaxy...

    Office of Scientific and Technical Information (OSTI)

    Journal Article: Hubble Residuals of Nearby SN Ia Are Correlated with Host Galaxy Masses Citation Details In-Document Search Title: Hubble Residuals of Nearby SN Ia Are Correlated...

  6. Nearby Supernova Factory Observations of SN 2006D: On Sporadic Carbon Signatures in Early Type Ia Supernova Spectra

    E-Print Network [OSTI]

    2006-01-01

    with low volume-?lling factor. Subject headings: supernovae:general — supernovae: individual (SN 2006D)Introduction Type Ia supernovae (SNe Ia) make valuable

  7. Class IA Phosphoinositide 3-Kinase Modulates Basal Lymphocyte Motility in the Lymph Node1

    E-Print Network [OSTI]

    Parker, Ian

    Class IA Phosphoinositide 3-Kinase Modulates Basal Lymphocyte Motility in the Lymph Node1 Melanie P of the class IA PI3K regulatory subunits p85 and p85 also exhibited reduced velocities, with the magnitude show, for the first time, that class IA PI3Ks play an important role in regulating basal lymphocyte

  8. Identification of the companion stars of Type Ia supernovae

    E-Print Network [OSTI]

    R. Canal; J. Mendez; P. Ruiz-Lapuente

    2000-10-10

    The nature of the binary systems giving rise to Type Ia supernovae (SNeIa) remains an unsolved problem. In this {\\it Letter} we calculate, from the statistics of initial conditions (masses and binary separations), the mass, luminosity, and velocity distributions of the possible binary companions (main-sequence star, subgiant, red giant) following the explosion of the white dwarf which gives rise to the SNeIa. Those companions could be detected from either their proper or their radial motions, by means of high-precision astrometric and radial-velocity measurements in young, nearby supernova remnants. Peculiar velocities typically ranging from 100 to 450 km s$^{-1}$ should be expected, which places proper-motion measurements within reach of HST instruments and makes radial-velocity ones feasible with 2.5-4m class telescopes from the ground. Detections would solve the long-standing problem of which kind of binaries do produce SNeIa and clear up the way to accurate physical modeling of the explosions.

  9. Type Ia supernovae from exploding oxygen-neon white dwarfs

    E-Print Network [OSTI]

    Marquardt, Kai S; Ruiter, Ashley J; Seitenzahl, Ivo R; Ohlmann, Sebastian T; Kromer, Markus; Pakmor, Ruediger; Roepke, Friedrich K

    2015-01-01

    The progenitor problem of Type Ia supernovae (SNe Ia) is still unsolved. Most of these events are thought to be explosions of carbon-oxygen (CO) white dwarfs (WDs), but for many of the explosion scenarios, particularly those involving the externally triggered detonation of a sub-Chandrasekhar mass WD (sub-M Ch WD), there is also a possibility of having an oxygen-neon (ONe) WD as progenitor. We simulate detonations of ONe WDs and calculate synthetic observables from these models. The results are compared with detonations in CO WDs of similar mass and observational data of SNe Ia. We perform hydrodynamic explosion simulations of detonations in initially hydrostatic ONe WDs for a range of masses below the Chandrasekhar mass (M Ch), followed by detailed nucleosynthetic postprocessing with a 384-isotope nuclear reaction network. The results are used to calculate synthetic spectra and light curves, which are then compared with observations of SNe Ia. We also perform binary evolution calculations to determine the nu...

  10. Tracked Flame Simulation for Type Ia Yongmin Zhang1

    E-Print Network [OSTI]

    New York at Stoney Brook, State University of

    tracking of the ame front which is critically important to the accurate modeling of turbulent thermonuclear to be thermonu- clear explosions of white dwarfs. Type Ia supernovae are important sources of energy and chemical, and the strength and brightness of the burning are all determined by the speed of thermonuclear burning 12, 13

  11. Weld Surfacing Edited by Dr I.A. Bucklow

    E-Print Network [OSTI]

    Cambridge, University of

    V01.II Weld Surfacing Edited by Dr I.A. Bucklow ConferenceTechnicalDirector Organised by The Welding Institute in associationwith The Surface Engineering Society THE WELDING INSTITUTE #12;L becomesconfigurationally frozen at a temperature of about 1150°Cduring deposition by the manual-metal-arc welding technique

  12. A static universe is consistent with type Ia supernovae observations

    E-Print Network [OSTI]

    David F. Crawford

    2015-04-18

    This paper considers the hypothesis that the universe is static and demonstrates that type Ia supernova observations which appear to provide strong support for time dilation (and thus for an expanding universe) are equally consistent with a static universe. It is shown that a property of the standard calibration method means that regardless of what redshift dependence the measured light curve widths may have the calibrated widths always have little or no redshift dependence. An important consideration is the Phillips relation, a correlation between the peak-luminosity and the width of type Ia supernovae. Using the Phillips relation the analysis of a recent compilation of type Ia supernova observations is re-examined and it is shown that these observations are fully consistent with a static universe. It is also argued that the photometric redshift relation and spectroscopic ages are fully consistent with a static universe. As a separate but related issue it is shown that in the static model the density distribution of type Ia supernovae as a function of redshift agrees with the observations. All the evidence shows that the hypothesis is consistent with a static universe.

  13. The EqIA Publishing Template Impact Assessment Summary

    E-Print Network [OSTI]

    and aims of the policy, function or service. Resource Allocation for the period April 2010 to March 2013 3The EqIA Publishing Template Impact Assessment Summary 1. Name of policy, function or service. Who will benefit mainly from this policy, function or service? This plan provides for the sustainable

  14. Could there be a hole in type Ia supernovae?

    SciTech Connect (OSTI)

    Kasen, Daniel; Nugent, Peter; Thomas, R.C.; Wang, Lifan

    2004-04-23

    In the favored progenitor scenario, Type Ia supernovae (SNe Ia) arise from a white dwarf accreting material from a non-degenerate companion star. Soon after the white dwarf explodes, the ejected supernova material engulfs the companion star; two-dimensional hydrodynamical simulations by Marietta et al. (2001) show that, in the interaction, the companion star carves out a conical hole of opening angle 30-40 degrees in the supernova ejecta. In this paper we use multi-dimensional Monte Carlo radiative transfer calculations to explore the observable consequences of an ejecta-hole asymmetry. We calculate the variation of the spectrum, luminosity, and polarization with viewing angle for the aspherical supernova near maximum light. We find that the supernova looks normal from almost all viewing angles except when one looks almost directly down the hole. In the latter case, one sees into the deeper, hotter layers of ejecta. The supernova is relatively brighter and has a peculiar spectrum characterized by more highly ionized species, weaker absorption features, and lower absorption velocities. The spectrum viewed down the hole is comparable to the class of SN 1991T-like supernovae. We consider how the ejecta-hole asymmetry may explain the current spectropolarimetric observations of SNe Ia, and suggest a few observational signatures of the geometry. Finally, we discuss the variety currently seen in observed SNe Ia and how an ejecta-hole asymmetry may fit in as one of several possible sources of diversity.

  15. XRETRIEVE (request, i.a.) (iris.washington.edu)

    E-Print Network [OSTI]

    Laske, Gabi

    XRETRIEVE (request, i.a.) BDSN MEDNET IRIS DMC (iris.washington.edu) GEOSCOPE BREQ_FAST (request) email to BREQ_FAST@sob.iris.washington.edu interactive non-interactive customized pre-assembled customized pre-assembled www.iris.washington.edu (seismiquery/data sources) www.iris.washington.edu (FARM

  16. Thermonuclear supernova models, and observations of Type Ia supernovae

    E-Print Network [OSTI]

    E. Bravo; C. Badenes; D. Garcia-Senz

    2004-12-07

    In this paper, we review the present state of theoretical models of thermonuclear supernovae, and compare their predicitions with the constraints derived from observations of Type Ia supernovae. The diversity of explosion mechanisms usually found in one-dimensional simulations is a direct consequence of the impossibility to resolve the flame structure under the assumption of spherical symmetry. Spherically symmetric models have been successful in explaining many of the observational features of Type Ia supernovae, but they rely on two kinds of empirical models: one that describes the behaviour of the flame on the scales unresolved by the code, and another that takes account of the evolution of the flame shape. In contrast, three-dimensional simulations are able to compute the flame shape in a self-consistent way, but they still need a model for the propagation of the flame in the scales unresolved by the code. Furthermore, in three dimensions the number of degrees of freedom of the initial configuration of the white dwarf at runaway is much larger than in one dimension. Recent simulations have shown that the sensitivity of the explosion output to the initial conditions can be extremely large. New paradigms of thermonuclear supernovae have emerged from this situation, as the Pulsating Reverse Detonation. The resolution of all these issues must rely on the predictions of observational properties of the models, and their comparison with current Type Ia supernova data, including X-ray spectra of Type Ia supernova remnants.

  17. Cosmic Supernova Rate History and Type Ia Supernova Progenitors

    E-Print Network [OSTI]

    Chiaki Kobayashi; Ken'ichi Nomoto; Takuji Tsujimoto

    2001-02-14

    Adopting a single degenerate scenario for Type Ia supernova progenitors with the metallicity effect, we make a prediction of the cosmic supernova rate history as a composite of the supernova rates in spiral and elliptical galaxies, and compare with the recent observational data up to z ~ 0.55.

  18. Dramatic Demand Reduction In The Desert Southwest

    SciTech Connect (OSTI)

    Boehm, Robert; Hsieh, Sean; Lee, Joon; Baghzouz, Yahia; Cross, Andrew; Chatterjee, Sarah

    2015-07-06

    This report summarizes a project that was funded to the University of Nevada Las Vegas (UNLV), with subcontractors Pulte Homes and NV Energy. The project was motivated by the fact that locations in the Desert Southwest portion of the US demonstrate very high peak electrical demands, typically in the late afternoons in the summer. These high demands often require high priced power to supply the needs, and the large loads can cause grid supply problems. An approach was proposed through this contact that would reduce the peak electrical demands to an anticipated 65% of what code-built houses of the similar size would have. It was proposed to achieve energy reduction through four approaches applied to a development of 185 homes in northwest part of Las Vegas named Villa Trieste. First, the homes would all be highly energy efficient. Secondly, each house would have a PV array installed on it. Third, an advanced demand response technique would be developed to allow the resident to have some control over the energy used. Finally, some type of battery storage would be used in the project. Pulte Homes designed the houses. The company considered initial cost vs. long-term savings and chose options that had relatively short paybacks. HERS (Home Energy Rating Service) ratings for the homes are approximately 43 on this scale. On this scale, code-built homes rate at 100, zero energy homes rate a 0, and Energy Star homes are 85. In addition a 1.764 Wp (peak Watt) rated PV array was used on each house. This was made up of solar shakes that were in visual harmony with the roofing material used. A demand response tool was developed to control the amount of electricity used during times of peak demand. While demand response techniques have been used in the utility industry for some time, this particular approach is designed to allow the customer to decide the degree of participation in the response activity. The temperature change in the residence can be decided by the residents by adjusting settings. In a sense the customer can choose between greater comfort and greater money savings during demand response circumstances. Finally a battery application was to be considered. Initially it was thought that a large battery (probably a sodium-sulfur type) would be installed. However, after the contract was awarded, it was determined that a single, centrally-located battery system would not be appropriate for many reasons, including that with the build out plan there would not be any location to put it. The price had risen substantially since the budget for the project was put together. Also, that type of battery has to be kept hot all the time, but its use was only sought for summer operation. Hence, individual house batteries would be used, and these are discussed at the end of this report. Many aspects of the energy use for climate control in selected houses were monitored before residents moved in. This was done both to understand the magnitude of the energy flows but also to have data that could be compared to the computer simulations. The latter would be used to evaluate various aspects of our plan. It was found that good agreement existed between actual energy use and computed energy use. Hence, various studies were performed via simulations. Performance simulations showed the impact on peak energy usage between a code built house of same size and shape compared to the Villa Trieste homes with and without the PV arrays on the latter. Computations were also used to understand the effect of varying orientations of the houses in this typical housing development, including the effect of PV electrical generation. Energy conservation features of the Villa Trieste homes decreased the energy use during peak times (as well as all others), but the resulting decreased peak occurred at about the same time as the code-built houses. Consideration of the PV generation decreases the grid energy use further during daylight hours, but did not extend long enough many days to decrease the peak. Hence, a demand response approach, as planned, was needed. With p

  19. Low-Metallicity Inhibition of Type Ia Supernovae and Galactic and Cosmic Chemical Evolution

    E-Print Network [OSTI]

    Chiaki Kobayashi; Takuji Tsujimoto; Ken'ich Nomoto; Izumi Hachisu; Mariko Kato

    1998-06-25

    We introduce a metallicity dependence of Type Ia supernova (SN Ia) rate into the Galactic and cosmic chemical evolution models. In our SN Ia progenitor scenario, the accreting white dwarf (WD) blows a strong wind to reach the Chandrasekhar mass limit. If the iron abundance of the progenitors is as low as [Fe/H] 1-2, SNe Ia can be found only in the environments where the timescale of metal enrichment is sufficiently short as in starburst galaxies and ellipticals. The low-metallicity inhibition of SNe Ia can shed new light on the following issues: 1) The limited metallicity range of the SN Ia progenitors would imply that ``evolution effects'' are relatively small for the use of high redshift SNe Ia to determine the cosmological parameters. 2) WDs of halo populations are poor producers of SNe Ia, so that the WD contribution to the halo mass is not constrained from the iron abundance in the halo. 3) The abundance patterns of globular clusters and field stars in the Galactic halo lack of SN Ia signatures in spite of their age difference of several Gyrs, which can be explained by the low-metallicity inhibition of SNe Ia. 4) It could also explain why the SN Ia contamination is not seen in the damped Ly\\alpha systems for over a wide range of redshift.

  20. An Analysis of Department of Defense Instruction 8500.2 'Information Assurance (IA) Implementation.'

    SciTech Connect (OSTI)

    Campbell, Philip LaRoche

    2012-01-01

    The Department of Defense (DoD) provides its standard for information assurance in its Instruction 8500.2, dated February 6, 2003. This Instruction lists 157 'IA Controls' for nine 'baseline IA levels.' Aside from distinguishing IA Controls that call for elevated levels of 'robustness' and grouping the IA Controls into eight 'subject areas' 8500.2 does not examine the nature of this set of controls, determining, for example, which controls do not vary in robustness, how this set of controls compares with other such sets, or even which controls are required for all nine baseline IA levels. This report analyzes (1) the IA Controls, (2) the subject areas, and (3) the Baseline IA levels. For example, this report notes that there are only 109 core IA Controls (which this report refers to as 'ICGs'), that 43 of these core IA Controls apply without variation to all nine baseline IA levels and that an additional 31 apply with variations. This report maps the IA Controls of 8500.2 to the controls in NIST 800-53 and ITGI's CoBIT. The result of this analysis and mapping, as shown in this report, serves as a companion to 8500.2. (An electronic spreadsheet accompanies this report.)

  1. Analytical Expressions For Light-Curves Of Ordinary And Superluminous Supernovae Type Ia

    E-Print Network [OSTI]

    Shlomo Dado; Arnon Dar

    2015-06-25

    Supernovae of type Ia (SNeIa) can be produced by the explosion of slowly-rotating carbon-oxygen white dwarfs whose mass increases beyond a critical value by mass accretion. Collision with circumstellar material during their photospheric and early nebular phase can enhance the bolometric luminosity of otherwise ordinary SNeIa to become superluminous. A few simplifying assumptions lead to a simple analytic master formula, which describes quite well the bolometric light-curves of ordinary SNeIa and supeluminous SNeIa in terms of few initial physical parameters. Other main properties of SNeIa, including the empirical 'brighter-slower' Phillips' relation that was used to standardize ordinary SNeIa as distance indicators and led to the discovery of the accelerating expansion of the universe, are reproduced

  2. Mauna Loa Southwest Rift Geothermal Area | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QAsource History View NewTexas:Montezuma,InformationIllinois:Martin,OpenMatthews, NorthMauna Loa Southwest

  3. Kilauea Southwest Rift And South Flank Geothermal Area | Open Energy

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QAsource History View NewTexas: Energy ResourcesOrderInformation Kilauea Southwest Rift And South Flank

  4. The potential impacts of a competitive wholesale market in the midwest: A preliminary examination of centralized dispatch

    SciTech Connect (OSTI)

    Lesieutre, Bernard C.; Bartholomew, Emily; Eto, Joseph H.; Hale, Douglas; Luong, Thanh

    2004-07-01

    In March 2005, the Midwest Independent System Operator (MISO) will begin operating the first-ever wholesale market for electricity in the central and upper Midwestern portion of the United States. Region-wide, centralized, security-constrained, bid-based dispatch will replace the current system of decentralized dispatch by individual utilities and control areas. This report focuses on how the operation of generators may change under centralized dispatch. We analyze a stylized example of these changes by comparing a base case dispatch based on a ''snapshot'' taken from MISO's state estimator for an actual, historical dispatch (4 p.m., July 7, 2003) to a hypothetical, centralized dispatch that seeks to minimize the total system cost of production, using estimated cost data collected by the EIA. Based on these changes in dispatch, we calculate locational marginal prices, which in turn reveals the location of congestion within MISO's footprint, as well as the distribution of congestion revenues. We also consider two sensitivity scenarios that examine (1) the effect of changes in MISO membership (2003 vs. 2004 membership lists), and (2) different load and electrical data, based on a snapshot from a different date and time (1 p.m., Feb. 18, 2004). Although our analysis offers important insights into how the MISO market could operate when it opens, we do not address the question of the total benefits or costs of creating a wholesale market in the Midwest.

  5. Fuel ethanol produced from U.S. Midwest corn : help or hindrance to the vision of Kyoto?

    SciTech Connect (OSTI)

    Wang, M.; Saricks, C.; Wu, M.; Energy Systems

    1999-07-01

    In this study, we examined the role of corn-feedstock ethanol in reducing greenhouse gas (GHG) emissions, given present and near-future technology and practice for corn farming and ethanol production. We analyzed the full-fuel-cycle GHG effects of corn-based ethanol using updated information on corn operations in the upper Midwest and existing ethanol production technologies. Information was obtained from representatives of the U.S. Department of Agriculture, faculty of midwestern universities with expertise in corn production and animal feed, and acknowledged authorities in the field of ethanol plant engineering, design, and operations. Cases examined included use of E85 (85% ethanol and 15% gasoline by volume) and E10 (10% ethanol and 90% gasoline). Among key findings is that Midwest-produced ethanol outperforms conventional (current) and reformulated (future) gasoline with respect to energy use and GHG emissions (on a mass emission per travel mile basis). The superiority of the energy and GHG results is well outside the range of model noise. An important facet of this work has been conducting sensitivity analyses. These analyses let us rank the factors in the corn-to-ethanol cycle that are most important for limiting GHG generation. These rankings could help ensure that efforts to reduce that generation are targeted more effectively.

  6. Type Ia Supernova Spectral Line Ratios as LuminosityIndicators

    SciTech Connect (OSTI)

    Bongard, Sebastien; Baron, E.; Smadja, G.; Branch, David; Hauschildt, Peter H.

    2005-12-07

    Type Ia supernovae have played a crucial role in thediscovery of the dark energy, via the measurement of their light curvesand the determination of the peak brightness via fitting templates to theobserved lightcurve shape. Two spectroscopic indicators are also known tobe well correlated with peak luminosity. Since the spectroscopicluminosity indicators are obtained directly from observed spectra, theywill have different systematic errors than do measurements usingphotometry. Additionally, these spectroscopic indicators may be usefulfor studies of effects of evolution or age of the SNe~;Ia progenitorpopulation. We present several new variants of such spectroscopicindicators which are easy to automate and which minimize the effects ofnoise. We show that these spectroscopic indicators can be measured byproposed JDEM missions such as snap and JEDI.

  7. Power-law cosmology, SN Ia, and BAO

    SciTech Connect (OSTI)

    Dolgov, Aleksander; Halenka, Vitali; Tkachev, Igor E-mail: vithal@umich.edu

    2014-10-01

    We revise observational constraints on the class of models of modified gravity which at low redshifts lead to a power-law cosmology. To this end we use available public data on Supernova Ia and on baryon acoustic oscillations. We show that the expansion regime a(t) ? t{sup ?} with ? close to 3/2 in a spatially flat universe is a good fit to these data.

  8. Signatures of a companion star in type Ia supernovae

    SciTech Connect (OSTI)

    Maeda, Keiichi [Department of Astronomy, Kyoto University, Kitashirakawa-Oiwake-cho, Sakyo-ku, Kyoto 606-8502 (Japan); Kutsuna, Masamichi; Shigeyama, Toshikazu, E-mail: keiichi.maeda@kusastro.kyoto-u.ac.jp [Research Center for the Early Universe, School of Science, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033 (Japan)

    2014-10-10

    Although type Ia supernovae (SNe Ia) have been used as precise cosmological distance indicators, their progenitor systems remain unresolved. One of the key questions is whether there is a nondegenerate companion star at the time of a thermonuclear explosion of a white dwarf. In this paper, we investigate whether an interaction between the SN ejecta and the companion star may result in observable footprints around the maximum brightness and thereafter, by performing multidimensional radiation transfer simulations based on hydrodynamic simulations of the interaction. We find that such systems result in variations in various observational characteristics due to different viewing directions, and the predicted behaviors (redder and fainter for the companion direction) are the opposite of what were suggested by the previous study. The variations are generally modest and within observed scatters. However, the model predicts trends between some observables different from those observationally derived, so a large sample of SNe Ia with small calibration errors may be used to constrain the existence of such a companion star. The variations in different colors in optical band passes can be mimicked by external extinctions, so such an effect could be a source of scatter in the peak luminosity and derived distance. After the peak, hydrogen-rich materials expelled from the companion will manifest themselves in hydrogen lines, but H? is extremely difficult to identify. Alternatively, we find that P{sub ?} in postmaximum near-infrared spectra can potentially provide a powerful diagnostic.

  9. CARBON DEFLAGRATION IN TYPE Ia SUPERNOVA. I. CENTRALLY IGNITED MODELS

    SciTech Connect (OSTI)

    Ma, H.; Woosley, S. E.; Malone, C. M. [Department of Astronomy and Astrophysics, University of California, Santa Cruz, CA 95064 (United States); Almgren, A.; Bell, J. [Center for Computational Sciences and Engineering, Lawrence Berkeley National Lab, Berkeley, CA 94720 (United States)

    2013-07-01

    A leading model for Type Ia supernovae (SNe Ia) begins with a white dwarf near the Chandrasekhar mass that ignites a degenerate thermonuclear runaway close to its center and explodes. In a series of papers, we shall explore the consequences of ignition at several locations within such dwarfs. Here we assume central ignition, which has been explored before, but is worth revisiting, if only to validate those previous studies and to further elucidate the relevant physics for future work. A perturbed sphere of hot iron ash with a radius of {approx}100 km is initialized at the middle of the star. The subsequent explosion is followed in several simulations using a thickened flame model in which the flame speed is either fixed-within the range expected from turbulent combustion-or based on the local turbulent intensity. Global results, including the explosion energy and bulk nucleosynthesis (e.g., {sup 56}Ni of 0.48-0.56 M{sub Sun }) turn out to be insensitive to this speed. In all completed runs, the energy released by the nuclear burning is adequate to unbind the star, but not enough to give the energy and brightness of typical SNe Ia. As found previously, the chemical stratification observed in typical events is not reproduced. These models produce a large amount of unburned carbon and oxygen in central low velocity regions, which is inconsistent with spectroscopic observations, and the intermediate mass elements and iron group elements are strongly mixed during the explosion.

  10. The 1999 Midwest Symposium on Circuits and Systems, New Mexico State University, Aug. 1999 Random-Process Formulation of Computationally Efficient

    E-Print Network [OSTI]

    Vanderbei, Robert J.

    The 1999 Midwest Symposium on Circuits and Systems, New Mexico State University, Aug. 1999 Random formulation of design con- straints in such an optimization setting and illustrates the concepts through dimensions of an approach developed earlier for the design of FIR digital filters in one dimension [4

  11. THE SECURITY-CONSTRAINED COMMITMENT AND DISPATCH FOR MIDWEST ISO DAY-AHEAD CO-OPTIMIZED ENERGY AND ANCILLARY SERVICE MARKET

    E-Print Network [OSTI]

    Tesfatsion, Leigh

    improve grid reliability. Key words ­ Electricity market, LMP, Security Constrained Unit Commitment (SCUCTHE SECURITY-CONSTRAINED COMMITMENT AND DISPATCH FOR MIDWEST ISO DAY-AHEAD CO-OPTIMIZED ENERGY ­ This paper reports upon the security-constrained commitment and dispatch algorithms and their implementation

  12. Gravitational Wave Emission from the Single-Degenerate Channel of Type Ia Supernovae

    E-Print Network [OSTI]

    David Falta; Robert T. Fisher; Gaurav Khanna

    2011-05-28

    The thermonuclear explosion of a C/O white dwarf as a Type Ia supernova (SN Ia) generates a kinetic energy comparable to that released by a massive star during a SN II event. Current observations and theoretical models have established that SNe Ia are asymmetric, and therefore--like SNe II--potential sources of gravitational wave (GW) radiation. We perform the first detailed calculations of the GW emission for a SN Ia of any type within the single-degenerate channel. The gravitationally-confined detonation (GCD) mechanism predicts a strongly-polarized GW burst in the frequency band around 1 Hz. Third-generation spaceborne GW observatories currently in planning may be able to detect this predicted signal from SNe Ia at distances up to 1 Mpc. If observable, GWs may offer a direct probe into the first few seconds of the SNe Ia detonation.

  13. Teor'ia de Grupos y Mec'anica Qu'antica Luis A. Seco

    E-Print Network [OSTI]

    Seco, Luis A.

    Teor'ia de Grupos y Mec'anica Qu'antica Luis A. Seco Universidad de Toronto. Notas del curso; Teor'ia de Grupos y Mec'anica Cu'antica, L. Seco. U.I.M.P. La Coru~na, 27 Junio -- 1 Julio, 1994. Preliminares Este curso recoge diversos temas que se encuentran a caballo entre la teor'ia de grupos y la mec

  14. Lehigh Southwest Cement Company: Compressed Air System Improvement Saves Energy

    SciTech Connect (OSTI)

    2003-10-01

    In 2001, Lehigh Southwest Cement Company improved the compressed air system at its cement plant in Tehachapi, California. Consequently, the system was able to operate more efficiently with less compressor capacity and at a lower system pressure. The project yielded total annual savings of 895,000 kWh and $199,000. The initial project cost was $417,000, but Southern California Edison provided a $90,000 incentive payment to reduce the cost to $327,000. Simple payback was about 20 months.

  15. Mauna Loa Southwest Rift Geothermal Area | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QAsource History View NewTexas:Montezuma,InformationIllinois:Martin,OpenMatthews, NorthMauna Loa Southwest Rift

  16. Southwest Arkansas E C C | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QA J-E-1 SECTION JEnvironmental Jump to:EA EIS ReportEurope GmbHSoloPage Edit with form History Southwest Arkansas E

  17. A Multi-scale Study of Inorganic Aqueous Solution (IAS) for Advanced Heat Pipe Applications

    E-Print Network [OSTI]

    Amouzegar Ashtiani, Ladan

    2015-01-01

    Surfaces to Wetting by Water," Industrial & Engineeringheterogenous porous media," WATER RESOURCES RESEARCH, vol.Exp. 1 Exp. 2 Exp. 3 Exp. 4 water water IAS#0 working fluid

  18. THE HYBRID CONe WD + He STAR SCENARIO FOR THE PROGENITORS OF TYPE Ia SUPERNOVAE

    SciTech Connect (OSTI)

    Wang, B.; Meng, X.; Liu, D.-D.; Han, Z. [Yunnan Observatories, Chinese Academy of Sciences, Kunming 650011 (China); Liu, Z.-W., E-mail: wangbo@ynao.ac.cn [Argelander-Institut für Astronomie, Auf dem Hügel 71, D-53121, Bonn (Germany)

    2014-10-20

    Hybrid CONe white dwarfs (WDs) have been suggested to be possible progenitors of type Ia supernovae (SNe Ia). In this Letter, we systematically studied the hybrid CONe WD + He star scenario for the progenitors of SNe Ia, in which a hybrid CONe WD increases its mass to the Chandrasekhar mass limit by accreting He-rich material from a non-degenerate He star. We obtained the SN Ia birthrates and delay times for this scenario using to a series of detailed binary population synthesis simulations. The SN Ia birthrates for this scenario are ?0.033-0.539 × 10{sup –3} yr{sup –1}, which roughly accounts for 1%-18% of all SNe Ia. The estimated delay times are ?28 Myr-178 Myr, which makes these the youngest SNe Ia predicted by any progenitor model so far. We suggest that SNe Ia from this scenario may provide an alternative explanation for type Iax SNe. We also presented some properties of the donors at the point when the WDs reach the Chandrasekhar mass. These properties may be a good starting point for investigating the surviving companions of SNe Ia and for constraining the progenitor scenario studied in this work.

  19. Multi-layered Spectral Formation in SNe Ia Around Maximum Light

    E-Print Network [OSTI]

    Bongard, Sebastien

    2008-01-01

    stars: atmospheres — supernovae DISCLAIMER This document wasIntroduction Type Ia supernovæ have been used as “spanning the “normal” supernovæ blue magnitudes. Single Ion

  20. High-Redshift Type Ia Supernova Rates in Galaxy Cluster and Field Environments

    E-Print Network [OSTI]

    Barbary, Kyle Harris

    2011-01-01

    29 Candidates classified as supernovae . . . . . . . .1.1 Type Ia Supernovae as Standard Candles . . . . . . . .4.2.3 Supernovae . . . . . . . . . . . . . . . . 4.2.4

  1. Direct numerical simulations of type Ia supernovae flames II: The rayleigh-taylor instability

    E-Print Network [OSTI]

    Bell, J.B.; Day, M.S.; Rendleman, C.A.; Woosley, S.E.; Zingale, M.

    2004-01-01

    Weaver, T. A. 1994, in Supernovae, Les Houches, Session LIV,Simulations of Type Ia Supernovae Flames II: The Rayleigh-Subject headings: supernovae: general — white dwarfs —

  2. Timescale stretch parameterization of Type Ia supernova B-band light curves

    E-Print Network [OSTI]

    2001-01-01

    the light curve of Type Ia supernovae discovered by theof the high-redshift supernovae. This work was supported inobjects. Subject headings: supernovae: general – cosmology:

  3. The Carnegie Supernova Project: Intrinsic colors of type Ia supernovae

    SciTech Connect (OSTI)

    Burns, Christopher R.; Persson, S. E.; Freedman, Wendy L.; Madore, Barry F. [Observatories of the Carnegie Institution for Science, 813 Santa Barbara Street, Pasadena, CA 91101 (United States); Stritzinger, Maximilian; Contreras, Carlos [Department of Physics and Astronomy, Aarhus University, Ny Munkegade 120, DK-8000 Aarhus C (Denmark); Phillips, M. M.; Hsiao, E. Y.; Boldt, Luis; Campillay, Abdo; Castellón, Sergio; Morrell, Nidia; Salgado, Francisco [Carnegie Institution of Washington, Las Campanas Observatory, Colina El Pino, Casilla 601 (Chile); Folatelli, Gaston [Kavli Institute for the Physics and Mathematics of the Universe, Todai Institutes for Advanced Study, the University of Tokyo, 277-8583 Kashiwa (Japan); Suntzeff, Nicholas B. [George P. and Cynthia Woods Mitchell Institute for Fundamental Physics and Astronomy, Texas A and M University, Department of Physics and Astronomy, College Station, TX 77843 (United States)

    2014-07-01

    We present an updated analysis of the intrinsic colors of Type Ia supernova (SNe Ia) using the latest data release of the Carnegie Supernova Project. We introduce a new light-curve parameter very similar to stretch that is better suited for fast-declining events, and find that these peculiar types can be seen as extensions to the population of 'normal' SNe Ia. With a larger number of objects, an updated fit to the Lira relation is presented along with evidence for a dependence on the late-time slope of the B – V light-curves with stretch and color. Using the full wavelength range from u to H band, we place constraints on the reddening law for the sample as a whole and also for individual events/hosts based solely on the observed colors. The photometric data continue to favor low values of R{sub V} , though with large variations from event to event, indicating an intrinsic distribution. We confirm the findings of other groups that there appears to be a correlation between the derived reddening law, R{sub V} , and the color excess, E(B – V), such that larger E(B – V) tends to favor lower R{sub V} . The intrinsic u-band colors show a relatively large scatter that cannot be explained by variations in R{sub V} or by the Goobar power-law for circumstellar dust, but rather is correlated with spectroscopic features of the supernova and is therefore likely due to metallicity effects.

  4. Geology of the Hilda-Southwest area, Mason County, Texas 

    E-Print Network [OSTI]

    Ammer, Bobby Rex

    1959-01-01

    antts. 'ka the yalloelsh byoen, aiasadvely bedded:: sccndetona bf tha walwe "mailbox & vhds '-'aoeieeybnde&. dn. '~al, to. an'sbgayt ~ Xn -taiwatat4on, and toyowtnyhy cehlob shoes'-:dlstgootly; on', ace'lal yhotogw@yhs. Thy'wanga ia~g'' Iy a' ws..., ~' +. "'. i" a" e'', e', ?, 'w 'i'', ". i"''y, 'ii:"'i'; +':w', "y, i', 4'"'i' '', '65. l; ZCN(KC . 6KKCST' g"'i" g -. 'a. , '?' 'y, "'j 'l a', , ~ . o, , +, I' 'e" ~ e 'i- c' ?, . 'w e BERARNCZQ. ' e s . w 'a ~, q a e +, w a ~ r, ~ ~ e ~ e r + y y, g...

  5. Marginal evidence for cosmic acceleration from Type Ia supernovae

    E-Print Network [OSTI]

    Jeppe Trøst Nielsen; Alberto Guffanti; Subir Sarkar

    2015-06-09

    The "standard" model of cosmology is founded on the basis that the expansion rate of the universe is accelerating at present --- as was inferred originally from the Hubble diagram of Type Ia supernovae. There exists now a much bigger database of supernovae so we can perform rigorous statistical tests to check whether these "standardisable candles" indeed indicate cosmic acceleration. Taking account of the empirical procedure by which corrections are made to their absolute magnitudes to allow for the varying shape of the light curve and extinction by dust, we find, rather surprisingly, that the data are still quite consistent with a constant rate of expansion.

  6. Marginal evidence for cosmic acceleration from Type Ia supernovae

    E-Print Network [OSTI]

    Nielsen, Jeppe Trøst; Sarkar, Subir

    2015-01-01

    The `standard' model of cosmology is founded on the basis that the expansion rate of the universe is accelerating at present --- as was inferred originally from the Hubble diagram of Type Ia supernovae. There exists now a much bigger database of supernovae so we can perform rigorous statistical tests to check whether these `standardisable candles' indeed indicate cosmic acceleration. Taking account of the empirical procedure by which corrections are made to their absolute magnitudes to allow for the varying shape of the light curve and extinction by dust, we find, rather surprisingly, that the data are still quite consistent with a constant rate of expansion.

  7. Grouping normal type Ia supernovae by UV to optical color differences

    SciTech Connect (OSTI)

    Milne, Peter A.; Brown, Peter J.; Roming, Peter W. A.; Bufano, Filomena; Gehrels, Neil

    2013-12-10

    Observations of many Type Ia supernovae (SNe Ia) for multiple epochs per object with the Swift Ultraviolet Optical Telescope instrument have revealed that there exists order to the differences in the UV-optical colors of optically normal supernovae (SNe). We examine UV-optical color curves for 23 SNe Ia, dividing the SNe into four groups, and find that roughly one-third of 'NUV-blue' SNe Ia have bluer UV-optical colors than the larger 'NUV-red' group. Two minor groups are recognized, 'MUV-blue' and 'irregular' SNe Ia. While we conclude that the latter group is a subset of the NUV-red group, containing the SNe with the broadest optical peaks, we conclude that the 'MUV-blue' group is a distinct group. Separating into the groups and accounting for the time evolution of the UV-optical colors lowers the scatter in two NUV-optical colors (e.g., u – v and uvw1 – v) to the level of the scatter in b – v. This finding is promising for extending the cosmological utilization of SNe Ia into the NUV. We generate spectrophotometry of 33 SNe Ia and determine the correct grouping for each. We argue that there is a fundamental spectral difference in the 2900-3500 Å wavelength range, a region suggested to be dominated by absorption from iron-peak elements. The NUV-blue SNe Ia feature less absorption than the NUV-red SNe Ia. We show that all NUV-blue SNe Ia in this sample also show evidence of unburned carbon in optical spectra, whereas only one NUV-red SN Ia features that absorption line. Every NUV-blue event also exhibits a low gradient of the Si II ?6355 absorption feature. Many NUV-red events also exhibit a low gradient, perhaps suggestive that NUV-blue events are a subset of the larger low-velocity gradient group.

  8. THE BIRTH RATE OF SNe Ia FROM HYBRID CONe WHITE DWARFS

    SciTech Connect (OSTI)

    Meng, Xiangcun [Yunnan Observatories, Chinese Academy of Sciences, Kunming 650011 (China); Podsiadlowski, Philipp, E-mail: xiangcunmeng@ynao.ac.cn [Department of Astronomy, Oxford University, Oxford OX1 3RH (United Kingdom)

    2014-07-10

    Considering the uncertainties of the C-burning rate (CBR) and the treatment of convective boundaries, Chen et al. found that there is a regime where it is possible to form hybrid CONe white dwarfs (WDs), i.e., ONe WDs with carbon-rich cores. As these hybrid WDs can be as massive as 1.30 M {sub ?}, not much mass needs to be accreted for these objects to reach the Chandrasekhar limit and to explode as Type Ia supernovae (SNe Ia). We have investigated their contribution to the overall SN Ia birth rate and found that such SNe Ia tend to be relatively young with typical time delays between 0.1 and 1 Gyr, where some may be as young as 30 Myr. SNe Ia from hybrid CONe WDs may contribute several percent to all SNe Ia, depending on the common-envelope ejection efficiency and the CBR. We suggest that these SNe Ia may produce part of the 2002cx-like SN Ia class.

  9. Bolometric Light Curves of Type Ia Supernovae G. Contardo 1;2 , B. Leibundgut 1

    E-Print Network [OSTI]

    Leibundgut, Bruno

    Bolometric Light Curves of Type Ia Supernovae G. Contardo 1;2 , B. Leibundgut 1 1 European Southern, Karl­Schwarzschild­Straße 1, D­85748 Garch­ ing, Germany 1.1 Light Curves of Type Ia Supernovae Substantial information about the processes in supernovae is contained in their light curves. They track

  10. Measurement of Omega_m, Omega_Lambda from a blind analysis of Type Ia supernovae with CMAGIC: Using color information to verify the acceleration of the Universe

    E-Print Network [OSTI]

    2006-01-01

    analysis of Type Ia supernovae with CMAGIC: Using colorof 21 high redshift supernovae using a new technique (lightcurves of Type Ia supernovae, ?rst introduced in Wang

  11. Reservoir characterization of the Smackover Formation in southwest Alabama

    SciTech Connect (OSTI)

    Kopaska-Merkel, D.C.; Hall, D.R.; Mann, S.D.; Tew, B.H.

    1993-02-01

    The Upper Jurassic Smackover Formation is found in an arcuate belt in the subsurface from south Texas to panhandle Florida. The Smackover is the most prolific hydrocarbon-producing formation in Alabama and is an important hydrocarbon reservoir from Florida to Texas. In this report Smackover hydrocarbon reservoirs in southwest Alabama are described. Also, the nine enhanced- and improved-recovery projects that have been undertaken in the Smackover of Alabama are evaluated. The report concludes with recommendations about potential future enhanced- and improved-recovery projects in Smackover reservoirs in Alabama and an estimate of the potential volume of liquid hydrocarbons recoverable by enhanced- and improved-recovery methods from the Smackover of Alabama.

  12. Supernova progenitor constraints from circumstellar interaction: Type Ia

    E-Print Network [OSTI]

    Peter Lundqvist; Robert J. Cumming

    1996-10-03

    Searching for the presence of a circumstellar medium is a direct observational way to discriminate between different types of progenitor systems for Type Ia supernovae. We have modeled whether such gas may give rise to detectable emission, especially in H-alpha, and compare the models with observations of SN 1994D. We obtain a mass loss rate less than about 2.5 10^{-5} solar masses per year for a wind speed of 10 km/s. We find that X-ray observations in the range 5-10 keV, e.g., with AXAF, provide the most useful limits on the mass loss, while high-resolution optical spectroscopy offers the only direct way of identifying circumstellar hydrogen.

  13. Random Walker Ranking for NCAA Division I-A Football

    E-Print Network [OSTI]

    Callaghan, T; Mucha, P J; Callaghan, Thomas; Porter, Mason A.; Mucha, Peter J.

    2003-01-01

    We develop a one-parameter family of ranking systems for NCAA Division I-A football teams based on a collection of voters, each with a single vote, executing independent random walks on a network defined by the teams (vertices) and the games played (edges). The virtue of this class of ranking systems lies in the simplicity of its explanation. We discuss the statistical properties of the randomly walking voters and relate them to the community structure of the underlying network. We compare the results of these rankings for recent seasons with Bowl Championship Series standings and component rankings. To better understand this ranking system, we also examine the asymptotic behaviors of the aggregate of walkers. Finally, we consider possible generalizations to this ranking algorithm.

  14. No evidence for bulk velocity from type Ia supernovae

    E-Print Network [OSTI]

    Huterer, Dragan; Schmidt, Fabian

    2015-01-01

    We revisit the effect of peculiar velocities on low-redshift type Ia supernovae. Velocities introduce an additional guaranteed source of correlations between supernova magnitudes that should be considered in all analyses of nearby supernova samples but has largely been neglected in the past. Applying a likelihood analysis to the latest compilation of nearby supernovae, we find no evidence for the presence of these correlations, although, given the significant noise, the data is also consistent with the correlations predicted for the standard LCDM model. We then consider the dipolar component of the velocity correlations - the frequently studied "bulk velocity" - and explicitly demonstrate that including the velocity correlations in the data covariance matrix is crucial for drawing correct and unambiguous conclusions about the bulk flow. In particular, current supernova data is consistent with no excess bulk flow on top of what is expected in LCDM and effectively captured by the covariance. We further clarify ...

  15. On Measuring the Metallicity of Supernovae Type Ia Progenitors

    E-Print Network [OSTI]

    Miles, Broxton J; Townsley, Dean M; Timmes, F X; Jackson, Aaron P; Calder, Alan C; Brown, Edward F

    2015-01-01

    In Type Ia Supernovae (\\sneia), the relative abundances of chemical elements are affected by the neutron excess in the composition of the progenitor white dwarf. Since these products leave signatures in the spectra near maximum light, spectral features may be used to constrain the composition of the progenitor. We calculate the nucleosynthetic yields for three \\snia simulations for a wide range of progenitor metallicities, and calculate synthetic light curves and spectra to explore correlations between progenitor metallicity and the strength of spectral features. We use two 2D simulations of the deflagration-detonation-transition scenario with different $^{56}$Ni yields and the W7 simulation to control for differences between explosion models and total yields. While the overall yields of intermediate mass elements (16 $<$ A $\\leq$ 40) differ between the three cases, trends in the yields are similar. With increasing metallicity, $^{28}$Si yields remain nearly constant, $^{40}$Ca yields decline, and Ti and $...

  16. A new hydrodynamics code for Type Ia Supernovae

    E-Print Network [OSTI]

    Leung, S -C; Lin, L -M

    2015-01-01

    A two-dimensional hydrodynamics code for Type Ia supernovae (SNIa) simulations is presented. The code includes a fifth-order shock-capturing scheme WENO, detailed nuclear reaction network, flame-capturing scheme and sub-grid turbulence. For post-processing we have developed a tracer particle scheme to record the thermodynamical history of the fluid elements. We also present a one-dimensional radiative transfer code for computing observational signals. The code solves the Lagrangian hydrodynamics and moment-integrated radiative transfer equations. A local ionization scheme and composition dependent opacity are included. Various verification tests are presented, including standard benchmark tests in one and two dimensions. SNIa models using the pure turbulent deflagration model and the delayed-detonation transition model are studied. The results are consistent with those in the literature. We compute the detailed chemical evolution using the tracer particles' histories, and we construct corresponding bolometric...

  17. Type Ia supernova Hubble residuals and host-galaxy properties

    SciTech Connect (OSTI)

    Kim, A. G.; Aldering, G.; Aragon, C.; Bailey, S.; Fakhouri, H. K. [Physics Division, Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, CA 94720 (United States); Antilogus, P.; Bongard, S.; Canto, A.; Cellier-Holzem, F.; Fleury, M.; Guy, J. [Laboratoire de Physique Nucléaire et des Hautes Énergies, Université Pierre et Marie Curie Paris 6, Université Paris Diderot Paris 7, CNRS-IN2P3, 4 place Jussieu, F-75252 Paris Cedex 05 (France); Baltay, C. [Department of Physics, Yale University, New Haven, CT 06250-8121 (United States); Buton, C.; Feindt, U.; Greskovic, P.; Kowalski, M. [Physikalisches Institut, Universität Bonn, Nußallee 12, D-53115 Bonn (Germany); Childress, M. [Research School of Astronomy and Astrophysics, Australian National University, Canberra, ACT 2611 (Australia); Chotard, N.; Copin, Y.; Gangler, E. [Université de Lyon, F-69622 Lyon (France); Université de Lyon 1, Villeurbanne (France); CNRS/IN2P3, Institut de Physique Nucléaire de Lyon (France); and others

    2014-03-20

    Kim et al. introduced a new methodology for determining peak-brightness absolute magnitudes of type Ia supernovae from multi-band light curves. We examine the relation between their parameterization of light curves and Hubble residuals, based on photometry synthesized from the Nearby Supernova Factory spectrophotometric time series, with global host-galaxy properties. The K13 Hubble residual step with host mass is 0.013 ± 0.031 mag for a supernova subsample with data coverage corresponding to the K13 training; at <<1?, the step is not significant and lower than previous measurements. Relaxing the data coverage requirement of the Hubble residual step with the host mass is 0.045 ± 0.026 mag for the larger sample; a calculation using the modes of the distributions, less sensitive to outliers, yields a step of 0.019 mag. The analysis of this article uses K13 inferred luminosities, as distinguished from previous works that use magnitude corrections as a function of SALT2 color and stretch parameters: steps at >2? significance are found in SALT2 Hubble residuals in samples split by the values of their K13 x(1) and x(2) light-curve parameters. x(1) affects the light-curve width and color around peak (similar to the ?m {sub 15} and stretch parameters), and x(2) affects colors, the near-UV light-curve width, and the light-curve decline 20-30 days after peak brightness. The novel light-curve analysis, increased parameter set, and magnitude corrections of K13 may be capturing features of SN Ia diversity arising from progenitor stellar evolution.

  18. On silicon group elements ejected by supernovae type IA

    SciTech Connect (OSTI)

    De, Soma; Timmes, F. X. [School of Earth and Space Exploration, Arizona State University, Tempe, AZ (United States); Brown, Edward F. [Joint Institute for Nuclear Astrophysics, University of Notre Dame, IN 46556 (United States); Calder, Alan C. [Department of Physics and Astronomy, Stony Brook University, Stony Brook, NY (United States); Townsley, Dean M. [Department of Physics and Astronomy, The University of Alabama, Tuscaloosa, AL (United States); Athanassiadou, Themis [Swiss National Supercomputing Centre, Via Trevano 131, 6900 Lugano (Switzerland); Chamulak, David A. [Physics Division, Argonne National Laboratory, Argonne, IL (United States); Hawley, Wendy [Laboratoire d'Astrophysique de Marseille, Marseille cedex 13 F-13388 (France); Jack, Dennis, E-mail: somad@asu.edu [Departamento de Astronomía, Universidad de Guanajuato, Apartado Postal 144, 36000 Guanajuato (Mexico)

    2014-06-01

    There is evidence that the peak brightness of a Type Ia supernova is affected by the electron fraction Y {sub e} at the time of the explosion. The electron fraction is set by the aboriginal composition of the white dwarf and the reactions that occur during the pre-explosive convective burning. To date, determining the makeup of the white dwarf progenitor has relied on indirect proxies, such as the average metallicity of the host stellar population. In this paper, we present analytical calculations supporting the idea that the electron fraction of the progenitor systematically influences the nucleosynthesis of silicon group ejecta in Type Ia supernovae. In particular, we suggest the abundances generated in quasi-nuclear statistical equilibrium are preserved during the subsequent freeze-out. This allows potential recovery of Y {sub e} at explosion from the abundances recovered from an observed spectra. We show that measurement of {sup 28}Si, {sup 32}S, {sup 40}Ca, and {sup 54}Fe abundances can be used to construct Y {sub e} in the silicon-rich regions of the supernovae. If these four abundances are determined exactly, they are sufficient to recover Y {sub e} to 6%. This is because these isotopes dominate the composition of silicon-rich material and iron-rich material in quasi-nuclear statistical equilibrium. Analytical analysis shows the {sup 28}Si abundance is insensitive to Y {sub e}, the {sup 32}S abundance has a nearly linear trend with Y {sub e}, and the {sup 40}Ca abundance has a nearly quadratic trend with Y {sub e}. We verify these trends with post-processing of one-dimensional models and show that these trends are reflected in the model's synthetic spectra.

  19. The cosmic rate of supernovae and the range of stars ending as Type Ia SNe

    E-Print Network [OSTI]

    P. Ruiz-Lapuente; R. Canal

    2000-09-20

    The present cosmic rate of Type Ia supernovae (SNeIa) suggests that about 6% of all stars in binary systems with primaries in the initial mass range $3-9\\ M\\sun$ end up as SNeIa. If that is confirmed, the unavoidable conclusion is that SNeIa can only be explained by the single degenerate scenario. At most 1% of stars in binary systems in the above range end up as CO + CO WD pairs, with total mass equal to or larger than the Chandrasekhar mass. Given that the number of mergers from pairs of CO + He WDs that reach the Chandrasekhar mass is even lower, the conclusion strongly favors binaries containing just one CO WD as the progenitors of SNeIa, since the SNeIa production efficiency (relative to the instantaneous star formation rate) predicted for double degenerate (DD) pairs lies more than $3\\sigma$ below the observational data, and the DD scenario can be rejected at more than 99% confidence level. Only if the SFR measurements from $z\\sim 0.1$ to $z\\sim 0.5$ are being underestimated by a factor of 6 while SNeIa rates are not, can we escape the above conclusion. We evaluate the numbers and characteristics of double WD systems with different chemical compositions (CO and He WDs) that should form and compare them with the observations, in order to check our predictions. Our conclusions appear robust after that test.

  20. Stellar Populations and the White Dwarf Mass Function: Connections To Supernova Ia Luminosities

    E-Print Network [OSTI]

    Ted von Hippel; G. D. Bothun; R. A. Schommer

    1997-06-11

    We discuss the luminosity function of SNe Ia under the assumption that recent evidence for dispersion in this standard candle is related to variations in the white dwarf mass function (WDMF) in the host galaxies. We develop a simple parameterization of the WDMF as a function of age of a stellar population and apply this to galaxies of different morphological types. We show that this simplified model is consistent with the observed WDMF of Bergeron et al. (1992) for the solar neighborhood. Our simple models predict that WDMF variations can produce a range of more than 1.8 mag in M$_B$(SN Ia), which is comparable to the observed value using the data of Phillips (1993) and van den Bergh (1996). We also predict a galaxy type dependence of M$_B$(SN Ia) under standard assumptions of the star formation history in these galaxies and show that M$_B$(SN Ia) can evolve with redshift. In principle both evolutionary and galaxy type corrections should be applied to recover the intrinsic range of M$_B$(SN Ia) from the observed values. Our current inadequate knowledge of the star formation history of galaxies coupled with poor physical understanding of the SN Ia mechanism makes the reliable estimation of these corrections both difficult and controversial. The predictions of our models combined with the observed galaxy and redshift correlations may have the power to discriminate between the Chandrasekhar and the sub-Chandrasekhar progenitor scenarios for SNe Ia.

  1. The Hubble Constant from Type Ia Supernovae in Early-Type Galaxies

    E-Print Network [OSTI]

    Tom Richtler; Georg Drenkhahn

    1999-09-07

    Type Ia supernovae (SNe) are the best standard candles available today in spite of an appreciable intrinsic variation of their luminosities at maximum phase, and of probably non-uniform progenitors. For an unbiased use of type Ia SNe as distance indicators it is important to know accurately how the decline rate and colour at maximum phase correlate with the peak brightness. In order to calibrate the Hubble diagram of type Ia SNe, i.e. to derive the Hubble constant, one needs to determine the absolute brightness of nearby type Ia SNe. Globular cluster systems of early type Ia host galaxies provide suitable distance indicators. We discuss how Ia SNe can be calibrated and explain the method of Globular Cluster Luminosity Functions (GCLFs). At present, the distance to the Fornax galaxy cluster is most important for deriving the Hubble constant. Our present data indicate a Hubble constant of H_0=72+-4 km/s/Mpc. As an appendix, we summarise what is known about absolute magnitudes of Ia's in late-type galaxies.

  2. Transformations of Spanish urban landscapes in the American Southwest, 1821-1900

    E-Print Network [OSTI]

    Brew, Nina V

    1986-01-01

    Through an examination of changes in urban structure and building form, I will consider the continuity of historical Spanish urban form in the American Southwest. The study encompasses three phases of increasing Anglo ...

  3. The War in the Desert: The Vietnam Antiwar Movement in the American Southwest 

    E-Print Network [OSTI]

    Ward, Brandon M.

    2010-10-12

    The Vietnam antiwar movement developed in the American Southwest out of a coalition of Chicanos, GI's, and students who agreed that the Vietnam War was racist, imperialist, costly, and negatively affected them and their communities. The antiwar...

  4. VP of Transmission System Asset Management for Desert Southwest Region (Maintenance Manager)

    Broader source: Energy.gov [DOE]

    (See Frequently Asked Questions for more information). Where would I be working? Western Area Power Administration Desert Southwest Region Maintenance (G5000) 615 S. 43rd Avenue Phoenix, AZ 85009...

  5. Characterization of Miocene-Pliocene carbonate platforms, southern Southwest Palawan Basin, Philippines 

    E-Print Network [OSTI]

    Sta. Ana, Ma. Corazon Victor

    2009-06-02

    Isolated carbonate platforms and buildups of the Likas Formation provide a long record of carbonate sedimentation in the southern end of the Southwest Palawan Basin. While most carbonate platforms terminated in early Miocene and middle Miocene time...

  6. A STUDY OF PROPERTIES OF TYPE IA SUPERNOVA AND THE CALIBRATION OF MULTIBAND PHOTOMETRY 

    E-Print Network [OSTI]

    Bastola, Deepak 1988-

    2012-04-27

    The peak luminosity of Type Ia Supernova (SN) can be calibrated using a distance independent luminosity parameter called the decline rate parameter (?m15 (B) to get accurate distances to the galaxies. The photometry gathered from the telescopes...

  7. SALT2: using distant supernovae to improve the use of Type Ia supernovae as distance indicators

    E-Print Network [OSTI]

    J. Guy; P. Astier; S. Baumont; D. Hardin; R. Pain; N. Regnault; S. Basa; R. G. Carlberg; A. Conley; S. Fabbro; D. Fouchez; I. M. Hook; D. A. Howell; K. Perrett; C. J. Pritchet; J. Rich; M. Sullivan; P. Antilogus; E. Aubourg; G. Bazin; J. Bronder; M. Filiol; N. Palanque-Delabrouille; P. Ripoche; V. Ruhlmann-Kleider

    2007-01-29

    We present an empirical model of Type Ia supernovae spectro-photometric evolution with time. The model is built using a large data set including light-curves and spectra of both nearby and distant supernovae, the latter being observed by the SNLS collaboration. We derive the average spectral sequence of Type Ia supernovae and their main variability components including a color variation law. The model allows us to measure distance moduli in the spectral range 2500-8000 A with calculable uncertainties, including those arising from variability of spectral features. Thanks to the use of high-redshift SNe to model the rest-frame UV spectral energy distribution, we are able to derive improved distance estimates for SNe Ia in the redshift range 0.8Ia supernovae.

  8. submitted to ApJ Direct Numerical Simulations of Type Ia Supernovae Flames I

    E-Print Network [OSTI]

    Bell, John B.

    for C/O thermonuclear flames at conditions relevant to the late stages of a Type Ia supernova explosion and results relevant for thermonuclear flames. Sivashinsky (1977) and Michelson & Sivashinsky (1977) studied

  9. Quantitative comparison between Type Ia supernova spectra at low and high redshifts: A case study

    E-Print Network [OSTI]

    Garavini, G.; Supernova Cosmology Project

    2008-01-01

    Highlight - The Physics of Supernovae, ESO/MPA/MPE Workshop,Evolution in high-redshift supernovae Fig. 8 “Ca ii H&K”SN 1991T/SN 1999aa-like supernovae. 1. Introduction Type Ia

  10. Imprint of modified Einstein's gravity on white dwarfs: Unifying type Ia supernovae

    E-Print Network [OSTI]

    Das, Upasana

    2015-01-01

    We establish the importance of modified Einstein's gravity (MG) in white dwarfs (WDs) for the first time in the literature. We show that MG leads to significantly sub- and super-Chandrasekhar limiting mass WDs, depending on a single model parameter. However, conventional WDs on approaching Chandrasekhar's limit are expected to trigger type Ia supernovae (SNeIa), a key to unravel the evolutionary history of the universe. Nevertheless, observations of several peculiar, under- and over-luminous SNeIa argue for the limiting mass widely different from Chandrasekhar's limit. Explosions of MG induced sub- and super-Chandrasekhar limiting mass WDs explain under- and over-luminous SNeIa respectively, thus unifying these two apparently disjoint sub-classes. Our discovery questions both the global validity of Einstein's gravity and the uniqueness of Chandrasekhar's limit.

  11. Jou~ia1of Neurochemistry Lippincott--Raven Publishers, Philadelphia

    E-Print Network [OSTI]

    Fischer, Itzhak

    Jou~ia1of Neurochemistry Lippincott--Raven Publishers, Philadelphia © 1997 International Society University, Philadelphia, Pennsylvania, U.S.A. Abstract: MAP 1 B is a microtubule-associated phospho- protein

  12. A Multi-scale Study of Inorganic Aqueous Solution (IAS) for Advanced Heat Pipe Applications

    E-Print Network [OSTI]

    Amouzegar Ashtiani, Ladan

    2015-01-01

    IAS-treated” Vs. “Clean” Cu (Working fluid: 7 mL water) Exp.water (Qu-fluid) fill charge [mL] copper surface clean cleanclean copper” identifies the pertinent experiments “Qu-fluid” (

  13. Type Ia supernovae from merging white dwarfs. II. Post-merger...

    Office of Scientific and Technical Information (OSTI)

    out multidimensional simulations of 'tamped' SN Ia models, using both particle and grid-based codes to study the merger and explosion dynamics and a radiative transfer code to...

  14. Tectonic control of coastal onlap cycles, southwest Washington

    SciTech Connect (OSTI)

    Armentrout, J.M.

    1987-05-01

    Local coastal onlap and paleobiobathymetric curves for 14 sections define three Cenozoic depositional onlap-offlap cycles separated by regionally significant unconformities. A paleoclimatic curve for western Oregon and Washington, based on paleoecologic data sets, demonstrates that the local transgressions are coincident with cool climates and the regressions with warm climates, and are therefore not driven by glacioeustatic cycles. Comparison of the local coastal onlap and paleobiobathymetric curves with the global Cenozoic Cycle Chart (modified Exxon Sea Level Chart - May, 1986) further demonstrates the uniqueness of the western Washington curves. The global Cenozoic cycle Chart curve represents coastal onlap and sea level curves based on integration of both climate and tectonic variations. The non-parallel cycle pattern for southwest Washington suggests a unique tectonically forced system. Evidence derived from stratigraphic sequences, igneous rock geochemistry, radiometric dating, remnant magnetic patterns, sandstone provenance studies, and paleogeographic reconstructions is used to identify the tectonic events controlling the local depositional cycles. The principal events are (1) middle Eocene accretion of a seamount chain; (2) early-late Eocene westward relocation of subduction; (3) late Eocene onset of Cascade arc volcanism; (4) late-early Miocene plate readjustment due to back-arc extension in the Columbia River Plateau and Great Basin; and (5) late Pliocene to early Pleistocene northeast compression forced by continued subduction of remnants of the Kula Plate beneath North America.

  15. Cosmological parameter uncertainties from SALT-II type Ia supernova light curve models

    SciTech Connect (OSTI)

    Mosher, J.; Sako, M. [Department of Physics and Astronomy, University of Pennsylvania, 209 South 33rd Street, Philadelphia, PA 19104 (United States); Guy, J.; Astier, P.; Betoule, M.; El-Hage, P.; Pain, R.; Regnault, N. [LPNHE, CNRS/IN2P3, Université Pierre et Marie Curie Paris 6, Universié Denis Diderot Paris 7, 4 place Jussieu, F-75252 Paris Cedex 05 (France); Kessler, R.; Frieman, J. A. [Kavli Institute for Cosmological Physics, University of Chicago, 5640 South Ellis Avenue, Chicago, IL 60637 (United States); Marriner, J. [Center for Particle Astrophysics, Fermi National Accelerator Laboratory, P.O. Box 500, Batavia, IL 60510 (United States); Biswas, R.; Kuhlmann, S. [Argonne National Laboratory, 9700 South Cass Avenue, Lemont, IL 60439 (United States); Schneider, D. P., E-mail: kessler@kicp.chicago.edu [Department of Astronomy and Astrophysics, The Pennsylvania State University, University Park, PA 16802 (United States)

    2014-09-20

    We use simulated type Ia supernova (SN Ia) samples, including both photometry and spectra, to perform the first direct validation of cosmology analysis using the SALT-II light curve model. This validation includes residuals from the light curve training process, systematic biases in SN Ia distance measurements, and a bias on the dark energy equation of state parameter w. Using the SN-analysis package SNANA, we simulate and analyze realistic samples corresponding to the data samples used in the SNLS3 analysis: ?120 low-redshift (z < 0.1) SNe Ia, ?255 Sloan Digital Sky Survey SNe Ia (z < 0.4), and ?290 SNLS SNe Ia (z ? 1). To probe systematic uncertainties in detail, we vary the input spectral model, the model of intrinsic scatter, and the smoothing (i.e., regularization) parameters used during the SALT-II model training. Using realistic intrinsic scatter models results in a slight bias in the ultraviolet portion of the trained SALT-II model, and w biases (w {sub input} – w {sub recovered}) ranging from –0.005 ± 0.012 to –0.024 ± 0.010. These biases are indistinguishable from each other within the uncertainty; the average bias on w is –0.014 ± 0.007.

  16. Measuring nickel masses in Type Ia supernovae using cobalt emission in nebular phase spectra

    E-Print Network [OSTI]

    Childress, Michael J; Seitenzahl, Ivo; Sullivan, Mark; Maguire, Kate; Taubenberger, Stefan; Scalzo, Richard; Ruiter, Ashley; Blagorodnova, Nadejda; Camacho, Yssavo; Castillo, Jayden; Elias-Rosa, Nancy; Fraser, Morgan; Gal-Yam, Avishay; Graham, Melissa; Howell, D Andrew; Inserra, Cosimo; Jha, Saurabh W; Kumar, Sahana; Mazzali, Paolo A; McCully, Curtis; Morales-Garoffolo, Antonia; Pandya, Viraj; Polshaw, Joe; Schmidt, Brian; Smartt, Stephen; Smith, Ken W; Sollerman, Jesper; Spyromilio, Jason; Tucker, Brad; Valenti, Stefano; Walton, Nicholas; Wolf, Christian; Yaron, Ofer; Young, D R; Yuan, Fang; Zhang, Bonnie

    2015-01-01

    The light curves of Type Ia supernovae (SNe Ia) are powered by the radioactive decay of $^{56}$Ni to $^{56}$Co at early times, and the decay of $^{56}$Co to $^{56}$Fe from ~60 days after explosion. We examine the evolution of the [Co III] 5892 A emission complex during the nebular phase for SNe Ia with multiple nebular spectra and show that the line flux follows the square of the mass of $^{56}$Co as a function of time. This result indicates both efficient local energy deposition from positrons produced in $^{56}$Co decay, and long-term stability of the ionization state of the nebula. We compile 77 nebular spectra of 25 SN Ia from the literature and present 17 new nebular spectra of 7 SNe Ia, including SN2014J. From these we measure the flux in the [Co III] 5892 A line and remove its well-behaved time dependence to infer the initial mass of $^{56}$Ni ($M_{Ni}$) produced in the explosion. We then examine $^{56}$Ni yields for different SN Ia ejected masses ($M_{ej}$ - calculated using the relation between light...

  17. Rates, Progenitors and Cosmic Mix of Type Ia Supernovae

    E-Print Network [OSTI]

    Laura Greggio; Alvio Renzini; Emanuele Daddi

    2008-05-29

    Following an episode of star formation, Type Ia supernova events occur over an extended period of time, following a distribution of delay times (DDT). We critically discuss some empirically-based DDT functions that have been proposed in recent years, some favoring very early (prompt) events, other very late (tardy) ones, and therefore being mutually exclusive. We point out that in both cases the derived DDT functions are affected by dubious assumptions, and therefore there is currently no ground for claiming either a DDT strongly peaked at early times, or at late ones. Theoretical DDT functions are known to accommodate both prompt as well as late SNIa events, and can account for all available observational constraints. Recent observational evidence exists that both single degenerate and double degenerate precursors may be able of producing SNIa events. We then explore on the basis of plausible theoretical models the possible variation with cosmic time of the mix between the events produced by the two different channels, which in principle could lead to systematics effects on the SNIa properties with redshift.

  18. The rates of Type Ia Supernovae. I. Analytical Formulations

    E-Print Network [OSTI]

    Laura Greggio

    2005-04-29

    This paper provides a handy tool to compute the impact of Type Ia Supernova (SNIa) on the evolution of stellar systems. An effective formalism is presented to couple the SNIa rate to the star formation history, which rests upon the definition of two key properties of the progenitor's model: the realization probability of the SNIa event from a single stellar generation and the distribution function of the delay times. It is shown that the current SNIa rate in late type galaxies implies that the realization probability is on the order of 0.001. Analytical formulations for the distribution function of the delay times for Single (SD) and Double Degenerate (DD) progenitors are derived, based on stellar evolution arguments. These formulations, which agree well with the results of Monte Carlo simulations for the evolution of close binaries, have a built in parametrization of the key properties of the alternative candidates. The various models for the progenitors have different impact on the large scales. In particular, the paper examines the systematic trend of the SNIa rate per unit mass with the color of the parent galaxy, and shows that the recent observations favor the DD model. The SD scenario can reproduce the data only if the distribution of the primordial mass ratios is flat, and the accretion efficiency onto the WD is close to 100%. The timescale for the Fe release from SNIa to the interstellar medium ranges between 0.3 and 3 Gyr for a wide variety of hypothesis on the SNIa progenitors. (ABRIDGED)

  19. The Diurnal Path of the Sun: Ideology and Interregional Interaction in Ancient Northwest Mesoamerica and the American Southwest

    E-Print Network [OSTI]

    Mathiowetz, Michael Dean

    2011-01-01

    Postclassic wind god of highland Central Mexico. In recentlyand wind aspect Ehecatl) in highland Central Mexico, areMogollon Wind Mountain site in southwest New Mexico revealed

  20. The Diurnal Path of the Sun: Ideology and Interregional Interaction in Ancient Northwest Mesoamerica and the American Southwest

    E-Print Network [OSTI]

    Mathiowetz, Michael Dean

    2011-01-01

    impact of the West Mexican Aztatlán culture and cosmology on social transformations that occurred in the North American Southwest and northern Mexico

  1. Utilizing Type Ia Supernovae in a Large, Fast, Imaging Survey to Constrain Dark Energy

    E-Print Network [OSTI]

    Andrew R. Zentner; Suman Bhattacharya

    2008-12-01

    We study the utility of a large sample of type Ia supernovae that might be observed in an imaging survey that rapidly scans a large fraction of the sky for constraining dark energy. We consider information from the traditional luminosity distance test as well as the spread in SNeIa fluxes at fixed redshift induced by gravitational lensing. We include a treatment of photometric redshift uncertainties in our analysis. Our primary result is that the information contained in the mean distance moduli of SNeIa and the dispersion among SNeIa distance moduli complement each other, breaking a degeneracy between the present dark energy equation of state and its time variation without the need for a high-redshift supernova sample. To address photometric redshift uncertainties, we present dark energy constraints as a function of the size of an external set of spectroscopically-observed SNeIa that may be used for redshift calibration, nspec. We find that an imaging survey can constrain the dark energy equation of state at the epoch where it is best constrained with a 1-sigma error of sigma(wpiv)~0.03-0.09$, depending upon various assumptions. In addition, the marginal improvement in the error sigma(wpiv) from an increase in the spectroscopic calibration sample drops once nspec ~ 10^3. This result is important because it is of the order of the size of calibration samples likely to be compiled in the coming decade and because, for samples of this size, the spectroscopic and imaging surveys individually place comparable constraints on the dark energy equation of state. In all cases, it is best to calibrate photometric redshifts with a set of spectroscopically-observed SNeIa with relatively more objects at high redshift than the parent sample of imaging SNeIa.

  2. The type Ia supernova SNLS-03D3bb from a super-Chandrasekhar-mass white dwarf star

    E-Print Network [OSTI]

    2008-01-01

    magnitudes of Type IA supernovae. Astrophys. J. Lett. 413,from 42 High-Redshift Supernovae. Astrophys. J. 517, 565–Observational Evidence from Supernovae for an Accelerating

  3. A New Determination of the High Redshift Type Ia Supernova Rates with the Hubble Space Telescope Advanced Camera for Surveys

    E-Print Network [OSTI]

    2008-01-01

    Schmidt, B. P. , 2003, in Supernovae and Gamma Ray Bursts,for identifying Type Ia supernovae (although spectroscopicfor future high-statistics supernovae searches in which

  4. flray Transport in Type Ia In order to solve the rate equations in a consistent manner, PHOENIX must include

    E-Print Network [OSTI]

    Nugent, Peter

    in a consistent manner, PHOENIX must include the effects of non­thermal ionization. In Type Ia supernovae the non

  5. One-way coupling of an integrated assessment model and a water resources model: evaluation and implications of future changes over the US Midwest

    SciTech Connect (OSTI)

    Voisin, Nathalie; Liu, Lu; Hejazi, Mohamad I.; Tesfa, Teklu K.; Li, Hongyi; Huang, Maoyi; Liu, Ying; Leung, Lai-Yung R.

    2013-11-18

    An integrated model is being developed to advance our understanding of the interactions between human activities, terrestrial system and water cycle, and how system interactions will be affected by a changing climate at the regional scale. As a first step towards that goal, a global integrated assessment model including a waterdemand model is coupled offline with a land surface hydrology – routing – water resources management model. A spatial and temporal disaggregation approach is developed to project the annual regional water demand simulations into a daily time step and subbasin representation. The model demonstrated reasonable ability to represent the historical flow regulation and water supply over the Midwest (Missouri, Upper Mississippi and Ohio). Implications for the future flow regulation, water supply and supply deficit are investigated using a climate change projection with the B1 emission scenario which affects both natural flow and water demand. Over the Midwest, changes in flow regulation are mostly driven by the change in natural flow due to the limited storage capacity over the Ohio and Upper Mississippi river basins. The changes in flow and demand have a combined effect on the Missouri Summer regulated flow. The supply deficit tends to be driven by the change in flow over the region. Spatial analysis demonstrates the relationship between the supply deficit and the change in demand over urban areas not along a main river or with limited storage, and over areas upstream of groundwater dependent fields with therefore overestimated demand.

  6. Wind-driven evolution of white dwarf binaries to type Ia supernovae

    SciTech Connect (OSTI)

    Ablimit, Iminhaji; Xu, Xiao-jie; Li, X.-D. [Department of Astronomy, Nanjing University, Nanjing 210093 (China)

    2014-01-01

    In the single-degenerate scenario for the progenitors of Type Ia supernovae (SNe Ia), a white dwarf rapidly accretes hydrogen- or helium-rich material from its companion star and appears as a supersoft X-ray source. This picture has been challenged by the properties of the supersoft X-ray sources with very low mass companions and the observations of several nearby SNe Ia. It has been pointed out that the X-ray radiation or the wind from the accreting white dwarf can excite winds or strip mass from the companion star, thus significantly influencing the mass transfer processes. In this paper, we perform detailed calculations of the wind-driven evolution of white dwarf binaries. We present the parameter space for the possible SN Ia progenitors and for the surviving companions after the SNe. The results show that the ex-companion stars of SNe Ia have characteristics more compatible with the observations, compared with those in the traditional single-degenerate scenario.

  7. CfAIR2: Near Infrared Light Curves of 94 Type Ia Supernovae

    E-Print Network [OSTI]

    Friedman, Andrew S; Marion, G H; Challis, Peter; Mandel, Kaisey S; Bloom, Joshua S; Modjaz, Maryam; Narayan, Gautham; Hicken, Malcolm; Foley, Ryan; Klein, Christopher R; Starr, Dan L; Morgan, Adam; Rest, Armin; Blake, Cullen H; Miller, Adam A; Falco, Emilio E; Wyatt, William F; Mink, Jessica; Skrutskie, Michael F; Kirshner, Robert P

    2014-01-01

    CfAIR2 is a large homogeneously reduced set of near-infrared (NIR) light curves for Type Ia supernovae (SN Ia) obtained with the 1.3m PAIRITEL (Peters Automated InfraRed Imaging TELescope). This data set includes 4607 measurements of 94 SN Ia and 4 additional SN Iax observed from 2005-2011 at the Fred Lawrence Whipple Observatory on Mount Hopkins, Arizona. CfAIR2 includes JHKs photometric measurements for 88 normal and 6 spectroscopically peculiar SN Ia in the nearby universe, with a median redshift of z~0.021 for the normal SN Ia. CfAIR2 data span the range from -13 days to +127 days from maximum in the B-band. More than half of the light curves begin before the time of maximum and the coverage typically contains ~13-18 epochs of observation, depending on the filter. We present extensive tests that verify the fidelity of the CfAIR2 data pipeline, including comparison to the excellent data of the Carnegie Supernova Project. CfAIR2 contributes to a firm local anchor for supernova cosmology studies in the NIR. ...

  8. Optical and NIR observations of the nearby type Ia supernova SN 2014J

    E-Print Network [OSTI]

    Srivastav, Shubham; Kumar, Brajesh; Anupama, G C; Sahu, D K; Ojha, D K; Prabhu, T P

    2016-01-01

    Optical and NIR observations of the type Ia supernova SN 2014J in M82 are presented. The observed light curves are found to be similar to normal SNe Ia, with a decline rate parameter $\\Delta m_{15}(B) = 1.08 \\pm 0.03$. The supernova reached $B$-band maximum on JD 2456690.14, at an apparent magnitude $m_B(max) = 11.94$. The optical spectra show a red continuum with deep interstellar Na~{\\sc i} absorption, but otherwise resemble those of normal SNe Ia. The Si~{\\sc ii} $\\lambda 6355$ feature indicates a velocity of $\\sim 12\\,000$ km s$^{-1}$ at $B$-band maximum, which places SN 2014J at the border of the Normal Velocity and High Velocity group of SNe Ia. The velocity evolution of SN 2014J places it in the Low Velocity Gradient subclass, whereas the equivalent widths of Si~{\\sc ii} features near $B$-band maximum place it at the border of the Core Normal and Broad Line subclasses of SNe Ia. An analytic model fit to the bolometric light curve indicates that a total of $\\sim 1.3$ M$_{\\odot}$ was ejected in the explo...

  9. Type Ia supernovae from merging white dwarfs. II. Post-merger detonations

    SciTech Connect (OSTI)

    Raskin, Cody; Kasen, Daniel [Nuclear Science Division, Lawrence Berkeley National Laboratory, Berkeley, CA (United States); Moll, Rainer; Woosley, Stan [Department of Physics and Department of Astronomy, University of California, Santa Cruz, CA (United States); Schwab, Josiah [Department of Physics and Department of Astronomy, University of California, Berkeley, CA (United States)

    2014-06-10

    Merging carbon-oxygen (CO) white dwarfs are a promising progenitor system for Type Ia supernovae (SNe Ia), but the underlying physics and timing of the detonation are still debated. If an explosion occurs after the secondary star is fully disrupted, the exploding primary will expand into a dense CO medium that may still have a disk-like structure. This interaction will decelerate and distort the ejecta. Here we carry out multidimensional simulations of 'tamped' SN Ia models, using both particle and grid-based codes to study the merger and explosion dynamics and a radiative transfer code to calculate synthetic spectra and light curves. We find that post-merger explosions exhibit an hourglass-shaped asymmetry, leading to strong variations in the light curves with viewing angle. The two most important factors affecting the outcome are the scale height of the disk, which depends sensitively on the binary mass ratio, and the total {sup 56}Ni yield, which is governed by the central density of the remnant core. The synthetic broadband light curves rise and decline very slowly, and the spectra generally look peculiar, with weak features from intermediate mass elements but relatively strong carbon absorption. We also consider the effects of the viscous evolution of the remnant and show that a longer time delay between merger and explosion probably leads to larger {sup 56}Ni yields and more symmetrical remnants. We discuss the relevance of this class of aspherical 'tamped' SN Ia for explaining the class of 'super-Chandrasekhar' SN Ia.

  10. COMPARING THE LIGHT CURVES OF SIMULATED TYPE Ia SUPERNOVAE WITH OBSERVATIONS USING DATA-DRIVEN MODELS

    SciTech Connect (OSTI)

    Diemer, Benedikt; Kessler, Richard; Graziani, Carlo; Jordan, George C. IV; Lamb, Donald Q.; Long, Min; Van Rossum, Daniel R., E-mail: bdiemer@oddjob.uchicago.edu [Flash Center for Computational Science, University of Chicago, Chicago, IL 60637 (United States)

    2013-08-20

    We propose a robust, quantitative method to compare the synthetic light curves of a Type Ia supernova (SN Ia) explosion model with a large set of observed SNe Ia, and derive a figure of merit for the explosion model's agreement with observations. The synthetic light curves are fit with the data-driven model SALT2 which returns values for stretch, color, and magnitude at peak brightness, as well as a goodness-of-fit parameter. Each fit is performed multiple times with different choices of filter bands and epoch range in order to quantify the systematic uncertainty on the fitted parameters. We use a parametric population model for the distribution of observed SN Ia parameters from large surveys, and extend it to represent red, dim, and bright outliers found in a low-redshift SN Ia data set. We discuss the potential uncertainties of this population model and find it to be reliable given the current uncertainties on cosmological parameters. Using our population model, we assign each set of fitted parameters a likelihood of being observed in nature, and a figure of merit based on this likelihood. We define a second figure of merit based on the quality of the light curve fit, and combine the two measures into an overall figure of merit for each explosion model. We compute figures of merit for a variety of one-, two-, and three-dimensional explosion models and show that our evaluation method allows meaningful inferences across a wide range of light curve quality and fitted parameters.

  11. The Host Galaxies of Type Ia Supernovae Discovered by the Palomar Transient Factory

    E-Print Network [OSTI]

    Pan, Y -C; Maguire, K; Hook, I M; Nugent, P E; Howell, D A; Arcavi, I; Botyanszki, J; Cenko, S B; DeRose, J; Fakhouri, H K; Gal-Yam, A; Hsiao, E; Kulkarni, S R; Laher, R R; Lidman, C; Nordin, J; Walker, E S; Xu, D

    2013-01-01

    We present spectroscopic observations of the host galaxies of 82 low-redshift type Ia supernovae (SNe Ia) discovered by the Palomar Transient Factory (PTF). We determine star-formation rates, gas-phase/stellar metallicities, and stellar masses and ages of these objects. As expected, strong correlations between the SN Ia light-curve width (stretch) and the host age/mass/metallicity are found: fainter, faster-declining events tend to be hosted by older/massive/metal-rich galaxies. There is some evidence that redder SNe Ia explode in higher metallicity galaxies, but we found no relation between the SN colour and host galaxy extinction based on the Balmer decrement, suggesting that the colour variation of these SNe does not primarily arise from this source. SNe Ia in higher-mass/metallicity galaxies also appear brighter after stretch/colour corrections than their counterparts in lower mass hosts, and the stronger correlation is with gas-phase metallicity suggesting this may be the more important variable. We also...

  12. Site Characterization Activities with a focus on NETL MMV efforts: Southwest Regional Partnership, San Juan Basin Pilot, New Mexico

    E-Print Network [OSTI]

    Wilson, Thomas H.

    Regional Carbon Sequestration Partnership's San Juan Basin pilot site to aid in the deploymentSite Characterization Activities with a focus on NETL MMV efforts: Southwest Regional Partnership Juan Basin of northwestern New Mexico as part of the Southwest Regional Partnership's (SWP) pilot

  13. Low Mach Number Modeling of Type Ia Supernovae. II. Energy Evolution

    E-Print Network [OSTI]

    A. S. Almgren; J. B. Bell; C. A. Rendleman; M. Zingale

    2006-06-21

    The convective period leading up to a Type Ia supernova (SN Ia) explosion is characterized by very low Mach number flows, requiring hydrodynamical methods well-suited to long-time integration. We continue the development of the low Mach number equation set for stellar scale flows by incorporating the effects of heat release due to external sources. Low Mach number hydrodynamics equations with a time-dependent background state are derived, and a numerical method based on the approximate projection formalism is presented. We demonstrate through validation with a fully compressible hydrodynamics code that this low Mach number model accurately captures the expansion of the stellar atmosphere as well as the local dynamics due to external heat sources. This algorithm provides the basis for an efficient simulation tool for studying the ignition of SNe Ia.

  14. Spectral Modeling of SNe Ia Near Maximum Light: Probing the Characteristics of Hydro Models

    E-Print Network [OSTI]

    E. Baron; S. Bongard; David Branch; Peter H. Hauschildt

    2006-03-03

    We have performed detailed NLTE spectral synthesis modeling of 2 types of 1-D hydro models: the very highly parameterized deflagration model W7, and two delayed detonation models. We find that overall both models do about equally well at fitting well observed SNe Ia near to maximum light. However, the Si II 6150 feature of W7 is systematically too fast, whereas for the delayed detonation models it is also somewhat too fast, but significantly better than that of W7. We find that a parameterized mixed model does the best job of reproducing the Si II 6150 line near maximum light and we study the differences in the models that lead to better fits to normal SNe Ia. We discuss what is required of a hydro model to fit the spectra of observed SNe Ia near maximum light.

  15. [O I] ??6300, 6364 IN THE NEBULAR SPECTRUM OF A SUBLUMINOUS TYPE Ia SUPERNOVA

    SciTech Connect (OSTI)

    Taubenberger, S.; Kromer, M.; Hillebrandt, W. [Max-Planck-Institut für Astrophysik, Karl-Schwarzschild-Str. 1, D-85741 Garching (Germany)] [Max-Planck-Institut für Astrophysik, Karl-Schwarzschild-Str. 1, D-85741 Garching (Germany); Pakmor, R. [Heidelberger Institut für Theoretische Studien, Schloss-Wolfsbrunnenweg 35, D-69118 Heidelberg (Germany)] [Heidelberger Institut für Theoretische Studien, Schloss-Wolfsbrunnenweg 35, D-69118 Heidelberg (Germany); Pignata, G. [Departamento de Ciencias Fisicas, Universidad Andres Bello, Avda. Republica 252, Santiago (Chile)] [Departamento de Ciencias Fisicas, Universidad Andres Bello, Avda. Republica 252, Santiago (Chile); Maeda, K. [Kavli Institute for the Physics and Mathematics of the Universe (WPI), Todai Institutes for Advanced Study, University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8583 (Japan)] [Kavli Institute for the Physics and Mathematics of the Universe (WPI), Todai Institutes for Advanced Study, University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8583 (Japan); Hachinger, S. [Julius-Maximilians-Universität Würzburg, Emil-Fischer-Str. 31, D-97074 Würzburg (Germany)] [Julius-Maximilians-Universität Würzburg, Emil-Fischer-Str. 31, D-97074 Würzburg (Germany); Leibundgut, B. [European Southern Observatory, Karl-Schwarzschild-Str. 2, D-85748 Garching (Germany)] [European Southern Observatory, Karl-Schwarzschild-Str. 2, D-85748 Garching (Germany)

    2013-10-01

    In this Letter, a late-phase spectrum of SN 2010lp, a subluminous Type Ia supernova (SN Ia), is presented and analyzed. As in 1991bg-like SNe Ia at comparable epochs, the spectrum is characterized by relatively broad [Fe II] and [Ca II] emission lines. However, instead of narrow [Fe III] and [Co III] lines that dominate the emission from the innermost regions of 1991bg-like supernovae (SNe), SN 2010lp shows [O I] ??6300, 6364 emission, usually associated with core-collapse SNe and never previously observed in a subluminous thermonuclear explosion. The [O I] feature has a complex profile with two strong, narrow emission peaks. This suggests that oxygen is distributed in a non-spherical region close to the center of the ejecta, severely challenging most thermonuclear explosion models discussed in the literature. We conclude that, given these constraints, violent mergers are presently the most promising scenario to explain SN 2010lp.

  16. The Late-Time Rebrightening of Type Ia SN 2005gj in the Mid-Infrared

    E-Print Network [OSTI]

    Fox, Ori D

    2013-01-01

    A growing number of observations reveal a subset of Type Ia supernovae undergoing circumstellar interaction (SNe Ia-CSM). We present unpublished archival Spitzer Space Telescope data on SNe Ia-CSM 2002ic and 2005gj obtained > 1300 and 500 days post-discovery, respectively. Both SNe show evidence for late-time mid-infrared (mid-IR) emission from warm dust. The dust parameters are most consistent with a pre-existing dust shell that lies beyond the forward-shock radius, most likely radiatively heated by optical and X-ray emission continuously generated by late-time CSM interaction. In the case of SN 2005gj, the mid-IR luminosity more than doubles after 1 year post-discovery. While we are not aware of any late-time optical-wavelength observations at these epochs, we attribute this rebrightening to renewed shock interaction with a dense circumstellar shell.

  17. Ultraviolet observations of Super-Chandrasekhar mass type Ia supernova candidates with swift UVOT

    SciTech Connect (OSTI)

    Brown, Peter J.; Smitka, Michael T.; Krisciunas, Kevin; Wang, Lifan [George P. and Cynthia Woods Mitchell Institute for Fundamental Physics and Astronomy, Texas A and M University, Department of Physics and Astronomy, 4242 TAMU, College Station, TX 77843 (United States); Kuin, Paul; De Pasquale, Massimiliano [Mullard Space Science Laboratory, University College London, Holmbury St. Mary, Dorking Surrey, RH5 6NT (United Kingdom); Scalzo, Richard [Research School of Astronomy and Astrophysics, The Australian National University, Mount Stromlo Observatory, Cotter Road, Weston Creek, ACT 2611 (Australia); Holland, Stephen [Space Telescope Science Center 3700 San Martin Drive, Baltimore, MD 21218 (United States); Milne, Peter, E-mail: pbrown@physics.tamu.edu [Steward Observatory, University of Arizona, Tucson, AZ 85719 (United States)

    2014-05-20

    Among Type Ia supernovae (SNe Ia), a class of overluminous objects exist whose ejecta mass is inferred to be larger than the canonical Chandrasekhar mass. We present and discuss the UV/optical photometric light curves, colors, absolute magnitudes, and spectra of three candidate Super-Chandrasekhar mass SNe—2009dc, 2011aa, and 2012dn—observed with the Swift Ultraviolet/Optical Telescope. The light curves are at the broad end for SNe Ia, with the light curves of SN 2011aa being among the broadest ever observed. We find all three to have very blue colors which may provide a means of excluding these overluminous SNe from cosmological analysis, though there is some overlap with the bluest of 'normal' SNe Ia. All three are overluminous in their UV absolute magnitudes compared to normal and broad SNe Ia, but SNe 2011aa and 2012dn are not optically overluminous compared to normal SNe Ia. The integrated luminosity curves of SNe 2011aa and 2012dn in the UVOT range (1600-6000 Å) are only half as bright as SN 2009dc, implying a smaller {sup 56}Ni yield. While it is not enough to strongly affect the bolometric flux, the early time mid-UV flux makes a significant contribution at early times. The strong spectral features in the mid-UV spectra of SNe 2009dc and 2012dn suggest a higher temperature and lower opacity to be the cause of the UV excess rather than a hot, smooth blackbody from shock interaction. Further work is needed to determine the ejecta and {sup 56}Ni masses of SNe 2011aa and 2012dn and to fully explain their high UV luminosities.

  18. Southwest Regional Partnership on Carbon Sequestration Phase II

    SciTech Connect (OSTI)

    James Rutledge

    2011-02-01

    The Southwest Regional Partnership (SWP) on Carbon Sequestration designed and deployed a medium-scale field pilot test of geologic carbon dioxide (CO2) sequestration in the Aneth oil field. Greater Aneth oil field, Utah's largest oil producer, was discovered in 1956 and has produced over 455 million barrels of oil (72 million m3). Located in the Paradox Basin of southeastern Utah, Greater Aneth is a stratigraphic trap producing from the Pennsylvanian Paradox Formation. Because it represents an archetype oil field of the western U.S., Greater Aneth was selected as one of three geologic pilots to demonstrate combined enhanced oil recovery (EOR) and CO2 sequestration under the auspices of the SWP on Carbon Sequestration, sponsored by the U.S. Department of Energy. The pilot demonstration focuced on the western portion of the Aneth Unit as this area of the field was converted from waterflood production to CO2 EOR starting in late 2007. The Aneth Unit is in the northwestern part of the field and has produced 149 million barrels (24 million m3) of the estimated 450 million barrels (71.5 million m3) of the original oil in place - a 33% recovery rate. The large amount of remaining oil makes the Aneth Unit ideal to demonstrate both CO2 storage capacity and EOR by CO2 flooding. This report summarizes the geologic characterization research, the various field monitoring tests, and the development of a geologic model and numerical simulations conducted for the Aneth demonstration project. The Utah Geological Survey (UGS), with contributions from other Partners, evaluated how the surface and subsurface geology of the Aneth Unit demonstration site will affect sequestration operations and engineering strategies. The UGS-research for the project are summarized in Chapters 1 through 7, and includes (1) mapping the surface geology including stratigraphy, faulting, fractures, and deformation bands, (2) describing the local Jurassic and Cretaceous stratigraphy, (3) mapping the Desert Creek zone reservoir, Gothic seal, and overlying aquifers, (4) characterizing the depositional environments and diagenetic events that produced significant reservoir heterogeneity, (5) describing the geochemical, petrographic, and geomechanical properties of the seal to determine the CO2 or hydrocarbon column it could support, and (6) evaluating the production history to compare primary production from vertical and horizontal wells, and the effects of waterflood and wateralternating- gas flood programs. The field monitoring demonstrations were conducted by various Partners including New Mexico Institute of Mining and Technology, University of Utah, National Institute of Advanced Industrial Science and Technology, Japan, Los Alamos National Laboratory and Cambridge Geosciences. The monitoring tests are summarized in Chapters 8 through 12, and includes (1) interwell tracer studies during water- and CO2-flood operations to characterize tracer behavoirs in anticipation of CO2-sequestration applications, (2) CO2 soil flux monitoring to measure background levels and variance and assess the sensitivity levels for CO2 surface monitoring, (3) testing the continuous monitoring of self potential as a means to detect pressure anomalies and electrochemical reaction due to CO2 injection, (4) conducting time-lapse vertical seismic profiling to image change near a CO2 injection well, and (5) monitoring microseismicity using a downhole string of seismic receivers to detect fracture slip and deformation associated with stress changes. Finally, the geologic modeling and numerical simulation study was conducted by researcher at the University of Utah. Chapter 13 summarizes their efforts which focused on developing a site-specific geologic model for Aneth to better understand and design CO2 storage specifically tailored to oil reservoirs.

  19. Reesman, summer 2007 1 Summer 2007 Research on The Effect of Galaxy Properties on Type Ia Supernova

    E-Print Network [OSTI]

    Cinabro, David

    Reesman, summer 2007 1 Summer 2007 Research on The Effect of Galaxy Properties on Type Ia Supernova, we wanted to compare super nova type 1A host galaxy trends to results previously obtained was investigated. Type Ia Supernova are of great interest to cosmologist since they are standardize able candles

  20. Multi-color light curves of type Ia supernovae on the color-magnitude diagram: A novel step toward more precise distance and extinction estimates

    E-Print Network [OSTI]

    Wang, Lifan; Goldhaber, Gerson; Aldering, Greg; Perlmutter, Saul

    2003-01-01

    Date is earlier than for supernovae with smaller ?m 15 . SeeLight Curves of Type Ia Supernovae on the Color-Magnituderelation of Type Ia supernovae after optical maximum can

  1. Transportation Solutions to Enhance Prosperity and the Quality of Life Southwest Region

    E-Print Network [OSTI]

    operations/management. Of all our students, Mr. Yi-Chang Chiu, a doctoral student at UT-Austin, was selectedTransportation Solutions to Enhance Prosperity and the Quality of Life enter Southwest Region to Enhance Prosperity and the Quality of Life Transportation Solutions to Enhance Prosperity and the Quality

  2. Phylogeny, diet, and habitat of an extinct ground sloth from Cuchillo Cura, Neuquen Province, southwest Argentina

    E-Print Network [OSTI]

    , southwest Argentina Michael Hofreiter,a Julio L. Betancourt,b, * Alicia Pelliza Sbriller,c Vera Markgraf Laboratorio de Microhistologia, INTA-EEA Bariloche, CC 277 (R8400AMC) Bariloche, Argentina d Vera Markgraf in southwestern Argentina (38.5° S). Phylogenetic analyses of the mitochondrial DNA show that the dung originated

  3. EVALUATION OF TIDAL INLETS CHANNEL MIGRATION AND MANAGEMENT PRACTICES IN SOUTHWEST FLORIDA

    E-Print Network [OSTI]

    US Army Corps of Engineers

    484 EVALUATION OF TIDAL INLETS CHANNEL MIGRATION AND MANAGEMENT PRACTICES IN SOUTHWEST FLORIDA are analyzed to understand common factors that contribute to channel migration for inlets with/without jetties depth sufficient for reliable navigation in critical shoaling areas. In addition, ebb shoals have been

  4. PacificSouthwestResearchStationPrograms Air Pollution and Global Change

    E-Print Network [OSTI]

    PacificSouthwestResearchStationPrograms Air Pollution and Global Change Impacts on Western Forest branch of the USDA Forest Service in the states of California and Hawaii and the U.S.-affiliat- ed economy in the world) and Hawaii (a strategic location in the Pacific Rim economies and tourism). We

  5. PacificSouthwestResearchStationPrograms Air Pollution and Global Change

    E-Print Network [OSTI]

    PacificSouthwestResearchStationPrograms Air Pollution and Global Change Impacts on Western Forest of the USDA Forest Service in the states of California and Hawaii and the U.S.-affiliat- ed Pacific Islands in the world) and Hawaii (a strategic location in the Pacific Rim economies and tourism). We develop

  6. Wood Products-Utilization Gen. Tech. Rep. PSW-100. Berkeley, CA. Pacific Southwest Forest and Range

    E-Print Network [OSTI]

    Wood Products-Utilization 231 #12;Gen. Tech. Rep. PSW-100. Berkeley, CA. Pacific Southwest Forest and Range Experiment Station, Forest Service, U.S. Department of Agriculture; 1987. Utilization products. California's native and exotic hardwoods offer a wide range of utilization opportunities

  7. Fire and Forest History in Mixed-Conifer Forests of Southwest Colorado

    E-Print Network [OSTI]

    Fire and Forest History in Mixed-Conifer Forests of Southwest Colorado Peter M. Brown, Rocky tree-ring data do we have to reconstruct fire & forest history? Fire scars: Cambial mortality caused Mountain Tree-Ring Research Rosalind Wu, San Juan National Forest Carissa Aoki, Colorado State University

  8. Indigenous Tweets, Visible Voices, and Technology Panel discussion at SouthbySouthwest

    E-Print Network [OSTI]

    Scannell, Kevin Patrick

    Indigenous Tweets, Visible Voices, and Technology Panel discussion at SouthbySouthwest March 9 and minority language speakers are writing blogs, they're tweeting, creating podcasts, youtube videos, etc. all in their native language. Let's see some examples! Here's a blog by my friend and collaborator

  9. Predicting the amount of hydrogen stripped by the SN explosion for SN 2002cx-like SNe Ia

    SciTech Connect (OSTI)

    Liu, Zheng-Wei; Chen, X. F.; Wang, B.; Han, Z. W. [Yunnan Observatories, Chinese Academy of Sciences, Kunming 650011 (China); Kromer, M. [Max-Planck-Institut für Astrophysik, Karl-Schwarzschild-Str. 1, D-85741 Garching (Germany); Fink, M.; Röpke, F. K. [Institut für Theoretische Physik und Astrophysik, Universität Würzburg, Am Hubland, D-97074 Würzburg (Germany); Pakmor, R., E-mail: zwliu@ynao.ac.cn [Heidelberger Institut für Theoretische Studien, Schloss-Wolfsbrunnenweg 35, D-69118 Heidelberg (Germany)

    2013-12-01

    The most favored progenitor scenarios for Type Ia supernovae (SNe Ia) involve the single-degenerate (SD) scenario and the double-degenerate scenario. The absence of stripped hydrogen (H) in the nebular spectra of SNe Ia challenges the SD progenitor models. Recently, it was shown that pure deflagration explosion models of Chandrasekhar-mass white dwarfs, ignited off-center, reproduce the characteristic observational features of 2002cx-like SNe Ia very well. In this work we predict, for the first time, the amount of stripped H for the off-center, pure deflagration explosions. We find that their low kinetic energies lead to inefficient H mass stripping (? 0.01 M {sub ?}), indicating that the stripped H may be hidden in (observed) late-time spectra of SN 2002cx-like SNe Ia.

  10. Midwest Forensics Resource Center

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

    Chromatography-Mass Spectrometry and Liquid Chromatography-Mass Spectrometry for Discrimination of Salvia divinorum from Related Salvia Species Using Chemometric...

  11. Midwest Numerical Analysis Day

    E-Print Network [OSTI]

    Department of Mathematics, University of Nebraska, Omaha; Amlan Barua, Department of Applied Mathematics, Illinois Institute of Technology; Gregery Buzzard, ...

  12. Midwest Building Energy Program

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Delicious RankADVANCED MANUFACTURING OFFICESpecialAPPENDIX F Wetlands Assessment JulyDepartment ofRebateB O N N E V I

  13. Midwest Energy Codes Project

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Delicious RankADVANCED MANUFACTURING OFFICESpecialAPPENDIX F Wetlands Assessment JulyDepartment ofRebateB O N N E V

  14. Type-Ia supernova rates to redshift 2.4 from clash: The cluster lensing and supernova survey with Hubble

    SciTech Connect (OSTI)

    Graur, O.; Rodney, S. A.; Riess, A. G.; Medezinski, E. [Department of Physics and Astronomy, The Johns Hopkins University, Baltimore, MD 21218 (United States); Maoz, D. [School of Physics and Astronomy, Tel-Aviv University, Tel-Aviv 69978 (Israel); Jha, S. W.; Holoien, T. W.-S.; McCully, C.; Patel, B. [Department of Physics and Astronomy, Rutgers, The State University of New Jersey, Piscataway, NJ 08854 (United States); Postman, M.; Dahlen, T.; Strolger, L.-G.; Coe, D.; Bradley, L.; Koekemoer, A. [Space Telescope Science Institute, Baltimore, MD 21218 (United States); Benítez, N.; Molino, A. [Instituto de Astrofísica de Andalucía (CSIC), E-18080 Granada (Spain); Jouvel, S. [Institut de Ciencies de l'Espai, (IEEC-CSIC), E-08193 Bellaterra (Barcelona) (Spain); Nonino, M.; Balestra, I., E-mail: orgraur@jhu.edu [INAF-Osservatorio Astronomico di Trieste, I-34143 Trieste (Italy); and others

    2014-03-01

    We present the supernova (SN) sample and Type-Ia SN (SN Ia) rates from the Cluster Lensing And Supernova survey with Hubble (CLASH). Using the Advanced Camera for Surveys and the Wide Field Camera 3 on the Hubble Space Telescope (HST), we have imaged 25 galaxy-cluster fields and parallel fields of non-cluster galaxies. We report a sample of 27 SNe discovered in the parallel fields. Of these SNe, ?13 are classified as SN Ia candidates, including four SN Ia candidates at redshifts z > 1.2. We measure volumetric SN Ia rates to redshift 1.8 and add the first upper limit on the SN Ia rate in the range 1.8 < z < 2.4. The results are consistent with the rates measured by the HST/GOODS and Subaru Deep Field SN surveys. We model these results together with previous measurements at z < 1 from the literature. The best-fitting SN Ia delay-time distribution (DTD; the distribution of times that elapse between a short burst of star formation and subsequent SN Ia explosions) is a power law with an index of ?1.00{sub ?0.06(0.10)}{sup +0.06(0.09)} (statistical){sub ?0.08}{sup +0.12} (systematic), where the statistical uncertainty is a result of the 68% and 95% (in parentheses) statistical uncertainties reported for the various SN Ia rates (from this work and from the literature), and the systematic uncertainty reflects the range of possible cosmic star-formation histories. We also test DTD models produced by an assortment of published binary population synthesis (BPS) simulations. The shapes of all BPS double-degenerate DTDs are consistent with the volumetric SN Ia measurements, when the DTD models are scaled up by factors of 3-9. In contrast, all BPS single-degenerate DTDs are ruled out by the measurements at >99% significance level.

  15. Cosmology with Photometrically-Classified Type Ia Supernovae from the SDSS-II Supernova Survey

    E-Print Network [OSTI]

    Campbell, Heather; Nichol, Robert C; Sako, Masao; Smith, Mathew; Lampeitl, Hubert; Olmstead, Matthew D; Bassett, Bruce; Biswas, Rahul; Brown, Peter; Cinabro, David; Dawson, Kyle S; Dilday, Ben; Foley, Ryan J; Frieman, Joshua A; Garnavich, Peter; Hlozek, Renee; Jha, Saurabh W; Kuhlmann, Steve; Kunz, Martin; Marriner, John; Miquel, Ramon; Richmond, Michael; Riess, Adam; Schneider, Donald P; Sollerman, Jesper; Taylor, Matt; Zhao, Gong-Bo

    2012-01-01

    We present the cosmological analysis of 752 photometrically-classified Type Ia Supernovae (SNe Ia) obtained from the full Sloan Digital Sky Survey II (SDSS-II) Supernova (SN) Survey, supplemented with host-galaxy spectroscopy from the SDSS-III Baryon Oscillation Spectroscopic Survey (BOSS). Our photometric-classification method is based on the SN typing technique of Sako et al. (2011), aided by host galaxy redshifts (0.05Ia typing efficiency of 70.8%, with only 3.9% contamination from core-collapse (non-Ia) SNe. We demonstrate that this level of contamination has no effect on our cosmological constraints. We quantify and correct for our selection effects (e.g., Malmquist bias) using simulations. When fitting to a flat LambdaCDM cosmological model, we find that our photometric sample alone gives omega_m=0.24+0.07-0.05 (statistical errors only). If we relax the constraint on flatness, then our sample provides competitive joint stati...

  16. Easter Term 2015 Examination Timetables (from 6 April 15 May Exams) Architecture Tripos Part IA

    E-Print Network [OSTI]

    Easter Term 2015 Examination Timetables (from 6 April ­ 15 May Exams) Contents Architecture Tripos Part IA Architecture Tripos Part IB Architecture Tripos Part II Chemical Engineering Tripos Part IIA of Philosophy Examination in Technology Policy for the degree of Master of Philosophy Examination in Theology

  17. LOW MACH NUMBER MODELING OF TYPE Ia SUPERNOVAE. I. HYDRODYNAMICS A. S. Almgren,1

    E-Print Network [OSTI]

    Bell, John B.

    LOW MACH NUMBER MODELING OF TYPE Ia SUPERNOVAE. I. HYDRODYNAMICS A. S. Almgren,1 J. B. Bell,1 C. A. Rendleman,1 and M. Zingale2 Received 2005 August 5; accepted 2005 September 29 ABSTRACT We introduce a low is derived from the fully compressible equations using low Mach number asymptotics, but without any

  18. Type Ia supernovae in a hierarchical galaxy formation model: the Milky Way

    E-Print Network [OSTI]

    Masahiro Nagashima; Takashi Okamoto

    2006-02-03

    We investigate chemical evolution in Milky Way-like galaxies based on the cold dark matter model in which cosmic structures form via hierarchical merging. We introduce chemical enrichment due to type Ia supernovae (SNe Ia) into the Mitaka semi-analytic galaxy formation model developed by Nagashima & Yoshii. For the first time we derive distributions of stellar metallicities and their ratios in Milky Way-like galaxies treating chemical enrichment due to SNe Ia in a hierarchical galaxy formation model self-consistently. As a first attempt, we assume all SNe Ia to have the same lifetime, and assume instantaneous recycling for type II supernovae (SNe II). We find that our model reproduces well the metal abundance ratio [O/Fe] against [Fe/H] and the {iron metallicity distribution function} in the solar neighborhood. This means that the so-called G-dwarf problem is resolved by the hierarchical formation of galaxies, and a gas infall term introduced in traditional monolithic collapse models to solve this problem is well explained by the mixture of some physical processes such as hierarchical merging of dark halos, gas cooling, energy feedback and injection of gas and metals into hot gas due to supernovae. Our model predicts more oxygen-enhanced stars in bulges at [Fe/H] $\\simeq 0$ than in disks. This trend seems to be supported by recent observations while they have still uncertainties. More data in number and accuracy will provide independent and important constraints on galaxy formation. (abridged)

  19. I-A Modulated Digitally Controlled Non-Inverting Buck-Boost Converter for

    E-Print Network [OSTI]

    I-A Modulated Digitally Controlled Non-Inverting Buck-Boost Converter for WCDMA RF Power Amplifiers.edu Abstract- This paper focuses on the non-inverting buck- boost converter supplying an adjustable DC voltage the WCDMA RFPA settling time requirements. 1. INTRODUCTION Non-inverting buck-boost DC-DC power converter

  20. Properties and alignment of interstellar dust grains toward Type Ia Supernovae with anomalous polarization curves

    E-Print Network [OSTI]

    Hoang, Thiem

    2015-01-01

    Recent photometric and polarimetric observations of type Ia supernovae (SNe Ia) show unusually low total-to-selective extinction ratio ($R_{V}<2$) and wavelength of maximum polarization ($\\lambda_{max}<0.4\\mu m$) for several SNe Ia, which indicates peculiar properties of interstellar (IS) dust in the SN hosted galaxies and/or the presence of circumstellar (CS) dust. In this paper, we use inversion technique to infer best-fit grain size distribution and alignment function of interstellar grains along the lines of sight toward four SNe Ia with anomalous extinction and polarization data (SNe 1986G, 2006X, 2008fp, and 2014J). We find that to reproduce low values of $R_{V}$, a significant enhancement in the mass of small grains of radius $a< 0.1\\mu m$ is required. For SN 2014J, a simultaneous fit to observed extinction and polarization data is unsuccessful if the entire data is attributed to IS dust (model 1), but a good fit is obtained when accounting for the contribution of CS dust (model 2). For SN 200...

  1. Type Ia supernovae observations support the hypothesis of a static universe

    E-Print Network [OSTI]

    David F. Crawford

    2015-09-24

    This paper considers the hypothesis that the universe is static and demonstrates that type Ia supernova observations which appear to provide strong support for time dilation (and thus for an expanding universe) are in agreement with a static universe. An important anomaly is discovered in the standard calibration method which is that the reference template light curves have widths that are proportional to the rest-frame wavelength. The implication is that the observed light-curve widths do not show time dilation. Thus the time-dilation corrections are unwarranted and the universe is static. An important consideration is the Phillips relation, a correlation between the peak luminosity and the width of type Ia supernovae. Using the Phillips relation the analysis of a recent compilation of type Ia supernova observations is re-examined and it is shown that these observations are consistent with a static universe. It is also argued that the photometric redshift relation and spectroscopic ages are consistent with a static universe. As a separate but related issue it is shown that in the static model the density distribution of type Ia supernovae as a function of redshift agrees with the observations. All the evidence shows that the hypothesis of a static universe is supported.

  2. G-Mode Excitation During the Pre-explosive Simmering of Type Ia Supernovae

    E-Print Network [OSTI]

    Piro, Anthony L

    2011-01-01

    Prior to the explosive burning of a white dwarf (WD) that makes a Type Ia supernova (SN Ia), the star "simmers" for ~10^3 yrs in a convecting, carbon burning region. I estimate the excitation of g-modes by convection during this phase and explore their possible affect on the WD. As these modes propagate from the core of the WD toward its surface, their amplitudes grow with decreasing density. Once the modes reach nonlinear amplitudes, they break and deposit their energy into a shell of mass ~10^{-4}M_\\odot. This raises the surface temperature by 6*10^8 K, which is sufficient to ignite a layer of helium, as is expected to exist for some SN Ia scenarios. This predominantly synthesizes 28Si, 32S, 40Ca, and some 44Ti. These ashes are expanded out with the subsequent explosion up to velocities of ~20,000 km/s, which may explain the high velocity features (HVFs) seen in many SNe Ia. The appearance of HVFs would therefore be a useful discriminant for determining between progenitors, since a flammable helium-rich lay...

  3. Revealing progenitors of type Ia supernovae from their light curves and spectra

    E-Print Network [OSTI]

    Kutsuna, Masamichi

    2015-01-01

    In the single degenerate (SD) scenario of type Ia supernovae (SNe Ia), the collision of the ejecta with its companion results in stripping hydrogen rich matter from the companion star. This hydrogen rich matter might leave its trace in the light curves and/or spectra. In this paper, we perform radiation hydrodynamical simulations of this collision for three binary systems. As a result, we find that the emission from the shock-heated region is not as strong as in the previous study. This weak emission, however, may be a result of our underestimate of the coupling between the gas and radiation in the shock interaction. Therefore, though our results suggest that the observed early light curves of SNe Ia can not rule out binary systems with a short separation as the progenitor system, more elaborate numerical studies will be needed to reach a fair conclusion. Alternatively, our results indicate that the feature observed in the early phase of a recent type Ia SN 2014J might result from interaction of the ejecta wi...

  4. IAS 3353 001 Modern Brazil Instructor: Dr. Erika Robb-Larkins

    E-Print Network [OSTI]

    Oklahoma, University of

    IAS 3353 001 Modern Brazil Instructor: Dr. Erika Robb-Larkins MW 3:00-4:15 p.m. Hester Hall, room an anthropological perspective. Beginning with a broad overview of Brazil's colonial history and emergence the course with an appreciation of the complexities of Brazil today.... and with a desire to hop on the next

  5. HIGH-VELOCITY LINE FORMING REGIONS IN THE TYPE Ia SUPERNOVA 2009ig

    SciTech Connect (OSTI)

    Marion, G. H.; Foley, Ryan J.; Challis, Peter; Kirshner, Robert P. [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Vinko, Jozsef; Wheeler, J. Craig; Silverman, Jeffrey M. [University of Texas at Austin, 1 University Station C1400, Austin, TX 78712-0259 (United States); Hsiao, Eric Y. [Carnegie Observatories, Las Campanas Observatory, Colina El Pino, Casilla 601 (Chile); Brown, Peter J. [George P. and Cynthia Woods Mitchell Institute for Fundamental Physics and Astronomy, Department of Physics and Astronomy, Texas A and M University, 4242 AMU, College Station, TX 77843 (United States); Filippenko, Alexei V. [Department of Astronomy, University of California, Berkeley, CA 94720-3411 (United States); Garnavich, Peter [Department of Physics, University of Notre Dame, 225 Nieuwland Science Hall, Notre Dame, IN 46556 (United States); Landsman, Wayne B. [Adnet Systems, NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States); Parrent, Jerod T. [Las Cumbres Observatory Global Telescope Network, Goleta, CA 93117 (United States); Pritchard, Tyler A.; Roming, Peter W. A. [Department of Astronomy and Astrophysics, Penn State University, 525 Davey Lab, University Park, PA 16802 (United States); Wang, Xiaofeng, E-mail: gmarion@cfa.harvard.edu [Physics Department and Tsinghua Center for Astrophysics (THCA), Tsinghua University, Beijing 1,00084 (China)

    2013-11-01

    We report measurements and analysis of high-velocity (HVF) (>20,000 km s{sup –1}) and photospheric absorption features in a series of spectra of the Type Ia supernova (SN) 2009ig obtained between –14 days and +13 days with respect to the time of maximum B-band luminosity (B-max). We identify lines of Si II, Si III, S II, Ca II, and Fe II that produce both HVF and photospheric-velocity (PVF) absorption features. SN 2009ig is unusual for the large number of lines with detectable HVF in the spectra, but the light-curve parameters correspond to a slightly overluminous but unexceptional SN Ia (M{sub B} = –19.46 mag and ?m{sub 15}(B) = 0.90 mag). Similarly, the Si II ?6355 velocity at the time of B-max is greater than 'normal' for an SN Ia, but it is not extreme (v{sub Si} = 13,400 km s{sup –1}). The –14 days and –13 days spectra clearly resolve HVF from Si II ?6355 as separate absorptions from a detached line forming region. At these very early phases, detached HVF are prevalent in all lines. From –12 days to –6 days, HVF and PVF are detected simultaneously, and the two line forming regions maintain a constant separation of about 8000 km s{sup –1}. After –6 days all absorption features are PVF. The observations of SN 2009ig provide a complete picture of the transition from HVF to PVF. Most SNe Ia show evidence for HVF from multiple lines in spectra obtained before –10 days, and we compare the spectra of SN 2009ig to observations of other SNe. We show that each of the unusual line profiles for Si II ?6355 found in early-time spectra of SNe Ia correlate to a specific phase in a common development sequence from HVF to PVF.

  6. A Test for the Nature of the Type Ia Supernova Explosion Mechanism

    E-Print Network [OSTI]

    Philip A. Pinto; Ronald G. Eastman; Tamara Rogers

    2000-08-21

    Currently popular models for Type Ia supernovae (SNe Ia) fall into two general classes. The first comprises explosions of nearly pure carbon/oxygen (C/O) white dwarfs at the Chandrasekhar limit which ignite near their centers. The second consists of lower-mass C/O cores which are ignited by the detonation of an accreted surface helium layer. Explosions of the latter type produce copious Fe, Co and Ni K-alpha emission from 56Ni and 56Co decay in the detonated surface layers, emission which is much weaker from Chandrasekhar-mass models. The presence of this emission provides a simple and unambiguous discriminant between these two models for SNe Ia. Both mechanisms may produce 0.1-0.6 solar masses of 56Ni, making them bright gamma-ray line emitters. The time to maximum brightness of 56Ni decay lines is distinctly shorter in the sub-Chandrasekhar mass class of model (approximately 15 days) than in the Chandrasekhar mass model (approximately 30 days), making gamma-ray line evolution another direct test of the explosion mechanism. It should just be possible to detect K-shell emission from a sub-Chandrasekhar explosion from SNe Ia as far away as the Virgo cluster with the XMM Observatory. A 1 to 2 square meter X-ray telescope such as the proposed Con-X Observatory could observe K-alpha emission from sub-Chandrasekhar mass SNe Ia in the Virgo cluster, providing not just a detection, but high-accuracy flux and kinematic information.

  7. TYPE Ia SUPERNOVA COLORS AND EJECTA VELOCITIES: HIERARCHICAL BAYESIAN REGRESSION WITH NON-GAUSSIAN DISTRIBUTIONS

    SciTech Connect (OSTI)

    Mandel, Kaisey S.; Kirshner, Robert P. [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Foley, Ryan J., E-mail: kmandel@cfa.harvard.edu [Astronomy Department, University of Illinois at Urbana-Champaign, 1002 West Green Street, Urbana, IL 61801 (United States)

    2014-12-20

    We investigate the statistical dependence of the peak intrinsic colors of Type Ia supernovae (SNe Ia) on their expansion velocities at maximum light, measured from the Si II ?6355 spectral feature. We construct a new hierarchical Bayesian regression model, accounting for the random effects of intrinsic scatter, measurement error, and reddening by host galaxy dust, and implement a Gibbs sampler and deviance information criteria to estimate the correlation. The method is applied to the apparent colors from BVRI light curves and Si II velocity data for 79 nearby SNe Ia. The apparent color distributions of high-velocity (HV) and normal velocity (NV) supernovae exhibit significant discrepancies for B – V and B – R, but not other colors. Hence, they are likely due to intrinsic color differences originating in the B band, rather than dust reddening. The mean intrinsic B – V and B – R color differences between HV and NV groups are 0.06 ± 0.02 and 0.09 ± 0.02 mag, respectively. A linear model finds significant slopes of –0.021 ± 0.006 and –0.030 ± 0.009 mag (10{sup 3} km s{sup –1}){sup –1} for intrinsic B – V and B – R colors versus velocity, respectively. Because the ejecta velocity distribution is skewed toward high velocities, these effects imply non-Gaussian intrinsic color distributions with skewness up to +0.3. Accounting for the intrinsic-color-velocity correlation results in corrections to A{sub V} extinction estimates as large as –0.12 mag for HV SNe Ia and +0.06 mag for NV events. Velocity measurements from SN Ia spectra have the potential to diminish systematic errors from the confounding of intrinsic colors and dust reddening affecting supernova distances.

  8. Constraining Dark Energy and Cosmological Transition Redshift with Type Ia Supernovae

    E-Print Network [OSTI]

    F. Y. Wang; Z. G. Dai

    2007-08-30

    The property of dark energy and the physical reason for acceleration of the present universe are two of the most difficult problems in modern cosmology. The dark energy contributes about two-thirds of the critical density of the present universe from the observations of type-Ia supernova (SNe Ia) and anisotropy of cosmic microwave background (CMB).The SN Ia observations also suggest that the universe expanded from a deceleration to an acceleration phase at some redshift, implying the existence of a nearly uniform component of dark energy with negative pressure. We use the ``gold'' sample containing 157 SNe Ia and two recent well-measured additions, SNe Ia 1994ae and 1998aq to explore the properties of dark energy and the transition redshift. For a flat universe with the cosmological constant, we measure $\\Omega_{M}=0.28_{-0.05}^{+0.04}$, which is consistent with Riess et al. The transition redshift is $z_{T}=0.60_{-0.08}^{+0.06}$. We also discuss several dark energy models that define the $w(z)$ of the parameterized equation of state of dark energy including one parameter and two parameters ($w(z)$ being the ratio of the pressure to energy density). Our calculations show that the accurately calculated transition redshift varies from $z_{T}=0.29_{-0.06}^{+0.07}$ to $z_{T}=0.60_{-0.08}^{+0.06}$ across these models. We also calculate the minimum redshift $z_{c}$ at which the current observations need the universe to accelerate.

  9. Mass Market Demand Response and Variable Generation Integration Issues: A Scoping Study

    E-Print Network [OSTI]

    Cappers, Peter

    2012-01-01

    Goldman, G. (2009) Retail demand response in Southwest PowerCoordination of retail demand response with Midwest ISO2010. 110 pages. Demand Response and Variable Generation

  10. Type Ia supernova rate measurements to redshift 2.5 from CANDELS: Searching for prompt explosions in the early universe

    SciTech Connect (OSTI)

    Rodney, Steven A.; Riess, Adam G.; Graur, Or; Jones, David O. [Department of Physics and Astronomy, The Johns Hopkins University, Baltimore, MD 21218 (United States); Strolger, Louis-Gregory; Dahlen, Tomas; Casertano, Stefano; Ferguson, Henry C.; Koekemoer, Anton M. [Space Telescope Science Institute, Baltimore, MD 21218 (United States); Dickinson, Mark E. [National Optical Astronomy Observatory, 950 North Cherry Avenue, Tucson, AZ 85719 (United States); Garnavich, Peter [Department of Physics, University of Notre Dame, Notre Dame, IN 46556 (United States); Hayden, Brian [E.O. Lawrence Berkeley National Lab, 1 Cyclotron Road, Berkeley, CA 94720 (United States); Jha, Saurabh W.; McCully, Curtis; Patel, Brandon [Department of Physics and Astronomy, Rutgers, The State University of New Jersey, Piscataway, NJ 08854 (United States); Kirshner, Robert P. [Harvard-Smithsonian Center for Astrophysics, Cambridge, MA 02138 (United States); Mobasher, Bahram [Department of Physics and Astronomy, University of California, Riverside, CA 92521 (United States); Weiner, Benjamin J. [Department of Astronomy, University of Arizona, Tucson, AZ 85721 (United States); Cenko, S. Bradley [Astrophysics Science Division, NASA Goddard Space Flight Center, Mail Code 661, Greenbelt, MD 20771 (United States); Clubb, Kelsey I. [Department of Astronomy, University of California, Berkeley, CA 94720 (United States); and others

    2014-07-01

    The Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey (CANDELS) was a multi-cycle treasury program on the Hubble Space Telescope (HST) that surveyed a total area of ?0.25 deg{sup 2} with ?900 HST orbits spread across five fields over three years. Within these survey images we discovered 65 supernovae (SNe) of all types, out to z ? 2.5. We classify ?24 of these as Type Ia SNe (SNe Ia) based on host galaxy redshifts and SN photometry (supplemented by grism spectroscopy of six SNe). Here we present a measurement of the volumetric SN Ia rate as a function of redshift, reaching for the first time beyond z = 2 and putting new constraints on SN Ia progenitor models. Our highest redshift bin includes detections of SNe that exploded when the universe was only ?3 Gyr old and near the peak of the cosmic star formation history. This gives the CANDELS high redshift sample unique leverage for evaluating the fraction of SNe Ia that explode promptly after formation (<500 Myr). Combining the CANDELS rates with all available SN Ia rate measurements in the literature we find that this prompt SN Ia fraction is f{sub P} = 0.53{sub stat0.10}{sup ±0.09}{sub sys0.26}{sup ±0.10}, consistent with a delay time distribution that follows a simple t {sup –1} power law for all times t > 40 Myr. However, mild tension is apparent between ground-based low-z surveys and space-based high-z surveys. In both CANDELS and the sister HST program CLASH (Cluster Lensing And Supernova Survey with Hubble), we find a low rate of SNe Ia at z > 1. This could be a hint that prompt progenitors are in fact relatively rare, accounting for only 20% of all SN Ia explosions—though further analysis and larger samples will be needed to examine that suggestion.

  11. Effects of mineral aerosols on the summertime climate of southwest Asia: Incorporating subgrid variability in a dust emission scheme

    E-Print Network [OSTI]

    Marcella, Marc Pace

    [1] Improvements in modeling mineral aerosols over southwest Asia are made to the dust scheme in a regional climate model by representing subgrid variability of both wind speed and surface roughness length. The new module ...

  12. Application of in-situ cosmogenic nuclide analysis to landform evolution in Dartmoor, south-west Britain 

    E-Print Network [OSTI]

    Hägg, Joseph Hunter

    2009-01-01

    Located beyond the southern limit of glaciation in Britain, the upland granitic terrain of Dartmoor, south-west England, has been exposed to long intervals of intense periglacial activity during the Pleistocene. This ...

  13. Sweetspot: Near-infrared observations of 13 type Ia supernovae from a new NOAO survey probing the nearby smooth Hubble flow

    SciTech Connect (OSTI)

    Weyant, Anja; Wood-Vasey, W. Michael [Pittsburgh Particle physics, Astrophysics, and Cosmology Center (PITT PACC), Physics and Astronomy Department, University of Pittsburgh, Pittsburgh, PA 15260 (United States); Allen, Lori; Joyce, Richard; Matheson, Thomas [National Optical Astronomy Observatory, 950 North Cherry Avenue, Tucson, AZ 85719 (United States); Garnavich, Peter M. [Department of Physics, 225 Nieuwland Science Hall, Notre Dame, IN 46556 (United States); Jha, Saurabh W., E-mail: anw19@pitt.edu [Department of Physics and Astronomy, Rutgers, the State University of New Jersey, 136 Frelinghuysen Road, Piscataway, NJ 08854 (United States)

    2014-04-01

    We present 13 Type Ia supernovae (SNe Ia) observed in the rest-frame near-infrared (NIR) from 0.02 < z < 0.09 with the WIYN High-resolution Infrared Camera on the WIYN 3.5 m telescope. With only one to three points per light curve and a prior on the time of maximum from the spectrum used to type the object, we measure an H-band dispersion of spectroscopically normal SNe Ia of 0.164 mag. These observations continue to demonstrate the improved standard brightness of SNe Ia in an H band, even with limited data. Our sample includes two SNe Ia at z ? 0.09, which represent the most distant rest-frame NIR H-band observations published to date. This modest sample of 13 NIR SNe Ia represent the pilot sample for {sup S}weetSpot{sup —}a 3 yr NOAO Survey program that will observe 144 SNe Ia in the smooth Hubble flow. By the end of the survey we will have measured the relative distance to a redshift of z ? 0.05%-1%. Nearby Type Ia supernova (SN Ia) observations such as these will test the standard nature of SNe Ia in the rest-frame NIR, allow insight into the nature of dust, and provide a critical anchor for future cosmological SN Ia surveys at higher redshift.

  14. Reservoir Characterization of the Lower Green River Formation, Southwest Uinta Basin, Utah

    SciTech Connect (OSTI)

    Morgan, Craig D.; Chidsey, Jr., Thomas C.; McClure, Kevin P.; Bereskin, S. Robert; Deo, Milind D.

    2002-12-02

    The objectives of the study were to increase both primary and secondary hydrocarbon recovery through improved characterization (at the regional, unit, interwell, well, and microscopic scale) of fluvial-deltaic lacustrine reservoirs, thereby preventing premature abandonment of producing wells. The study will encourage exploration and establishment of additional water-flood units throughout the southwest region of the Uinta Basin, and other areas with production from fluvial-deltaic reservoirs.

  15. Mechanistic studies of proton-coupled electron transfer in aminotyrosine- and fluorotyrosine- substituted class Ia Ribonucleotide reductase

    E-Print Network [OSTI]

    Minnihan, Ellen Catherine

    2012-01-01

    Ribonucleotide reductase (RNR) catalyzes the conversion of nucleotides to 2'- deoxynucleotides in all organisms. The class Ia RNR from Escherichia coli is active as an a2p2 complex and utilizes an unprecedented mechanism ...

  16. Control of metallation and active cofactor assembly in the class Ia and Ib ribonucleotide reductases: diiron or dimanganese?

    E-Print Network [OSTI]

    Stubbe, JoAnne

    Ribonucleotide reductases (RNRs) convert nucleotides to deoxynucleotides in all organisms. Activity of the class Ia and Ib RNRs requires a stable tyrosyl radical (Y•), which can be generated by the reaction of O[subscript ...

  17. Restframe I-band Hubble diagram for type Ia supernovae up to redshift z ~; 0.5

    E-Print Network [OSTI]

    2005-01-01

    in STScI Symposium Ser. 13, Supernovae and gamma-ray bursts:Highlight: The Physics of Supernovae, ed. W. Hillebrandt &diagram for type Ia supernovae up to redshift z ? 0.5 ? S.

  18. Experto Universitario Java Enterprise Validacin e internacionalizacin 2012-2013 Depto. Ciencia de la Computacin e IA Spring

    E-Print Network [OSTI]

    Escolano, Francisco

    Experto Universitario Java Enterprise Validación e internacionalización © 2012-2013 Depto. Ciencia #12;Experto Universitario Java Enterprise Validación e internacionalización © 2012-2013 Depto. Ciencia Java Enterprise Validación e internacionalización © 2012-2013 Depto. Ciencia de la Computación e IA

  19. In vivo cofactor biosynthesis and maintenance in the class Ia ribonucleotide reductase small subunit of Escherichia coli

    E-Print Network [OSTI]

    Wu, Chia-Hung, Ph. D. Massachusetts Institute of Technology

    2009-01-01

    The small subunit ([beta]2) of Escherichia coli class Ia ribonucleotide reductases (RNRs) contains a diferric tyrosyl radical (Y*) cofactor essential for the conversion of nucleotides to deoxynucleotides that are needed ...

  20. Constraining spacetime variations of nuclear decay rates from light curves of type Ia supernovae

    E-Print Network [OSTI]

    Ivan Karpikov; Maxim Piskunov; Anton Sokolov; Sergey Troitsky

    2015-05-12

    The luminosity of fading type Ia supernovae is governed by radioactive decays of 56Ni and 56Co. The decay rates are proportional to the Fermi coupling constant G_F and, therefore, are determined by the vacuum expectation value v of the Brout-Englert-Higgs field. We use publicly available sets of light curves of type Ia supernova at various redshifts to constrain possible spacetime variations of the 56Ni decay rate. The resulting constraint is not very tight; however, it is the only direct bound on the variation of the decay rate for redshifts up to z~1. We discuss potential applications of the result to searches for non-constancy of G_F and v.

  1. SNe Ia tests of quintessence tracker cosmology in an anisotropic background

    SciTech Connect (OSTI)

    Miranda, W. [Instituto Federal da Bahia, Paulo Afonso, Bahia (Brazil); Carneiro, S.; Pigozzo, C., E-mail: welber.miranda@ifba.edu.br, E-mail: saulo.carneiro@pq.cnpq.br, E-mail: cpigozzo@ufba.br [Instituto de Física, Universidade Federal da Bahia, Salvador, Bahia (Brazil)

    2014-07-01

    We investigate the observational effects of a quintessence model in an anisotropic spacetime. The anisotropic metric is a non-rotating particular case of a generalized Gödel's metric and is classified as Bianchi III. This metric is an exact solution of the Einstein-Klein-Gordon field equations with an anisotropic scalar field ?, which is responsible for the anisotropy of the spacetime geometry. We test the model against observations of type Ia supernovae, analyzing the SDSS dataset calibrated with the MLCS2k2 fitter, and the results are compared to standard quintessence models with Ratra-Peebles potentials. We obtain a good agreement with observations, with best values for the matter and curvature density parameters ?{sub M} = 0.29 and ?{sub k}= 0.01 respectively. We conclude that present SNe Ia observations cannot, alone, distinguish a possible anisotropic axis in the cosmos.

  2. On the Brightness of Surviving Companions in Type Ia Supernova Remnants

    E-Print Network [OSTI]

    Noda, Kazuhiro; Shigeyama, Toshikazu

    2015-01-01

    The progenitor systems for type Ia supernovae are still controversial. One of the methods to test the proposed scenario for the progenitor systems is to identify companions that are supposed to survive according to the so-called single degenerate scenario. These companions might be affected by supernova ejecta. We present several numerical simulations of surviving red-giant companions whose envelopes were stripped and heated. We find that red-giants with less-massive helium cores ($\\lesssim0.30\\,M_{\\odot}$) can be so faint after the supernovae that we cannot detect them. In addition, we apply the results to the case of SNR 0509-67.5, and put constraints on the helium core mass, envelope stripping, and energy injection under the single degenerate scenario for type Ia supernovae.

  3. On the small-scale stability of thermonuclear flames in Type Ia supernovae

    E-Print Network [OSTI]

    F. K. Roepke; J. C. Niemeyer; W. Hillebrandt

    2003-05-02

    We present a numerical model which allows us to investigate thermonuclear flames in Type Ia supernova explosions. The model is based on a finite-volume explicit hydrodynamics solver employing PPM. Using the level-set technique combined with in-cell reconstruction and flux-splitting schemes we are able to describe the flame in the discontinuity approximation. We apply our implementation to flame propagation in Chandrasekhar-mass Type Ia supernova models. In particular we concentrate on intermediate scales between the flame width and the Gibson-scale, where the burning front is subject to the Landau-Darrieus instability. We are able to reproduce the theoretical prediction on the growth rates of perturbations in the linear regime and observe the stabilization of the flame in a cellular shape. The increase of the mean burning velocity due to the enlarged flame surface is measured. Results of our simulation are in agreement with semianalytical studies.

  4. Comparing the host galaxies of type Ia, type II, and type Ibc supernovae

    SciTech Connect (OSTI)

    Shao, X.; Liang, Y. C.; Chen, X. Y.; Zhong, G. H.; Deng, L. C.; Zhang, B.; Shi, W. B.; Zhou, L. [Key Laboratory of Optical Astronomy, National Astronomical Observatories, Chinese Academy of Sciences, 20A Datun Road, Chaoyang District, Beijing 100012 (China); Dennefeld, M. [Institut d'Astrophysique de Paris, CNRS, and Universite P. et M. Curie, 98bis Bd Arago, F-75014 Paris (France); Hammer, F.; Flores, H., E-mail: xshao@bao.ac.cn, E-mail: ycliang@bao.ac.cn [GEPI, Observatoire de Paris-Meudon, F-92195 Meudon (France)

    2014-08-10

    We compare the host galaxies of 902 supernovae (SNe), including SNe Ia, SNe II, and SNe Ibc, which are selected by cross-matching the Asiago Supernova Catalog with the Sloan Digital Sky Survey (SDSS) Data Release 7. We selected an additional 213 galaxies by requiring the light fraction of spectral observations to be >15%, which could represent well the global properties of the galaxies. Among these 213 galaxies, 135 appear on the Baldwin-Phillips-Terlevich diagram, which allows us to compare the hosts in terms of whether they are star-forming (SF) galaxies, active galactic nuclei (AGNs; including composites, LINERs, and Seyfert 2s) or absorption-line galaxies (Absorps; i.e., their related emission lines are weak or non-existent). The diagrams related to the parameters D{sub n}(4000), H?{sub A}, stellar masses, star formation rates (SFRs), and specific SFRs for the SNe hosts show that almost all SNe II and most of the SNe Ibc occur in SF galaxies, which have a wide range of stellar masses and low D{sub n}(4000). The SNe Ia hosts as SF galaxies following similar trends. A significant fraction of SNe Ia occurs in AGNs and absorption-line galaxies, which are massive and have high D{sub n}(4000). The stellar population analysis from spectral synthesis fitting shows that the hosts of SNe II have a younger stellar population than hosts of SNe Ia. These results are compared with those of the 689 comparison galaxies where the SDSS fiber captures less than 15% of the total light. These comparison galaxies appear biased toward higher 12+log(O/H) (?0.1 dex) at a given stellar mass. Therefore, we believe the aperture effect should be kept in mind when the properties of the hosts for different types of SNe are discussed.

  5. Photometric selection of Type Ia supernovae in the Supernova Legacy Survey

    E-Print Network [OSTI]

    Bazin, G; Palanque-Delabrouille, N; Rich, J; Aubourg, E; Astier, P; Balland, C; Basa, S; Carlberg, R G; Conley, A; Fouchez, D; Guy, J; Hardin, D; Hook, I M; Howell, D A; Pain, R; Perrett, K; Pritchet, C J; Regnault, N; Sullivan, M; Fourmanoit, N; Gonzalez-Gaitan, S; Lidman, C; Perlmutter, S; Ripoche, P; Walker, E S

    2011-01-01

    We present a sample of 485 photometrically identified Type Ia supernova candidates mined from the first three years of data of the CFHT SuperNova Legacy Survey (SNLS). The images were submitted to a deferred processing independent of the SNLS real-time detection pipeline. Light curves of all transient events were reconstructed in the g_M, r_M, i_M and z_M filters and submitted to automated sequential cuts in order to identify possible supernovae. Pure noise and long-term variable events were rejected by light curve shape criteria. Type Ia supernova identification relied on event characteristics fitted to their light curves assuming the events to be normal SNe Ia. The light curve fitter SALT2 was used for this purpose, assigning host galaxy photometric redshifts to the tested events. The selected sample of 485 candidates is one magnitude deeper than that allowed by the SNLS spectroscopic identification. The contamination by supernovae of other types is estimated to be 4%. Testing Hubble diagram residuals with ...

  6. The Peculiar SN 2005hk: Do Some Type Ia Supernovae Explode as Deflagrations?

    E-Print Network [OSTI]

    Phillips, M M; Frieman, J A; Blinnikov, S I; De Poy, D L; Prieto, J L; Milne, P; Contreras, C; Folatelli, G; Morrell, N; Hamuy, M; Suntzeff, N B; Roth, M; González, S; Krzeminski, W; Filippenko, A V; Freedman, W L; Chornock, R; Jha, S; Madore, B F; Persson, S E; Burns, C R; Wyatt, P; Murphy, D; Foley, R J; Ganeshalingam, M; Serduke, F J D; Krisciunas, K; Bassett, B; Becker, A; Dilday, B; Eastman, J; Garnavich, P M; Holtzman, J; Kessler, R; Lampeitl, H; Marriner, J P; Frank, S; Marshall, J L; Miknaitis, G; Sako, M; Schneider, D P; Van der Heyden, K J; Yasuda, N; Yasuda, Naoki

    2006-01-01

    We present extensive u'g'r'i'BVRIYJHKs photometry and optical spectroscopy of SN 2005hk. These data reveal that SN 2005hk was nearly identical in its observed properties to SN 2002cx, which has been called ``the most peculiar known type Ia supernova.'' Both supernovae exhibited high ionization SN 1991T-like pre-maximum spectra, yet low peak luminosities like SN 1991bg. The spectra reveal that SN 2005hk, like SN 2002cx, exhibited expansion velocities that were roughly half those of typical type Ia supernovae. The R and I light curves of both supernovae were also peculiar in not displaying the secondary maximum observed for normal type Ia supernovae. Our YJH photometry of SN 2005hk reveals the same peculiarity in the near-infrared. By combining our optical and near-infrared photometry of SN 2005hk with published ultraviolet light curves obtained with the Swift satellite, we are able to construct a bolometric light curve from ~10 days before to ~60 days after B maximum. The shape and unusually low peak luminosit...

  7. The Peculiar SN 2005hk: Do Some Type Ia Supernovae Explode as Deflagrations?

    E-Print Network [OSTI]

    M. M. Phillips; W. Li; J. A. Frieman; S. I. Blinnikov; D. DePoy; J. L. Prieto; P. Milne; C. Contreras; G. Folatelli; N. Morrell; M. Hamuy; N. B. Suntzeff; M. Roth; S. Gonzalez; W. Krzeminski; A. V. Filippenko; W. L. Freedman; R. Chornock; S. Jha; B. F. Madore; S. E. Persson; C. R. Burns; P. Wyatt; D. Murphy; R. J. Foley; M. Ganeshalingam; F. J. D. Serduke; K. Krisciunas; B. Bassett; A. Becker; B. Dilday; J. Eastman; P. M. Garnavich; J. Holtzman; R. Kessler; H. Lampeitl; J. Marriner; S. Frank; J. L. Marshall; G. Miknaitis; M. Sako; D. P. Schneider; K. van der Heyden; Naoki Yasuda

    2007-03-26

    We present extensive u'g'r'i'BVRIYJHKs photometry and optical spectroscopy of SN 2005hk. These data reveal that SN 2005hk was nearly identical in its observed properties to SN 2002cx, which has been called ``the most peculiar known type Ia supernova.'' Both supernovae exhibited high ionization SN 1991T-like pre-maximum spectra, yet low peak luminosities like SN 1991bg. The spectra reveal that SN 2005hk, like SN 2002cx, exhibited expansion velocities that were roughly half those of typical type Ia supernovae. The R and I light curves of both supernovae were also peculiar in not displaying the secondary maximum observed for normal type Ia supernovae. Our YJH photometry of SN 2005hk reveals the same peculiarity in the near-infrared. By combining our optical and near-infrared photometry of SN 2005hk with published ultraviolet light curves obtained with the Swift satellite, we are able to construct a bolometric light curve from ~10 days before to ~60 days after B maximum. The shape and unusually low peak luminosity of this light curve, plus the low expansion velocities and absence of a secondary maximum at red and near-infrared wavelengths, are all in reasonable agreement with model calculations of a 3D deflagration which produces ~0.25 M_sun of 56Ni.

  8. On type IIn/Ia-CSM supernovae as exemplified by SN 2012ca

    E-Print Network [OSTI]

    Inserra, C; Smartt, S J; Benetti, S; Chen, T -W; Childress, M; Gal-Yam, A; Howell, D A; Kangas, T; Pignata, G; Polshaw, J; Sullivan, M; Smith, K W; Valenti, S; Young, D R; Parker, S; Seccull, T; McCrum, M

    2015-01-01

    We present the complete set of ultra-violet, optical and near-infrared photometry and spectroscopy for SN 2012ca, covering the period from 6 days prior to maximum light, until 531 days after maximum. The spectroscopic time series for SN 2012ca is essentially unchanged over 1.5 years, and appear to be dominated at all epochs by signatures of interaction with a dense circumstellar medium rather than the underlying supernova (SN). SN 2012ca is a member of the class of type Ia-CSM/IIn SNe, the nature of which have been debated extensively in the literature. The two leading scenarios are either a type Ia SN exploding within a dense CSM from a non-degenerate, evolved companion, or a core-collapse SN from a massive star. While some members of the class have been unequivocally associated with type Ia SNe, in other cases the association is less certain. While it is possible that Sn 2012ca does arise from a thermonuclear SN, this would require a relatively high (between 20 and 70 per cent) efficiency in converting kine...

  9. Observational constraints from SNe Ia and Gamma-Ray Bursts on a clumpy universe

    E-Print Network [OSTI]

    Nora Bretón; Ariadna Montiel

    2013-03-06

    The luminosity distance describing the effect of local inhomogeneities in the propagation of light proposed by Zeldovich-Kantowski-Dyer-Roeder (ZKDR) is tested with two probes for two distinct ranges of redshifts: supernovae Ia (SNe Ia) in 0.015 gamma-ray bursts (GRBs) in 1.547 < z < 3.57. Our analysis is performed by a Markov Chain Monte Carlo (MCMC) code that allows us to constrain the matter density parameter \\Omega_m as well as the smoothness parameter $\\alpha$ that measures the inhomogeneous-homogeneous rate of the cosmic fluid in a flat \\LambdaCDM model. The obtained best fits are (\\Omega_m=0.285^{+0.019}_{-0.018}, \\alpha= 0.856^{+0.106}_{-0.176}) from SNe Ia and (\\Omega_m=0.259^{+0.028}_{-0.028}, \\alpha=0.587^{+0.201}_{-0.202}) from GRBs, while from the joint analysis the best fits are (\\Omega_m=0.284^{+0.021}_{-0.020}, \\alpha= 0.685^{+0.164}_{-0.171}) with a \\chi^2_{\\rm red}=0.975. The value of the smoothness parameter $\\alpha$ indicates a clumped universe however it does not have an impact on the amount of dark energy (cosmological constant) needed to fit observations. This result may be an indication that the Dyer-Roeder approximation does not describe in a precise form the effects of clumpiness in the expansion of the universe.

  10. Convection during the Late Stages of Simmering in Type Ia Supernovae

    E-Print Network [OSTI]

    Anthony L. Piro; Philip Chang

    2008-01-08

    Following unstable ignition of carbon, but prior to explosion, a white dwarf (WD) in a Type Ia supernova (SN Ia) undergoes a simmering phase. During this time, a central convective region grows and encompasses ~1 Msun of the WD over a timescale of ~1000 yrs, which sets the thermal and turbulent profile for the subsequent explosion. We study this time-dependent convection and summarize some of the key features that differ from the traditional, steady-state case. We show that the long conductive timescale above the convective zone and the extraction of energy to heat the WD core leads to a decrease of the convective luminosity and characteristic velocities near the convective zone's top boundary. In addition, differences in the composition between the convective core and the conductive exterior will significantly alter the location of this boundary. In this respect, we find the biggest effect due to complete 22Ne sedimentation prior to carbon ignition. These effects add diversity to the possible WD models, which may alter the properties of the SN Ia explosion.

  11. Probing the isotropy of cosmic acceleration traced by Type Ia supernovae

    E-Print Network [OSTI]

    Javanmardi, Behnam; Kroupa, Pavel; Pflamm-Altenburg, Jan

    2015-01-01

    We present a method to test the isotropy of the magnitude-redshift relation of Type Ia Supernovae (SNe Ia) and single out the most discrepant direction (in terms of the signal-to-noise ratio) with respect to the all-sky data. Our technique accounts for possible directional variations of the corrections for SNe Ia and yields all-sky maps of the best-fit cosmological parameters with arbitrary angular resolution. To show its potential, we apply our method to the recent Union2.1 compilation, building maps with three different angular resolutions. We use a Monte Carlo method to estimate the statistical significance with which we could reject the null hypothesis that the magnitude-redshift relation is isotropic based on the properties of the observed most discrepant directions. We find that, based on pure signal-to-noise arguments, the null hypothesis cannot be rejected at any meaningful confidence level. However, if we also consider that the strongest deviations in the Union2.1 sample closely align with the dipole...

  12. Optical and ultraviolet observations of the narrow-lined type Ia SN 2012fr in NGC 1365

    SciTech Connect (OSTI)

    Zhang, Ju-Jia; Bai, Jin-Ming; Wang, Bo; Liu, Zheng-Wei [Yunnan Observatories (YNAO), Chinese Academy of Sciences, Kunming 650011 (China); Wang, Xiao-Feng; Zhao, Xu-Lin; Chen, Jun-Cheng [Physics Department and Tsinghua Center for Astrophysics (THCA), Tsinghua University, Beijing 100084 (China); Zhang, Tian-Meng, E-mail: jujia@ynao.ac.cn, E-mail: baijinming@ynao.ac.cn, E-mail: wang_xf@mail.tsinghua.edu.cn [National Astronomical Observatories of China (NAOC), Chinese Academy of Sciences, Beijing 100012 (China)

    2014-07-01

    Extensive optical and ultraviolet (UV) observations of the type Ia supernova (SN Ia) 2012fr are presented in this paper. It has a relatively high luminosity, with an absolute B-band peak magnitude of about –19.5 mag and a smaller post-maximum decline rate than normal SNe Ia (e.g., ?m {sub 15}(B) =0.85 ± 0.05 mag). Based on the UV and optical light curves, we derived that a {sup 56}Ni mass of about 0.88 M {sub ?} was synthesized in the explosion. The earlier spectra are characterized by noticeable high-velocity features of Si II ?6355 and Ca II with velocities in the range of ?22, 000-25, 000 km s{sup –1}. At around the maximum light, these spectral features are dominated by the photospheric components which are noticeably narrower than normal SNe Ia. The post-maximum velocity of the photosphere remains almost constant at ?12,000 km s{sup –1} for about one month, reminiscent of the behavior of some luminous SNe Ia like SN 1991T. We propose that SN 2012fr may represent a subset of the SN 1991T-like SNe Ia viewed in a direction with a clumpy or shell-like structure of ejecta, in terms of a significant level of polarization reported in Maund et al. in 2013.

  13. The Silicon and Calcium High-Velocity Features in Type Ia Supernovae from Early to Maximum Phases

    E-Print Network [OSTI]

    Zhao, Xulin; Maeda, Keiichi; Sai, Hanna; Zhang, Tianmeng; Zhang, Jujia; Huang, Fang; Rui, Liming; Zhou, Qi; Mo, Jun

    2015-01-01

    The high-velocity features (HVFs) in optical spectra of type Ia supernovae (SNe Ia) are examined with a large sample including very early-time spectra (e.g., t < -7 days). Multiple Gaussian fits are applied to examine the HVFs and their evolutions, using constraints on expansion velocities for the same species (i.e., SiII 5972 and SiII 6355). We find that strong HVFs tend to appear in SNe Ia with smaller decline rates (e.g., dm15(B)<1.4 mag), clarifying that the finding by Childress et al. (2014) for the Ca-HVFs in near-maximum-light spectra applies both to the Si-HVFs and Ca-HVFs in the earlier phase. The Si-HVFs seem to be more common in fast-expanding SNe Ia, which is different from the earlier result that the Ca-HVFs are associated with SNe Ia having slower SiII 6355 velocities at maximum light (i.e., Vsi). This difference can be due to that the HVFs in fast-expanding SNe Ia usually disappear more rapidly and are easily blended with the photospheric components when approaching the maximum light. Mor...

  14. A high-resolution X-ray and optical study of SN 1006: asymmetric expansion and small-scale structure in a type IA supernova remnant

    SciTech Connect (OSTI)

    Winkler, P. Frank [Department of Physics, Middlebury College, Middlebury, VT 05753 (United States); Williams, Brian J.; Petre, Robert; Hwang, Una [NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States); Reynolds, Stephen P. [Physics Department, North Carolina State University, Raleigh, NC 27695 (United States); Long, Knox S. [Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218 (United States); Katsuda, Satoru, E-mail: winkler@middlebury.edu, E-mail: brian.j.williams@nasa.gov, E-mail: robert.petre-1@nasa.gov, E-mail: reynolds@ncsu.edu, E-mail: long@stsci.edu [RIKEN (The Institute of Physical and Chemical Research), 2-1 Hirosawa, Wako, Saitama 351-0198 (Japan)

    2014-02-01

    We introduce a deep (670 ks) X-ray survey of the entire SN 1006 remnant from the Chandra X-Ray Observatory, together with a deep H? image of SN 1006 from the 4 m Blanco telescope at CTIO. Comparison with Chandra images from 2003 gives the first measurement of the X-ray proper motions around the entire periphery, carried out over a 9 yr baseline. We find that the expansion velocity varies significantly with azimuth. The highest velocity of ?7400 km s{sup –1} (almost 2.5 times that in the northwest (NW)) is found along the southeast (SE) periphery, where both the kinematics and the spectra indicate that most of the X-ray emission stems from ejecta that have been decelerated little, if at all. Asymmetries in the distribution of ejecta are seen on a variety of spatial scales. Si-rich ejecta are especially prominent in the SE quadrant, while O and Mg are more uniformly distributed, indicating large-scale asymmetries arising from the explosion itself. Neon emission is strongest in a sharp filament just behind the primary shock along the NW rim, where the pre-shock density is highest. Here the Ne is likely interstellar, while Ne within the shell may include a contribution from ejecta. Within the interior of the projected shell we find a few isolated 'bullets' of what appear to be supernova ejecta that are immediately preceded by bowshocks seen in H?, features that we interpret as ejecta knots that have reached relatively dense regions of the surrounding interstellar medium, but that appear in the interior in projection. Recent three-dimensional hydrodynamic models for Type Ia supernovae display small-scale features that strongly resemble the ones seen in X-rays in SN 1006; an origin in the explosion itself or from subsequent hydrodynamic instabilities both remain viable options. We have expanded the search for precursor X-ray emission ahead of a synchrotron-dominated shock front, as expected from diffusive shock acceleration theory, to numerous regions along both the northeast and southwest rims of the shell. Our data require that a precursor be thinner than about 3'', and fainter than about 5% of the post-shock peak. These limits suggest that the magnetic field is amplified by a factor of seven or more in a narrow precursor region, promoting diffusive particle acceleration.

  15. Concentrating Solar Power and Water Issues in the U.S. Southwest

    SciTech Connect (OSTI)

    Bracken, N.; Macknick, J.; Tovar-Hastings, A.; Komor, P.; Gerritsen, M.; Mehta, S.

    2015-03-01

    Concentrating solar power (CSP) systems utilize the sun's energy to create heat that is used to generate electrical power. CSP systems in the United States are installed primarily in the Southwest, with 92% of plants that are operational, under construction, or under development located in three western states--Arizona, California, and Nevada. This report provides an overview of CSP development in these states, or the 'Southwest' for the purposes of this discussion, with a particular focus on the water supply issues associated with CSP. The Western Governors' Association (WGA) commissioned staff from the Western States Water Council (WSWC) to collaborate with staff from the National Renewable Energy Laboratory (NREL) to prepare this report. The WGA has long supported the effective management of the West's water resources, as well as the development of a clean, diverse, reliable, and affordable energy supply consisting of traditional and renewable energy resources. This report is specifically intended to help inform these goals, especially as WGA continues to underwrite a Regional Transmission Expansion Planning project, undertaken by the WSWC and the Western Electricity Coordinating Council (WECC), to better understand energy development within the existing and future water resource constraints of the West. This report builds upon earlier research conducted by NREL, the University of Colorado-Boulder, and Stanford University that was supported through the Joint Institute for Strategic Energy Analysis (JISEA) and presents information gathered through extensive research and literature reviews, as well as interviews and outreach with state water administrators and energy regulators, WECC and other experts familiar with CSP development in the Southwest.

  16. Enhanced presentation of MHC class Ia, Ib and class II-restricted peptides encapsulated in biodegradable nanoparticles: a promising strategy for tumor immunotherapy

    E-Print Network [OSTI]

    2011-01-01

    sequences enhance MHC class I presentation of a peptide fromantigens presented on MHC class I molecules. Science 1995,Enhanced presentation of MHC class Ia, Ib and class II-

  17. Constraints on shallow {sup 56}Ni from the early light curves of type Ia supernovae

    SciTech Connect (OSTI)

    Piro, Anthony L. [Theoretical Astrophysics, California Institute of Technology, 1200 E California Boulevard, M/C 350-17, Pasadena, CA 91125 (United States); Nakar, Ehud, E-mail: piro@caltech.edu [Raymond and Beverly Sackler School of Physics and Astronomy, Tel Aviv University, Tel Aviv 69978 (Israel)

    2014-03-20

    Ongoing transient surveys are presenting an unprecedented account of the rising light curves of Type Ia supernovae (SNe Ia). This early emission probes the shallowest layers of the exploding white dwarf (WD), which can provide constraints on the progenitor star and the properties of the explosive burning. We use semianalytic models of radioactively powered rising light curves to analyze these observations. As we have summarized in previous work, the main limiting factor in determining the surface distribution of {sup 56}Ni is the lack of an unambiguously identified time of explosion, as would be provided by detection of shock breakout or shock-heated cooling. Without this the SN may in principle exhibit a 'dark phase' for a few hours to days, where the only emission is from shock-heated cooling that is too dim to be detected. We show that by assuming a theoretically motivated time-dependent velocity evolution, the explosion time can be better constrained, albeit with potential systematic uncertainties. This technique is used to infer the surface {sup 56}Ni distributions of three recent SNe Ia that were caught especially early in their rise. In all three we find fairly similar {sup 56}Ni distributions. Observations of SN 2011fe and SN 2012cg probe shallower depths than SN 2009ig, and in these two cases {sup 56}Ni is present merely ?10{sup –2} M {sub ?} from the WDs' surfaces. The uncertainty in this result is up to an order of magnitude given the difficulty of precisely constraining the explosion time. We also use our conclusions about the explosion times to reassess radius constraints for the progenitor of SN 2011fe, as well as discuss the roughly t {sup 2} power law that is inferred for many observed rising light curves.

  18. IS WX CEN A POSSIBLE TYPE Ia SUPERNOVA PROGENITOR WITH WIND-DRIVEN MASS TRANSFER?

    SciTech Connect (OSTI)

    Qian, S.-B.; Shi, G.; Zhu, L.-Y.; Liu, L.; Zhao, E.-G.; Li, L.-J. [Yunnan Observatories, Chinese Academy of Sciences (CAS), P.O. Box 110, 650011 Kunming (China); Fernandez Lajus, E.; Di Sisto, R. P., E-mail: qsb@ynao.ac.cn [Facultad de Ciencias Astronomicas y Geofisicas, Universidad Nacional de La Plata, 1900 La Plata, Buenos Aires (Argentina)

    2013-08-01

    WX Cen is one of a few compact binary supersoft X-ray sources (CBSS) in the Galaxy that is a possible Type Ia supernova (SN Ia) progenitor. The supersoft X-ray radiation is explained as hydrostatic nuclear burning on the surface of the white dwarf component that is accreting hydrogen from a stellar companion at a high rate. If the mass donor in this system has a low mass, as has been suggested in the literature, one would expect a high wind-driven mass transfer rate. In that case, the orbital period of the system should increase. To test this theoretical prediction, we have monitored the system photometrically since 2010. By using four newly determined eclipse timings together with those collected from the literature, we discovered that the orbital period is decreasing at a rate of dP/dt = -5.15 Multiplication-Sign 10{sup -7} days yr{sup -1}. The long-term decrease in the orbital period is contrary to the prediction that the system is powered by wind-driven accretion. It therefore seems plausible that the mass donor could be more massive than the white dwarf, and that the mass transfer is driven by the thermal instability of the donor star. This finding suggests that WX Cen is a key object to check the physical mechanisms of mass accretion in CBSS. The corresponding timescale of the period change is about P/P-dot {approx} 0.81 x 10{sup 6} yr, indicating that WX Cen may evolve into an SNe Ia within one million years in the Galaxy.

  19. On the Thermonuclear Runaway in Type Ia Supernovae: How to run away?

    E-Print Network [OSTI]

    P. Hoeflich; J. Stein

    2001-12-07

    Type Ia Supernovae are thought to be thermonuclear explosions of massive white dwarfs (WD). We present the first study of multi-dimensional effects during the final hours prior to the thermonuclear runaway which leads to the explosion. The calculations utilize an implicit, 2-D hydro code.Mixing and the ignition process are studied in detail. We find that the initial chemical structure of the WD is changed but the material is not fully homogenized. The exploding WD sustains a central region with a low C/O ratio. This implies that the explosive nuclear burning will begin in a partially C-depleted environment. The thermonuclear runaway happens in a well defined region close to the center. It is induced by compressional heat when matter is brought inwards by convective flows. We find no evidence for multiple spot or strong off-center ignition. Convective velocities are of the order of 100 km/sec which is well above the effective burning speeds in SNe Ia previously expected right after the runaway. For about 0.5 to 1 sec, the speed of the burning front will neither be determined by the laminar speed nor the Rayleigh-Taylor instabilities but by convective flows produced prior to the runaway. The consequences are discussed for our under- standing of the detailed physics of the flame propagation, the deflagration detonation transition, and the nucleosynthesis in the central layers. Our results strongly suggest the pre-conditioning of the progenitor as a key-factor for our understanding of the diversity in SNeIa.

  20. SN~2012cg: Evidence for Interaction Between a Normal Type Ia Supernova and a Non-Degenerate Binary Companion

    E-Print Network [OSTI]

    Marion, G H; Vinkó, Jozsef; Silverman, Jeffrey M; Sand, David J; Challis, Peter; Kirshner, Robert P; Wheeler, J Craig; Berlind, Perry; Brown, Warren R; Calkins, Michael L; Dhungana, Govinda; Foley, Ryan J; Friedman, Andrew S; Graham, Melissa L; Howell, D Andrew; Hsiao, Eric Y; Irwin, Jonathan M; Kehoe, Robert; Macri, Lucas M; Mandel, Kaisey; McCully, Curtis; Rines, Kenneth J; Wilhelmy, Steven; Zheng, Weikang

    2015-01-01

    We report evidence for excess blue light from the Type Ia supernova SN~2012cg at fifteen and sixteen days before maximum B-band brightness. The emission is consistent with predictions for the impact of the supernova on a non-degenerate binary companion. This is the first evidence for emission from a companion to a normal SN~Ia. Sixteen days before maximum light, the B-V color of SN~2012cg is 0.2 mag bluer than for other normal SN~Ia. At later times, this supernova has a typical SN~Ia light curve, with extinction-corrected M_B = -19.62 \\pm 0.02 mag and Delta m_{15}(B) = 0.86 \\pm 0.02. Our data set is extensive, with photometry in 7 filters from 5 independent sources. Early spectra also show the effects of blue light, and high-velocity features are observed at early times. Near maximum, the spectra are normal with a silicon velocity v_{Si} = -10,500 km/s. Comparing the early data with models by Kasen (2010) favors a main-sequence companion of about 6 solar masses. It is possible that many other SN Ia have main-...

  1. Presented at the 2010 Rocky Mountain AAPG Section Meeting in Durango Colorado 1 Pre-and Post-injection Vertical Seismic Profiling over the Southwest Regional

    E-Print Network [OSTI]

    Wilson, Thomas H.

    -injection Vertical Seismic Profiling over the Southwest Regional Partnership's Phase II Fruitland Coal CO2 Pilot Tom of pre and post injection vertical seismic profiles collected at the Southwest Regional Partnership (SWP into the Fruitland coals. The pre-injection vertical seismic profiles were completed on June 2nd and 3rd of 2008

  2. On the Stability of Thermonuclear Burning Fronts in Type Ia Supernovae

    E-Print Network [OSTI]

    F. K. Roepke; W. Hillebrandt

    2004-04-26

    The propagation of cellularly stabilized thermonuclear flames is investigated by means of numerical simulations. In Type Ia supernova explosions the corresponding burning regime establishes at scales below the Gibson length. The cellular flame stabilization - which is a result of an interplay between the Landau-Darrieus instability and a nonlinear stabilization mechanism - is studied for the case of propagation into quiescent fuel as well as interaction with vortical fuel flows. Our simulations indicate that in thermonuclear supernova explosions stable cellular flames develop around the Gibson scale and that deflagration-to-detonation transition is unlikely to be triggered from flame evolution effects here.

  3. File:USDA-CE-Production-GIFmaps-IA.pdf | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QAsource History View New Pages RecentTempCampApplicationWorksheet 2011.pdf JumpTransmission SitingFL.pdf JumpIA.pdf

  4. IA REP0 SAND85-2809 Unlimited Release UC-92A

    Office of Scientific and Technical Information (OSTI)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of NaturalDukeWakefield MunicipalTechnical Report:Speeding accessby aLED Street LightingFrom theHighI _ _ ORNL-6161 OAK*I.IA

  5. Type Ia supernovae yielding distances with 3-4% precision (Journal Article)

    Office of Scientific and Technical Information (OSTI)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of NaturalDukeWakefieldSulfateSciTechtail.Theory of rare Kaon and(Conference) | SciTech(2D-CARS):| SciTech Connect Type Ia

  6. Type Ia supernovae yielding distances with 3-4% precision (Journal Article)

    Office of Scientific and Technical Information (OSTI)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of NaturalDukeWakefieldSulfateSciTechtail.Theory of rare Kaon and(Conference) | SciTech(2D-CARS):| SciTech Connect Type Ia|

  7. TYCHO SN 1572: A NAKED Ia SUPERNOVA REMNANT WITHOUT AN ASSOCIATED AMBIENT MOLECULAR CLOUD

    SciTech Connect (OSTI)

    Tian, W. W.; Leahy, D. A.

    2011-03-10

    The historical supernova remnant (SNR) Tycho SN 1572 originates from the explosion of a normal Type Ia supernova that is believed to have originated from a carbon-oxygen white dwarf in a binary system. We analyze the 21 cm continuum, H I, and {sup 12}CO-line data from the Canadian Galactic Plane Survey in the direction of SN 1572 and the surrounding region. We construct H I absorption spectra to SN 1572 and three nearby compact sources. We conclude that SN 1572 has no molecular cloud interaction, which argues against previous claims that a molecular cloud is interacting with the SNR. This new result does not support a recent claim that dust, newly detected by AKARI, originates from such an SNR-cloud interaction. We suggest that the SNR has a kinematic distance of 2.5-3.0 kpc based on a nonlinear rotational curve model. Very high energy {gamma}-ray emission from the remnant has been detected by the VERITAS telescope, so our result shows that its origin should not be an SNR-cloud interaction. Both radio and X-ray observations support that SN 1572 is an isolated Type Ia SNR.

  8. Smoothed Particle Hydrodynamics simulations of the core-degenerate scenario for Type Ia supernovae

    E-Print Network [OSTI]

    Aznar-Siguán, G; Lorén-Aguilar, P; Soker, N; Kashi, A

    2015-01-01

    The core-degenerate (CD) scenario for type Ia supernovae (SN Ia) involves the merger of the hot core of an asymptotic giant branch (AGB) star and a white dwarf, and might contribute a non-negligible fraction of all thermonuclear supernovae. Despite its potential interest, very few studies, and based on only crude simplifications, have been devoted to investigate this possible scenario, compared with the large efforts invested to study some other scenarios. Here we perform the first three-dimensional simulations of the merger phase, and find that this process can lead to the formation of a massive white dwarf, as required by this scenario. We consider two situations, according to the mass of the circumbinary disk formed around the system during the final stages of the common envelope phase. If the disk is massive enough, the stars merge on a highly eccentric orbit. Otherwise, the merger occurs after the circumbinary disk has been ejected and gravitational wave radiation has brought the stars close to the Roche...

  9. Variable Selection for Modeling the Absolute Magnitude at Maximum of Type Ia Supernovae

    E-Print Network [OSTI]

    Uemura, Makoto; Kawabata, S; Ikeda, Shiro; Maeda, Keiichi

    2015-01-01

    We discuss what is an appropriate set of explanatory variables in order to predict the absolute magnitude at the maximum of Type Ia supernovae. In order to have a good prediction, the error for future data, which is called the "generalization error," should be small. We use cross-validation in order to control the generalization error and LASSO-type estimator in order to choose the set of variables. This approach can be used even in the case that the number of samples is smaller than the number of candidate variables. We studied the Berkeley supernova database with our approach. Candidates of the explanatory variables include normalized spectral data, variables about lines, and previously proposed flux-ratios, as well as the color and light-curve widths. As a result, we confirmed the past understanding about Type Ia supernova: i) The absolute magnitude at maximum depends on the color and light-curve width. ii) The light-curve width depends on the strength of Si II. Recent studies have suggested to add more va...

  10. Spectroscopic Observations and Analysis of the Unusual Type Ia SN1999ac

    SciTech Connect (OSTI)

    Garavini, G.; Aldering, G.; Amadon, A.; Amanullah, R.; Astier,P.; Balland, C.; Blanc, G.; Conley, A.; Dahlen, T.; Deustua, S.E.; Ellis,R.; Fabbro, S.; Fadeyev, V.; Fan, X.; Folatelli, G.; Frye, B.; Gates,E.L.; Gibbons, R.; Goldhaber, G.; Goldman, B.; Goobar, A.; Groom, D.E.; Haissinski, J.; Hardin, D.; Hook, I.; Howell, D.A.; Kent, S.; Kim, A.G.; Knop, R.A.; Kowalski, M.; Kuznetsova, N.; Lee, B.C.; Lidman, C.; Mendez,J.; Miller, G.J.; Moniez, M.; Mouchet, M.; Mourao, A.; Newberg, H.; Nobili, S.; Nugent, P.E.; Pain, R.; Perdereau, O.; Perlmutter, S.; Quimby, R.; Regnault, N.; Rich, J.; Richards, G.T.; Ruiz-Lapuente, P.; Schaefer, B.E.; Schahmaneche, K.; Smith, E.; Spadafora, A.L.; Stanishev,V.; Thomas, R.C.; Walton, N.A.; Wang, L.; Wood-Vasey, W.M.

    2005-07-12

    The authors present optical spectra of the peculiar Type Ia supernova (SN Ia) 1999ac. The data extend from -15 to +42 days with respect to B-band maximum and reveal an event that is unusual in several respects. prior to B-band maximum, the spectra resemble those of SN 1999aa, a slowly declining event, but possess stronger Si II and Ca II signatures (more characteristic of a spectroscopically normal SN). Spectra after B-band maximum appear more normal. The expansion velocities inferred from the Iron lines appear to be lower than average; whereas, the expansion velocity inferred from Calcium H and K are higher than average. The expansion velocities inferred from the Iron lines appear to be lower than average; whereas, the expansion velocity inferred from Calcium H and K are higher than average. The expansion velocities inferred from Si II are among the slowest ever observed, though SN 1999ac is not particularly dim. The analysis of the parameters v{sub 10}(Si II), R(Si II), v, and {Delta}m{sub 15} further underlines the unique characteristics of SN 1999ac. They find convincing evidence of C II {lambda}6580 in the day -15 spectrum with ejection velocity v > 16,000 km s{sup -1}, but this signature disappears by day -9. This rapid evolution at early times highlights the importance of extremely early-time spectroscopy.

  11. Consistent use of type Ia supernovae highly magnified by galaxy clusters to constrain the cosmological parameters

    SciTech Connect (OSTI)

    Zitrin, Adi [Cahill Center for Astronomy and Astrophysics, California Institute of Technology, MS 249-17, Pasadena, CA 91125 (United States); Redlich, Matthias [Universität Heidelberg, Zentrum für Astronomie, Institut für Theoretische Astrophysik, Philosophenweg 12, D-69120 Heidelberg (Germany); Broadhurst, Tom, E-mail: adizitrin@gmail.com [Department of Theoretical Physics, University of Basque Country UPV/EHU, Bilbao (Spain)

    2014-07-01

    We discuss how Type Ia supernovae (SNe) strongly magnified by foreground galaxy clusters should be self-consistently treated when used in samples fitted for the cosmological parameters. While the cluster lens magnification of a SN can be well constrained from sets of multiple images of various background galaxies with measured redshifts, its value is typically dependent on the fiducial set of cosmological parameters used to construct the mass model. In such cases, one should not naively demagnify the observed SN luminosity by the model magnification into the expected Hubble diagram, which would create a bias, but instead take into account the cosmological parameters a priori chosen to construct the mass model. We quantify the effect and find that a systematic error of typically a few percent, up to a few dozen percent per magnified SN may be propagated onto a cosmological parameter fit unless the cosmology assumed for the mass model is taken into account (the bias can be even larger if the SN is lying very near the critical curves). We also simulate how such a bias propagates onto the cosmological parameter fit using the Union2.1 sample supplemented with strongly magnified SNe. The resulting bias on the deduced cosmological parameters is generally at the few percent level, if only few biased SNe are included, and increases with the number of lensed SNe and their redshift. Samples containing magnified Type Ia SNe, e.g., from ongoing cluster surveys, should readily account for this possible bias.

  12. Supercal: Cross-Calibration of Multiple Photometric Systems to Improve Cosmological Measurements with Type Ia Supernovae

    E-Print Network [OSTI]

    Scolnic, D; Riess, A G; Rest, A; Schlafly, E; Foley, R J; Finkbeiner, D; Tang, C; Burgett, W S; Chambers, K C; Draper, P W; Hodapp, K W; Huber, M E; Kaiser, N; Kudritzki, R P; Magnier, E A; Metcalfe, N; Stubbs, C W

    2015-01-01

    Current cosmological analyses which use Type Ia supernova (SN Ia) observations combine SN samples to expand the redshift range beyond that of a single sample and increase the overall sample size. The inhomogeneous photometric calibration between different SN samples is one of the largest systematic uncertainties of the cosmological parameter estimation. To place these different samples on a single system, analyses currently use observations of a small sample of very bright flux standards on the $HST$ system. We propose a complementary method, called `Supercal', in which we use measurements of secondary standards in each system, compare these to measurements of the same stars in the Pan-STARRS1 (PS1) system, and determine offsets for each system relative to PS1, placing all SN observations on a single, consistent photometric system. PS1 has observed $3\\pi$ of the sky and has a relative calibration of better than 5 mmag (for $\\sim15

  13. Convection during the Late Stages of Simmering in Type Ia Supernovae

    E-Print Network [OSTI]

    Piro, Anthony L

    2008-01-01

    Following unstable ignition of carbon, but prior to explosion, a white dwarf (WD) in a Type Ia supernova (SN Ia) undergoes a simmering phase. During this time, a central convective region grows and encompasses ~1 Msun of the WD over a timescale of ~1000 yrs, which sets the thermal and turbulent profile for the subsequent explosion. We study this time-dependent convection and summarize some of the key features that differ from the traditional, steady-state case. We show that the long conductive timescale above the convective zone and the extraction of energy to heat the WD core leads to a decrease of the convective luminosity and characteristic velocities near the convective zone's top boundary. In addition, differences in the composition between the convective core and the conductive exterior will significantly alter the location of this boundary. In this respect, we find the biggest effect due to complete 22Ne sedimentation prior to carbon ignition. These effects add diversity to the possible WD models, whic...

  14. Spectroscopic Determination of the Low Redshift Type Ia Supernova Rate from the Sloan Digital Sky Survey

    SciTech Connect (OSTI)

    Krughoff, K. S.; Connolly, Andrew J.; Frieman, Joshua; SubbaRao, Mark; Kilper, Gary; Schneider, Donald P.

    2011-04-10

    Supernova rates are directly coupled to high mass stellar birth and evolution. As such, they are one of the few direct measures of the history of cosmic stellar evolution. In this paper we describe an probabilistic technique for identifying supernovae within spectroscopic samples of galaxies. We present a study of 52 type Ia supernovae ranging in age from -14 days to +40 days extracted from a parent sample of \\simeq 50,000 spectra from the SDSS DR5. We find a Supernova Rate (SNR) of 0.472^{+0.048}_{-0.039}(Systematic)^{+0.081}_{-0.071}(Statistical)SNu at a redshift of = 0.1. This value is higher than other values at low redshift at the 1{\\sigma}, but is consistent at the 3{\\sigma} level. The 52 supernova candidates used in this study comprise the third largest sample of supernovae used in a type Ia rate determination to date. In this paper we demonstrate the potential for the described approach for detecting supernovae in future spectroscopic surveys.

  15. First Evidence of Globular Cluster Formation from the Ejecta of Prompt Type Ia Supernovae

    E-Print Network [OSTI]

    Tsujimoto, Takuji

    2012-01-01

    Recent spectroscopic observations of globular clusters (GCs) in the Large Magellanic Cloud (LMC) have discovered that one of the intermediate-age GC, NGC 1718 with [Fe/H]=-0.7 has an extremely low [Mg/Fe] ratio of ~-0.9. We propose that NGC 1718 was formed from the ejecta of type Ia supernovae (SNe Ia) mixed with very metal-poor ([Fe/H] <-1.3) gas about ~ 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 the 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.

  16. A Generalized {ital K} Correction for Type Ia Supernovae: Comparing {ital R}-band Photometry Beyond {ital z=9.2} with B,V, and {ital R}-band Nearby Photometry

    E-Print Network [OSTI]

    Goodbar, Ariel

    2008-01-01

    spectroscopically peculiar supernovae, and to search for anyK Correction for Type Ia Supernovae: Comparing R-bandK Correction for Type Ia Supernovae: Comparing R-band

  17. EIS-0443: Project Financing for Southwest Intertie Project- South, Clark, Lincoln, Nye, and White Pine Counties, Nevada

    Broader source: Energy.gov [DOE]

    The U.S. Department of Energy (DOE), Western Area Power Administration, is considering whether to provide partial financing of the southern portion of the Southwest lntertie Project (SWIP-South) which consists of approximately 235 miles of 500- kilovolt (kV) transmission line.

  18. Modeling the Summertime Climate of Southwest Asia: The Role of Land Surface Processes in Shaping the Climate of Semiarid Regions

    E-Print Network [OSTI]

    Marcella, Marc P.

    Presented is a study on the role of land surface processes in determining the summertime climate over the semiarid region of southwest Asia. In this region, a warm surface air temperature bias of 3.5°C is simulated in the ...

  19. Seismic anisotropy in the wedge above the Philippine Sea slab beneath Kanto and southwest Japan derived from shear wave splitting

    E-Print Network [OSTI]

    Seno, Tetsuzo

    Seismic anisotropy in the wedge above the Philippine Sea slab beneath Kanto and southwest Japan generated by shallow and intermediate-depth earthquakes occurring in the subducting Philippine Sea are further divided into PHS1 and PHS2 (upper and lower planes of the double seismic zone in the Philippine

  20. Investigating New Polymers for a Chlorine Tolerant RO Membrane Southwest Center for Education and the Natural Environment (SCENE)

    E-Print Network [OSTI]

    Hall, Sharon J.

    Investigating New Polymers for a Chlorine Tolerant RO Membrane Southwest Center for Education of such a polymer could poten(ally enable our u(liza(on of addi(onal water sources, thereby(gate new polymers for a more chlorine tolerant membrane. We tested Acrylonitrile

  1. LATE-TIME SPECTRAL OBSERVATIONS OF THE STRONGLY INTERACTING TYPE Ia SUPERNOVA PTF11kx

    SciTech Connect (OSTI)

    Silverman, Jeffrey M. [Department of Astronomy, University of Texas, Austin, TX 78712-0259 (United States); Nugent, Peter E.; Filippenko, Alexei V.; Cenko, S. Bradley [Department of Astronomy, University of California, Berkeley, CA 94720-3411 (United States); Gal-Yam, Avishay [Benoziyo Center for Astrophysics, The Weizmann Institute of Science, Rehovot 76100 (Israel); Sullivan, Mark [School of Physics and Astronomy, University of Southampton, Southampton SO17 1BJ (United Kingdom); Howell, D. Andrew [Las Cumbres Observatory Global Telescope Network, Goleta, CA 93117 (United States); Pan, Yen-Chen; Hook, Isobel M., E-mail: jsilverman@astro.as.utexas.edu [Department of Physics (Astrophysics), University of Oxford, Keble Road, Oxford OX1 3RH (United Kingdom)

    2013-08-01

    PTF11kx was a Type Ia supernova (SN Ia) that showed time-variable absorption features, including saturated Ca II H and K lines that weakened and eventually went into emission. The strength of the emission component of H{alpha} gradually increased, implying that the SN was undergoing significant interaction with its circumstellar medium (CSM). These features, and many others, were blueshifted slightly and showed a P-Cygni profile, likely indicating that the CSM was directly related to, and probably previously ejected by, the progenitor system itself. These and other observations led Dilday et al. to conclude that PTF11kx came from a symbiotic nova progenitor like RS Oph. In this work we extend the spectral coverage of PTF11kx to 124-680 rest-frame days past maximum brightness. The late-time spectra of PTF11kx are dominated by H{alpha} emission (with widths of full width at half-maximum intensity Almost-Equal-To 2000 km s{sup -1}), strong Ca II emission features ({approx}10,000 km s{sup -1} wide), and a blue 'quasi-continuum' due to many overlapping narrow lines of Fe II. Emission from oxygen, He I, and Balmer lines higher than H{alpha} is weak or completely absent at all epochs, leading to large observed H{alpha}/H{beta} intensity ratios. The H{alpha} emission appears to increase in strength with time for {approx}1 yr, but it subsequently decreases significantly along with the Ca II emission. Our latest spectrum also indicates the possibility of newly formed dust in the system as evidenced by a slight decrease in the red wing of H{alpha}. During the same epochs, multiple narrow emission features from the CSM temporally vary in strength. The weakening of the H{alpha} and Ca II emission at late times is possible evidence that the SN ejecta have overtaken the majority of the CSM and agrees with models of other strongly interacting SNe Ia. The varying narrow emission features, on the other hand, may indicate that the CSM is clumpy or consists of multiple thin shells.

  2. The ESO/VLT 3rd year Type Ia supernova data set from the Supernova Legacy Survey

    E-Print Network [OSTI]

    Balland, C; Basa, S; Mouchet, M; Howell, D A; Astier, P; Carlberg, R G; Conley, A; Fouchez, D; Guy, J; Hardin, D; Hook, I M; Pain, R; Perrett, K; Pritchet, C J; Regnault, N; Rich, J; Sullivan, M; Antilogus, P; Arsenijevic, V; Du, J Le; Fabbro, S; Lidman, C; Mourao, A; Palanque-Delabrouille, Nathalie; Pécontal, E; Ruhlmann-Kleider, V

    2009-01-01

    We present 139 spectra of 124 Type Ia supernovae (SNeIa) that were observed at the ESO/VLT during the first three years of the Canada-France-Hawai Telescope (CFHT) Supernova Legacy Survey (SNLS). This homogeneous data set is used to test for redshift evolution of SNeIa spectra, and will be used in the SNLS 3rd year cosmological analyses. Spectra have been reduced and extracted with a dedicated pipeline that uses photometric information from deep CFHT Legacy Survey (CFHT-LS) reference images to trace, at sub-pixel accuracy, the position of the supernova on the spectrogram as a function of wavelength. It also separates the supernova and its host light in 60% of cases. The identification of the supernova candidates is performed using a spectrophotometric SNIa model. A total of 124 SNeIa, roughly 50% of the overall SNLS spectroscopic sample, have been identified using the ESO/VLT during the first three years of the survey. Their redshifts range from z=0.149 to z=1.031. The average redshift of the sample is z=0.63...

  3. The Joint Efficient Dark-energy Investigation (JEDI): Measuring the cosmic expansion history from type Ia supernovae

    E-Print Network [OSTI]

    M. M. Phillips; Peter Garnavich; Yun Wang; David Branch; Edward Baron; Arlin Crotts; J. Craig Wheeler; Edward Cheng; Mario Hamuy; for the JEDI Team

    2006-06-28

    JEDI (Joint Efficient Dark-energy Investigation) is a candidate implementation of the NASA-DOE Joint Dark Energy Mission (JDEM). JEDI will probe dark energy in three independent methods: (1) type Ia supernovae, (2) baryon acoustic oscillations, and (3) weak gravitational lensing. In an accompanying paper, an overall summary of the JEDI mission is given. In this paper, we present further details of the supernova component of JEDI. To derive model-independent constraints on dark energy, it is important to precisely measure the cosmic expansion history, H(z), in continuous redshift bins from z \\~ 0-2 (the redshift range in which dark energy is important). SNe Ia at z > 1 are not readily accessible from the ground because the bulk of their light has shifted into the near-infrared where the sky background is overwhelming; hence a space mission is required to probe dark energy using SNe. Because of its unique near-infrared wavelength coverage (0.8-4.2 microns), JEDI has the advantage of observing SNe Ia in the rest frame J band for the entire redshift range of 0 operations, spectra and light curves will be obtained for ~4,000 SNe Ia at z < 2. The resulting constraints on dark energy are discussed, with special emphasis on the improved precision afforded by the rest frame near-infrared data.

  4. Significantly super-Chandrasekhar limiting mass white dwarfs as progenitors for peculiar over-luminous type Ia supernovae

    E-Print Network [OSTI]

    Mukhopadhyay, Banibrata

    2015-01-01

    Since 2012, we have initiated developing systematically the simplistic to rigorous models to prove that highly super-Chandrasekhar, as well as highly sub-Chandrasekhar, limiting mass white dwarfs are possible to exist. We show that the mass of highly magnetized or modified Einstein's gravity induced white dwarfs could be significantly super-Chandrasekhar and such white dwarfs could altogether have a different mass-limit. On the other hand, type Ia supernovae (SNeIa), a key to unravel the evolutionary history of the universe, are believed to be triggered in white dwarfs having mass close to the Chandrasekhar-limit. However, observations of several peculiar, over- and under-luminous SNeIa argue for exploding masses widely different from this limit. We argue that explosions of super-Chandrasekhar limiting mass white dwarfs result in over-luminous SNeIa. We arrive at this revelation, first by considering simplistic, spherical, Newtonian white dwarfs with constant magnetic fields. Then we relax the Newtonian assum...

  5. Experto Universitario Java Enterprise Componentes de presentacin 2012-2013 Depto. Ciencia de la Computacin e IA Sesin 1

    E-Print Network [OSTI]

    Escolano, Francisco

    Experto Universitario Java Enterprise Componentes de presentación © 2012-2013 Depto. Ciencia de la Universitario Java Enterprise Componentes de presentación © 2012-2013 Depto. Ciencia de la Computación e IA Sesión 1 Experto Universitario Java Enterprise · Framewoks RIA basados en el servidor · Características

  6. Utilizing the Updated Gamma-Ray Bursts and Type Ia Supernovae to Constrain the Cardassian Expansion Model and Dark Energy

    E-Print Network [OSTI]

    Wei, Jun-Jie; Wu, Xue-Feng

    2015-01-01

    We update gamma-ray burst (GRB) luminosity relations among certain spectral and light-curve features with 139 GRBs. The distance modulus of 82 GRBs at $z>1.4$ can be calibrated with the sample at $z\\leq1.4$ by using the cubic spline interpolation method from the Union2.1 Type Ia supernovae (SNe Ia) set. We investigate the joint constraints on the Cardassian expansion model and dark energy with 580 Union2.1 SNe Ia sample ($z<1.4$) and 82 calibrated GRBs data ($1.4Ia significantly improves the constrain on $\\Omega_{m}-\\Omega_{\\Lambda}$ plane. In the Cardassian expansion model, the best fit is $\\Omega_{m}= 0.24_{-0.15}^{+0.15}$ and $n=0.16_{-0.52}^{+0.30}$ $(1\\sigma)$, which is consistent with the $\\Lambda$CDM cosmology $(n=0)$ in the $1\\sigma$ confidence region. We also discuss two dark energy models in which the equation of state $w(z)$ is parametrized as $w(z)=w_{0}$ and $w(z)=w_{0}+w_{1}z/(1+z)$, respectively. Based on o...

  7. On the Semiclassical Jacobi Algorithm \\Lambda Mar'ia T. C'amara and Domingo Gim'enez y

    E-Print Network [OSTI]

    Giménez, Domingo

    Chapter 1 On the Semiclassical Jacobi Algorithm \\Lambda Mar'ia T. C'amara and Domingo Gim'enez y Abstract In this paper a new Jacobi method to solve the symmetric eigenvalue problem is presented Jacobi methods. By combining this method with an adequate threshold strategy a reduction in the execution

  8. Late-Time Photometry of Type Ia Supernova SN2012cg Reveals the Radioactive Decay of $^{57}$Co

    E-Print Network [OSTI]

    Graur, Or; Shara, Michael M; Riess, Adam G

    2015-01-01

    Seitenzahl et al. (2009) have predicted that $\\sim 3$ years after its explosion, the light we receive from a Type Ia supernova will come mostly from reprocessing of electrons and X-rays emitted by the radioactive decay chain $^{57}{\\rm Co}~\\to~^{57}{\\rm Fe}$, instead of positrons from the decay chain $^{56}{\\rm Co}~\\to~^{56}{\\rm Fe}$ that dominates the supernova light at earlier times. Using the Hubble Space Telescope, we followed the light curve of the Type Ia supernova SN2012cg out to $1055$ days after maximum light. Our measurements are consistent with the light curves predicted by the contribution of energy from the reprocessing of electrons and X-rays emitted by the decay of $^{57}$Co. This provides conclusive evidence that $^{57}$Co is produced in Type Ia supernova explosions. The ratio of luminosities produced by the decays of $^{57}$Co and $^{56}$Co, a strong constraint on any Type Ia supernova explosion model, is in the range $(0.4$ - $8.5)\\times10^{-3}$.

  9. STANDARDIZING TYPE Ia SUPERNOVA ABSOLUTE MAGNITUDES USING GAUSSIAN PROCESS DATA REGRESSION

    SciTech Connect (OSTI)

    Kim, A. G.; Aldering, G.; Aragon, C.; Bailey, S.; Childress, M.; Fakhouri, H. K.; Nordin, J. [Physics Division, Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, CA 94720 (United States)] [Physics Division, Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, CA 94720 (United States); Thomas, R. C. [Computational Cosmology Center, Computational Research Division, Lawrence Berkeley National Laboratory, 1 Cyclotron Road MS 50B-4206, Berkeley, CA 94720 (United States)] [Computational Cosmology Center, Computational Research Division, Lawrence Berkeley National Laboratory, 1 Cyclotron Road MS 50B-4206, Berkeley, CA 94720 (United States); Antilogus, P.; Bongard, S.; Canto, A.; Cellier-Holzem, F.; Guy, J. [Laboratoire de Physique Nucleaire et des Hautes Energies, Universite Pierre et Marie Curie Paris 6, Universite Denis Diderot Paris 7, CNRS-IN2P3, 4 place Jussieu, F-75252 Paris Cedex 05 (France)] [Laboratoire de Physique Nucleaire et des Hautes Energies, Universite Pierre et Marie Curie Paris 6, Universite Denis Diderot Paris 7, CNRS-IN2P3, 4 place Jussieu, F-75252 Paris Cedex 05 (France); Baltay, C. [Department of Physics, Yale University, New Haven, CT 06250-8121 (United States)] [Department of Physics, Yale University, New Haven, CT 06250-8121 (United States); Buton, C.; Kerschhaggl, M.; Kowalski, M. [Physikalisches Institut, Universitaet Bonn, Nussallee 12, D-53115 Bonn (Germany)] [Physikalisches Institut, Universitaet Bonn, Nussallee 12, D-53115 Bonn (Germany); Chotard, N. [Tsinghua Center for Astrophysics, Tsinghua University, Beijing 100084 (China)] [Tsinghua Center for Astrophysics, Tsinghua University, Beijing 100084 (China); Copin, Y.; Gangler, E. [Universite de Lyon, F-69622 Lyon (France)] [Universite de Lyon, F-69622 Lyon (France); and others

    2013-04-01

    We present a novel class of models for Type Ia supernova time-evolving spectral energy distributions (SEDs) and absolute magnitudes: they are each modeled as stochastic functions described by Gaussian processes. The values of the SED and absolute magnitudes are defined through well-defined regression prescriptions, so that data directly inform the models. As a proof of concept, we implement a model for synthetic photometry built from the spectrophotometric time series from the Nearby Supernova Factory. Absolute magnitudes at peak B brightness are calibrated to 0.13 mag in the g band and to as low as 0.09 mag in the z = 0.25 blueshifted i band, where the dispersion includes contributions from measurement uncertainties and peculiar velocities. The methodology can be applied to spectrophotometric time series of supernovae that span a range of redshifts to simultaneously standardize supernovae together with fitting cosmological parameters.

  10. Small-scale Interaction of Turbulence with Thermonuclear Flames in Type Ia Supernovae

    E-Print Network [OSTI]

    J. C. Niemeyer; W. K. Bushe; G. R. Ruetsch

    1999-05-07

    Microscopic turbulence-flame interactions of thermonuclear fusion flames occuring in Type Ia Supernovae were studied by means of incompressible direct numerical simulations with a highly simplified flame description. The flame is treated as a single diffusive scalar field with a nonlinear source term. It is characterized by its Prandtl number, Pr << 1, and laminar flame speed, S_L. We find that if S_L ~ u', where u' is the rms amplitude of turbulent velocity fluctuations, the local flame propagation speed does not significantly deviate from S_L even in the presence of velocity fluctuations on scales below the laminar flame thickness. This result is interpreted in the context of subgrid-scale modeling of supernova explosions and the mechanism for deflagration-detonation-transitions.

  11. Near-infrared line identification in type Ia supernovae during the transitional phase

    SciTech Connect (OSTI)

    Friesen, Brian; Baron, E.; Wisniewski, John P.; Miller, Timothy R. [Homer L. Dodge Department of Physics and Astronomy, 440 West Brooks Street, Room 100, Norman, OK 73019 (United States); Parrent, Jerod T. [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Thomas, R. C. [Computational Cosmology Center, Computational Research Division, Lawrence Berkeley National Laboratory, 1 Cyclotron Road MS 50B-4206, Berkeley, CA 94720 (United States); Marion, G. H. [University of Texas at Austin, 1 University Station C1400, Austin, TX 78712-0259 (United States)

    2014-09-10

    We present near-infrared synthetic spectra of a delayed-detonation hydrodynamical model and compare them to observed spectra of four normal Type Ia supernovae ranging from day +56.5 to day +85. This is the epoch during which supernovae are believed to be undergoing the transition from the photospheric phase, where spectra are characterized by line scattering above an optically thick photosphere, to the nebular phase, where spectra consist of optically thin emission from forbidden lines. We find that most spectral features in the near-infrared can be accounted for by permitted lines of Fe II and Co II. In addition, we find that [Ni II] fits the emission feature near 1.98 ?m, suggesting that a substantial mass of {sup 58}Ni exists near the center of the ejecta in these objects, arising from nuclear burning at high density.

  12. The $m$-$z$ relation for Type Ia supernovae: safety in numbers or safely without worry?

    E-Print Network [OSTI]

    Helbig, Phillip

    2015-01-01

    The $m$-$z$ relation for Type Ia supernovae is compatible with the cosmological concordance model if one assumes that the Universe is homogeneous, at least with respect to light propagation. This could be due to the density along each line of sight being equal to the overall cosmological density, or to `safety in numbers', with variation in the density along all lines of sight averaging out if the sample is large enough. Statistical correlations (or lack thereof) between redshifts, residuals (differences between the observed distance moduli and those calculated from the best-fitting cosmological model), and observational uncertainties suggest that the former scenario is the better description, so that one can use the traditional formula for the luminosity distance safely without worry.

  13. The Internal Shear of Type Ia Supernova Progenitors During Accretion and Simmering

    E-Print Network [OSTI]

    Piro, Anthony L

    2008-01-01

    A white dwarf (WD) gains substantial angular momentum during the accretion process that grows it toward a Chandrasekhar mass. It is therefore expected to be quickly rotating when it ignites as a Type Ia supernova. The thermal and shearing profile are important for subsequent flame propagation. We highlight processes that could affect the WD shear, during accretion as well as during the ~1000 years of pre-explosive simmering. Baroclinic instabilities and/or the shear growth of small magnetic fields provide sufficient torque to bring the WD very close to solid body rotation during accretion. The lack of significant shear makes it difficult to grow a WD substantially past the typical Chandrasekhar mass. Once carbon ignites, a convective region spreads from the WD's center. This phase occurs regardless of progenitor scenario, and therefore it is of great interest for understanding how the WD interior is prepared before the explosive burning begins. We summarize some of the key properties of the convective region,...

  14. Incompatibility of a comoving Ly-alpha forest with supernova-Ia luminosity distances

    E-Print Network [OSTI]

    Jens Thomas; Hartmut Schulz

    2001-03-18

    Recently Perlmutter et al. suggested a positive value of Einstein's cosmological constant Lambda on the basis of luminosity distances from type-Ia supernovae. However, Lambda world models had earlier been proposed by Hoell & Priester and Liebscher et al. on the basis of quasar absorption-line data. Employing more general repulsive fluids ("dark energy") encompassing the Lambda component we quantitatively compare both approaches with each other. Fitting the SN-data by a minimum-component model consisting of dark energy + dust yields a closed universe with a large amount of dust exceeding the baryonic content constrained by big-bang nucleosynthesis. The nature of the dark energy is hardly constrained. Only when enforcing a flat universe there is a clear tendency to a dark-energy Lambda fluid and the `canonical' value Omega_M = 0.3 for dust. Conversely, fitting the quasar-data by a minimum-component model yields a sharply defined, slightly closed model with a low dust density ruling out significant pressureless dark matter. The dark-energy component obtains an equation-of-state P = -0.96 epsilon close to that of a Lambda-fluid. Omega_M = 0.3 or a precisely flat spatial geometry are inconsistent with minimum-component models. It is found that quasar and supernova data sets cannot be reconciled with each other via (repulsive ideal fluid+dust+radiation)-world models. Compatibility could be reached by drastic expansion of the parameter space with at least two exotic fluids added to dust and radiation as world constituents. If considering such solutions as far-fetched one has to conclude that the quasar absorption line and the SN-Ia constraints are incompatible.

  15. EARLY OBSERVATIONS AND ANALYSIS OF THE TYPE Ia SN 2014J IN M82

    SciTech Connect (OSTI)

    Marion, G. H.; Vinkó, J. [University of Texas at Austin, 1 University Station C1400, Austin, TX 78712-0259 (United States); Sand, D. J. [Physics Department, Texas Tech University, Lubbock, TX 79409 (United States); Hsiao, E. Y. [Carnegie Observatories, Las Campanas Observatory, Colina El Pino, Casilla 601 (Chile); Banerjee, D. P. K.; Joshi, V.; Venkataraman, V.; Ashok, N. M. [Astronomy and Astrophysics Division, Physical Research Laboratory, Navrangapura, Ahmedabad - 380009, Gujarat (India); Valenti, S.; Howell, D. A. [Las Cumbres Observatory Global Telescope Network, 6740 Cortona Drive, Suite 102, Santa Barbara, CA 93117 (United States); Stritzinger, M. D. [Department of Physics and Astronomy, Aarhus University, Ny Munkegade 120, DK-8000 Aarhus C (Denmark); Amanullah, R.; Johansson, J. [The Oskar Klein Centre, Physics Department, Stockholm University, Albanova University Center, SE 106 91 Stockholm (Sweden); Binzel, R. P. [Department of Earth, Atmospheric, and Planetary Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139 (United States); Bochanski, J. J. [Haverford College, 370 Lancaster Avenue, Haverford, PA 19041 (United States); Bryngelson, G. L. [Department of Physics and Astronomy, Francis Marion University, 4822 East Palmetto Street, Florence, SC 29506 (United States); Burns, C. R. [Observatories of the Carnegie Institution for Science, 813 Santa Barbara Street, Pasadena, CA 91101 (United States); Drozdov, D. [Department of Physics and Astronomy, Clemson University, 8304 University Station, Clemson, SC 29634 (United States); Fieber-Beyer, S. K. [Department of Space Studies, University of North Dakota, University Stop 9008, ND 58202 (United States); Graham, M. L., E-mail: hman@astro.as.utexas.edu [Astronomy Department, University of California at Berkeley, Berkeley, CA 94720 (United States); and others

    2015-01-01

    We present optical and near infrared (NIR) observations of the nearby Type Ia SN 2014J. Seventeen optical and 23 NIR spectra were obtained from 10 days before (–10d) to 10 days after (+10d) the time of maximum B-band brightness. The relative strengths of absorption features and their patterns of development can be compared at one day intervals throughout most of this period. Carbon is not detected in the optical spectra, but we identify C I ?1.0693 in the NIR spectra. Mg II lines with high oscillator strengths have higher initial velocities than other Mg II lines. We show that the velocity differences can be explained by differences in optical depths due to oscillator strengths. The spectra of SN 2014J show that it is a normal SN Ia, but many parameters are near the boundaries between normal and high-velocity subclasses. The velocities for O I, Mg II, Si II, S II, Ca II, and Fe II suggest that SN 2014J has a layered structure with little or no mixing. That result is consistent with the delayed detonation explosion models. We also report photometric observations, obtained from –10d to +29d, in the UBVRIJH and K{sub s} bands. The template fitting package SNooPy is used to interpret the light curves and to derive photometric parameters. Using R{sub V} = 1.46, which is consistent with previous studies, SNooPy finds that A{sub V} = 1.80 for E(B – V){sub host} = 1.23 ± 0.06 mag. The maximum B-band brightness of –19.19 ± 0.10 mag was reached on February 1.74 UT ± 0.13 days and the supernova has a decline parameter, ?m {sub 15}, of 1.12 ± 0.02 mag.

  16. Sensitivity study of explosive nucleosynthesis in Type Ia supernovae: I. Modification of individual thermonuclear reaction rates

    E-Print Network [OSTI]

    Eduardo Bravo; Gabriel Martínez-Pinedo

    2012-04-09

    We explore the sensitivity of the nucleosynthesis due to type Ia supernovae with respect to uncertainties in nuclear reaction rates. We have adopted a standard one-dimensional delayed detonation model of the explosion of a Chandrasekhar-mass white dwarf, and have post-processed the thermodynamic trajectories of every mass-shell with a nucleosynthetic code, with increases (decreases) by a factor of ten on the rates of 1196 nuclear reactions. We have computed as well hydrodynamic models for different rates of the fusion reactions of 12C and of 16O. For selected reactions, we have recomputed the nucleosynthesis with alternative prescriptions for their rates taken from the JINA REACLIB database, and have analyzed the temperature ranges where modifications of their rates have the strongest effect on nucleosynthesis. The nucleosynthesis resulting from the Type Ia supernova models is quite robust with respect to variations of nuclear reaction rates, with the exception of the reaction of fusion of 12C nuclei. The energy of the explosion changes by less than \\sim4%. The changes in the nucleosynthesis due to the modification of the rates of fusion reactions are as well quite modest, for instance no species with a mass fraction larger than 0.02 experiences a variation of its yield larger than a factor of two. We provide the sensitivity of the yields of the most abundant species with respect to the rates of the most intense reactions with protons, neutrons, and alphas. In general, the yields of Fe-group nuclei are more robust than the yields of intermediate-mass elements. Among the charged particle reactions, the most influential on supernova nucleosynthesis are 30Si + p \\rightleftarrows 31P + {\\gamma}, 20Ne + {\\alpha} \\rightleftarrows 24Mg + {\\gamma}, and 24Mg + {\\alpha} \\rightleftarrows 27Al + p. The temperatures at which a modification of their rate has a larger impact are in the range 2 < T < 4 GK. (abridged)

  17. EVOLUTION OF POST-IMPACT REMNANT HELIUM STARS IN TYPE Ia SUPERNOVA REMNANTS WITHIN THE SINGLE-DEGENERATE SCENARIO

    SciTech Connect (OSTI)

    Pan, Kuo-Chuan; Ricker, Paul M. [Department of Astronomy, University of Illinois at Urbana-Champaign, 1002 West Green Street, Urbana, IL 61801 (United States); Taam, Ronald E., E-mail: kpan2@illinois.edu, E-mail: pmricker@illinois.edu, E-mail: r-taam@northwestern.edu [Department of Physics and Astronomy, Northwestern University, 2145 Sheridan Road, Evanston, IL 60208 (United States)

    2013-08-10

    The progenitor systems of Type Ia supernovae (SNe Ia) are still under debate. Based on recent hydrodynamics simulations, non-degenerate companions in the single-degenerate scenario (SDS) should survive the supernova (SN) impact. One way to distinguish between the SDS and the double-degenerate scenario is to search for the post-impact remnant stars (PIRSs) in SN Ia remnants. Using a technique that combines multi-dimensional hydrodynamics simulations with one-dimensional stellar evolution simulations, we have examined the post-impact evolution of helium-rich binary companions in the SDS. It is found that these helium-rich PIRSs (He PIRSs) dramatically expand and evolve to a luminous phase (L {approx} 10{sup 4} L{sub Sun }) about 10 yr after an SN explosion. Subsequently, they contract and evolve to become hot blue-subdwarf-like (sdO-like) stars by releasing gravitational energy, persisting as sdO-like stars for several million years before evolving to the helium red-giant phase. We therefore predict that a luminous OB-like star should be detectable within {approx}30 yr after the SN explosion. Thereafter, it will shrink and become an sdO-like star in the central regions of SN Ia remnants within star-forming regions for SN Ia progenitors evolved via the helium-star channel in the SDS. These He PIRSs are predicted to be rapidly rotating (v{sub rot} {approx}> 50 km s{sup -1}) and to have high spatial velocities (v{sub linear} {approx}> 500 km s{sup -1}). Furthermore, if SN remnants have diffused away and are not recognizable at a later stage, He PIRSs could be an additional source of single sdO stars and/or hypervelocity stars.

  18. The influence of ridge geometry at the ultraslow-spreading Southwest Indian Ridge (9?-25?E) : basalt composition sensitivity to variations in source and process

    E-Print Network [OSTI]

    Standish, Jared Jeffrey

    2006-01-01

    Between 90-25° E on the ultraslow-spreading Southwest Indian Ridge lie two sharply contrasting supersegments. One 630 km long supersegment erupts N-MORB that is progressively enriched in incompatible element concentrations ...

  19. Surface expression of eastern Mediterranean slab dynamics: Neogene topographic and structural evolution of the southwest margin of the Central Anatolian Plateau, Turkey

    E-Print Network [OSTI]

    Schildgen, T. F.

    he southwest margin of the Central Anatolian Plateau has experienced multiple phases of topographic growth, including the formation of localized highs prior to the Late Miocene that were later affected by wholesale uplift ...

  20. Gen. Tech. Rep. PSW-101 Berkeley, CA. Pacific Southwest Forest and Range Experiment Station, Forest Service, U.S. Department of Agriculture; 1987.

    E-Print Network [OSTI]

    without close human supervision. By the year 2000, the sensing instruments may work from radiation, tGen. Tech. Rep. PSW-101 Berkeley, CA. Pacific Southwest Forest and Range Experiment Station, Forest

  1. Site Suitability Assessment for Irrigating Urban Landscapes with Water of Elevated Salinity in the Southwest. Consolidated Final Report. Part 1. Water Quality and Plant Tolerance 

    E-Print Network [OSTI]

    Miyamoto, S.

    With increasing population and the demand for potable water, water with elevated salinity and reclaimed water are now commonly used for irrigating urban landscape in many communities in the arid Southwest. It not only saves potable water, but also...

  2. A Comparison of the Published Stellar Photometry Data in the South-West Field of the Galaxy M31 Disk

    E-Print Network [OSTI]

    D. Narbutis; R. Stonkute; V. Vansevicius

    2006-10-05

    We compare stellar photometry data in the South-West part of the M31 disk published by Magnier et al. (1992), Mochejska et al. (2001) and Massey et al. (2006) as the local photometric standards for the calibration of star cluster aperture photometry. Large magnitude and color differences between these catalogs are found. This makes one to be cautious in using these data as the local photometric standards for new photometry.

  3. ANALYZING HIGHWAY DAMAGE COSTS ATTRIBUTED TO TRUCK TRAFFIC OF PROCESSED MEAT AND RELATED INDUSTRIES IN SOUTHWEST KANSAS

    E-Print Network [OSTI]

    Liu, Chunxiao

    2007-12-03

    .................................................................................... 10 2.1 Processed Meat Industries in Southwest Kansas ............................................ 11 2.1.1 Various Stages in the Movement of Cattle.............................................. 12 2.1.2 Cattle Feeding Industry... ................................................................................................................ 57 4.1 Truck VMT for Transporting Feeder Cattle to Feed Yards............................ 62 4.1.1 Truck Travel Paths for Transporting Feeder Cattle to Feed Yards ....... 62 4.1.2 Truckloads for Transporting Feeder Cattle to Feed Yards...

  4. Drought and the 2002-2003 El Nio in the Southwest U.S. Glenn A. Tootle1

    E-Print Network [OSTI]

    Piechota, Thomas C.

    following the 11 identified El Nino events during 1923- 2002 are evaluated to determine if currentDrought and the 2002-2003 El Niño in the Southwest U.S. Glenn A. Tootle1 and Thomas C. Piechota2 1 of drought causing water shortages and low lake levels, and now an El Niño event is occurring. This study

  5. Southwest Michigan Community Action Agency Â… Weatherization Assistance Program Funds Provided by the American Recovery and Reinvestment Act of 2009

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Delicious Rank EERE:Financing Tool FitsProjectDataSecretaryDepartment7 Annual ReportSouthwest Michigan Community Action

  6. MIDWEST ISO UPDATE Sherman Elliott

    E-Print Network [OSTI]

    Tesfatsion, Leigh

    of power over the high voltage transmission system Schedule transmission service Security analysis Manage power congestion through locational marginal pricing (LMP) energy market Long term regional transmission Centralize Generation Dispatch and Outage Management · Efficiently dispatch market generation assets every 5

  7. Midwest Numerical Analysis Day 2011

    E-Print Network [OSTI]

    Describe content of page here. ... Lawson Building (Computer Science), Purdue University, ... about this conference, please join the MWNA mailing list by sending an email with the subject line "subscribe" to mwnaday-request@math.iit.edu.

  8. Midwest Numerical Analysis Day 2011

    E-Print Network [OSTI]

    ... such as binary black hole systems or black hole - neutron star dynamics. .... The scattering of acoustic and electromagnetic waves by periodic structures plays ...

  9. Evolution of the Midwest ISO

    E-Print Network [OSTI]

    Tesfatsion, Leigh

    Power · NSP/Xcel Energy (part of TRANSLink) #12;Coordination Agreement Members · Manitoba Hydro Appendix with the formation of power pools in the Northeastern U.S. (PJM, New York, New England) #12;General Utility (continued) · ISOs formed starting 1997 ­ California ISO & Power Exchange ­ PJM ­ New York ­ New England

  10. Midwest Numerical Analysis Day 2011

    E-Print Network [OSTI]

    Such methods excel in controlling “structural” information losses responsible for ... The second example demonstrates how optimization ideas enable design of .... Calculating mixed cells which produces mixed volume as a by-product is the ...

  11. Vulnerability and adaptation to severe weather events in the American southwest

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

    Boero, Riccardo; Bianchini, Laura; Pasqualini, Donatella

    2015-05-04

    Climate change can induce changes in the frequency of severe weather events representing a threat to socio-economic development. It is thus of uttermost importance to understand how the vulnerability to the weather of local communities is determined and how adaptation public policies can be effectively put in place. We focused our empirical analysis on the American Southwest. Results show that, consistently with the predictions of an investment model, economic characteristics signaling local economic growth in the near future decrease the level of vulnerability. We also show that federal governments transfers and grants neither work to support recovery from and adaptationmore »to weather events nor to distribute their costs over a broader tax base. Finally, we show that communities relying on municipal bonds to finance adaptation and recovery policies can benefit from local acknowledgment of the need for such policies and that they do not have to pay lenders a premium for the risk induced by weather events. In conclusion, our findings suggest that determinants of economic growth support lower vulnerability to the weather and increase options for financing adaptation and recovery policies, but also that only some communities are likely to benefit from those processes.« less

  12. Carbon Sequestration Atlas and Interactive Maps from the Southwest Regional Partnership on Carbon Sequestration

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

    McPherson, Brian

    In November of 2002, DOE announced a global climate change initiative involving joint government-industry partnerships working together to find sensible, low cost solutions for reducing GHG emissions. As a result, seven regional partnerships were formed; the Southwest Regional Partnership on Carbon Sequestration (SWP) is one of those. These groups are utilizing their expertise to assess sequestration technologies to capture carbon emissions, identify and evaluate appropriate storage locations, and engage a variety of stakeholders in order to increase awareness of carbon sequestration. Stakeholders in this project are made up of private industry, NGOs, the general public, and government entities. There are a total of 44 current organizations represented in the partnership including electric utilities, oil and gas companies, state governments, universities, NGOs, and tribal nations. The SWP is coordinated by New Mexico Tech and encompasses New Mexico, Arizona, Colorado, Oklahoma, Utah, and portions of Kansas, Nevada, Texas, and Wyoming. Field test sites for the region are located in New Mexico (San Juan Basin), Utah (Paradox Basin), and Texas (Permian Basin).[Taken from the SWP C02 Sequestration Atlas] The SWP makes available at this website their CO2 Sequestration Atlas and an interactive data map.

  13. Introducci'on a la Programaci'on L'ogica Posgrado en Ciencia e Ingenier'ia de la Computaci'on

    E-Print Network [OSTI]

    Velarde, Carlos

    Introducci'on a la Programaci'on L'ogica Posgrado en Ciencia e Ingenier'ia de la Computaci'on 1999­2 David Rosenblueth y Carlos Velarde Parte I: Conceptos B'asicos de la Programaci'on L'ogica 1 Hechos y resoluci'on 6 Resoluci'on en forma textual 7 Metodolog'ia de programaci'on 8 Listas, 1a parte 9 Prolog puro

  14. THE IMPACT OF TYPE Ia SUPERNOVA EXPLOSIONS ON HELIUM COMPANIONS IN THE CHANDRASEKHAR-MASS EXPLOSION SCENARIO

    SciTech Connect (OSTI)

    Liu Zhengwei; Wang, B.; Han, Z. W. [Yunnan Observatories, Chinese Academy of Sciences, Kunming 650011 (China); Pakmor, R. [Heidelberger Institut fuer Theoretische Studien, Schloss-Wolfsbrunnenweg 35, D-69118 Heidelberg (Germany); Seitenzahl, I. R.; Hillebrandt, W.; Kromer, M.; Edelmann, P.; Taubenberger, S. [Max-Planck-Institut fuer Astrophysik, Karl-Schwarzschild-Str. 1, D-85741 Garching (Germany); Roepke, F. K. [Institut fuer Theoretische Physik und Astrophysik, Universitaet Wuerzburg, Am Hubland, D-97074 Wuerzburg (Germany); Maeda, K., E-mail: zwliu@ynao.ac.cn [Kavli Institute for the Physics and Mathematics of the Universe (Kavli-IPMU), Todai Institutes for Advanced Study (TODIAS), University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8583 (Japan)

    2013-09-01

    In the version of the single-degenerate scenario of Type Ia supernovae (SNe Ia) studied here, a carbon-oxygen white dwarf explodes close to the Chandrasekhar limit after accreting material from a non-degenerate helium (He) companion star. In the present study, we employ the STELLAR GADGET code to perform three-dimensional hydrodynamical simulations of the interaction of the SN Ia ejecta with the He companion star taking into account its orbital motion and spin. It is found that only 2%-5% of the initial companion mass is stripped off from the outer layers of He companion stars due to the supernova (SN) impact. The dependence of the unbound mass (or the kick velocity) on the orbital separation can be fitted to a good approximation by a power law for a given companion model. After the SN impact, the outer layers of a He donor star are significantly enriched with heavy elements from the low-expansion-velocity tail of SN Ia ejecta. The total mass of accumulated SN-ejecta material on the companion surface reaches about {approx}> 10{sup -3} M{sub Sun} for different companion models. This enrichment with heavy elements provides a potential way to observationally identify the surviving companion star in SN remnants. Finally, by artificially adjusting the explosion energy of the W7 explosion model, we find that the total accumulation of SN ejecta on the companion surface is also dependent on the explosion energy with a power-law relation to a good approximation.

  15. PRODUCTION OF THE p-PROCESS NUCLEI IN THE CARBON-DEFLAGRATION MODEL FOR TYPE Ia SUPERNOVAE

    SciTech Connect (OSTI)

    Kusakabe, Motohiko; Iwamoto, Nobuyuki; Nomoto, Ken'ichi E-mail: iwamoto.nobuyuki@jaea.go.jp

    2011-01-01

    We calculate the nucleosynthesis of proton-rich isotopes in the carbon-deflagration model for Type Ia supernovae (SNe Ia). The seed abundances are obtained by calculating the s-process nucleosynthesis that is expected to occur in the repeating helium shell flashes on the carbon-oxygen (CO) white dwarf (WD) during mass accretion from a binary companion. When the deflagration wave passes through the outer layer of the CO WD, p-nuclei are produced by photodisintegration reactions on s-nuclei in a region where the peak temperature ranges from 1.9 to 3.6 x 10{sup 9} K. We confirm the sensitivity of the p-process on the initial distribution of s-nuclei. We show that the initial C/O ratio in the WD does not affect much the yield of p-nuclei. On the other hand, the abundance of {sup 22}Ne left after s-processing has a large influence on the p-process via the {sup 22}Ne({alpha},n) reaction. We find that about 50% of p-nuclides are co-produced when normalized to their solar abundances in all adopted cases of seed distribution. Mo and Ru, which are largely underproduced in Type II supernovae (SNe II), are produced more than in SNe II although they are underproduced with respect to the yield levels of other p-nuclides. The ratios between p-nuclei and iron in the ejecta are larger than the solar ratios by a factor of 1.2. We also compare the yields of oxygen, iron, and p-nuclides in SNe Ia and SNe II and suggest that SNe Ia could make a larger contribution than SNe II to the solar system content of p-nuclei.

  16. Spectroscopic Properties of Star-Forming Host Galaxies and Type Ia Supernova Hubble Residuals in a Nearly Unbiased Sample

    SciTech Connect (OSTI)

    D'Andrea, Chris B.; et al.

    2011-12-20

    We examine the correlation between supernova host galaxy properties and their residuals on the Hubble diagram. We use supernovae discovered during the Sloan Digital Sky Survey II - Supernova Survey, and focus on objects at a redshift of z < 0.15, where the selection effects of the survey are known to yield a complete Type Ia supernova sample. To minimize the bias in our analysis with respect to measured host-galaxy properties, spectra were obtained for nearly all hosts, spanning a range in magnitude of -23 < M_r < -17. In contrast to previous works that use photometric estimates of host mass as a proxy for global metallicity, we analyze host-galaxy spectra to obtain gas-phase metallicities and star-formation rates from host galaxies with active star formation. From a final sample of ~ 40 emission-line galaxies, we find that light-curve corrected Type Ia supernovae are ~ 0.1 magnitudes brighter in high-metallicity hosts than in low-metallicity hosts. We also find a significant (> 3{\\sigma}) correlation between the Hubble residuals of Type Ia supernovae and the specific star-formation rate of the host galaxy. We comment on the importance of supernova/host-galaxy correlations as a source of systematic bias in future deep supernova surveys.

  17. Optical and Infrared Photometry of the Nearby Type Ia Supernovae 1999ee, 2000bh, 2000ca, and 2001ba

    E-Print Network [OSTI]

    Kevin Krisciunas; Mark M. Phillips; Nicholas B. Suntzeff; S. E. Persson; Mario Hamuy; Roberto Antezana; Pablo Candia; Alejandro Clocchiatti; Darren L. DePoy; Lisa M. Germany; Luis Gonzalez; Sergio Gonzalez; Wojtek Krzeminski; Jose Maza; Peter E. Nugent; Yulei Qiu; Armin Rest; Miguel Roth; Maximilian Stritzinger; L. -G. Strolger; Ian Thompson; T. B. Williams; Marina Wischnjewsky

    2003-11-18

    We present near infrared photometry of the Type Ia supernova 1999ee; also, optical and infrared photometry of the Type Ia SNe 2000bh, 2000ca, and 2001ba. For SNe 1999ee and 2000bh we present the first-ever SN photometry at 1.035 microns (the Y-band). We present K-corrections which transform the infrared photometry in the observer's frame to the supernova rest frame. Using our infrared K-corrections and stretch factors derived from optical photometry, we construct JHK templates which can be used to determine the apparent magnitudes at maximum if one has some data in the window -12 to +10 d with respect to T(B_max). Following up previous work on the uniformity of V minus IR loci of Type Ia supernovae of mid-range decline rates, we present unreddened loci for slow decliners. We also discuss evidence for a continuous change of color at a given epoch as a function of decline rate.

  18. Constraints on the progenitor system of the type Ia supernova 2014J from pre-explosion Hubble space telescope imaging

    SciTech Connect (OSTI)

    Kelly, Patrick L.; Fox, Ori D.; Filippenko, Alexei V.; Shen, Ken J.; Zheng, WeiKang; Graham, Melissa L.; Tucker, Brad E. [Department of Astronomy, University of California, Berkeley, CA 94720-3411 (United States); Cenko, S. Bradley [NASA/Goddard Space Flight Center, Code 662, Greenbelt, MD 20771 (United States); Prato, Lisa [Lowell Observatory, 1400 West Mars Hill Road, Flagstaff, AZ 86001 (United States); Schaefer, Gail, E-mail: pkelly@astro.berkeley.edu [The CHARA Array of Georgia State University, Mount Wilson Observatory, Mount Wilson, CA 91023 (United States)

    2014-07-20

    We constrain the properties of the progenitor system of the highly reddened Type Ia supernova (SN Ia) 2014J in Messier 82 (M82; d ? 3.5 Mpc). We determine the supernova (SN) location using Keck-II K-band adaptive optics images, and we find no evidence for flux from a progenitor system in pre-explosion near-ultraviolet through near-infrared Hubble Space Telescope (HST) images. Our upper limits exclude systems having a bright red giant companion, including symbiotic novae with luminosities comparable to that of RS Ophiuchi. While the flux constraints are also inconsistent with predictions for comparatively cool He-donor systems (T ? 35,000 K), we cannot preclude a system similar to V445 Puppis. The progenitor constraints are robust across a wide range of R{sub V} and A{sub V} values, but significantly greater values than those inferred from the SN light curve and spectrum would yield proportionally brighter luminosity limits. The comparatively faint flux expected from a binary progenitor system consisting of white dwarf stars would not have been detected in the pre-explosion HST imaging. Infrared HST exposures yield more stringent constraints on the luminosities of very cool (T < 3000 K) companion stars than was possible in the case of SN Ia 2011fe.

  19. Metabolomic profiling of the nectars of Aquilegia pubescens and <i>A. Canadensis

    SciTech Connect (OSTI)

    Noutsos, Christos; Perera, Ann M.; Nikolau, Basil J.; Seaver, Samuel M. D.; Ware, Doreen H.; Motta, Andrea

    2015-05-01

    To date, variation in nectar chemistry of flowering plants has not been studied in detail. Such variation exerts considerable influence on pollinator–plant interactions, as well as on flower traits that play important roles in the selection of a plant for visitation by specific pollinators. Over the past 60 years the Aquilegia genus has been used as a key model for speciation studies. In this study, we defined the metabolomic profiles of flower samples of two Aquilegia species, <i>A. Canadensis and <i>A. pubescens. We identified a total of 75 metabolites that were classified into six main categories: organic acids, fatty acids, amino acids, esters, sugars, and unknowns. The mean abundances of 25 of these metabolites were significantly different between the two species, providing insights into interspecies variation in floral chemistry. Using the PlantSEED biochemistry database, we found that the majority of these metabolites are involved in biosynthetic pathways. Finally, we explored the annotated genome of <i>A. coerulea, using the PlantSEED pipeline and reconstructed the metabolic network of Aquilegia. This network, which contains the metabolic pathways involved in generating the observed chemical variation, is now publicly available from the DOE Systems Biology Knowledge Base (KBase; http://kbase.us).

  20. Two Type Ia Supernovae at Redshift ~2 : Improved Classification and Redshift Determination with Medium-band Infrared Imaging

    E-Print Network [OSTI]

    Rodney, Steven A; Scolnic, Daniel M; Jones, David O; Hemmati, Shoubaneh; Molino, Alberto; McCully, Curtis; Mobasher, Bahram; Strolger, Louis-Gregory; Graur, Or; Hayden, Brian; Casertano, Stefano

    2015-01-01

    We present two supernovae (SNe) discovered with the Hubble Space Telescope (HST) in the Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey (CANDELS), an HST multi-cycle treasury program. We classify both objects as Type Ia SNe and find redshifts of z = 1.80+-0.02 and 2.26 +0.02 -0.10, the latter of which is the highest redshift Type Ia SN yet seen. Using light curve fitting we determine luminosity distances and find that both objects are consistent with a standard Lambda-CDM cosmological model. These SNe were observed using the HST Wide Field Camera 3 infrared detector (WFC3-IR), with imaging in both wide- and medium-band filters. We demonstrate that the classification and redshift estimates are significantly improved by the inclusion of single-epoch medium-band observations. This medium-band imaging approximates a very low resolution spectrum (lambda/delta lambda ~ 100) which can isolate broad spectral absorption features that differentiate Type Ia SNe from their most common core collapse cousins...

  1. Final Evolution and Delayed Explosions of Spinning White Dwarfs in Single Degenerate Models for Type Ia Supernovae

    E-Print Network [OSTI]

    Benvenuto, Omar G; Kitamura, Hikaru; Hachisu, Izumi

    2015-01-01

    We study the occurrence of delayed SNe~Ia in the single degenerate (SD) scenario. We assume that a massive carbon-oxygen (CO) white dwarf (WD) accretes matter coming from a companion star, making it to spin at the critical rate. We assume uniform rotation due to magnetic field coupling. The carbon ignition mass for non-rotating WDs is M_{ig}^{NR} \\approx 1.38 M_{\\odot}; while for the case of uniformly rotating WDs it is a few percent larger (M_{ig}^{R} \\approx 1.43 M_{\\odot}). When accretion rate decreases, the WD begins to lose angular momentum, shrinks, and spins up; however, it does not overflow its critical rotation rate, avoiding mass shedding. Thus, angular momentum losses can lead the CO WD interior to compression and carbon ignition, which would induce an SN~Ia. The delay, largely due to the angular momentum losses timescale, may be large enough to allow the companion star to evolve to a He WD, becoming undetectable at the moment of explosion. This scenario supports the occurrence of delayed SNe~Ia if...

  2. Radiogenic p-isotopes from type Ia supernova, nuclear physics uncertainties, and galactic chemical evolution compared with values in primitive meteorites

    SciTech Connect (OSTI)

    Travaglio, C.; Gallino, R.; Rauscher, T.; Dauphas, N.; Röpke, F. K.; Hillebrandt, W. E-mail: claudia.travaglio@b2fh.org

    2014-11-10

    The nucleosynthesis of proton-rich isotopes is calculated for multi-dimensional Chandrasekhar-mass models of Type Ia supernovae (SNe Ia) with different metallicities. The predicted abundances of the short-lived radioactive isotopes {sup 92}Nb, {sup 97,} {sup 98}Tc, and {sup 146}Sm are given in this framework. The abundance seeds are obtained by calculating s-process nucleosynthesis in the material accreted onto a carbon-oxygen white dwarf from a binary companion. A fine grid of s-seeds at different metallicities and {sup 13}C-pocket efficiencies is considered. A galactic chemical evolution model is used to predict the contribution of SN Ia to the solar system p-nuclei composition measured in meteorites. Nuclear physics uncertainties are critical to determine the role of SNe Ia in the production of {sup 92}Nb and {sup 146}Sm. We find that, if standard Chandrasekhar-mass SNe Ia are at least 50% of all SN Ia, they are strong candidates for reproducing the radiogenic p-process signature observed in meteorites.

  3. Tangled Up in Knots: Structures of Inactivated Forms of E. coli Class Ia Ribonucleotide Reductase

    SciTech Connect (OSTI)

    Zimanyi, Christina M.; Ando, Nozomi; Brignole, Edward J.; Asturias, Francisco J.; Stubbe, JoAnne; Drennan, Catherine L. (MIT); (Scripps)

    2012-10-23

    Ribonucleotide reductases (RNRs) provide the precursors for DNA biosynthesis and repair and are successful targets for anticancer drugs such as clofarabine and gemcitabine. Recently, we reported that dATP inhibits E. coli class Ia RNR by driving formation of RNR subunits into {alpha}{sub 4}{beta}{sub 4} rings. Here, we present the first X-ray structure of a gemcitabine-inhibited E. coli RNR and show that the previously described {alpha}{sub 4}{beta}{sub 4} rings can interlock to form an unprecedented ({alpha}{sub 4}{beta}{sub 4}){sub 2} megacomplex. This complex is also seen in a higher-resolution dATP-inhibited RNR structure presented here, which employs a distinct crystal lattice from that observed in the gemcitabine-inhibited case. With few reported examples of protein catenanes, we use data from small-angle X-ray scattering and electron microscopy to both understand the solution conditions that contribute to concatenation in RNRs as well as present a mechanism for the formation of these unusual structures.

  4. Color dispersion and Milky-Way-like reddening among type Ia supernovae

    SciTech Connect (OSTI)

    Scolnic, Daniel M.; Riess, Adam G.; Rodney, Steven A.; Brout, Dillon J.; Jones, David O. [Department of Physics and Astronomy, Johns Hopkins University, 3400 North Charles Street, Baltimore, MD 21218 (United States); Foley, Ryan J. [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Rest, Armin [Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218 (United States)

    2014-01-01

    Past analyses of Type Ia supernovae have identified an irreducible scatter of 5%-10% in distance, widely attributed to an intrinsic dispersion in luminosity. Another equally valid source of this scatter is intrinsic dispersion in color. Misidentification of the true source of this scatter can bias both the retrieved color-luminosity relation and cosmological parameter measurements. The size of this bias depends on the magnitude of the intrinsic color dispersion relative to the distribution of colors that correlate with distance. We produce a realistic simulation of a misattribution of intrinsic scatter and find a negative bias in the recovered color-luminosity relation, ?, of ?? ? –1.0 (?33%) and a positive bias in the equation of state parameter, w, of ?w ? +0.04 (?4%). We re-analyze current published datasets with the assumption that the distance scatter is predominantly the result of color. Unlike previous analyses, we find that the data are consistent with a Milky-Way-like reddening law (R{sub V} = 3.1) and that a Milky-Way dust model better predicts the asymmetric color-luminosity trends than the conventional luminosity scatter hypothesis. We also determine that accounting for color variation reduces the correlation between various host galaxy properties and Hubble residuals by ?20%.

  5. A Test of Tully-Fisher Distance Estimates Using Cepheids and Type Ia Supernovae

    E-Print Network [OSTI]

    T. Shanks

    1999-01-24

    We update and extend the results of Shanks (1997, MNRAS, 290, L77) by making a direct test of Tully-Fisher distance estimates to thirteen spiral galaxies with HST Cepheid distances and to ten spiral galaxies with Type Ia supernova (SNIa) distances. The results show that the Tully-Fisher distance moduli are too short with respect to the Cepheid distances by 0.46+-0.11mag and too short with respect to the SNIa distances by 0.49+-0.18mag. Combining the HST Cepheid and the best SNIa data suggests that, overall, previous Tully-Fisher distances at v~1000 kms-1 were too short by 0.43+-0.09mag, a result which is significant at the 4.6 sigma level. These data therefore indicate that previous Tully-Fisher distances should be revised upwards by 22+-5% implying, for example, a Virgo distance of 19.0+-1.8Mpc. The value of Ho from Tully-Fisher estimates is correspondingly revised downwards from Ho=84+-10kms-1Mpc-1 to Ho=69+-8kms-1Mpc-1. There is evidence that the Tully-Fisher relation at large distances is affected by Malmquist bias. In this case, we argue that Ho<50kms-1Mpc-1 cannot be ruled out by Tully-Fisher considerations.

  6. On Iron Enrichment, Star Formation, and Type Ia Supernovae in Galaxy Clusters

    E-Print Network [OSTI]

    Michael Loewenstein

    2006-05-04

    The nature of star formation and Type Ia supernovae (SNIa) in galaxies in the field and in rich galaxy clusters are contrasted by juxtaposing the build-up of heavy metals in the universe inferred from observed star formation and supernovae rate histories with data on the evolution of Fe abundances in the intracluster medium (ICM). Models for the chemical evolution of Fe in these environments are constructed, subject to observational constraints, for this purpose. While models with a mean delay for SNIa of 3 Gyr and standard initial mass function (IMF) are consistent with observations in the field, cluster Fe enrichment immediately tracks a rapid, top-heavy phase of star formation -- although transport of Fe into the ICM may be more prolonged and star formation likely continues to redshifts formation mode. Star formation is >3 times more efficient in rich clusters than in the field, mitigating the overcooling problem in numerical cluster simulations. Both the fraction of baryons cycled through stars, and the fraction of the total present-day stellar mass in the form of stellar remnants, are substantially greater in clusters than in the field.

  7. Revised photometry and color distribution of Type Ia supernovae observed at Asiago in the seventies

    E-Print Network [OSTI]

    F. Patat; R. Barbon; E. Cappellaro M. Turatto

    1996-05-29

    Following recent claims regarding possible errors in the photometry of SNe carried out at Asiago observatory during the 70's, which produced very blue $(B-V)$ color at maximum for some objects, we present the result of new CCD photometry of the sequences around 16 type Ia supernovae. Except for a few cases, e.g. SN1970J and SN1972J for which a large zero point error has been found, the new data show that the old Asiago observations have been carried out properly and that their accuracy was comparable to that expected for a photometry based on photographic transfers. This result is also substantiated by comparison with the re-calibration of some Asiago sequences made photo-electrically by Tsvetkov. New light curves of the SNe have been determined and B magnitudes and (B-V) colors at light peak derived. With the new data the color distribution of the SNe studied here becomes narrower and moves to the red by only 0.06 mag, showing no more very blue objects except for one, still uncertain, case. As far as the use of SNIa as standard candles is concerned, we show that the utilization of all SNe in the M$_B$ vs. (B-V)$^{max}_0$ plane reduces the uncertainties due to the photometry.

  8. Evidence for Microvariability in the Optical Light Curve of the Type Ia SN 2014J

    E-Print Network [OSTI]

    Bonanos, A Z

    2015-01-01

    We present results of high-cadence monitoring of the optical light curve of the nearby, Type Ia SN 2014J in M82 using the 2.3m Aristarchos telescope. $B$ and $V$-band photometry on days 15-18 after $t_{max}(B)$, obtained with a cadence of 2 min per band, reveals evidence for variability at the 0.02-0.05 mag level on timescales of 15-60 min on all four nights. The decline slope was measured to be steeper in the $B$-band than in $V$-band, and to steadily decrease in both bands from 0.15 mag/day (night 1) to 0.04 mag/day (night 4) in V and from 0.19 mag/day (night 1) to 0.06 mag/day (night 4) in B, corresponding to the onset of the secondary maximum. We propose that microvariability could be due to one or a combination of the following scenarios: the clumpiness of the ejecta, their interaction with circumstellar material, the asymmetry of the explosion, or the mechanism causing the secondary maximum in the near-infrared light curve. We encourage the community to undertake high-cadence monitoring of future, nearb...

  9. Accelerating universe from gravitational leakage into extra dimensions: confrontation with SNeIa

    E-Print Network [OSTI]

    Zong-Hong Zhu; Jailson S. Alcaniz

    2004-11-01

    There is mounting observational evidence that the expansion of our universe is undergoing an acceleration. A dark energy component has usually been invoked as the most feasible mechanism for the acceleration. However, it is desirable to explore alternative possibilities motivated by particle physics before adopting such an untested entity. In this work, we focus our attention on an acceleration mechanism: one arising from gravitational leakage into extra dimensions. We confront this scenario with high-$z$ type Ia supernovae compiled by Tonry et al. (2003) and recent measurements of the X-ray gas mass fractions in clusters of galaxies published by Allen et al. (2002,2003). A combination of the two databases gives at a 99% confidence level that $\\Omega_m=0.29^{+0.04}_{-0.02}$, $\\Omega_{rc}=0.21^{+0.08}_{-0.08}$, and $\\Omega_k=-0.36^{+0.31}_{-0.35}$, indicating a closed universe. We then constrain the model using the test of the turnaround redshift, $z_{q=0}$, at which the universe switches from deceleration to acceleration. We show that, in order to explain that acceleration happened earlier than $z_{q=0} = 0.6$ within the framework of gravitational leakage into extra dimensions, a low matter density, $\\Omega_m < 0.27$, or a closed universe is necessary.

  10. Type Ia Supernovae: Can Coriolis force break the symmetry of the gravitational confined detonation explosion mechanism?

    E-Print Network [OSTI]

    García-Senz, D; Domínguez, I; Thielemann, F K

    2015-01-01

    Nowadays the number of models aimed at explaining the Type Ia supernova phenomenon is high and discriminating between them is a must-do. In this work we explore the influence of rotation in the evolution of the nuclear flame which drives the explosion in the so called gravitational confined detonation models. Assuming that the flame starts in a point-like region slightly above the center of the white dwarf (WD) and adding a moderate amount of angular velocity to the star we follow the evolution of the deflagration using a smoothed particle hydrodynamics code. We find that the results are very dependent on the angle between the rotational axis and the line connecting the initial bubble of burned material with the center of the white dwarf at the moment of the ignition. The impact of rotation is larger for angles close to 90{\\deg} because the Coriolis force on a floating element of fluid is maximum, and its principal effect is to break the symmetry of the deflagration. Such symmetry breaking weakens the converg...

  11. The Internal Shear of Type Ia Supernova Progenitors During Accretion and Simmering

    E-Print Network [OSTI]

    Anthony L. Piro

    2008-01-07

    A white dwarf (WD) gains substantial angular momentum during the accretion process that grows it toward a Chandrasekhar mass. It is therefore expected to be quickly rotating when it ignites as a Type Ia supernova. The thermal and shearing profile are important for subsequent flame propagation. We highlight processes that could affect the WD shear, during accretion as well as during the ~1000 years of pre-explosive simmering. Baroclinic instabilities and/or the shear growth of small magnetic fields provide sufficient torque to bring the WD very close to solid body rotation during accretion. The lack of significant shear makes it difficult to grow a WD substantially past the typical Chandrasekhar mass. Once carbon ignites, a convective region spreads from the WD's center. This phase occurs regardless of progenitor scenario, and therefore it is of great interest for understanding how the WD interior is prepared before the explosive burning begins. We summarize some of the key properties of the convective region, which includes demonstrating that the mass enclosed by convection at any given time depends most sensitively on a single parameter that can be expressed as either the ratio of temperatures or densities at the top and bottom of the convection zone. At low Rossby numbers the redistribution of angular momentum by convection may result in significant shearing at the convective/non-convective boundary.

  12. SN1994D in NGC4526: a normally bright type Ia supernova

    E-Print Network [OSTI]

    Georg Drenkhahn; Tom Richtler

    1999-09-07

    SN1994D of type Ia has been suspected not to fit into the relation between decline rate, colour, and brightness. However, an individual distance of its host galaxy, NGC4526, other than that of the Virgo cluster, has not yet been published. We determined the distance by the method of globular cluster luminosity functions on the basis of HST archive data. A maximum-likelihood fit returns apparent turn-over magnitudes of 23.16+-0.16mag in V and 21.96+-0.09mag in I. The corresponding distance modulus is 30.4+-0.3mag, where the error reflects our estimation of the absolute distance scale. The absolute magnitudes (not corrected for decline rate and colour) are -18.67+-0.30mag, -18.62+-0.30mag, and -18.40+-0.30mag for B, V, and I, respectively. The corrected magnitudes are -18.69+-0.31mag, -18.69+-0.31mag, and -18.44+-0.31mag. Compared with other supernovae with reliably determined distances, SN1994D fits within the errors. It is therefore not a counter-example against a uniform decline-rate-colour-brightness relation.

  13. Gamma rays from a supernova of type Ia: SN2014J

    E-Print Network [OSTI]

    Diehl, Roland

    2015-01-01

    SN2014J is the closest supernova of type Ia that occured in the last 40 years. This provides an opportunity for unprecedented observational detail and coverage in many astronomical bands, which will help to better understand the still unknown astrophysics of these supernovae. For the first time, such an event occurs sufficiently nearby so that also gamma rays are able to contribute to such investigations. This is important, as the primary source of the supernova light is the radioactive energy from about 0.5 M$_\\odot$ of $^{56}$Ni produced in the explosion, and the gamma rays associated with this decay make the supernova shine for months. The INTEGRAL gamma-ray observatory of ESA has followed the supernova emission for almost 5 months. The characteristic gamma ray lines from the $^{56}$Ni decay chain through $^{56}$Co to $^{56}$Fe have been measured. We discuss these observations, and the implications of the measured gamma-ray line characteristics as they evolve.

  14. 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.

  15. DOE: Integrating Southwest Power Pool Wind Energy into Southeast Electricity Markets

    SciTech Connect (OSTI)

    Brooks, Daniel, EPRI; Tuohy, Aidan, EPRI; Deb, Sidart, LCG Consulting; Jampani, Srinivas, LCG Consulting; Kirby, Brendan, Consultant; King, Jack, Consultant

    2011-11-29

    Wind power development in the United States is outpacing previous estimates for many regions, particularly those with good wind resources. The pace of wind power deployment may soon outstrip regional capabilities to provide transmission and integration services to achieve the most economic power system operation. Conversely, regions such as the Southeastern United States do not have good wind resources and will have difficulty meeting proposed federal Renewable Portfolio Standards with local supply. There is a growing need to explore innovative solutions for collaborating between regions to achieve the least cost solution for meeting such a renewable energy mandate. The DOE-funded project 'Integrating Southwest Power Pool Wind Energy into Southeast Electricity Markets' aims to evaluate the benefits of coordination of scheduling and balancing for Southwest Power Pool (SPP) wind transfers to Southeastern Electric Reliability Council (SERC) Balancing Authorities (BAs). The primary objective of this project is to analyze the benefits of different balancing approaches with increasing levels of inter-regional cooperation. Scenarios were defined, modeled and investigated to address production variability and uncertainty and the associated balancing of large quantities of wind power in SPP and delivery to energy markets in the southern regions of the SERC. The primary analysis of the project is based on unit commitment (UC) and economic dispatch (ED) simulations of the SPP-SERC regions as modeled for the year 2022. The UC/ED models utilized for the project were developed through extensive consultation with the project utility partners, to ensure the various regions and operational practices are represented as accurately as possible realizing that all such future scenario models are quite uncertain. SPP, Entergy, Oglethorpe Power Company (OPC), Southern Company, and the Tennessee Valley Authority (TVA) actively participated in the project providing input data for the models and review of simulation results and conclusions. While other SERC utility systems are modeled, the listed SERC utilities were explicitly included as active participants in the project due to the size of their load and relative proximity to SPP for importing wind energy. The analysis aspects of the project comprised 4 primary tasks: (1) Development of SCUC/SCED model of the SPP-SERC footprint for the year 2022 with only 7 GW of installed wind capacity in SPP for internal SPP consumption with no intended wind exports to SERC. This model is referred to as the 'Non-RES' model as it does not reflect the need for the SPP or SERC BAs to meet a federal Renewable Energy Standard (RES). (2) Analysis of hourly-resolution simulation results of the Non-RES model for the year 2022 to provide project stakeholders with confidence in the model and analytical framework for a scenario that is similar to the existing system and more easily evaluated than the high-wind transfer scenarios that are analyzed subsequently. (3) Development of SCUC/SCED model of the SPP-SERC footprint for the year 2022 with sufficient installed wind capacity in SPP (approximately 48 GW) for both SPP and the participating SERC BAs to meet an RES of 20% energy. This model is referred to as the 'High-Wind Transfer' model with several different scenarios represented. The development of the High-Wind Transfer model not only included identification and allocation of SPP wind to individual SERC BAs, but also included the evaluation of various methods to allow the model to export the SPP wind to SERC without developing an actual transmission plan to support the transfers. (4) Analysis of hourly-resolution simulation results of several different High-Wind Transfer model scenarios for the year 2022 to determine balancing costs and potential benefits of collaboration among SPP and SERC BAs to provide the required balancing.

  16. The deflagration stage of Chandrasekhar mass models for type Ia supernovae. I. Early evolution

    SciTech Connect (OSTI)

    Malone, C. M.; Woosley, S. E.; Dong, S. [Department of Astronomy and Astrophysics, The University of California, Santa Cruz, Santa Cruz, CA 95064 (United States); Nonaka, A.; Almgren, A. S.; Bell, J. B. [Center for Computational Sciences and Engineering, Lawrence Berkeley National Laboratory, Berkeley, CA 94720 (United States); Zingale, M. [Department of Physics and Astronomy, Stony Brook University, Stony Brook, NY 11794 (United States)

    2014-02-10

    We present high-resolution, full-star simulations of the post-ignition phase of Type Ia supernovae using the compressible hydrodynamics code Castro. Initial conditions, including the turbulent velocity field and ignition site, are imported directly from a simulation of the last few hours of presupernova convection using a low Mach number code, Maestro. Adaptive mesh refinement allows the initial burning front to be modeled with an effective resolution of 36,864{sup 3} zones (136 m zone{sup –1}). The initial rise and expansion of the deflagration front are tracked until burning reaches the star's edge and the role of the background turbulence on the flame is investigated. The effect of artificially moving the ignition location closer to the star's center is explored. The degree to which turbulence affects the burning front decreases with increasing ignition radius since the buoyancy force is stronger at larger radii. Even central ignition—in the presence of a background convective flow field—is rapidly carried off-center as the flame is carried by the flow field. We compare our results to analytic models for burning thermals, and find that they reproduce the general trends of the bubble's size and mass, but underpredict the amount of buoyant acceleration due to simplifying assumptions of the bubble's properties. Overall, we find that the amount of mass that burns prior to flame break out is small, consistent with a gravitationally confined detonation' occurring at a later epoch, but additional burning will occur following breakout that may modify this conclusion.

  17. Reconciliation of the Surface Brightness Fluctuations and Type Ia Supernovae Distance Scales

    E-Print Network [OSTI]

    Edward A. Ajhar; John L. Tonry; John P. Blakeslee; Adam G. Riess; Brian P. Schmidt

    2001-05-21

    We present Hubble Space Telescope measurements of surface brightness fluctuations (SBF) distances to early-type galaxies that have hosted Type Ia supernovae (SNIa). The agreement in the relative SBF and SNIa multicolor light curve shape and delta-m_15 distances is excellent. There is no systematic scale error with distance, and previous work has shown that SBF and SNIa give consistent ties to the Hubble flow. However, we confirm a systematic offset of about 0.25 mag in the distance zero points of the two methods, and we trace this offset to their respective Cepheid calibrations. SBF has in the past been calibrated with Cepheid distances from the H_0 Key Project team, while SNIa have been calibrated with Cepheid distances from the team composed of Sandage, Saha, and collaborators. When the two methods are calibrated in a consistent way, their distances are in superb agreement. Until the conflict over the ``long'' and ``short'' extragalactic Cepheid distances among many galaxies is resolved, we cannot definitively constrain the Hubble constant to better than about 10%, even leaving aside the additional uncertainty in the distance to the Large Magellanic Cloud, common to both Cepheid scales. However, recent theoretical SBF predictions from stellar population models favor the Key Project Cepheid scale, while the theoretical SNIa calibration lies between the long and short scales. In addition, while the current SBF distance to M31/M32 is in good agreement with the RR Lyrae and red giant branch distances, calibrating SBF with the longer Cepheid scale would introduce a 0.3 mag offset with respect to the RR Lyrae scale.

  18. Persistent C II absorption in the normal type Ia supernova 2002fk

    SciTech Connect (OSTI)

    Cartier, Régis; Zelaya, Paula [Millennium Institute of Astrophysics, Casilla 36-D, Santiago (Chile); Hamuy, Mario; Maza, José; González, Luis; Huerta, Leonor [Departamento de Astronomía, Universidad de Chile, Casilla 36-D, Santiago (Chile); Pignata, Giuliano [Departamento Ciencias Fisicas, Universidad Andres Bello, Av. República 252, Santiago (Chile); Förster, Francisco [Center for Mathematical Modelling, Universidad de Chile, Avenida Blanco Encalada 2120, Piso 7, Santiago (Chile); Folatelli, Gaston [Institute for the Physics and Mathematics of the Universe (IPMU), University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8583 (Japan); Phillips, Mark M.; Morrell, Nidia; Contreras, Carlos; Roth, Miguel; González, Sergio [Carnegie Institution of Washington, Las Campanas Observatory, Colina el Pino s/n, Casilla 601 (Chile); Krisciunas, Kevin; Suntzeff, Nicholas B. [Department of Physics and Astronomy, Texas A and M University, 4242 TAMU, College Station, TX 77843 (United States); Clocchiatti, Alejandro [Departamento de Astronomía y Astrofísica, Pontificia Universidad Católica de Chile, Casilla 306, Santiago (Chile); Coppi, Paolo [Department of Astronomy, Yale University, New Haven, CT 06520-8101 (United States); Koviak, Kathleen, E-mail: rcartier@das.uchile.cl [Carnegie Institution of Washington, 813 Santa Barbara Street, Pasadena, CA 911901 (United States)

    2014-07-01

    We present well-sampled UBVRIJHK photometry of SN 2002fk starting 12 days before maximum light through 122 days after peak brightness, along with a series of 15 optical spectra from –4 to +95 days since maximum. Our observations show the presence of C II lines in the early-time spectra of SN 2002fk, expanding at 11,000 km s{sup –1} and persisting until 8 days past maximum light with a velocity of ?9000 km s{sup –1}. SN 2002fk is characterized by a small velocity gradient of v-dot {sub Si} {sub II}=26 km s{sup –1} day{sup –1}, possibly caused by an off-center explosion with the ignition region oriented toward the observer. The connection between the viewing angle of an off-center explosion and the presence of C II in the early-time spectrum suggests that the observation of C II could be also due to a viewing angle effect. Adopting the Cepheid distance to NGC 1309 we provide the first H {sub 0} value based on near-infrared (near-IR) measurements of a Type Ia supernova (SN) between 63.0 ± 0.8 (±3.4 systematic) and 66.7 ± 1.0 (±3.5 systematic) km s{sup –1} Mpc{sup –1}, depending on the absolute magnitude/decline rate relationship adopted. It appears that the near-IR yields somewhat lower (6%-9%) H {sub 0} values than the optical. It is essential to further examine this issue by (1) expanding the sample of high-quality near-IR light curves of SNe in the Hubble flow, and (2) increasing the number of nearby SNe with near-IR SN light curves and precise Cepheid distances, which affords the promise to deliver a more precise determination of H {sub 0}.

  19. Systematic uncertainties associated with the cosmological analysis of the first Pan-STARRS1 type Ia supernova sample

    SciTech Connect (OSTI)

    Scolnic, D.; Riess, A.; Brout, D.; Rodney, S. [Department of Physics and Astronomy, Johns Hopkins University, 3400 North Charles Street, Baltimore, MD 21218 (United States); Rest, A. [Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218 (United States); Huber, M. E.; Tonry, J. L. [Institute for Astronomy, University of Hawaii, 2680 Woodlawn Drive, Honolulu, HI 96822 (United States); Foley, R. J.; Chornock, R.; Berger, E.; Soderberg, A. M.; Stubbs, C. W.; Kirshner, R. P.; Challis, P.; Czekala, I.; Drout, M. [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Narayan, G. [Department of Physics, Harvard University, 17 Oxford Street, Cambridge, MA 02138 (United States); Smartt, S. J.; Botticella, M. T. [Astrophysics Research Centre, School of Mathematics and Physics, Queens University Belfast, Belfast BT7 1NN (United Kingdom); Schlafly, E. [Max Planck Institute for Astronomy, Konigstuhl 17, D-69117 Heidelberg (Germany); and others

    2014-11-01

    We probe the systematic uncertainties from the 113 Type Ia supernovae (SN Ia) in the Pan-STARRS1 (PS1) sample along with 197 SN Ia from a combination of low-redshift surveys. The companion paper by Rest et al. describes the photometric measurements and cosmological inferences from the PS1 sample. The largest systematic uncertainty stems from the photometric calibration of the PS1 and low-z samples. We increase the sample of observed Calspec standards from 7 to 10 used to define the PS1 calibration system. The PS1 and SDSS-II calibration systems are compared and discrepancies up to ?0.02 mag are recovered. We find uncertainties in the proper way to treat intrinsic colors and reddening produce differences in the recovered value of w up to 3%. We estimate masses of host galaxies of PS1 supernovae and detect an insignificant difference in distance residuals of the full sample of 0.037 ± 0.031 mag for host galaxies with high and low masses. Assuming flatness and including systematic uncertainties in our analysis of only SNe measurements, we find w =?1.120{sub ?0.206}{sup +0.360}(Stat){sub ?0.291}{sup +0.269}(Sys). With additional constraints from Baryon acoustic oscillation, cosmic microwave background (CMB) (Planck) and H {sub 0} measurements, we find w=?1.166{sub ?0.069}{sup +0.072} and ?{sub m}=0.280{sub ?0.012}{sup +0.013} (statistical and systematic errors added in quadrature). The significance of the inconsistency with w = –1 depends on whether we use Planck or Wilkinson Microwave Anisotropy Probe measurements of the CMB: w{sub BAO+H0+SN+WMAP}=?1.124{sub ?0.065}{sup +0.083}.

  20. Hubble Space Telescope spectra of the type Ia supernova SN 2011fe: A low-energy delayed detonation of a white dwarf with Zsolar

    E-Print Network [OSTI]

    Mazzali, Paolo; Hachinger, Stephan; Ellis, Richard; Nugent, Peter E; Howell, D Andrew; Gal-Yam, Avishay; Maguire, Kate; Cooke, Jeff; Thomas, Rollin

    2013-01-01

    Hubble Space Telescope spectroscopic observations of the nearby type Ia supernova (SN Ia) SN 2011fe, taken on 10 epochs from -13.5 to +41 days relative to B-band maximum light, and spanning the far-ultraviolet (UV) to the near-infrared (IR) are presented. This spectroscopic coverage makes SN 2011fe the best-studied local SN Ia to date. SN 2011fe is a typical moderately-luminous SN Ia with no evidence for dust extinction. Its near-UV spectral properties are representative of a larger sample of local events studied in Maguire et al. (2012). As a result, conclusions inferred from our detailed investigations are likely representative of those for other normal SNe Ia. The near-UV to optical spectra of SN 2011fe are modelled with a Monte Carlo radiative transfer code using the technique of 'abundance tomography', providing tight constraints on the density structure and abundance stratification of the event. SN 2011fe was a relatively weak explosion, with moderate Fe-group yields. Although its density structure is c...

  1. Nearby Supernova Factory Observations of SN 2005gj: Another TypeIa Supernova in a Massive Circumstellar Envelope

    SciTech Connect (OSTI)

    Aldering, G.; Antilogus, P.; Bailey, S.; Baltay, C.; Bauer, A.; Blanc, N.; Bongard, S.; Copin, Y.; Gangler, E.; Gilles, S.; Kessler, R.; Kocevski, D.; Lee, B.C.; Loken, S.; Nugent, P.; Pain, R.; Pecontal, E.; Pereira, R.; Perlmutter, S.; Rabinowitz, D.; Rigaudier, G.; Scalzo, R.; Smadja, G.; Thomas, R.C.; Wang, L.; Weaver, B.A.; Rabinowitz, D.; Bauer, A.

    2006-06-01

    We report the independent discovery and follow-up observations of supernova 2005gj by the Nearby Supernova Factory. This is the second confirmed case of a ''hybrid'' Type Ia/IIn supernova, which like the prototype SN 2002ic, we interpret as the explosion of a white dwarf interacting with a circumstellar medium. Our early-phase photometry of SN 2005gj shows that the strength of the interaction between the supernova ejecta and circumstellar material is much stronger than for SN 2002ic. Our .rst spectrum shows a hot continuum with broad and narrow H{alpha} emission. Later spectra, spanning over 4 months from outburst, show clear Type Ia features combined with broad and narrow H{gamma}, H{beta},H{alpha} and He I {lambda}{lambda}5876,7065 in emission. At higher resolution, P Cygni profiles are apparent. Surprisingly, we also observe an inverted P Cygni profile for [O III] {lambda}5007. We find that the lightcurve and measured velocity of the unshocked circumstellar material imply mass loss as recently as 8 years ago. This is in contrast to SN 2002ic, for which an inner cavity in the circumstellar material was inferred. Within the context of the thin-shell approximation, the early lightcurve is well-described by a flat radial density profile for the circumstellar material. However, our decomposition of the spectra into Type Ia and shock emission components allows for little obscuration of the supernova, suggesting an aspherical or clumpy distribution for the circumstellar material. We suggest that the emission line velocity profiles arise from electron scattering rather than the kinematics of the shock. This is supported by the inferred high densities, and the lack of evidence for evolution in the line widths. Ground- and space-based photometry, and Keck spectroscopy, of the host galaxy are used to ascertain that the host galaxy has low metallicity (Z/Z{sub {circle_dot}} < 0.3; 95% confidence) and that this galaxy is undergoing a significant star formation event that began roughly 200 {+-} 70 Myr ago. We discuss the implications of these observations for progenitor models and cosmology using Type Ia supernovae.

  2. The Impact of Supernovae of Type Ia on Large Scales through the Secular Evolution of their Rate

    E-Print Network [OSTI]

    Laura Greggio

    2004-10-07

    A straightforward formalism to evaluate the impact of Type Ia Supernovae on large scale astrophysical issues is presented, together with analytical formulations for the SNIa rate following an instantaneous burst of Star Formation, for both single and double degenrates SNIa progenitors' models. Some applications of the parametrized formalism are illustrated. In particular, it is shown that the current SNIa rates measured in early and late type galaxies, as well as the Fe Mass-to-Light ratio in clusters of galaxies, favour the double degenerate model.

  3. Super-Eddington wind scenario for the progenitors of type Ia supernovae: Accreting He-rich matter onto white dwarfs

    E-Print Network [OSTI]

    Wang, Bo; Ma, Xin; Liu, Dongdong; Cui, Xiao; Han, Zhanwen

    2015-01-01

    Supernovae of type Ia (SNe Ia) are believed to be thermonuclear explosions of carbon-oxygen white dwarfs (CO WDs). However, the mass accretion process onto CO WDs is still not completely understood. In this paper, we study the accretion of He-rich matter onto CO WDs and explore a scenario in which a strong wind forms on the surface of the WD if the total luminosity exceeds the Eddington limit. Using a stellar evolution code called modules for experiments in stellar astrophysics (MESA), we simulated the He accretion process onto CO WDs for WDs with masses of 0.6-1.35Msun and various accretion rates of 10^{-8}-10^{-5}Msun/yr. If the contribution of the total luminosity is included when determining the Eddington accretion rate, then a super-Eddington wind could be triggered at relatively lower accretion rates than those of previous studies based on steady-state models. The super-Eddington wind can prevent the WDs with high accretion rates from evolving into red-giant-like He stars. We found that the contribution...

  4. Inland EmpIrE mErchandIsE Exports calIfornIa statE UnIvErsIty fUllErton

    E-Print Network [OSTI]

    de Lijser, Peter

    Inland EmpIrE mErchandIsE Exports calIfornIa statE UnIvErsIty fUllErton 20122012 CSUF Mihaylo University, Fullerton An Overview and Analysis of Inland Empire Exports #12;novEmbEr 2011 InstItUtE for EconomIc and EnvIronmEntal stUdIEs33 #12;Inland EmpIrE mErchandIsE Exports calIfornIa statE UnIvErsIty f

  5. Microsoft Word - Impact_DSR_on_Transmission_Planning_Final.docx

    Energy Savers [EERE]

    CO2R RPSN BAU EEDR CO2N CO2R RPSN BAU EEDR CO2N CO2R RPSN Southwest Southeast Midwest Central Northeast Genertion (TWh) Low Demand Base Demand High Demand 15 In the...

  6. Gen. Tech. Rep. PSW-101 Berkeley, CA. Pacific Southwest Forest and Range Experiment Station, Forest Service, U.S. Department of Agriculture; 1987.

    E-Print Network [OSTI]

    of "high tech" causing lethargy in implementation. 6. Time lag in technology transfer. 7. The "vision are simplifying computer output. 13. Implementation of "high tech" is putting 21st century technology into 19Gen. Tech. Rep. PSW-101 Berkeley, CA. Pacific Southwest Forest and Range Experiment Station, Forest

  7. Gen. Tech. Rep. PSW-100. Berkeley, CA. Pacific Southwest Forest and Range Experiment Station, Forest Service, U.S. Department of Agriculture; 1987.

    E-Print Network [OSTI]

    Gen. Tech. Rep. PSW-100. Berkeley, CA. Pacific Southwest Forest and Range Experiment Station, Forest Service, U.S. Department of Agriculture; 1987. The University of California's Woody Biomass increasing energy costs, national interest in the development of alternative energy sources began to develop

  8. Desalination is here. In the arid southwest, from Texas to California, as well as in Florida and a few other states, the demand for freshwater

    E-Print Network [OSTI]

    Kamat, Vineet R.

    Desalination is here. In the arid southwest, from Texas to California, as well as in Florida of sustainability, desalination presents particular problems, not only in the energy used to accomplish the desalination itself (where great progress has been made in the past 20 years), but in all of the ancillary

  9. Published in 2009 by John Wiley & Sons, Ltd Correspondence to: David A. Laird, USDA, ARS, National Soil Tilth Laboratory, 2110 University Blvd., Ames IA 50011-3120, USA.

    E-Print Network [OSTI]

    Lehmann, Johannes

    of the pyrolysis platform for coproducing bio-oil and biochar David A. Laird, USDA-ARS-National Soil Tilth Soil Tilth Laboratory, 2110 University Blvd., Ames IA 50011-3120, USA. E-mail: david:547­562 (2009) Abstract: Pyrolysis is a relatively simple, inexpensive, and robust thermochemical technology

  10. 50,000-Watt AM Stations IA | MB | MI | MN | NE | ND | ON | SD | WI | Station News | Owners | TV Captures | Links

    E-Print Network [OSTI]

    Allen, Gale

    that broadcast with a power of 50,000 Watts day and night. Some of these stations are what was once known50,000-Watt AM Stations IA | MB | MI | MN | NE | ND | ON | SD | WI | Station News | Owners | TV Captures | Links 50,000-Watt AM stations This list includes AM stations in the United States and Canada

  11. Determining the motion of the solar system relative to the cosmic microwave background using type Ia supernovae

    E-Print Network [OSTI]

    Christopher Gordon; Kate Land; Anze Slosar

    2008-04-04

    We estimate the solar system motion relative to the cosmic microwave background using type Ia supernovae (SNe) measurements. We take into account the correlations in the error bars of the SNe measurements arising from correlated peculiar velocities. Without accounting for correlations in the peculiar velocities, the SNe data we use appear to detect the peculiar velocity of the solar system at about the 3.5 sigma level. However, when the correlations are correctly accounted for, the SNe data only detects the solar system peculiar velocity at about the 2.5 sigma level. We forecast that the solar system peculiar velocity will be detected at the 9 sigma level by GAIA and the 11 sigma level by the LSST. For these surveys we find the correlations are much less important as most of the signal comes from higher redshifts where the number density of SNe is insufficient for the correlations to be important.

  12. The INTEGRAL/SPI 511 keV Signal from Hidden Valleys in Type Ia and Core Collapse Supernova Explosions

    E-Print Network [OSTI]

    Hooman Davoudiasl; Gilad Perez

    2010-04-03

    We examine under what circumstances the INTEGRAL/SPI 511 keV signal can originate from decays of MeV-scale composite states produced by: (A) thermonuclear (type Ia) or (B) core collapse supernovae (SNe). The requisite dynamical properties that would account for the observed data are quite distinct, for cases (A) and (B). We determine these requirements in simple hidden valley models, where the escape fraction problem is naturally addressed, due to the long lifetime of the new composite states. A novel feature of scenario (A) is that the dynamics of type Ia SNe, standard candles for cosmological measurements, might be affected by our mechanism. In case (A), the mass of the state mediating between the hidden sector and the SM $\\ee$ could be a few hundred GeV and within the reach of a 500 GeV $\\ee$ linear collider. We also note that kinetic mixing of the photon with a light vector state may provide an interesting alternate mediation mechanism in this case. Scenarios based on case (B) are challenged by the need for a mechanism to transport some of the produced positrons toward the Galactic bulge, due to the inferred distribution of core collapse sources. The mass of the mediator in case (B) is typically hundreds of TeV, leading to long-lived particles that could, under certain circumstances, include a viable dark matter candidate. The appearance of long-lived particles in typical models leads to cosmological constraints and we address how a consistent cosmic history may be achieved.

  13. Multi-Color Light Curves of Type Ia Supernovae on the Color-Magnitude Diagram: a Novel Step Toward More Precise Distance and Extinction Estimates

    E-Print Network [OSTI]

    Lifan Wang; Gerson Goldhaber; Greg Aldering; Saul Perlmutter

    2003-02-17

    We show empirically that fits to the color-magnitude relation of Type Ia supernovae after optical maximum can provide accurate relative extragalactic distances. We report the discovery of an empirical color relation for Type Ia light curves: During much of the first month past maximum, the magnitudes of Type Ia supernovae defined at a given value of color index have a very small magnitude dispersion; moreover, during this period the relation between $B$ magnitude and $B-V$ color (or $B-R$ or $B-I$ color) is strikingly linear, to the accuracy of existing well-measured data. These linear relations can provide robust distance estimates, in particular, by using the magnitudes when the supernova reaches a given color. After correction for light curve strech factor or decline rate, the dispersion of the magnitudes taken at the intercept of the linear color-magnitude relation are found to be around 0$^m$.08 for the sub-sample of supernovae with \\BVm $\\le 0^m.05$, and around 0$^m$.11 for the sub-sample with \\BVm $\\le 0^m.2$. This small dispersion is consistent with being mostly due to observational errors. The method presented here and the conventional light curve fitting methods can be combined to further improve statistical dispersions of distance estimates. It can be combined with the magnitude at maximum to deduce dust extinction. The slopes of the color-magnitude relation may also be used to identify intrinsically different SN Ia systems. The method provides a tool that is fundamental to using SN Ia to estimate cosmological parameters such as the Hubble constant and the mass and dark energy content of the universe.

  14. Intrinsic Case Study of Advisors’ Perceptions of Advising International Transfer Students Transitioning from a Two-Year College to a Land-Grant University in the Southwest Region of the United States 

    E-Print Network [OSTI]

    De Sousa, David Alexandre

    2014-12-15

    This qualitative intrinsic case study examined advisor’s perceptions of advising transitioning international transfer students transferring from a two-year college to a land-grant institution in the southwest region on the United States. Literature...

  15. Cosmological constraints from measurements of type Ia supernovae discovered during the first 1.5 yr of the Pan-STARRS1 survey

    SciTech Connect (OSTI)

    Rest, A. [Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218 (United States); Scolnic, D.; Riess, A.; Rodney, S.; Brout, D. [Department of Physics and Astronomy, Johns Hopkins University, 3400 North Charles Street, Baltimore, MD 21218 (United States); Foley, R. J.; Chornock, R.; Berger, E.; Soderberg, A. M.; Stubbs, C. W.; Kirshner, R. P.; Challis, P.; Czekala, I.; Drout, M. [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Huber, M. E.; Tonry, J. L. [Institute for Astronomy, University of Hawaii, 2680 Woodlawn Drive, Honolulu, HI 96822 (United States); Narayan, G. [Department of Physics, Harvard University, 17 Oxford Street, Cambridge, MA 02138 (United States); Smartt, S. J. [Astrophysics Research Centre, School of Mathematics and Physics, Queens University Belfast, Belfast BT71NN (United Kingdom); Schlafly, E. [Max Planck Institute for Astronomy, Königstuhl 17, D-69117 Heidelberg (Germany); Botticella, M. T. [INAF-Osservatorio Astronomico di Capodimonte, Salita Moiariello 16, I-80131 Napoli (Italy); and others

    2014-11-01

    We present griz {sub P1} light curves of 146 spectroscopically confirmed Type Ia supernovae (SNe Ia; 0.03 < z < 0.65) discovered during the first 1.5 yr of the Pan-STARRS1 Medium Deep Survey. The Pan-STARRS1 natural photometric system is determined by a combination of on-site measurements of the instrument response function and observations of spectrophotometric standard stars. We find that the systematic uncertainties in the photometric system are currently 1.2% without accounting for the uncertainty in the Hubble Space Telescope Calspec definition of the AB system. A Hubble diagram is constructed with a subset of 113 out of 146 SNe Ia that pass our light curve quality cuts. The cosmological fit to 310 SNe Ia (113 PS1 SNe Ia + 222 light curves from 197 low-z SNe Ia), using only supernovae (SNe) and assuming a constant dark energy equation of state and flatness, yields w=?1.120{sub ?0.206}{sup +0.360}(Stat){sub ?0.291}{sup +0.269}(Sys). When combined with BAO+CMB(Planck)+H {sub 0}, the analysis yields ?{sub M}=0.280{sub ?0.012}{sup +0.013} and w=?1.166{sub ?0.069}{sup +0.072} including all identified systematics. The value of w is inconsistent with the cosmological constant value of –1 at the 2.3? level. Tension endures after removing either the baryon acoustic oscillation (BAO) or the H {sub 0} constraint, though it is strongest when including the H {sub 0} constraint. If we include WMAP9 cosmic microwave background (CMB) constraints instead of those from Planck, we find w=?1.124{sub ?0.065}{sup +0.083}, which diminishes the discord to <2?. We cannot conclude whether the tension with flat ?CDM is a feature of dark energy, new physics, or a combination of chance and systematic errors. The full Pan-STARRS1 SN sample with ?three times as many SNe should provide more conclusive results.

  16. THE TIP OF THE RED GIANT BRANCH DISTANCES TO TYPE Ia SUPERNOVA HOST GALAXIES. II. M66 AND M96 IN THE LEO I GROUP

    SciTech Connect (OSTI)

    Lee, Myung Gyoon; Jang, In Sung, E-mail: mglee@astro.snu.ac.kr, E-mail: isjang@astro.snu.ac.kr [Astronomy Program, Department of Physics and Astronomy, Seoul National University, Gwanak-gu, Seoul 151-742 (Korea, Republic of)

    2013-08-10

    M66 and M96 in the Leo I Group are nearby spiral galaxies hosting Type Ia supernovae (SNe Ia). We estimate the distances to these galaxies from the luminosity of the tip of the red giant branch (TRGB). We obtain VI photometry of resolved stars in these galaxies from F555W and F814W images in the Hubble Space Telescope archive. From the luminosity function of these red giants, we find the TRGB I-band magnitude to be I{sub TRGB} = 26.20 {+-} 0.03 for M66 and 26.21 {+-} 0.03 for M96. These values yield distance modulus (m - M){sub 0} = 30.12 {+-} 0.03(random) {+-} 0.12(systematic) for M66 and (m - M){sub 0} = 30.15 {+-} 0.03(random) {+-} 0.12(systematic) for M96. These results show that they are indeed the members of the same group. With these results we derive absolute maximum magnitudes of two SNe (SN 1989B in M66 and SN 1998bu in M96). V-band magnitudes of these SNe Ia are {approx}0.2 mag fainter than SN 2011fe in M101, one of the nearest recent SNe Ia. We also derive near-infrared magnitudes for SN 1998bu. Optical magnitudes of three SNe Ia (SN 1989B, SN 1998bu, and SN 2011fe) based on TRGB analysis yield a Hubble constant, H{sub 0} = 68.4 {+-} 2.6(random) {+-} 3.7(systematic) km s{sup -1} Mpc{sup -1}. This value is similar to the values derived from recent WMAP9 results, H{sub 0} = 69.32 {+-} 0.80 km s{sup -1} Mpc{sup -1}, and from Planck results, H{sub 0} = 67.3 {+-} 1.2 km s{sup -1} Mpc{sup -1}, but smaller than other recent determinations based on Cepheid calibration for SNe Ia luminosity, H{sub 0} = 74 {+-} 3 km s{sup -1} Mpc{sup -1}.

  17. Validation and Comparison of Carbon Sequestration Project Cost Models with Project Cost Data Obtained from the Southwest Partnership

    SciTech Connect (OSTI)

    Robert Lee; Reid Grigg; Brian McPherson

    2011-04-15

    Obtaining formal quotes and engineering conceptual designs for carbon dioxide (CO{sub 2}) sequestration sites and facilities is costly and time-consuming. Frequently, when looking at potential locations, managers, engineers and scientists are confronted with multiple options, but do not have the expertise or the information required to quickly obtain a general estimate of what the costs will be without employing an engineering firm. Several models for carbon compression, transport and/or injection have been published that are designed to aid in determining the cost of sequestration projects. A number of these models are used in this study, including models by J. Ogden, MIT's Carbon Capture and Sequestration Technologies Program Model, the Environmental Protection Agency and others. This report uses the information and data available from several projects either completed, in progress, or conceptualized by the Southwest Regional Carbon Sequestration Partnership on Carbon Sequestration (SWP) to determine the best approach to estimate a project's cost. The data presented highlights calculated versus actual costs. This data is compared to the results obtained by applying several models for each of the individual projects with actual cost. It also offers methods to systematically apply the models to future projects of a similar scale. Last, the cost risks associated with a project of this scope are discussed, along with ways that have been and could be used to mitigate these risks.

  18. EIS-0005-S2: Bonneville Power Administration Proposed FY 1979 Program Facility Planning Supplement Southwest Oregon Area Service, Supplemental

    Broader source: Energy.gov [DOE]

    This statement, one of a series prepared by the U.S. Department of Energy’s Bonneville Power Administration on various facets of its construction and maintenance activities, addresses the potential impact of a major new facility proposed for fiscal year 1979. To allow power generated in Wyoming to be delivered to Southwest Oregon and to facilitate the exchange of electric power between the Pacific Northwest and the Middle Snake region, two basic plans of service, each with two corridor routing options, have been identified to meet system requirements. BPA proposes construction of the following two transmission facilities: (1) a 500-kV line from Idaho Power Company's Brownlee Substation in Idaho to BPA's Slatt Substation near Arlington, Oregon, and (2) a 500-kV line from Buckley (near Maupin, Oregon) to Malin, Oregon. This statement must be reviewed and used in conjunction with the overall programmatic environmental statement entitled ""The Role of the Bonneville Power Administration in the Pacific Northwest Power Supply System, Including Its Participation in the Hydro-Thermal Power Program: A Program Environmental Statement and Planning Report (The ""Role EIS""), particularly Appendix B - BPA Power Transmission.

  19. Superfund Record of Decision (EPA Region 7): Vogel Paint and Wax, Maurice, IA. (First remedial action), September 1989. Final report

    SciTech Connect (OSTI)

    Not Available

    1989-09-20

    The Vogel Paint and Wax (VPW) site is an approximately two-acre disposal area two miles southwest of the town of Maurice, in Sioux County, Iowa. Adjacent land uses are primarily agricultural; however, several private residences are within one-quarter mile of the site. A surficial sand and gravel aquifer underlies the site and supplies nearby private wells and the Southern Sioux County Rural Water System, located a mile and one half southeast of the site. Paint sludge, resins, solvents, and other paint-manufacturing wastes were disposed of at the site between 1971 and 1979. VPW records indicate that approximately 43,000 gallons of aliphatic and aromatic hydrocarbons and 6,000 pounds of metals waste were buried at the site. The primary contaminants of concern affecting the soil and ground water are VOCs including benzene, toluene, and xylenes; and metals including chromium and lead. The selected remedial action for this site includes excavation of contaminated soil and separation of solid and liquid wastes; onsite bioremediation of 3,000 cubic yards of the contaminated soil in a fully contained surface impoundment unit, or onsite thermal treatment if soil contains high metal content; and stabilization of treated soil, if necessary to prevent leaching of metals, followed by disposal in the excavated area.

  20. Multi-Color Light Curves of Type Ia Supernovae on the Color-Magnitude Diagram a Novel Step Toward More Precise Distance and Extinction Estimates

    E-Print Network [OSTI]

    Wang, L; Aldering, G; Perlmutter, S; Wang, Lifan; Goldhaber, Gerson; Aldering, Greg; Perlmutter, Saul

    2003-01-01

    We show empirically that fits to the color-magnitude relation of Type Ia supernovae after optical maximum can provide accurate relative extragalactic distances. We report the discovery of an empirical color relation for Type Ia light curves: During much of the first month past maximum, the magnitudes of Type Ia supernovae defined at a given value of color index have a very small magnitude dispersion; moreover, during this period the relation between $B$ magnitude and $B-V$ color (or $B-R$ or $B-I$ color) is strikingly linear, to the accuracy of existing well-measured data. These linear relations can provide robust distance estimates, in particular, by using the magnitudes when the supernova reaches a given color. After correction for light curve strech factor or decline rate, the dispersion of the magnitudes taken at the intercept of the linear color-magnitude relation are found to be around 0$^m$.08 for the sub-sample of supernovae with \\BVm $\\le 0^m.05$, and around 0$^m$.11 for the sub-sample with \\BVm $\\le...

  1. The Very Early Light Curve of SN 2015F in NGC 2442: A Possible Detection of Shock-Heated Cooling Emission and Constraints on SN Ia Progenitor System

    E-Print Network [OSTI]

    Im, Myungshin; Yoon, Sung-Chul; Kim, Jae-Woo; Ehgamberdiev, Shuhrat A; Monard, Libert A G; Sung, Hyun-Il

    2015-01-01

    The main progenitor candidate of Type Ia supernovae (SNe Ia) is white dwarfs in binary systems where the companion star is another white dwarf (double degenerate system) or a less evolved non-degenerate star with R* >~ 0.1 Rsun (single degenerate system), but no direct observational evidence exists that tells which progenitor system is more common. Recent studies suggest that the light curve of a supernova shortly after its explosion can be used to set a limit on the progenitor size, R*. Here, we report a high cadence monitoring observation of SN 2015F, a normal SN Ia, in the galaxy NGC 2442 starting about 84 days before the first light time. With our daily cadence data, we catch the emergence of the radioactively powered light curve, but more importantly detect with a > 97.4% confidence a possible dim precursor emission that appears at roughly 1.5 days before the rise of the radioactively powered emission. The signal is consistent with theoretical expectations for a progenitor system involving a companion st...

  2. ASYMMETRY IN THE OBSERVED METAL-RICH EJECTA OF THE GALACTIC TYPE IA SUPERNOVA REMNANT G299.2–2.9

    SciTech Connect (OSTI)

    Post, Seth; Park, Sangwook [Department of Physics, University of Texas at Arlington, Arlington, Box 19059, TX 76019 (United States); Badenes, Carles [Department of Physics and Astronomy and Pittsburgh Particle Physics, Astrophysics, and Cosmology Center (PITT-PACC), University of Pittsburgh, 3941 OHara Street, Pittsburgh, PA 15260 (United States); Burrows, David N. [Department of Astronomy and Astrophysics, Pennsylvania State University, 525 Davey Laboratory, University Park, PA 16802 (United States); Hughes, John P. [Department of Physics and Astronomy, Rutgers University, 136 Frelinghuysen Road, Piscataway, NJ 08854-8019 (United States); Lee, Jae-Joon [Korea Astronomy and Space Science Institute, Daejeon 305-348 (Korea, Republic of); Mori, Koji [Department of Applied Physics, University of Miyazaki, 1-1 Gakuen Kibana-dai Nishi, Miyazaki 889-2192 (Japan); Slane, Patrick O., E-mail: seth.post@mavs.uta.edu, E-mail: badenes@pitt.edu, E-mail: burrows@astro.psu.edu, E-mail: jph@physics.rutgers.edu, E-mail: mori@astro.miyazaki-u.ac.jp, E-mail: slane@cfa.harvard.edu [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States)

    2014-09-01

    We have performed a deep Chandra observation of the Galactic Type Ia supernova remnant G299.2–2.9. Here we report the initial results from our imaging and spectral analysis. The observed abundance ratios of the central ejecta are in good agreement with those predicted by delayed-detonation Type Ia supernovae models. We reveal inhomogeneous spatial and spectral structures of metal-rich ejecta in G299.2–2.9. The Fe/Si abundance ratio in the northern part of the central ejecta region is higher than that in the southern part. A significant continuous elongation of ejecta material extends out to the western outermost boundary of the remnant. In this western elongation, both the Si and Fe are enriched with a similar abundance ratio to that in the southern part of the central ejecta region. These structured distributions of metal-rich ejecta material suggest that this Type Ia supernova might have undergone a significantly asymmetric explosion and/or has been expanding into a structured medium.

  3. The 1999aa-like Type Ia Supernova iPTF14bdn in the Ultraviolet and Optical

    E-Print Network [OSTI]

    Smitka, Michael T; Suntzeff, Nicholas B; Zhang, Jujia; Wang, Xiaofeng; Zhai, Qian; Mo, Jun; Zhang, Tianmeng

    2015-01-01

    We present ultraviolet (UV) and optical photometry and spectra of the 1999aa-like supernova (SN) iPTF14bdn. The UV data were observed using the Swift Ultraviolet/Optical Telescope (UVOT) and constitute the first UV spectral series of a 1999aa-like SN. From the photometry we measure $\\Delta m_{15}({\\it B})\\,=\\,0.84 \\pm0.05$ mag and blue UV colors at epochs earlier than $-5$ days. The spectra show that the early-time blue colors are the result of less absorption between $2800 - 3200 \\,\\AA~$ than is present in normal SNe Ia. Using model spectra fits of the data at $-10 $ and $+10 $ days, we identify the origin of this spectral feature to be a temperature effect in which doubly ionized iron group elements create an opacity 'window'. We determine that the detection of high temperatures and large quantities of iron group elements at early epochs imply the mixing of a high Ni mass into the outer layers of the SN ejecta. We also identify the source of the I-band secondary maximum in iPTF14bdn to be the decay of Fe II...

  4. No X-rays from the very nearby type Ia SN 2014J: Constraints on its environment

    SciTech Connect (OSTI)

    Margutti, R.; Parrent, J.; Kamble, A.; Soderberg, A. M.; Milisavljevic, D.; Drout, M. R.; Kirshner, R. [Harvard-Smithsonian Center for Astrophysics, 60 Garden St., Cambridge, MA 02138 (United States); Foley, R. J. [Astronomy Department, University of Illinois at Urbana-Champaign, 1002 W. Green Street, Urbana, IL 61801 (United States)

    2014-07-20

    Deep X-ray observations of the post-explosion environment around the very nearby Type Ia SN 2014J (d{sub L} = 3.5 Mpc) reveal no X-ray emission down to a luminosity L{sub x} < 7 × 10{sup 36} erg s{sup –1} (0.3-10 keV) at ?t ? 20 days after the explosion. We interpret this limit in the context of inverse Compton emission from upscattered optical photons by the supernova shock and constrain the pre-explosion mass-loss rate of the stellar progenitor system to be M-dot <10{sup ?9} M{sub ?} yr{sup ?1} (for wind velocity v{sub w} = 100 km s{sup –1}). Alternatively, the SN shock might be expanding into a uniform medium with density n{sub CSM} < 3 cm{sup –3}. These results rule out single-degenerate (SD) systems with steady mass loss until the terminal explosion and constrain the fraction of transferred material lost at the outer Lagrangian point to be ?1%. The allowed progenitors are (1) white dwarf-white dwarf progenitors, (2) SD systems with unstable hydrogen burning experiencing recurrent nova eruptions with recurrence time t < 300 yr, and (3) stars where the mass loss ceases before the explosion.

  5. Reservoir characterization of the Ordovician Red River Formation in southwest Williston Basin Bowman County, ND and Harding County, SD

    SciTech Connect (OSTI)

    Sippel, M.A.; Luff, K.D.; Hendricks, M.L.; Eby, D.E.

    1998-07-01

    This topical report is a compilation of characterizations by different disciplines of the Red River Formation in the southwest portion of the Williston Basin and the oil reservoirs which it contains in an area which straddles the state line between North Dakota and South Dakota. Goals of the report are to increase understanding of the reservoir rocks, oil-in-place, heterogeneity, and methods for improved recovery. The report is divided by discipline into five major sections: (1) geology, (2) petrography-petrophysical, (3) engineering, (4) case studies and (5) geophysical. Interwoven in these sections are results from demonstration wells which were drilled or selected for special testing to evaluate important concepts for field development and enhanced recovery. The Red River study area has been successfully explored with two-dimensional (2D) seismic. Improved reservoir characterization utilizing 3-dimensional (3D) and has been investigated for identification of structural and stratigraphic reservoir compartments. These seismic characterization tools are integrated with geological and engineering studies. Targeted drilling from predictions using 3D seismic for porosity development were successful in developing significant reserves at close distances to old wells. Short-lateral and horizontal drilling technologies were tested for improved completion efficiency. Lateral completions should improve economics for both primary and secondary recovery where low permeability is a problem and higher density drilling is limited by drilling cost. Low water injectivity and widely spaced wells have restricted the application of waterflooding in the past. Water injection tests were performed in both a vertical and a horizontal well. Data from these tests were used to predict long-term injection and oil recovery.

  6. On the source of the dust extinction in type Ia supernovae and the discovery of anomalously strong Na I absorption

    SciTech Connect (OSTI)

    Phillips, M. M.; Morrell, Nidia; Hsiao, E. Y.; Campillay, Abdo; Contreras, Carlos [Carnegie Observatories, Las Campanas Observatory, Casilla 601, La Serena (Chile); Simon, Joshua D.; Burns, Christopher R.; Persson, Sven E.; Thompson, I. B.; Freedman, Wendy L. [Observatories of the Carnegie Institution for Science, 813 Santa Barbara St., Pasadena, CA 91101 (United States); Cox, Nick L. J. [Instituut voor Sterrenkunde, KU Leuven, Celestijnenlaan 200D bus 2401, 3001 Leuven (Belgium); Foley, Ryan J. [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Karakas, Amanda I. [Research School of Astronomy and Astrophysics, The Australian National University, Weston, ACT 2611 (Australia); Patat, F. [European Southern Observatory (ESO), Karl Schwarschild Strasse 2, D-85748, Garching bei München (Germany); Sternberg, A. [Max Planck Institute for Astrophysics, Karl Schwarzschild Strasse 1, D-85741 Garching bei München (Germany); Williams, R. E. [Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218 (United States); Gal-Yam, A. [Benoziyo Center for Astrophysics, Faculty of Physics, Weizmann Institute of Science, Rehovot 76100 (Israel); Leonard, D. C. [Department of Astronomy, San Diego State University, San Diego, CA 92182 (United States); Stritzinger, Maximilian [Department of Physics and Astronomy, Aarhus University, Ny Munkegade 120, DK-8000 Aarhus C (Denmark); Folatelli, Gastón, E-mail: mmp@lco.cl [Kavli Institute for the Physics and Mathematics of the Universe, Todai Institutes for Advanced Study, the University of Tokyo, Kashiwa 277-8583 (Japan); and others

    2013-12-10

    High-dispersion observations of the Na I D ??5890, 5896 and K I ??7665, 7699 interstellar lines, and the diffuse interstellar band at 5780 Å in the spectra of 32 Type Ia supernovae are used as an independent means of probing dust extinction. We show that the dust extinction of the objects where the diffuse interstellar band at 5780 Å is detected is consistent with the visual extinction derived from the supernova colors. This strongly suggests that the dust producing the extinction is predominantly located in the interstellar medium of the host galaxies and not in circumstellar material associated with the progenitor system. One quarter of the supernovae display anomalously large Na I column densities in comparison to the amount of dust extinction derived from their colors. Remarkably, all of the cases of unusually strong Na I D absorption correspond to 'Blueshifted' profiles in the classification scheme of Sternberg et al. This coincidence suggests that outflowing circumstellar gas is responsible for at least some of the cases of anomalously large Na I column densities. Two supernovae with unusually strong Na I D absorption showed essentially normal K I column densities for the dust extinction implied by their colors, but this does not appear to be a universal characteristic. Overall, we find the most accurate predictor of individual supernova extinction to be the equivalent width of the diffuse interstellar band at 5780 Å, and provide an empirical relation for its use. Finally, we identify ways of producing significant enhancements of the Na abundance of circumstellar material in both the single-degenerate and double-degenerate scenarios for the progenitor system.

  7. 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.

  8. Midwest Region Combined Heat and Power Projects

    Broader source: Energy.gov [DOE]

    DOE's CHP Technical Assistance Partnerships (CHP TAPs) have compiled a select number of combined heat and power (CHP) project profiles, which are available as Adobe Acrobat PDFs. 

  9. Midwest Big Data Hub Edward Seidel

    E-Print Network [OSTI]

    -enabled Transformation of Science Astronomy 1500- 2000: · Single scientist looks through telescope · Record KB of data in notebook · Require reproducibility Sloan Digital Sky Survey 2000+ · Record data for decade (40TB) · Serve of chemists and materials scientists developing a "materials genome" · Industry access can speed product

  10. Water Balance of the 1993 Midwest Flood 

    E-Print Network [OSTI]

    Mizgalewicz, Pawel J.; Maidment, David R.; White, W. Scott; Ridd, Merrill K.

    2003-01-01

    designated for SAST is located at: http://edcwww2.cr.usgs.gov/sast-home.html . Figure 1.1 shows the location and the extent of the SAST study area. This region covers all of the UMRB above St. Louis and that portion of the Missouri Basin whose drainage enters... and Missouri Rivers where the major levee failures occurred. The hydrologic questions were not so readily addressed because of the huge region affected by the flood, some 700,000 km 2 in area. Flood hydrology models are normally applied to regions 100 to 1...

  11. Midwest Partial Differential Equations Conference: Abstracts

    E-Print Network [OSTI]

    Much of the known theory for NLS blowup relies upon energy conservation and is ... Marius Mitrea, "Sharp estimates for Green potentials and a solution of the ...

  12. PROJECT PROFILE: Midwest Renewable Energy Association (Solar...

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

    emerging solar PV market. This region currently has only 3% of the nation's installed solar capacity but is experiencing the fastest growth rate of any region in the US. In an...

  13. Mapping the Midwest Future Kevin D. Kephart

    E-Print Network [OSTI]

    Levinson, David M.

    ;#12;· Five Regional University Centers #12;Bioenergy #12;Biomass Feedstocks Research · More than 200 projects, sustainable, affordable, commercial-scale biomass feedstocks is our first key enabler t

  14. Clean Energy Manufacturing Initiative Midwest Regional Summit...

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

    Lightweighting Breakout Session Summary More Documents & Publications Fiber Reinforced Polymer Composite Manufacturing Workshop Multimaterial Joining Workshop Manufacturing...

  15. Midwest Building Energy Program | Department of Energy

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Delicious Rank EERE:Financing Tool Fits the BillDepartmentSites |StridesBRCPART 970 -Mid-Atlantic

  16. Midwest Biodiesel Producers LLC | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QAsource History ViewMayo, Maryland: Energy ResourcesDec 2005 WindPRO isMickeyWestNewOhio:Midstate ElectricBiodiesel

  17. Midwest Biodiesel Products | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QAsource History ViewMayo, Maryland: Energy ResourcesDec 2005 WindPRO isMickeyWestNewOhio:Midstate

  18. Midwest Grain Processors MGP | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QAsource History ViewMayo, Maryland: Energy ResourcesDec 2005 WindPRO isMickeyWestNewOhio:MidstateCity,Grain

  19. Midwest Renewable Energy Corporation | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QAsource History ViewMayo, Maryland: Energy ResourcesDec 2005 WindPRO

  20. Midwest Wind Energy LLC | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QAsource History ViewMayo, Maryland: Energy ResourcesDec 2005 WindPROLLC Jump to: navigation, search Name:Energy LLC

  1. Midwest Wind Finance LLC | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QAsource History ViewMayo, Maryland: Energy ResourcesDec 2005 WindPROLLC Jump to: navigation, search Name:Energy

  2. Midwest, Wyoming: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QAsource History ViewMayo, Maryland: Energy ResourcesDec 2005 WindPROLLC Jump to: navigation, search

  3. Midwest Energy Cooperative | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QA J-E-1 SECTION J APPENDIX ECoop Inc Jump to: navigation,Mereg GmbH Jump to:EC-LEDSMidAmerican

  4. ITC Midwest LLC | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QA J-E-1 SECTION J APPENDIXsource History View NewGuam:on Openei | Open Energy2010) |OutlookINDEXISEIST EnergyITC

  5. Midwest Forensics Resource Center | The Ames Laboratory

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of NaturalDukeWakefieldSulfateSciTechtail.Theory ofDid you notHeatMaRIEdioxide capture | CenterTechnologies |Five-YearINL

  6. Midwest Underground Technology | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QA J-E-1 SECTION J APPENDIXsource HistoryScenariosMarysvilleMicrogravity-HybridCredits LLC Jump to:

  7. Clean Energy Manufacturing Initiative Midwest Regional Summit:

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of Natural GasAdjustmentsShirleyEnergy A plug-in electric vehicle (PEV) chargingWASHINGTON, DC -

  8. Nonparametric study of the evolution of the cosmological equation of state with SNeIa, BAO, and high-redshift GRBs

    SciTech Connect (OSTI)

    Postnikov, S. [Nuclear Theory Center, Indiana University, Bloomington, IN (United States); Dainotti, M. G. [Physics Department, Stanford University, Via Pueblo Mall 382, Stanford, CA (United States); Hernandez, X. [Instituto de Astronomía, Universidad Nacional Autónoma de México, México D.F. 04510 (Mexico); Capozziello, S., E-mail: spostnik@indiana.edu, E-mail: mdainott@stanford.edu, E-mail: dainotti@oa.uj.edu.pl, E-mail: xavier@astros.unam.mx, E-mail: capozziello@na.infn.it [Dipartimento di Fisica, Universitá di Napoli "Federico II," Compl. Univ. di Monte S. Angelo, Edificio G, Via Cinthia, I-80126 Napoli (Italy)

    2014-03-10

    We study the dark energy equation of state as a function of redshift in a nonparametric way, without imposing any a priori w(z) (ratio of pressure over energy density) functional form. As a check of the method, we test our scheme through the use of synthetic data sets produced from different input cosmological models that have the same relative errors and redshift distribution as the real data. Using the luminosity-time L{sub X} -T{sub a} correlation for gamma-ray burst (GRB) X-ray afterglows (the Dainotti et al. correlation), we are able to utilize GRB samples from the Swift satellite as probes of the expansion history of the universe out to z ? 10. Within the assumption of a flat Friedmann-Lemaître-Robertson-Walker universe and combining supernovae type Ia (SNeIa) data with baryonic acoustic oscillation constraints, the resulting maximum likelihood solutions are close to a constant w = –1. If one imposes the restriction of a constant w, we obtain w = –0.99 ± 0.06 (consistent with a cosmological constant) with the present-day Hubble constant as H {sub 0} = 70.0 ± 0.6km s{sup –1} Mpc{sup –1} and density parameter as ?{sub ?0} = 0.723 ± 0.025, while nonparametric w(z) solutions give us a probability map that is centered at H {sub 0} = 70.04 ± 1km s{sup –1} Mpc{sup –1} and ?{sub ?0} = 0.724 ± 0.03. Our chosen GRB data sample with a full correlation matrix allows us to estimate the amount, as well as quality (errors), of data needed to constrain w(z) in the redshift range extending an order of magnitude beyond the farthest SNeIa measured.

  9. Expectations for the hard x-ray continuum and gamma-ray line fluxes from the typE IA supernova SN 2014J in M82

    SciTech Connect (OSTI)

    The, Lih-Sin [Department of Physics and Astronomy, Clemson University, SC 29634 (United States); Burrows, Adam, E-mail: tlihsin@clemson.edu, E-mail: burrows@astro.princeton.edu [Department of Astrophysical Sciences, Princeton University, Princeton, NJ 08544 (United States)

    2014-05-10

    The hard X-ray continuum and gamma-ray lines from a Type Ia supernova dominate its integrated photon emissions and can provide unique diagnostics of the mass of the ejecta, the {sup 56}Ni yield and spatial distribution, its kinetic energy and expansion speed, and the mechanism of explosion. Such signatures and their time behavior 'X-ray' the bulk debris field in direct fashion, and do not depend on the ofttimes problematic and elaborate UV, optical, and near-infrared spectroscopy and radiative transfer that have informed the study of these events for decades. However, to date no hard photons have ever been detected from a Type Ia supernova in explosion. With the advent of the supernova SN 2014J in M82, at a distance of ?3.5 Mpc, this situation may soon change. Both NuSTAR and INTEGRAL have the potential to detect SN 2014J, and, if spectra and light curves can be measured, would usefully constrain the various explosion models published during the last ?30 yr. In support of these observational campaigns, we provide predictions for the hard X-ray continuum and gamma-line emissions for 15 Type Ia explosion models gleaned from the literature. The model set, containing as it does deflagration, delayed detonation, merger detonation, pulsational delayed detonation, and sub-Chandrasekhar helium detonation models, collectively spans a wide range of properties, and hence signatures. We provide a brief discussion of various diagnostics (with examples), but importantly make the spectral and line results available electronically to aid in the interpretation of the anticipated data.

  10. Geologic setting, petrophysical characteristics, and regional heterogeneity patterns of the Smackover in southwest Alabama. Draft topical report on Subtasks 2 and 3

    SciTech Connect (OSTI)

    Kopaska-Merkel, D.C.; Mann, S.D.; Tew, B.H.

    1992-06-01

    This is the draft topical report on Subtasks 2 and 3 of DOE contract number DE-FG22-89BC14425, entitled ``Establishment of an oil and gas database for increased recovery and characterization of oil and gas carbonate reservoir heterogeneity.`` This volume constitutes the final report on Subtask 3, which had as its primary goal the geological modeling of reservoir heterogeneity in Smackover reservoirs of southwest Alabama. This goal was interpreted to include a thorough analysis of Smackover reservoirs, which was required for an understanding of Smackover reservoir heterogeneity. This report is divided into six sections (including this brief introduction). Section two, entitled ``Geologic setting,`` presents a concise summary of Jurassic paleogeography, structural setting, and stratigraphy in southwest Alabama. This section also includes a brief review of sedimentologic characteristics and stratigraphic framework of the Smackover, and a summary of the diagenetic processes that strongly affected Smackover reservoirs in Alabama. Section three, entitled ``Analytical methods,`` summarizes all nonroutine aspects of the analytical procedures used in this project. The major topics are thin-section description, analysis of commercial porosity and permeability data, capillary-pressure analysis, and field characterization. ``Smackover reservoir characteristics`` are described in section four, which begins with a general summary of the petrographic characteristics of porous and permeable Smackover strata. This is followed by a more-detailed petrophysical description of Smackover reservoirs.

  11. THE EFFECT OF THE PRE-DETONATION STELLAR INTERNAL VELOCITY PROFILE ON THE NUCLEOSYNTHETIC YIELDS IN TYPE Ia SUPERNOVA

    SciTech Connect (OSTI)

    Kim, Yeunjin; Jordan, G. C. IV; Graziani, Carlo; Lamb, D. Q.; Truran, J. W.; Meyer, B. S.

    2013-07-01

    A common model of the explosion mechanism of Type Ia supernovae is based on a delayed detonation of a white dwarf. A variety of models differ primarily in the method by which the deflagration leads to a detonation. A common feature of the models, however, is that all of them involve the propagation of the detonation through a white dwarf that is either expanding or contracting, where the stellar internal velocity profile depends on both time and space. In this work, we investigate the effects of the pre-detonation stellar internal velocity profile and the post-detonation velocity of expansion on the production of {alpha}-particle nuclei, including {sup 56}Ni, which are the primary nuclei produced by the detonation wave. We perform one-dimensional hydrodynamic simulations of the explosion phase of the white dwarf for center and off-center detonations with five different stellar velocity profiles at the onset of the detonation. In order to follow the complex flows and to calculate the nucleosynthetic yields, approximately 10,000 tracer particles were added to every simulation. We observe two distinct post-detonation expansion phases: rarefaction and bulk expansion. Almost all the burning to {sup 56}Ni occurs only in the rarefaction phase, and its expansion timescale is influenced by pre-existing flow structure in the star, in particular by the pre-detonation stellar velocity profile. We find that the mass fractions of the {alpha}-particle nuclei, including {sup 56}Ni, are tight functions of the empirical physical parameter {rho}{sub up}/v{sub down}, where {rho}{sub up} is the mass density immediately upstream of the detonation wave front and v{sub down} is the velocity of the flow immediately downstream of the detonation wave front. We also find that v{sub down} depends on the pre-detonation flow velocity. We conclude that the properties of the pre-existing flow, in particular the internal stellar velocity profile, influence the final isotopic composition of burned matter produced by the detonation.

  12. ASSESSMENT FOR THE SOUTHWEST

    E-Print Network [OSTI]

    Wong, Pak Kin

    SERVICE CLIMATE CHANGE & CULTURAL RESOURCE PLANNING PROGRAM 17 EARTH SYSTEM MODELS 18 CLIMATE ASSESSMENTS

  13. PACIFIC SOUTHWEST FOREST SERVICE

    E-Print Network [OSTI]

    of a prescribed burn and a wildfire are often small, and too often shift rapidly from pre- scribed to wildfire retardants, and to study effects of fire on soil,vegetation, and air quality. TEST SITE Four acres

  14. PACIFIC SOUTHWEST-' FOREST SERVICE

    E-Print Network [OSTI]

    (measured as a deposit) was used through- out the tests. The aerosols were assessed by two different methods toxic than malathion to larch casebearer larvae. METHODS Insects Overwintering 2nd and 3rd instar larch to the selection of a mixture of Superior Spray Oil 7N5 and tnpropylene glycol monomethylether in the ratio 911 (v

  15. G SOUTHWEST FOREST SERVICE

    E-Print Network [OSTI]

    . This soil is well-drained, runoff is medium, and permeabil- ity is moderately rapid. The soil is slightly.). In 1927, the #12;first attempt was made to clear the pasture of this noxious weed, by digging and burning commercially. The seedlings were graded, and only thrifty trees with 8- to 12-inchtops and well developed root

  16. Ornamentals for Southwest Texas. 

    E-Print Network [OSTI]

    Mortensen, Ernest

    1947-01-01

    and flowering shrubs, vines, bulbs, herbaceous flowers and lawn blanco, mesquite, non-fruiting mu1... in this section. Other useful anti ttractive trees are sycamore, palo blanco, Arizona walnut and cedar lm. For quick results and dense shade, the Texas umbrella is out- tanding, but. the berries are very unsightly in the fall and minter and will probably have...

  17. C SOUTHWEST FOREST SERVICE

    E-Print Network [OSTI]

    annual rainfall of 45 inches. Mean an- nual temperature is 57" F; January temperature aver- ages 54" F steep gulch. Annual rainfall averaged 54 inches for the 11-year period-20 percent higher than the mean

  18. PACIFIC SOUTHWEST FOREST SERVICE

    E-Print Network [OSTI]

    (Fraxinus uhdei Wenzig Lingelsheim), saligna eucalyptus (Eucalyptus salig~laSm. ), Aus- tralian toon (Toona immediately after firetrees were treated. Because only 13 percent of the saligna eucalyptus seedlings were of the original saligna eucalyptus plots.

  19. C SOUTHWEST FOREST SERVICE

    E-Print Network [OSTI]

    LUMBER POTENTIAL OF 12-YEAR-OLD SALlGNA EUCALYPTUS TREES IN HAWAl Roger G. Satolmen USDA F Q P ~ S ~Service Resea~ckl o k g PSW-288 1974 Abstract: The sawtimber potential of 12-year-old Eucalyptus saligna when pressure treated. Oxford: 176.1(969): 812.31: 852:2. Retrieval Terms: Eucalyptus saligna; Hawaii

  20. C SOUTHWEST FOREST SERVICE

    E-Print Network [OSTI]

    ROWH OF YOUNG SALlGNA EUCALYPTUS IN HAWA 6 years after thinning Craig D. Wbibesli One of the most favored introduced tree species for reforestation in Hawaii is saligna eucalyptus (Eu- calyptus saligna Sm. Research NO& p$w-239 Specific guides are needed for management of fast- 1975 growing eucalyptus stands

  1. PACIFIC SOUTHWEST FOREST SERVICE

    E-Print Network [OSTI]

    is on the windward slope of Eucalyptus deglupta B1. (Deglupta eucalyptus) Mauna Kea, 3 miles west of Hakalau, at 1,725 feet Eucalyptus grandis Hillex. Maiden (Rosegum eucalyptus) Myoporum sandwicense (D.C.)Gray (Naio

  2. , SOUTHWEST .. Forest and Range

    E-Print Network [OSTI]

    , under other conditions of weather and topography, on a small group of fires, control effort of them in the short period between September 25 and October 4. The loss of 16 lives can be attrib- uted to the fire activity. More than 700 homes and other structures were burned, and fire damage and suppression

  3. Pacific Southwest Forest & Range

    E-Print Network [OSTI]

    , ( G) support rod, (H) shaft, ( I) cup shaft, (J) body cover plate, and (K) hub. -2- #12;The body. The magnets are imbedded in an aluminum rotor attached to the anemometer shaft (fig. 2). Four magnets are used

  4. IA Blog Archive

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of Natural GasAdjustmentsShirleyEnergy A plug-inPPLforLDRD Report11,SecurityHome . Form D-4-A Government of the District

  5. Gorchakova-IA

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power Administration would likeUniverse (Journalvivo Low-Dose Low LETUsefulJorgeAtl anta, Georgia, March 19-23, 2001

  6. Integrated Vulnerability and Impacts Assessment for Natural and Engineered Water-Energy Systems in the Southwest and Southern Rocky Mountain Region

    SciTech Connect (OSTI)

    Tidwell, Vincent C.; Wolfsberg, Andrew; Macknick, Jordan; Middleton, Richard

    2015-01-01

    In the Southwest and Southern Rocky Mountains (SWSRM), energy production, energy resource extraction, and other high volume uses depend on water supply from systems that are highly vulnerable to extreme, coupled hydro-ecosystem-climate events including prolonged drought, flooding, degrading snow cover, forest die off, and wildfire. These vulnerabilities, which increase under climate change, present a challenge for energy and resource planners in the region with the highest population growth rate in the nation. Currently, analytical tools are designed to address individual aspects of these regional energy and water vulnerabilities. Further, these tools are not linked, severely limiting the effectiveness of each individual tool. Linking established tools, which have varying degrees of spatial and temporal resolution as well as modeling objectives, and developing next-generation capabilities where needed would provide a unique and replicable platform for regional analyses of climate-water-ecosystem-energy interactions, while leveraging prior investments and current expertise (both within DOE and across other Federal agencies).

  7. Paint Rock and southwest Paint Rock fields, Concho County, Texas: Strawn analogs of modern island carbonate facies of Ambergris Cay, Belize

    SciTech Connect (OSTI)

    Reid, A.M.; Mazzullo, S.J.

    1987-02-01

    Lower Strawn (Desmoinesian Goen Limestone) reservoirs at Paint Rock and Southwest Paint Rock fields are a complex of carbonate and associated facies interpreted as having been deposited in various environments on and around large, emergent islands on shallow carbonate shelves. The origin and geometries of the component lithofacies in these fields, and their reservoir diagenetic histories, are similar to those presently accumulating on Ambergris Cay, a linear island complex on the northern shelf of Belize. Paint Rock field originated as a narrow, elongate Chaetetes reef trend that formed the foundation on which the overlying island facies were deposited. As on Ambergris Cay, these reef limestones developed extensive porosity during postdepositional subaerial exposure due to meteoric leaching. In contrast, Southwest Paint Rock field is cored by older island deposits rather than reef limestones. With ensuing stillstand or subsequent sea level rise, beach grainstones were deposited along the windward and leeward margins of the foundation highs in these fields. Tight lagoonal micrites and coals (peat-swamp facies) comprise the inner island facies, and are locally associated with porous supratidal dolomites. These island complexes are transected locally by tidal channels that are filled with nonporous micrites. Repeated sea level fluctuations during the history of these fields resulted in a characteristic cyclic stratigraphy of stacked island facies and reservoirs. The reservoirs in the field are developed in the bedrock or older island cores, as well as in the overlying beach facies and supratidal dolomites. These fields are mappable as linear stratigraphic traps with low-relief closure, and are readily identified by subsurface geologic and facies analyses. Similar shelf island-type fields analogous to these strawn and Holocene Belizean examples are found throughout the Midland basin and Eastern shelf.

  8. Solar Wind: Manifestations of Solar Activity E N CYC LO PE D IA O F AS T R O N O MY AN D AS T R O PHYS I C S Solar Wind: Manifestations of Solar

    E-Print Network [OSTI]

    Webb, David F.

    Solar Wind: Manifestations of Solar Activity E N CYC LO PE D IA O F AS T R O N O MY AN D AS T R O PHYS I C S Solar Wind: Manifestations of Solar Activity The Sun's outer atmosphere, the corona, is continually heated and expands to create the solar wind. Solar activity waxes and wanes with the 11 yr cycle

  9. GEOPHYSI('S, VOL,. 02, NO. 2 (MARC'II-AI'KIL 1097); I! $05-520, 12FICiS., 4 'I'A14L.ES. Parameters controllingsonic velocities in a mixed

    E-Print Network [OSTI]

    Podladchikov, Yuri

    GEOPHYSI('S, VOL,. 02, NO. 2 (MARC'II-AI'KIL 1097); I! $05-520, 12FICiS., 4 'I'A14L.ES. Parameters, Last Chance Canyon, New Mexico) Jeroen A. M. Kenter*, F. F. Podladchikov*, Marc Reinders*,Sjierk J. Van

  10. Linking ecosystem scale vegetation change to shifts in carbon and water cycling: the consequences of widespread piñon mortality in the Southwest

    SciTech Connect (OSTI)

    Litvak, Marcy Ellen [University of New Mexico

    2012-10-01

    The southwestern United States experienced an extended drought from 1999-2002 which led to widespread coniferous tree mortality. Piñon-juniper (PJ) woodlands, which occupy 24 million ha throughout the Southwest, were extremely vulnerable to this drought. An abrupt die-off of 40 to 95% of piñon pine (Pinus edulis) and 2-25% of juniper (Juniperus monosperma) across 1.5 million ha triggered rapid and extensive changes in the structure of PJ woodlands with potentially large, yet unknown, consequences for ecosystem services and feedbacks between the carbon cycle and climate system. Given the spatial extent of PJ woodlands (3rd largest biome in the US) and climatic predictions of increased frequency and intensity of drought in the region, it is crucial to understand the consequences of these disturbances on regional carbon and energy dynamics, biogeochemical processes and atmospheric CO2. The overall objective of our research was to quantify what impact widespread mortality of piñon trees has for carbon and water cycling in PJ woodlands. Our specific objectives for this proposal were: 1) Quantify the carbon, water and energy exchange trajectory after mortality in PJ woodlands; 2) Determine the mechanisms controlling the response and recovery of ecosystem production and respiration processes following large-scale piñon mortality; 3) Use the relationships we measure between ecosystem structure and function PJ woodlands recover from mortality to scale the results of our study up to the regional scale.

  11. ClassName MethodName FieldName(ParamsName)ClassType Period Mark Order Rank Comment ARS NewTypesNum NewTypes AllTypes AllTypesNum MCBINum minidraw.boardgame.BoardDrawing CLASS CL&IA 0 1 MICs 0 0 0 0

    E-Print Network [OSTI]

    Abi-Antoun, Marwan

    Tips: ClassName MethodName FieldName(ParamsName)ClassType Period Mark Order Rank Comment ARS NewTypesNum NewTypes AllTypes AllTypesNum MCBINum minidraw.boardgame.BoardDrawing CLASS CL&IA 0 1 MICs 0 0 0 0 minidraw.standard.MiniDrawApplication CLASS CL&IA 0 2 MICs 0 0 0 0 minidraw.standard.SelectionTool CLASS CL

  12. THE POST-MERGER MAGNETIZED EVOLUTION OF WHITE DWARF BINARIES: THE DOUBLE-DEGENERATE CHANNEL OF SUB-CHANDRASEKHAR TYPE Ia SUPERNOVAE AND THE FORMATION OF MAGNETIZED WHITE DWARFS

    SciTech Connect (OSTI)

    Ji Suoqing; Fisher, Robert T. [University of Massachusetts Dartmouth, Department of Physics, 285 Old Westport Road, North Dartmouth, MA 02740 (United States); Garcia-Berro, Enrique [Departament de Fisica Aplicada, Universitat Politecnica de Catalunya, c/Esteve Terrades, 5, E-08860 Castelldefels (Spain); Tzeferacos, Petros; Jordan, George; Lee, Dongwook [Center for Astrophysical Thermonuclear Flashes, The University of Chicago, Chicago, IL 60637 (United States); Loren-Aguilar, Pablo [School of Physics, University of Exeter, Stocker Road, Exeter EX4 4QL (United Kingdom); Cremer, Pascal [Bethe Center for Theoretical Physics, Universitaet Bonn, Nussallee 12, D-53115 Bonn (Germany); Behrends, Jan [Fachbereich Physik, Freie Universitaet Berlin, Arnimallee 14, D-14195 Berlin (Germany)

    2013-08-20

    Type Ia supernovae (SNe Ia) play a crucial role as standardizable cosmological candles, though the nature of their progenitors is a subject of active investigation. Recent observational and theoretical work has pointed to merging white dwarf binaries, referred to as the double-degenerate channel, as the possible progenitor systems for some SNe Ia. Additionally, recent theoretical work suggests that mergers which fail to detonate may produce magnetized, rapidly rotating white dwarfs. In this paper, we present the first multidimensional simulations of the post-merger evolution of white dwarf binaries to include the effect of the magnetic field. In these systems, the two white dwarfs complete a final merger on a dynamical timescale, and are tidally disrupted, producing a rapidly rotating white dwarf merger surrounded by a hot corona and a thick, differentially rotating disk. The disk is strongly susceptible to the magnetorotational instability (MRI), and we demonstrate that this leads to the rapid growth of an initially dynamically weak magnetic field in the disk, the spin-down of the white dwarf merger, and to the subsequent central ignition of the white dwarf merger. Additionally, these magnetized models exhibit new features not present in prior hydrodynamic studies of white dwarf mergers, including the development of MRI turbulence in the hot disk, magnetized outflows carrying a significant fraction of the disk mass, and the magnetization of the white dwarf merger to field strengths {approx}2 Multiplication-Sign 10{sup 8} G. We discuss the impact of our findings on the origins, circumstellar media, and observed properties of SNe Ia and magnetized white dwarfs.

  13. A Uniform Contribution of Core-Collapse and Type Ia Supernovae to the Chemical Enrichment Pattern in the Outskirts of the Virgo Cluster

    E-Print Network [OSTI]

    Simionescu, A; Urban, O; Allen, S W; Ichinohe, Y; Zhuravleva, I

    2015-01-01

    We present the first measurements of the abundances of alpha-elements (Mg, Si, and S) extending out to beyond the virial radius of a cluster of galaxies. Our results, based on Suzaku Key Project observations of the Virgo Cluster, show that the chemical composition of the intra-cluster medium is constant on large scales, with a flat distribution of the Si/Fe, S/Fe, and Mg/Fe ratios as a function of radius and azimuth out to 1.4 Mpc (1.3 r200). Chemical enrichment of the intergalactic medium due solely to core collapse supernovae (SNcc) is excluded with very high significance; instead, the measured S/Fe and Mg/Fe ratios are consistent with the Solar value, with a sub-solar Si/Fe ratio. The uniform metal abundance ratios observed today are likely the result of an early phase of enrichment and mixing, with both SNcc and type Ia supernovae (SNIa) contributing to the metal budget during the period of peak star formation activity at redshifts of 2-3. We estimate the ratio between the number of SNIa and the total num...

  14. OPTICAL AND NEAR-INFRARED POLARIMETRY OF HIGHLY REDDENED Type Ia SUPERNOVA 2014J: PECULIAR PROPERTIES OF DUST IN M82

    SciTech Connect (OSTI)

    Kawabata, K. S.; Akitaya, H.; Itoh, R.; Moritani, Y. [Hiroshima Astrophysical Science Center, Hiroshima University, Kagamiyama, Higashi-Hiroshima, Hiroshima 739-8526 (Japan); Yamanaka, M. [Department of Physics, Faculty of Science and Engineering, Konan University, Okamoto, Kobe, Hyogo 658-8501 (Japan); Maeda, K.; Nogami, D. [Department of Astronomy, Graduate School of Science, Kyoto University, Sakyo-ku, Kyoto 606-8502 (Japan); Ui, T.; Kawabata, M.; Mori, K.; Takaki, K.; Ueno, I.; Chiyonobu, S.; Harao, T.; Matsui, R.; Miyamoto, H.; Nagae, O. [Department of Physical Science, Hiroshima University, Kagamiyama, Higashi-Hiroshima 739-8526 (Japan); Nomoto, K.; Suzuki, N. [Kavli Institute for the Physics and Mathematics of the Universe (WPI), The University of Tokyo, Kashiwa, Chiba 277-8583 (Japan); Tanaka, M., E-mail: kawabtkj@hiroshima-u.ac.jp [National Astronomical Observatory of Japan, Osawa, Mitaka, Tokyo 181-8588 (Japan); and others

    2014-11-01

    We present optical and near-infrared multi-band linear polarimetry of the highly reddened Type Ia supernova (SN) 2014J that appeared in M82. SN 2014J exhibits large polarization at shorter wavelengths, e.g., 4.8% in the B band, which decreases rapidly at longer wavelengths, while the position angle of the polarization remains at approximately 40° over the observed wavelength range. These polarimetric properties suggest that the observed polarization is likely predominantly caused by the interstellar dust within M82. Further analysis shows that the polarization peaks at a wavelengths much shorter than those obtained for the Galactic dust. The wavelength dependence of the polarization can be better described by an inverse power law rather than by the Serkowski law for Galactic interstellar polarization. These points suggest that the nature of the dust in M82 may be different from that in our Galaxy, with polarizing dust grains having a mean radius of <0.1 ?m.

  15. TYPE Ia SUPERNOVA REMNANT SHELL AT z = 3.5 SEEN IN THE THREE SIGHTLINES TOWARD THE GRAVITATIONALLY LENSED QSO B1422+231

    SciTech Connect (OSTI)

    Hamano, Satoshi; Kobayashi, Naoto [Institute of Astronomy, University of Tokyo, 2-21-1 Osawa, Mitaka, Tokyo 181-0015 (Japan); Kondo, Sohei [Koyama Astronomical Observatory, Kyoto-Sangyo University, Motoyama, Kamigamo, Kita-Ku, Kyoto 603-8555 (Japan); Tsujimoto, Takuji [National Astronomical Observatory of Japan and Department of Astronomical Science, Graduate University for Advanced Studies, 2-21-1 Osawa, Mitaka, Tokyo 181-0015 (Japan); Okoshi, Katsuya [Faculty of Industrial Science and Technology, Tokyo University of Science, 102-1 Tomino, Oshamanbe, Hokkaido 049-3514 (Japan); Shigeyama, Toshikazu, E-mail: hamano@ioa.s.u-tokyo.ac.jp [Research Center for the Early Universe, University of Tokyo, 7-3-1 Hongo, Bunkyo, Tokyo 113-0033 (Japan)

    2012-08-01

    Using the Subaru 8.2 m Telescope with the IRCS Echelle spectrograph, we obtained high-resolution (R = 10,000) near-infrared (1.01-1.38 {mu}m) spectra of images A and B of the gravitationally lensed QSO B1422+231 (z = 3.628) consisting of four known lensed images. We detected Mg II absorption lines at z = 3.54, which show a large variance of column densities ({approx}0.3 dex) and velocities ({approx}10 km s{sup -1}) between sightlines A and B with a projected separation of only 8.4h{sup -1}{sub 70} pc at that redshift. This is the smallest spatial structure of the high-z gas clouds ever detected after Rauch et al. found a 20 pc scale structure for the same z = 3.54 absorption system using optical spectra of images A and C. The observed systematic variances imply that the system is an expanding shell as originally suggested by Rauch et al. By combining the data for three sightlines, we managed to constrain the radius and expansion velocity of the shell ({approx}50-100 pc, 130 km s{sup -1}), concluding that the shell is truly a supernova remnant (SNR) rather than other types of shell objects, such as a giant H II region. We also detected strong Fe II absorption lines for this system, but with much broader Doppler width than that of {alpha}-element lines. We suggest that this Fe II absorption line originates in a localized Fe II-rich gas cloud that is not completely mixed with plowed ambient interstellar gas clouds showing other {alpha}-element low-ion absorption lines. Along with the Fe richness, we conclude that the SNR is produced by an SN Ia explosion.

  16. Strawberry Varieties in Southwest Texas. 

    E-Print Network [OSTI]

    Mortensen, Ernest

    1937-01-01

    , and Thompson. Varieties with good plant pro- duction with records for one year only are Bederarena, Cape Blanco, and Early Bird. Generally poor plant producers are Aberdeen, Beaver, Bellmar, Big Joe, Brandywine, Catskill, Chesapeake, Cooper, Ellinore... ............................................ Rederarena Bellmar.. ................................ Big Blossom. Big Joe. ...................... Big Lagoon ..................... Blakeniore Brandywine Cape Blanco Cape.R/lendocino Catsk~ll.. Champion Klondike ...................... Chesapeake...

  17. PACIFIC SOUTHWEST Forest and Range

    E-Print Network [OSTI]

    -Wheeler Company, Strawberry Valley, California. 1 I ncreasing criticism is being directed at logging operations

  18. PACIFIC SOUTHWEST Forest and Range

    E-Print Network [OSTI]

    evaluating the design trends and market preferences that affect the types of floor foundations. In an earlier-space construction, and for their opinions about the new plenum design. The six markets selected were considered Among Architects and Builders . . . . . . . . . . . . . . . . . 4 Attitudes Toward New Design

  19. PACIFIC SOUTHWEST Forest and Range

    E-Print Network [OSTI]

    P.O. BOX 245, BERKELEY, CALIFORNIA 94701 USDA FOREST SERVICE RESEARCH PAPER PSW- 76 /1971 #12 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 Vegetation Types . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 2--Key to Vegetation Types

  20. PACIFIC SOUTHWEST Forest and Range

    E-Print Network [OSTI]

    OF AGRICULTURE P.O. BOX 245, BERKELEY, CALIFORNIA 94701 SPECIFIC GRAVITY VARIATION IN ROBUSTA EUCALYPTUS grown eucalyptus (Eucalyptus robusta Sm.) is an important timber species in Hawaii. The density, or specific stands of robusta eucalyptus growing along the northeast coast of the island of Hawaii were selected

  1. Desert Southwest Region Ten Year...

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

    carcinogenic characteristics, especially the penta and creosote, and the arsenic is a poison that has proven to cause adverse health effects. Many jurisdictions now consider...

  2. SOUTHWEST CATALYSIS 2015 SPRING SYMPOSIUM

    E-Print Network [OSTI]

    Natelson, Douglas

    Baton Rouge, LA 70817 jnovak@PIDC.com Lin Luo The Dow Chemical Company 2301 Brazosport Blvd., B-251 University Chair #12;3 3 2015 PROGRAM All talks & breaks will be held in Melcher Hall, Room 150 7:30 AM Registration ­ Victor Johnston, Treasurer (& helpers) 8:25 AM Welcoming Remarks ­ Dan Shantz, Chair 8:30 AM Bob

  3. SOUTHWEST CATALYSIS 2012 SPRING SYMPOSIUM

    E-Print Network [OSTI]

    Natelson, Douglas

    Daniel Shantz Chemical Engineering Texas A&M University College Station, TX 77843 979-845-3492 shantz.chandler@trinity.edu Lin Luo Dow Chemical Co. 2301 Brazosport Blvd. B-251 Freeport, TX 77541 979-238-3204 LLuo2@dow Chair #12;2012 PROGRAM 7:30 AM Registration ­ John Novak, Treasurer Duncan Hall All talks will be held

  4. SOUTHWEST CATALYSIS 2012 SPRING SYMPOSIUM

    E-Print Network [OSTI]

    Natelson, Douglas

    Daniel Shantz Chemical Engineering Texas A&M University College Station, TX 77843 979-845-3492 shantz.chandler@trinity.edu Lin Luo Dow Chemical Co. 2301 Brazosport Blvd. B-251 Freeport, TX 77541 979-238-3204 LLuo2@dow #12;2012 PROGRAM 7:30 AM Registration ­ John Novak, Treasurer Duncan Hall All talks will be held in Mc

  5. SOUTHWEST CATALYSIS 2010 SPRING SYMPOSIUM

    E-Print Network [OSTI]

    Natelson, Douglas

    :35 AM Prof. Kerry Dooley (LSU, Baton Rouge, LA) "Perspectives on Catalytic Oxidative Desulfurization" 9' Nanocatalysts for Electrochemical Energy Conversion: The Challenges for Synthesis and Characterization" 1:45 PM Hall ­ McMurtry Auditorium 4:00 PM Adjourn #12;Perspectives on Catalytic Oxidative Desulfurization

  6. Pacific Southwest Forest and Range

    E-Print Network [OSTI]

    costs, economic costs, fire economics, suppression costs, Fire Economics Evaluation System (FEES costs, fire economics, suppression costs, Fire Economics Evaluation System (FEES) Current cost estimates planning and economics research unit, with headquarters at the Forest Fire Laboratory, Riverside, Calif. He

  7. PACIFIC SOUTHWEST Forest and Range

    E-Print Network [OSTI]

    Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 Solar Radiation.211:614 Retrieval Terms: insolation; reproduction; snow management; environ mental planning. Solar radiation environmental factor. Incident solar radia tion creates a secondary form of radiation which af fects the forest

  8. Sunzia Southwest | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page| Open Energy Information Serbia-Enhancing CapacityVectren)Model for theSunLan SolarKoreaSuntechnicsSunwattSunworx

  9. Entertainment Technology Center, CMU Internship Survey Results, Dec 2014 and May 2015

    E-Print Network [OSTI]

    Interviews Arranged by Career Services 12 Intern Search/Company Websites 9 Alumni Contacts 6 West Coast Trip, MS, NC, PR, SC, TN 2 / 4% Midwest: IA, IL, IN, KS, MI, MN, MO, ND, NE, OH, SD, WI 2 / 4% Northwest

  10. Study on proliferative responses to host Ia antigens in allogeneic bone marrow chimera in mice: sequential analysis of the reactivity and characterization of the cells involved in the responses

    SciTech Connect (OSTI)

    Iwabuchi, K.; Ogasawara, K.; Ogasawara, M.; Yasumizu, R.; Noguchi, M.; Geng, L.; Fujita, M.; Good, R.A.; Onoe, K.

    1987-01-01

    Irradiation bone marrow chimeras were established by reconstitution of lethally irradiated AKR mice with C57BL/10 marrow cells to permit serial analysis of the developing reactivities of lymphocytes from such chimeras, (B10----AKR), against donor, host, or third party antigens. We found that substantial proliferative responses to Ia antigens of the recipient strain and also to third party antigens were generated by the thymocytes obtained from the irradiation chimeras at an early stage after bone marrow reconstitution. The majority of the responding thymocytes had surfaces lacking demonstrable peanut agglutinin receptors and were donor type Thy-1+, Ly-2-, and L3T4+ in both anti-recipient and anti-third party MLR. In anti-host responses, however, Ly-2+ thymocytes seemed to be at least partially involved. This capacity of thymus cells to mount a response to antigens of the recipient strain declined shortly thereafter, whereas the capacity to mount MLR against third party antigens persisted. The spleen cells of (B10----AKR) chimeras at the same time developed a more durable capability to exhibit anti-host reactivities and a permanent capability of reacting to third party allo-antigens. The stimulator antigens were Ia molecules on the stimulator cells in both anti-recipient and anti-third party MLR. The responding splenocytes were of donor origin and most of them had Thy-1+, Ly-1+2-, and L3T4+ phenotype.

  11. The Midwest Energy Efficiency Alliance | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page| Open Energy Information Serbia-EnhancingEt Al., 2013) |Information 5thInformationComparisonFacility

  12. Geographic Visualization of the 1993 Midwest Flood Water Balance 

    E-Print Network [OSTI]

    White, W. Scott; Ridd, Merrill K.; Mizgalewicz, Pawel J.; Maidment, David R.

    2003-01-01

    Missouri River basin below Gavins Point dam, South Dakota, to St. Louis, Missouri (Figure 1.1). Using a digital elevation model of the study area, the daily flow into and out of the basin was calculated, and a series of 365 maps of basin water storage were... being stored in the southern part of the UMRB, particularly around the St. Louis area where the Mississippi and Missouri Rivers meet. Water was also being stored in larger than normal amounts along the Missouri River west of St. Louis. By the end...

  13. Tribal Rights, Sovereignty, and Economic Development in the Midwest

    Office of Energy Efficiency and Renewable Energy (EERE)

    Throughout Indian Country, there are significant legal issues impacting Tribal rights and sovereignty. As most of you are aware, Indian Country squeaked out a win for tribal sovereignty in the...

  14. Midwest Consortium for Wind Turbine Reliability and Optimization

    SciTech Connect (OSTI)

    Scott R. Dana; Douglas E. Adams; Noah J. Myrent

    2012-05-11

    This report provides an overview of the efforts aimed to establish a student focused laboratory apparatus that will enhance Purdue's ability to recruit and train students in topics related to the dynamics, operations and economics of wind turbines. The project also aims to facilitate outreach to students at Purdue and in grades K-12 in the State of Indiana by sharing wind turbine operational data. For this project, a portable wind turbine test apparatus was developed and fabricated utilizing an AirX 400W wind energy converter. This turbine and test apparatus was outfitted with an array of sensors used to monitor wind speed, turbine rotor speed, power output and the tower structural dynamics. A major portion of this project included the development of a data logging program used to display real-time sensor data and the recording and creation of output files for data post-processing. The apparatus was tested in an open field to subject the turbine to typical operating conditions and the data acquisition system was adjusted to obtain desired functionality to facilitate use for student projects in existing courses offered at Purdue University and Indiana University. Data collected using the data logging program is analyzed and presented to demonstrate the usefulness of the test apparatus related to wind turbine dynamics and operations.

  15. Sustainable bioenergy production from marginal lands in the US Midwest

    SciTech Connect (OSTI)

    Gelfand, Ilya; Sahajpal, Ritvik; Zhang, Xuesong; Izaurralde, Roberto C.; Gross, Katherine L.; Robertson, G. P.

    2013-01-24

    Long-term measurements of global warming impact coupled with spatially explicit modeling suggests that both climate benefits and the production potential of cellulosic crops grown on marginal lands of the US North Central region are substantial but will be insufficient to meet long-term biofuel needs.

  16. STEM Café Hits the Midwest | Department of Energy

    Energy Savers [EERE]

    radiation detection, the advanced photon source, and even got to see a sample of paint from one of Picasso's works of art. They learned how science, technology, engineering,...

  17. Midwest Appropriate Technology Small Grants Program: management analysis

    SciTech Connect (OSTI)

    Not Available

    1983-10-01

    This report reviews 84 projects conducted with DOE funding. The projects cover a number of energy-related topics, including biomass conversion, solar energy, wind energy, energy education, energy conservation, and recycling. In an effort to assist DOE-Chicago in analyzing what types of grantees were more successful and why, the projects were ranked and grouped by several variables. To determine if particular characteristics functioned to make one project more successful than another, several statistical tests were conducted. While the results of quantitative testing are somewhat offset by the subjective nature of the project rankings, some patterns did seem to develop: The overall distribution of the projects showed a normal division: 23% superior, 55% average, and 23% poor. No particular grantee type was significantly more successful than the others, but colleges and universities did have fewer highly ranked projects than any other group. Michigan had proportionately more superior projects; Illinois and Ohio proportionately fewer. Grant awards over $40,000 yielded fewer superior projects.

  18. Coordination of Retail Demand Response with Midwest ISO Markets

    E-Print Network [OSTI]

    Bharvirkar, Ranjit

    2008-01-01

    The OMS coordinates electricity transmission and wholesalethe regional transmission grid and electricity markets. TheTransmission Organization Real Time Pricing Southern Electricity

  19. Effects of Irrigation on Great Plains and Midwest Precipitation Processes

    E-Print Network [OSTI]

    Huber, David Benjamin

    2010-11-18

    B. Huber, David B. Mechem, and Nathaniel A. Brunsell Outline •Historical and Conceptual Review •Description of Modeling Approach l•Resu ts •Conclusion Historical Changes in Precipitation Climatological Precipitation Differences (1971 – 2000 minus 1901 – 1930) Source: PRISM Climate Group Irrigation... moisture in the lower atmosphere increases Th id i ddhdb h l llj• e evapotranspirated water s advected northward y t e ow level et •Humid air is lifted over higher sensible heat areas by deep convective updrafts •Precipitation events become more intense •Moisture...

  20. Hawkeye Renewables formerly Midwest Renewables | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QAsource History View New PagesSustainableGlynnMassachusetts:Ohio:WebsiteInformation Standards