National Library of Energy BETA

Sample records for in-ocean observations cxs

  1. SMALL-SCALE VARIABILITY IN SEA SURFACE HEIGHTS AND SURFACE WINDS: IMPLICATIONS FOR ERRORS IN OCEAN MODELS AND OBSERVATIONS

    E-Print Network [OSTI]

    Kaplan, Alexey

    SMALL-SCALE VARIABILITY IN SEA SURFACE HEIGHTS AND SURFACE WINDS: IMPLICATIONS FOR ERRORS IN OCEAN on dispersion relationship of planetary waves 4. Small-scale variability in surface winds and sea surface of model and observational data sets. Imperfect parameterization of the small-scale variability (SSV

  2. On zonal jets in oceans Balasubramanya T. Nadiga1

    E-Print Network [OSTI]

    Nadiga, Balasubramanya T. "Balu"

    On zonal jets in oceans Balasubramanya T. Nadiga1 Received 26 January 2006; revised 29 March 2006 to the recently observed alternating zonal jets in oceans, the formation of these jets can be explained as due of alternating jets in Jovian atmospheres and two dimensional turbulence in zonally-periodic configurations

  3. Steroid estrogens in ocean sediments 

    E-Print Network [OSTI]

    Braga, O.; Smythe, G.A.; Schäfer, Andrea; Feitz, A.J.

    2005-01-01

    This paper gives results from a study measuring the abundance of steroid hormones in ocean sediments in the proximity of a deep ocean sewage outfall. The outfall is discharge point for an enhanced primary sewage treatment ...

  4. 2 On zonal jets in oceans 3 Balasubramanya T. Nadiga1

    E-Print Network [OSTI]

    Nadiga, Balasubramanya T. "Balu"

    2 On zonal jets in oceans 3 Balasubramanya T. Nadiga1 4 Received 26 January 2006; revised 29 March to the 7 recently observed alternating zonal jets in oceans, the 8 formation of these jets can be explained, originally studied in the context of 13 alternating jets in Jovian atmospheres and two 14 dimensional

  5. Global warming and changes in ocean circulation

    SciTech Connect (OSTI)

    Duffy, P.B.; Caldeira, K.C.

    1998-02-01

    This final report provides an overview of the goals and accomplishments of this project. Modeling and observational work has raised the possibility that global warming may cause changes in the circulation of the ocean. If such changes would occur they could have important climatic consequences. The first technical goal of this project was to investigate some of these possible changes in ocean circulation in a quantitative way, using a state-of -the-art numerical model of the ocean. Another goal was to develop our ocean model, a detailed three-dimensional numerical model of the ocean circulation and ocean carbon cycles. A major non-technical goal was to establish LLNL as a center of excellence in modelling the ocean circulation and carbon cycle.

  6. ORE 630 Structural Analysis in Ocean Engineering Designation

    E-Print Network [OSTI]

    ORE 630 Structural Analysis in Ocean Engineering Designation Offshore Engineering Required Course Catalog Description Structural and finite element analyses, and design of ocean structures to withstand analysis, finite element analysis, and their application in ocean structure design. Topics Covered 1

  7. Observations

    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 wouldMass mapSpeeding access to scienceSpeedingLightweight MaterialsGasObservation of aof

  8. ORE 630 Structural Analysis in Ocean Engineering Designation

    E-Print Network [OSTI]

    Frandsen, Jannette B.

    to Program Outcomes Program Outcome 2: Basic science, mathematics, & engineering Program Outcome 4: OceanORE 630 Structural Analysis in Ocean Engineering Designation Offshore Engineering Required Course. Design of Ocean Structures. Design process, project planning, materials selection, 6. economic analysis

  9. "Towards Optics-Based Measurements in Ocean Observatories"

    E-Print Network [OSTI]

    Boss, Emmanuel S.

    /JPSS ­ UAV ­ Ocean optics, Biological ­ Laser penetration New opportunity · Insitu Sensors ­ (Gliders"Towards Optics-Based Measurements in Ocean Observatories" "Ocean Observatories Contributions to Ocean Models and Data Assimilation For Ecosystems" Ocean Optics 2012 Glasgow Scotland Robert Arnone

  10. Sediment permeability, distribution, and influence on fluxes in oceanic basement

    E-Print Network [OSTI]

    Fisher, Andrew

    6 Sediment permeability, distribution, and influence on fluxes in oceanic basement Glenn A. Spinelli, Emily R. Giambalvo, and Andrew T. Fisher 6.1 Introduction Sediments blanketing oceanic igneous basement rocks control the communication between fluid within the crust and the oceans. Seafloor sediments

  11. Compound-Specific Radiocarbon Analyses of Phospholipid Fatty Acids and n-Alkanes in Ocean Sediments

    E-Print Network [OSTI]

    2010-01-01

    Monica Basin surface sediment: a model based on compound-ACIDS AND n-ALKANES IN OCEAN SEDIMENTS Ellen R M Druffel 1 •organic matter in ocean sediments from the northeast Pacific

  12.  COMPOUND-SPECIFIC RADIOCARBON ANALYSES OF PHOSPHOLIPID FATTY ACIDS AND n -ALKANES IN OCEAN SEDIMENTS

    E-Print Network [OSTI]

    2010-01-01

    Monica Basin surface sediment: a model based on compound-ACIDS AND n-ALKANES IN OCEAN SEDIMENTS Ellen R M Druffel 1 •organic matter in ocean sediments from the northeast Pacific

  13. Gas production potential of disperse low-saturation hydrate accumulations in oceanic sediments

    E-Print Network [OSTI]

    Moridis, George J.; Sloan, E. Dendy

    2006-01-01

    bound gas in marine sediments: how much is really out there?methane hydrate in ocean sediment. Energy & Fuels 2005: 19:Accumulations in Oceanic Sediments George J. Moridis 1 and

  14. Changes in ocean properties associated with Hurricane Isabel R. GAUTAM{, R. P. SINGH*{{ and M. KAFATOS{

    E-Print Network [OSTI]

    Singh, Ramesh P.

    Changes in ocean properties associated with Hurricane Isabel R. GAUTAM{, R. P. SINGH*{{ and M natural hazards (Kundu et al. 2001, Singh et al. 2002). Natural hazards cause a lot of damage

  15. UNCORRECTED Grid geometry effects on convection in ocean climate models

    E-Print Network [OSTI]

    Kuhlbrodt, Till

    is the 12 improvement of convection parameterization schemes, but the question of grid geometry also plays.elsevier.com/locate/omodol OCEMOD 100 No. of Pages 18, DTD = 4.3.1 28 August 2003 Type ARTICLE IN PRESS #12;UNCORRECTED PROOF 26 1 density gradient actually vanishes, one observes a strong vertical turbulent mixing to 32 depths of 2 km

  16. The change in oceanic O2 inventory associated with recent global warming

    E-Print Network [OSTI]

    Keeling, Ralph

    The change in oceanic O2 inventory associated with recent global warming Ralph F. Keeling, 2002 (received for review September 24, 2001) Oceans general circulation models predict that global warming may cause a decrease in the oceanic O2 inventory and an associated O2 outgassing. An independent

  17. Improved irradiances for use in ocean heating, primary production, and photo-oxidation calculations

    E-Print Network [OSTI]

    Boss, Emmanuel S.

    Improved irradiances for use in ocean heating, primary production, and photo-oxidation calculations- surface, broadband, daily averaged irradiance or photosynthetically available radiation (PAR) values or quantum units to in-water net irradiance, as needed for calculations of water heating, and to in- water

  18. Summer Courses in Ocean Optics and Biogeochemistry: "Monitoring the Oceans with Coastal Observatories" and

    E-Print Network [OSTI]

    Boss, Emmanuel S.

    Summer Courses in Ocean Optics and Biogeochemistry: "Monitoring the Oceans with Coastal integration of optical approaches into oceanographic research in general. OBJECTIVES These two courses created and optical oceanography and ocean color remote sensing to learn the fundamentals of optics in a coastal

  19. Estimation of light penetration, and horizontal and vertical visibility in oceanic and coastal waters from surface reflectance

    E-Print Network [OSTI]

    Babin, Marcel

    Estimation of light penetration, and horizontal and vertical visibility in oceanic and coastal penetration, and horizontal and vertical visibility in oceanic and coastal waters from surface reflectance, J. The algorithms are found to be valid both in coastal and oceanic waters, and largely insensitive to regional

  20. Method and apparatus for efficient injection of CO2 in oceans

    DOE Patents [OSTI]

    West, Olivia R.; Tsouris, Constantinos; Liang, Liyuan

    2003-07-29

    A liquid CO.sub.2 injection system produces a negatively buoyant consolidated stream of liquid CO.sub.2, CO.sub.2 hydrate, and water that sinks upon release at ocean depths in the range of 700-1500 m. In this approach, seawater at a predetermined ocean depth is mixed with the liquid CO.sub.2 stream before release into the ocean. Because mixing is conducted at depths where pressures and temperatures are suitable for CO.sub.2 hydrate formation, the consolidated stream issuing from the injector is negatively buoyant, and comprises mixed CO.sub.2 -hydrate/CO.sub.2 -liquid/water phases. The "sinking" characteristic of the produced stream will prolong the metastability of CO.sub.2 ocean sequestration by reducing the CO.sub.2 dissolution rate into water. Furthermore, the deeper the CO.sub.2 hydrate stream sinks after injection, the more stable it becomes internally, the deeper it is dissolved, and the more dispersed is the resulting CO.sub.2 plume. These factors increase efficiency, increase the residence time of CO2 in the ocean, and decrease the cost of CO.sub.2 sequestration while reducing deleterious impacts of free CO.sub.2 gas in ocean water.

  1. Partial Observers

    E-Print Network [OSTI]

    Thomas Marlow

    2006-10-20

    We attempt to dissolve the measurement problem using an anthropic principle which allows us to invoke rational observers. We argue that the key feature of such observers is that they are rational (we need not care whether they are `classical' or `macroscopic' for example) and thus, since quantum theory can be expressed as a rational theory of probabilistic inference, the measurement problem is not a problem.

  2. Parametric Excitation of Internal Gravity Waves in Ocean and Atmosphere as Precursors of Strong Earthquakes and Tsunami

    E-Print Network [OSTI]

    Chefranov, Sergey G

    2013-01-01

    The condition of internal gravity waves (IGW) parametric excitation in the rotating fluid layer heated from above, with the layer vibration along the vertical axis or with periodic modulation in time of the vertical temperature distribution, is obtained. We show the dual role of the molecular dissipative effects that may lead not only to the wave oscillations damping, but also to emergence of hydrodynamic dissipative instability (DI) in some frequency band of IGW. This DI also may take place for the localized in horizontal plane tornado-like disturbances, horizontal scale of which does not exceed the character vertical scale for the fluid layer of the finite depth. Investigated parametric resonance mechanism of IGW generation in ocean and atmosphere during and before earthquakes allows monitoring of such waves (with double period with respect to the period of vibration or temperature gradient modulation) as precursors of these devastating phenomena.

  3. Mechanisms Leading to Co-Existence of Gas Hydrate in Ocean Sediments [Part 2 of 2

    SciTech Connect (OSTI)

    Bryant, Steven; Juanes, Ruben

    2011-12-31

    In this project we have sought to explain the co-existence of gas and hydrate phases in sediments within the gas hydrate stability zone. We have focused on the gas/brine interface at the scale of individual grains in the sediment. The capillary forces associated with a gas/brine interface play a dominant role in many processes that occur in the pores of sediments and sedimentary rocks. The mechanical forces associated with the same interface can lead to fracture initiation and propagation in hydrate-bearing sediments. Thus the unifying theme of the research reported here is that pore scale phenomena are key to understanding large scale phenomena in hydrate-bearing sediments whenever a free gas phase is present. Our analysis of pore-scale phenomena in this project has delineated three regimes that govern processes in which the gas phase pressure is increasing: fracturing, capillary fingering and viscous fingering. These regimes are characterized by different morphology of the region invaded by the gas. On the other hand when the gas phase pressure is decreasing, the corresponding regimes are capillary fingering and compaction. In this project, we studied all these regimes except compaction. Many processes of interest in hydrate-bearing sediments can be better understood when placed in the context of the appropriate regime. For example, hydrate formation in sub-permafrost sediments falls in the capillary fingering regime, whereas gas invasion into ocean sediments is likely to fall into the fracturing regime. Our research provides insight into the mechanisms by which gas reservoirs are converted to hydrate as the base of the gas hydrate stability zone descends through the reservoir. If the reservoir was no longer being charged, then variation in grain size distribution within the reservoir explain hydrate saturation profiles such as that at Mt. Elbert, where sand-rich intervals containing little hydrate are interspersed between intervals containing large hydrate saturations. Large volumes (of order one pore volume) of gaseous and aqueous phases must be transported into the gas hydrate stability zone. The driver for this transport is the pressure sink induced by a reduction in occupied pore volume that accompanies the formation of hydrate from gas and water. Pore-scale imbibition models and bed-scale multiphase flow models indicate that the rate-limiting step in converting gas to hydrate is the supply of water to the hydrate stability zone. Moreover, the water supply rate is controlled by capillarity-driven flux for conditions typical of the Alaska North Slope. A meter-scale laboratory experiment confirms that significant volumes of fluid phases move into the hydrate stability zone and that capillarity is essential for the water flux. The model shows that without capillarity-driven flux, large saturations of hydrate cannot form. The observations of thick zones of large saturation at Mallik and Mt Elbert thus suggest that the primary control on these systems is the rate of transport of gaseous and aqueous phases, driven by the pressure sink at the base of the gas hydrate stability zone. A key finding of our project is the elucidation of ?capillary fracturing? as a dominant gas transport mechanism in low-permeability media. We initially investigate this phenomenon by means of grain-scale simulations in which we extended a discrete element mechanics code (PFC, by Itasca) to incorporate the dynamics of first singlephase and then multiphase flow. A reductionist model on a square lattice allows us to determine some of the fundamental dependencies of the mode of gas invasion (capillary fingering, viscous fingering, and fracturing) on the parameters of the system. We then show that the morphology of the gas-invaded region exerts a fundamental control on the fabric of methane hydrate formation, and on the overpressures caused by methane hydrate dissociation. We demonstrate the existence of the different invasion regimes by means of controlled laboratory experiments in a radial cell. We collapse the behavior in the form of a phase dia

  4. Mechanisms Leading to Co-Existence of Gas Hydrate in Ocean Sediments [Part 1 of 2

    SciTech Connect (OSTI)

    Bryant, Steven; Juanes, Ruben

    2011-12-31

    In this project we have sought to explain the co-existence of gas and hydrate phases in sediments within the gas hydrate stability zone. We have focused on the gas/brine interface at the scale of individual grains in the sediment. The capillary forces associated with a gas/brine interface play a dominant role in many processes that occur in the pores of sediments and sedimentary rocks. The mechanical forces associated with the same interface can lead to fracture initiation and propagation in hydrate-bearing sediments. Thus the unifying theme of the research reported here is that pore scale phenomena are key to understanding large scale phenomena in hydrate-bearing sediments whenever a free gas phase is present. Our analysis of pore-scale phenomena in this project has delineated three regimes that govern processes in which the gas phase pressure is increasing: fracturing, capillary fingering and viscous fingering. These regimes are characterized by different morphology of the region invaded by the gas. On the other hand when the gas phase pressure is decreasing, the corresponding regimes are capillary fingering and compaction. In this project, we studied all these regimes except compaction. Many processes of interest in hydrate-bearing sediments can be better understood when placed in the context of the appropriate regime. For example, hydrate formation in sub-permafrost sediments falls in the capillary fingering regime, whereas gas invasion into ocean sediments is likely to fall into the fracturing regime. Our research provides insight into the mechanisms by which gas reservoirs are converted to hydrate as the base of the gas hydrate stability zone descends through the reservoir. If the reservoir was no longer being charged, then variation in grain size distribution within the reservoir explain hydrate saturation profiles such as that at Mt. Elbert, where sand-rich intervals containing little hydrate are interspersed between intervals containing large hydrate saturations. Large volumes (of order one pore volume) of gaseous and aqueous phases must be transported into the gas hydrate stability zone. The driver for this transport is the pressure sink induced by a reduction in occupied pore volume that accompanies the formation of hydrate from gas and water. Pore-scale imbibition models and bed-scale multiphase flow models indicate that the rate-limiting step in converting gas to hydrate is the supply of water to the hydrate stability zone. Moreover, the water supply rate is controlled by capillarity-driven flux for conditions typical of the Alaska North Slope. A meter-scale laboratory experiment confirms that significant volumes of fluid phases move into the hydrate stability zone and that capillarity is essential for the water flux. The model shows that without capillarity-driven flux, large saturations of hydrate cannot form. The observations of thick zones of large saturation at Mallik and Mt Elbert thus suggest that the primary control on these systems is the rate of transport of gaseous and aqueous phases, driven by the pressure sink at the base of the gas hydrate stability zone. A key finding of our project is the elucidation of ?capillary fracturing? as a dominant gas transport mechanism in low-permeability media. We initially investigate this phenomenon by means of grain-scale simulations in which we extended a discrete element mechanics code (PFC, by Itasca) to incorporate the dynamics of first single-phase and then multiphase flow. A reductionist model on a square lattice allows us to determine some of the fundamental dependencies of the mode of gas invasion (capillary fingering, viscous fingering, and fracturing) on the parameters of the system. We then show that the morphology of the gas-invaded region exerts a fundamental control on the fabric of methane hydrate formation, and on the overpressures caused by methane hydrate dissociation. We demonstrate the existence of the different invasion regimes by means of controlled laboratory experiments in a radial cell. We collapse the behavior in the form of a phase di

  5. Geo-neutrino Observation

    SciTech Connect (OSTI)

    Dye, S. T.; Alderman, M.; Batygov, M.; Learned, J. G.; Matsuno, S.; Mahoney, J. M.; Pakvasa, S.; Rosen, M.; Smith, S.; Varner, G.; McDonough, W. F.

    2009-12-17

    Observations of geo-neutrinos measure radiogenic heat production within the earth, providing information on the thermal history and dynamic processes of the mantle. Two detectors currently observe geo-neutrinos from underground locations. Other detection projects in various stages of development include a deep ocean observatory. This paper presents the current status of geo-neutrino observation and describes the scientific capabilities of the deep ocean observatory, with emphasis on geology and neutrino physics.

  6. Hot Pot Field Observations

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

    Lane, Michael

    2013-06-28

    Map of field observations including depressions, springs, evidence of former springs, travertine terraces and vegetation patterns. Map also contains interpretation of possible spring alignments.

  7. Hot Pot Field Observations

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

    Lane, Michael

    Map of field observations including depressions, springs, evidence of former springs, travertine terraces and vegetation patterns. Map also contains interpretation of possible spring alignments.

  8. Atomic Collapse Observed

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

    Scientists Observe Atomic Collapse State Quantum Mechanics Prediction Confirmed in Graphene Using NERSC's Hopper April 26, 2013 | Tags: Hopper, Materials Science Contact: Linda...

  9. Physical observability of horizons

    E-Print Network [OSTI]

    Matt Visser

    2014-11-25

    Event horizons are (generically) not physically observable. In contrast, apparent horizons (and the closely related trapping horizons) are generically physically observable --- in the sense that they can be detected by observers working in finite-size regions of spacetime. Consequently event horizons are inappropriate tools for defining astrophysical black holes, or indeed for defining any notion of evolving}black hole, (evolving either due to accretion or Hawking radiation). The only situation in which an event horizon becomes physically observable is for the very highly idealized stationary or static black holes, when the event horizon is a Killing horizon which is degenerate with the apparent and trapping horizons; and then it is the physical observability of the apparent/trapping horizons that is fundamental --- the event horizon merely comes along for the ride.

  10. Physical observability of horizons

    E-Print Network [OSTI]

    Visser, Matt

    2014-01-01

    Event horizons are (generically) not physically observable. In contrast, apparent horizons (and the closely related trapping horizons) are generically physically observable --- in the sense that they can be detected by observers working in finite-size regions of spacetime. Consequently event horizons are inappropriate tools for defining astrophysical black holes, or indeed for defining any notion of evolving}black hole, (evolving either due to accretion or Hawking radiation). The only situation in which an event horizon becomes physically observable is for the very highly idealized stationary or static black holes, when the event horizon is a Killing horizon which is degenerate with the apparent and trapping horizons; and then it is the physical observability of the apparent/trapping horizons that is fundamental --- the event horizon merely comes along for the ride.

  11. Observables on Quantum Structures

    E-Print Network [OSTI]

    Anatolij Dvure?enskij; Mária Kuková

    2012-04-29

    An observable on a quantum structure is any $\\sigma$-homomorphism of quantum structures from the Borel $\\sigma$-algebra into the quantum structure. We show that our partial information on an observable known only for all intervals of the form $(-\\infty,t)$ is sufficient to determine uniquely the whole observable defined on quantum structures like $\\sigma$-MV-algebras, $\\sigma$-effect algebras, Boolean $\\sigma$-algebras, monotone $\\sigma$-complete effect algebras with the Riesz Decomposition Property, the effect algebra of effect operators of a Hilbert space, and a system of functions, and an effect-tribe.

  12. MARS OBSERVER Mission Failure

    E-Print Network [OSTI]

    Rhoads, James

    of Mars Observer Mission Failure.. ................... D-12 a. Most Probable Cause: Leakage of NT0 Through Check Valves .................................................................. D-14 b. Potential Cause: Pressure Regulator Failure....................... D-28 c. Potential Cause: Failure of a Pyro Valve Charge

  13. Air Observe System

    E-Print Network [OSTI]

    Alexander Bolonkin

    2007-01-10

    This manuscript contains a description and basic principles for observing inaccessible areas using low cost, easily deployed equipment. The basic premise is to suspend a tiny video camera at an altitude of 10 - 200 meters over the area to be surveyed. The TV camera supports at altitude by wind or balloon. The technical challenges regard the means by which the camera is suspended. Such a system may be used by military or police forces or by civil authorities for rescue missions or assessment of natural disasters. The method may be further developed for military applications by integrating the surveillance task with deployment of munitions. Key words: air observer, air suspended system, low altitude video observer.

  14. Quantum Mechanics Without Observers

    E-Print Network [OSTI]

    W. H. Sulis

    2013-03-03

    The measurement problem and the role of observers have plagued quantum mechanics since its conception. Attempts to resolve these have introduced anthropomorphic or non-realist notions into physics. A shift of perspective based upon process theory and utilizing methods from combinatorial games, interpolation theory and complex systems theory results in a novel realist version of quantum mechanics incorporating quasi-local, nondeterministic hidden variables that are compatible with the no-hidden variable theorems and relativistic invariance, and reproduce the standard results of quantum mechanics to a high degree of accuracy without invoking observers.

  15. Global Warming Observations

    E-Print Network [OSTI]

    Schofield, Jeremy

    Global Warming Observations: 1. Global temperature has been gradually rising in recent years #15 in range 8000 12000 nm { CFC's, methane and N 2 O important for global warming even though concentra- tions in concentration of \\greenhouse gases" like CO 2 What determines global temperature? Energy budget of earth: 1

  16. Observations of Exoplanet Atmospheres

    E-Print Network [OSTI]

    Crossfield, Ian J M

    2015-01-01

    Detailed characterization of an extrasolar planet's atmosphere provides the best hope for distinguishing the makeup of its outer layers, and the only hope for understanding the interplay between initial composition, chemistry, dynamics & circulation, and disequilibrium processes. In recent years, some areas have seen rapid progress while developments in others have come more slowly and/or have been hotly contested. This article gives an observer's perspective on the current understanding of extrasolar planet atmospheres prior to the considerable advances expected from the next generation of observing facilities. Atmospheric processes of both transiting and directly-imaged planets are discussed, including molecular and atomic abundances, cloud properties, thermal structure, and planetary energy budgets. In the future we can expect a continuing and accelerating stream of new discoveries, which will fuel the ongoing exoplanet revolution for many years to come.

  17. Observable primordial vector modes

    E-Print Network [OSTI]

    Antony Lewis

    2004-06-04

    Primordial vector modes describe vortical fluid perturbations in the early universe. A regular solution exists with constant non-zero radiation vorticities on super-horizon scales. Baryons are tightly coupled to the photons, and the baryon velocity only decays by an order unity factor by recombination, leading to an observable CMB anisotropy signature via the Doppler effect. There is also a large B-mode CMB polarization signal, with significant power on scales larger than l~2000. This B-mode signature is distinct from that expected from tensor modes or gravitational lensing, and makes a primordial vector to scalar mode power ratio ~10^(-6) detectable. Future observations aimed at detecting large scale B-modes from gravitational waves will also be sensitive to regular vector modes at around this level.

  18. Observations on European Agriculture. 

    E-Print Network [OSTI]

    Fraps, G. S. (George Stronach)

    1911-01-01

    AS ACKICUL-I-uRAL EXPE RIMENT STATIONS bLLETIN No. 14-1 DECEMBER, 1911 Division of Chemistry Observations on European Agriculture BY G. S. FRAPS, Chemist 0 Postoffice : CULLEGE STATION; TEXAS AUSTIN. TEXAS I AUSTIN PRINTING CO:. PRINTERS... ............................................... and Conclusions 35 [Blank Page in Original Bulletin] rrvations on European Agriculture By C. S. FRAPS ie object of this Bulletin is to present such abservadons on :ulture in Europe as may offer suggestions of value to Texas - :ulturists. The writer...

  19. Fluctuations of fragment observables

    E-Print Network [OSTI]

    F. Gulminelli; M. D'Agostino

    2006-11-09

    This contribution presents a review of our present theoretical as well as experimental knowledge of different fluctuation observables relevant to nuclear multifragmentation. The possible connection between the presence of a fluctuation peak and the occurrence of a phase transition or a critical phenomenon is critically analyzed. Many different phenomena can lead both to the creation and to the suppression of a fluctuation peak. In particular, the role of constraints due to conservation laws and to data sorting is shown to be essential. From the experimental point of view, a comparison of the available fragmentation data reveals that there is a good agreement between different data sets of basic fluctuation observables, if the fragmenting source is of comparable size. This compatibility suggests that the fragmentation process is largely independent of the reaction mechanism (central versus peripheral collisions, symmetric versus asymmetric systems, light ions versus heavy ion induced reactions). Configurational energy fluctuations, that may give important information on the heat capacity of the fragmenting system at the freeze out stage, are not fully compatible among different data sets and require further analysis to properly account for Coulomb effects and secondary decays. Some basic theoretical questions, concerning the interplay between the dynamics of the collision and the fragmentation process, and the cluster definition in dense and hot media, are still open and are addressed at the end of the paper. A comparison with realistic models and/or a quantitative analysis of the fluctuation properties will be needed to clarify in the next future the nature of the transition observed from compound nucleus evaporation to multi-fragment production.

  20. ARM Observations Projected

    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 OutreachProductswsicloudwsicloudden Documentation Data Management Facility PlotsProductsObservations Projected

  1. Observations of Accreting Pulsars

    E-Print Network [OSTI]

    Lars Bildsten; Deepto Chakrabarty; John Chiu; Mark H. Finger; Danny T. Koh; Robert W. Nelson; Thomas A. Prince; Bradley C. Rubin; D. Matthew Scott; Mark Stollberg; Brian A. Vaughan; Colleen A. Wilson; Robert B. Wilson

    1997-07-22

    We summarize five years of continuous monitoring of accretion-powered pulsars with the Burst and Transient Source Experiment (BATSE) on the Compton Gamma Ray Observatory. Our 20-70 keV observations have determined or refined the orbital parameters of 13 binaries, discovered 5 new transient accreting pulsars, measured the pulsed flux history during outbursts of 12 transients (GRO J1744-28, 4U 0115+634, GRO J1750-27, GS 0834-430, 2S 1417-624, GRO J1948+32, EXO 2030+375, GRO J1008-57, A 0535+26, GRO J2058+42, 4U 1145-619 and A 1118-616), and also measured the accretion torque history of during outbursts of 6 of those transients whose orbital parameters were also known. We have also continuously measured the pulsed flux and spin frequency for eight persistently accreting pulsars (Her X-1, Cen X-3, Vela X-1, OAO 1657-415, GX 301-2, 4U 1626-67, 4U 1538-52, and GX 1+4). Because of their continuity and uniformity over a long baseline, BATSE observations have provided new insights into the long-term behavior of accreting magnetic stars. We have found that all accreting pulsars show stochastic variations in their spin frequencies and luminosities, including those displaying secular spin-up or spin-down on long time scales, blurring the conventional distinction between disk-fed and wind-fed binaries. Pulsed flux and accretion torque are strongly correlated in outbursts of transient accreting pulsars, but uncorrelated, or even anticorrelated, in persistent sources.

  2. Physically Observable Cryptography Silvio Micali

    E-Print Network [OSTI]

    Reyzin, Leonid

    Physically Observable Cryptography Silvio Micali Leonid Reyzin November 29, 2003 Abstract.) inherent in the physical execution of any cryptographic algorithm. Such "physical observation attacks mathematically impregnable systems. The great practicality and the inherent availability of physical attacks

  3. State observer for synchronous motors

    DOE Patents [OSTI]

    Lang, Jeffrey H. (Waltham, MA)

    1994-03-22

    A state observer driven by measurements of phase voltages and currents for estimating the angular orientation of a rotor of a synchronous motor such as a variable reluctance motor (VRM). Phase voltages and currents are detected and serve as inputs to a state observer. The state observer includes a mathematical model of the electromechanical operation of the synchronous motor. The characteristics of the state observer are selected so that the observer estimates converge to the actual rotor angular orientation and velocity, winding phase flux linkages or currents.

  4. Observation

    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 wouldMass mapSpeeding access to scienceSpeedingLightweight MaterialsGas and OilPublictearing

  5. Observation

    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 wouldMass mapSpeeding access to scienceSpeedingLightweight MaterialsGas and

  6. Observation

    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 aLEDSpeeding accessSpeeding access

  7. NS&T MANAGEMENT OBSERVATIONS

    SciTech Connect (OSTI)

    Gianotto, David

    2014-06-01

    The INL Management Observation Program (MOP) is designed to improve managers and supervisors understanding of work being performed by employees and the barriers impacting their success. The MOP also increases workers understanding of managements’ expectations as they relate to safety, security, quality, and work performance. Management observations (observations) are designed to improve the relationship and trust between employees and managers through increased engagement and interactions between managers and researchers in the field. As part of continuous improvement, NS&T management took initiative to focus on the participation and quality of observations in FY 14. This quarterly report is intended to (a) summarize the participation and quality of management’s observations, (b) assess observations for commonalities or trends related to facility or process barriers impacting research, and (c) provide feedback and make recommendations for improvements NS&T’s MOP.

  8. NS&T Management Observations

    SciTech Connect (OSTI)

    Gianotto, David

    2014-09-01

    The INL Management Observation Program (MOP) is designed to improve managers and supervisors understanding of work being performed by employees and the barriers impacting their success. The MOP also increases workers understanding of managements’ expectations as they relate to safety, security, quality, and work performance. Management observations (observations) are designed to improve the relationship and trust between employees and managers through increased engagement and interactions between managers and researchers in the field. As part of continuous improvement, NS&T management took initiative to focus on the participation and quality of observations in FY 14. This quarterly report is intended to (a) summarize the participation and quality of management’s observations, (b) assess observations for commonalities or trends related to facility or process barriers impacting research, and (c) provide feedback and make recommendations for improvements NS&T’s MOP.

  9. Accelerated Expansion: Theory and Observations

    E-Print Network [OSTI]

    David Polarski

    2001-09-20

    The present paradigm in cosmology is the usual Big-Bang Cosmology in which two stages of accelerated expansion are incorporated: the inflationary phase in the very early universe which produces the classical inhomogeneities observed in the universe, and a second stage of acceleration at the present time as the latest Supernovae observations seem to imply. Both stages could be produced by a scalar field and observations will strongly constrain the microscopic lagrangian of any proposed model.

  10. Loop quantum gravity and observations

    E-Print Network [OSTI]

    A. Barrau; J. Grain

    2015-10-28

    Quantum gravity has long been thought to be completely decoupled from experiments or observations. Although it is true that smoking guns are still missing, there are now serious hopes that quantum gravity phenomena might be tested. We review here some possible ways to observe loop quantum gravity effects either in the framework of cosmology or in astroparticle physics.

  11. Observational Study PAUL R. ROSENBAUM

    E-Print Network [OSTI]

    George, Edward I.

    . Howell John Wiley & Sons, Ltd, Chichester, 2005 #12;Observational Study Observational Studies Defined describing the subjects before treatment. As a consequence, random assignment tends to make the groups comparable both in terms of measured char- acteristics and characteristics that were not or could

  12. Passive States for Essential Observers

    E-Print Network [OSTI]

    Robert Strich

    2008-01-23

    The aim of this note is to present a unified approach to the results given in \\cite{bb99} and \\cite{bs04} which also covers examples of models not presented in these two papers (e.g. $d$-dimensional Minkowski space-time for $d\\geq 3$). Assuming that a state is passive for an observer travelling along certain (essential) worldlines, we show that this state is invariant under the isometry group, is a KMS-state for the observer at a temperature uniquely determined by the structure constants of the Lie algebra involved and fulfills (a variant of) the Reeh-Schlieder property. Also the modular objects associated to such a state and the observable algebra of an observer are computed and a version of weak locality is examined.

  13. Jet observables without jet algorithms

    E-Print Network [OSTI]

    Bertolini, Daniele

    We introduce a new class of event shapes to characterize the jet-like structure of an event. Like traditional event shapes, our observables are infrared/collinear safe and involve a sum over all hadrons in an event, but ...

  14. Baryon Resonances Observed at BES

    E-Print Network [OSTI]

    B. S. Zou

    2008-02-01

    The $\\psi$ decays provide a novel way to explore baryon spectroscopy and baryon structure. The baryon resonances observed from $\\psi$ decays at BES are reviewed. The implications and prospects at upgraded BESIII/BEPCII are discussed.

  15. Observations & Thoughts on Controller Assessment &

    E-Print Network [OSTI]

    Harris, Thomas J.

    & Assessment Design & interpretation of monitoring & assessment methods cannot be divorced from processObservations & Thoughts on Controller Assessment & Performance Monitoring T.J. Harris Queen's University harrist@post.queensu.ca Control Systems 2004 #12;Acknowledge Contributions of NSERC Imperial Oil

  16. Observing the next galactic supernova

    SciTech Connect (OSTI)

    Adams, Scott M.; Kochanek, C. S.; Beacom, John F.; Stanek, K. Z. [Department of Astronomy, The Ohio State University, 140 West 18th Avenue, Columbus, OH 43210 (United States); Vagins, Mark R. [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)

    2013-12-01

    No supernova (SN) in the Milky Way has been observed since the invention of the optical telescope, instruments for other wavelengths, neutrino detectors, or gravitational wave observatories. It would be a tragedy to miss the opportunity to fully characterize the next one. To aid preparations for its observations, we model the distance, extinction, and magnitude probability distributions of a successful Galactic core-collapse supernova (ccSN), its shock breakout radiation, and its massive star progenitor. We find, at very high probability (? 100%), that the next Galactic SN will easily be detectable in the near-IR and that near-IR photometry of the progenitor star very likely (? 92%) already exists in the Two Micron All Sky Survey. Most ccSNe (98%) will be easily observed in the optical, but a significant fraction (43%) will lack observations of the progenitor due to a combination of survey sensitivity and confusion. If neutrino detection experiments can quickly disseminate a likely position (?3°), we show that a modestly priced IR camera system can probably detect the shock breakout radiation pulse even in daytime (64% for the cheapest design). Neutrino experiments should seriously consider adding such systems, both for their scientific return and as an added and internal layer of protection against false triggers. We find that shock breakouts from failed ccSNe of red supergiants may be more observable than those of successful SNe due to their lower radiation temperatures. We review the process by which neutrinos from a Galactic ccSN would be detected and announced. We provide new information on the EGADS system and its potential for providing instant neutrino alerts. We also discuss the distance, extinction, and magnitude probability distributions for the next Galactic Type Ia supernova (SN Ia). Based on our modeled observability, we find a Galactic ccSN rate of 3.2{sub ?2.6}{sup +7.3} per century and a Galactic SN Ia rate of 1.4{sub ?0.8}{sup +1.4} per century for a total Galactic SN rate of 4.6{sub ?2.7}{sup +7.4} per century is needed to account for the SNe observed over the last millennium, which implies a Galactic star formation rate of 3.6{sub ?3.0}{sup +8.3} M {sub ?} yr{sup –1}.

  17. CX Lyrae 2008 Observing Campaign

    E-Print Network [OSTI]

    de Ponthiere, Pierre; Hambsch, Franz-Josef

    2012-01-01

    The Blazhko effect in CX Lyr has been reported for the first time by Le Borgne et al. (2007). The authors have pointed out that the Blazhko period was not evaluated accurately due to dataset scarcity. The possible period values announced were 128 or 227 days. A newly conducted four-month observing campaign in 2008 (fifty-nine observation nights) has provided fourteen times of maximum. From a period analysis of measured times of maximum, a Blazhko period of 62 +/- 2 days can be suggested. However, the present dataset is still not densely sampled enough to exclude that the measured period is still a modulation of the real Blazhko period. Indeed the shape of the (O-C) curve does not repeat itself exactly during the campaign duration.

  18. RHESSI observation of flare elements

    E-Print Network [OSTI]

    Paolo C. Grigis; Arnold O. Benz

    2006-02-14

    RHESSI observations of elementary flare bursts are presented. These solar flare elements are distinct emission peaks of a duration of some tens of seconds present in the hard X-ray light curves. They are characterized by consistent soft-hard-soft spectral behavior, which can be described in a quantitative way and compared which predictions from acceleration models. A detailed analysis of hard X-ray images for an M5 class flare shows that elementary flare bursts do not occur at distinct locations, but as twin X-ray sources move smoothly along an arcade of magnetic loops. This observation apparently contradicts the predictions of standard translation invariant 2.5-dimensional reconnection models.

  19. Complete measurements of quantum observables

    E-Print Network [OSTI]

    Juha-Pekka Pellonpää

    2012-06-12

    We define a complete measurement of a quantum observable (POVM) as a measurement of the maximally refined version of the POVM. Complete measurements give information from the multiplicities of the measurement outcomes and can be viewed as state preparation procedures. We show that any POVM can be measured completely by using sequential measurements or maximally refinable instruments. Moreover, the ancillary space of a complete measurement can be chosen to be minimal.

  20. Infrared Observations of Galaxy Clusters

    E-Print Network [OSTI]

    David Elbaz

    1997-11-28

    This short paper reviews some of the results obtained from ISO observations (ISOCAM and ISOPHOT) on galaxy clusters: Chap.1: "Intracluster dust": new evidence for the presence of dust outside galaxies. Chap.2:"Mid-Infrared Emission of Galaxies" origin of the mid-IR emission. Chap.3:"Star Formation in Nearby Clusters" correlation of the 7 and 15 microns fluxes with the SFR. Chap.4:"Star Formation in z=0.2 Galaxy clusters" Study of the mid-IR emission of A1732 and A1689. Chap.5:"Star Formation in z>0.4 Galaxy clusters" Preliminary.

  1. Observation Wells | 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:Newberg, Oregon:OGE Energy Resources, IncInc JumpObamaObservation

  2. Magnetars: the physics behind observations

    E-Print Network [OSTI]

    Turolla, Roberto; Watts, Anna

    2015-01-01

    Magnetars are the strongest magnets in the present universe and the combination of extreme magnetic field, gravity and density makes them unique laboratories to probe current physical theories (from quantum electrodynamics to general relativity) in the strong field limit. Magnetars are observed as peculiar, burst--active X-ray pulsars, the Anomalous X-ray Pulsars (AXPs) and the Soft Gamma Repeaters (SGRs); the latter emitted also three "giant flares," extremely powerful events during which luminosities can reach up to 10^47 erg/s for about one second. The last five years have witnessed an explosion in magnetar research which has led, among other things, to the discovery of transient, or "outbursting," and "low-field" magnetars. Substantial progress has been made also on the theoretical side. Quite detailed models for explaining the magnetars' persistent X-ray emission, the properties of the bursts, the flux evolution in transient sources have been developed and confronted with observations. New insight on neu...

  3. Bayesian Inference for Radio Observations

    E-Print Network [OSTI]

    Lochner, Michelle; Zwart, Jonathan T L; Smirnov, Oleg; Bassett, Bruce A; Oozeer, Nadeem; Kunz, Martin

    2015-01-01

    (Abridged) New telescopes like the Square Kilometre Array (SKA) will push into a new sensitivity regime and expose systematics, such as direction-dependent effects, that could previously be ignored. Current methods for handling such systematics rely on alternating best estimates of instrumental calibration and models of the underlying sky, which can lead to inaccurate uncertainty estimates and biased results because such methods ignore any correlations between parameters. These deconvolution algorithms produce a single image that is assumed to be a true representation of the sky, when in fact it is just one realisation of an infinite ensemble of images compatible with the noise in the data. In contrast, here we report a Bayesian formalism that simultaneously infers both systematics and science. Our technique, Bayesian Inference for Radio Observations (BIRO), determines all parameters directly from the raw data, bypassing image-making entirely, by sampling from the joint posterior probability distribution. Thi...

  4. Aerosol Observing System (AOS) Handbook

    SciTech Connect (OSTI)

    Jefferson, A

    2011-01-17

    The Aerosol Observing System (AOS) is a suite of in situ surface measurements of aerosol optical and cloud-forming properties. The instruments measure aerosol properties that influence the earth’s radiative balance. The primary optical measurements are those of the aerosol scattering and absorption coefficients as a function of particle size and radiation wavelength and cloud condensation nuclei (CCN) measurements as a function of percent supersaturation. Additional measurements include those of the particle number concentration and scattering hygroscopic growth. Aerosol optical measurements are useful for calculating parameters used in radiative forcing calculations such as the aerosol single-scattering albedo, asymmetry parameter, mass scattering efficiency, and hygroscopic growth. CCN measurements are important in cloud microphysical models to predict droplet formation.

  5. Comet tail formation: Giotto observations

    SciTech Connect (OSTI)

    Wilken, B.; Jockers, K.; Johnstone, A.; Coates, A.; Heath, J.; Formisano, V.; Amata, E.; Winningham, J.D.; Thomsen, M.; Bryant, D.A.

    1986-01-01

    The process of mass loading of the solar wind by cometary ions, which forms comet tails, has been observed throughout the coma of comet Halley. Three distinct regimes were found where the nature of the energy and momentum coupling between solar wind and cometary ions is different. Outside the bow shock, where there is little angular scattering of the freshly ionized particles, the coupling is described by the simple pickup trajectory and the energy is controlled by the angle between the flow and the magnetic field. Just inside the bow shock, there is considerable scattering accompanied by another acceleration process which raises some particle energies well above the straightforward pickup value. Finally, closer to the nucleus, the amount of scattering decreases and the coupling is once more controlled by the magnetic field direction. 4 refs., 3 figs.

  6. Automated Surface Observing System: Standby Power Options

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

    contained group of sensors and data gathering equipment that produces an automated weather observation * Weather observations support aviation, climate data, non government...

  7. Unsuspected Pulmonary Embolism in Observation Unit Patients

    E-Print Network [OSTI]

    Limkakeng, Alexander T.; Glickman, Seth W; Cairns, Charles B; Chandra, Abhinav

    2009-01-01

    department observation unit. Emerg Med Clin North Am. 2001;ED) managed acute care unit on ED overcrowding and emergencyof a chest pain observation unit compared with routine care.

  8. Observed Communication in Distressed Couples' Interactions

    E-Print Network [OSTI]

    Baucom, Katherine Jane Williams

    2012-01-01

    A. (2011). Observed communication in couples two years afterA. (2011). Observed communication in couples two years afterA. (1996). The Communication Patterns Questionnaire: The

  9. First Observation of Plasmarons in Graphene

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

    First Observation of Plasmarons in Graphene First Observation of Plasmarons in Graphene Print Wednesday, 30 June 2010 00:00 An international team of scientists performing...

  10. ALASKA MARINE Alaska Marine Mammal Observer Program

    E-Print Network [OSTI]

    ALASKA MARINE MAMMAL PROGRAM 2012 #12;2012 Alaska Marine Mammal Observer Program Observer Manual Contents Section 1: The Alaska Marine Mammal Observer Program 1.0 Introduction 1.1 Marine Mammal Stock Program 1.5 Alaska Marine Mammal Observer Program Section 2: The Southeast Alaska Environment 2

  11. Comments on: Publication in Ocean Engineering

    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

  12. Sandia Energy - Publication in Ocean Engineering

    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 RoomPreservation of Fe(II)Geothermal Energy &WaterNewPhotoionizationPower TowersPricePublication

  13. Physically Observable Cryptography Silvio Micali # Leonid Reyzin +

    E-Print Network [OSTI]

    Reyzin, Leonid

    Physically Observable Cryptography Silvio Micali # Leonid Reyzin + November 29, 2003 Abstract.) inherent in the physical execution of any cryptographic algorithm. Such ``physical observation attacks mathematically impregnable systems. The great practicality and the inherent availability of physical attacks

  14. Discrimination of quantum observables using limited resources

    E-Print Network [OSTI]

    Mario Ziman; Teiko Heinosaari

    2008-02-18

    We address the problem of unambiguous discrimination and identification among quantum observables. We set a general framework and investigate in details the case of qubit observables. In particular, we show that perfect discrimination with two shots is possible only for sharp qubit observables (e.g. Stern-Gerlach apparatuses) associated with mutually orthogonal directions. We also show that for sharp qubit observables associated to nonorthogonal directions unambiguous discrimination with an inconclusive result is always possible.

  15. Observability and Computability in Physical Systems

    E-Print Network [OSTI]

    Subhash Kak

    2012-06-26

    This paper considers the relevance of the concepts of observability and computability in physical theory. Observability is related to verifiability which is essential for effective computing and as physical systems are computational systems it is important even where explicit computation is not the goal. Specifically, we examine two problems: observability and computability for quantum computing, and remote measurement of time and frequency.

  16. JAXA's Earth Observation Program Osamu Ochiai

    E-Print Network [OSTI]

    JAXA's Earth Observation Program Osamu Ochiai Japan Aerospace Exploration Agency #12;1 Disasters Health Energy Climate Water 1 Japanese Main Activities of Earth Observation Weather MTSAT (JMA) Eco Earth Observation Targets (JFY) 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018

  17. Observations of LSI+61303 with Swift

    E-Print Network [OSTI]

    J. Holder; A. Falcone; D. Morris

    2007-09-18

    The TeV emitting high-mass X-ray binary system LSI+61303 was observed with the Swift satellite from early September 2006 to early January 2007. Many of these observations were contemporaneous with TeV observations. The data consist of observations on 24 separate days with durations ranging between 700s and 4700s, and partially cover 4.5 orbital periods of the binary system. We present here an analysis of the 0.2 to 10keV X-ray data from the Swift-XRT instrument. Contemporaneous optical data from UVOT are also available.

  18. CCD Observing Manual 49 Bay State Road

    E-Print Network [OSTI]

    Zallen, Richard

    Stars 5.6. Supernovae/Novae Patrols 5.7. Designing Your Own: Using AAVSO VSX 6.0 Observing Techniques 6

  19. EA-1964: National Ecological Observation Network (NEON)

    Broader source: Energy.gov [DOE]

    The National Science Foundation (NSF) prepared an EA that evaluated potential environmental impacts of the proposed National Ecological Observation Network (NEON), a continental-scale network of...

  20. Observational Field Assessment of Invasiveness for

    E-Print Network [OSTI]

    Eucalyptus grandis observations..................................................... 13 Eucalyptus grandis), Eucalyptus grandis, African oil palm (Elaeis guineensis) and arboreal Leucaenas found on Oahu, Maui, Hawai

  1. Self-potential observations during hydraulic fracturing

    E-Print Network [OSTI]

    Moore, J R; Glaser, Steven D

    2007-01-01

    potential measurements during hydraulic fracturing of BunterSP response during hydraulic fracturing. Citation: Moore, J.observations during hydraulic fracturing, J. Geophys. Res. ,

  2. Self-potential observations during hydraulic fracturing

    E-Print Network [OSTI]

    Moore, J R; Glaser, Steven D

    2007-01-01

    during hydraulic fracturing of Bunter sandstones, Proc. NearSP response during hydraulic fracturing. Citation: Moore, J.observations during hydraulic fracturing, J. Geophys. Res. ,

  3. Cluster Observations with the South Pole Telescope

    E-Print Network [OSTI]

    Plagge, Thomas Jeffrey

    2009-01-01

    The South Pole Telescope during the last stages ofwater vapor at the South Pole relative to two otherSZ Survey Instrument . 3 The South Pole Telescope Observing

  4. Radioactivity in Precipitation: Methods and Observations from...

    Office of Environmental Management (EM)

    Radioactivity in Precipitation: Methods & Observations from Savannah River Site Dennis Jackson P.E. & Timothy Jannik - Savannah River National Laboratory Teresa Eddy - Savannah...

  5. Observation of Parametric Instability in Advanced LIGO

    E-Print Network [OSTI]

    Evans, Matthew; Fritschel, Peter; Miller, John; Barsotti, Lisa; Martynov, Denis; Brooks, Aidan; Coyne, Dennis; Abbott, Rich; Adhikari, Rana; Arai, Koji; Bork, Rolf; Kells, Bill; Rollins, Jameson; Smith-Lefebvre, Nicolas; Vajente, Gabriele; Yamamoto, Hiroaki; Derosa, Ryan; Effler, Anamaria; Kokeyama, Keiko; Betzweiser, Joseph; Frolov, Valera; Mullavey, Adam; O`Reilly, Brian; Dwyer, Sheila; Izumi, Kiwamu; Kawabe, Keita; Landry, Michael; Sigg, Daniel; Ballmer, Stefan; Massinger, Thomas J; Staley, Alexa; Mueller, Chris; Grote, Hartmut; Ward, Robert; King, Eleanor; Blair, David; Ju, Li; Zhao, Chunnong

    2015-01-01

    Parametric instabilities have long been studied as a potentially limiting effect in high-power interferometric gravitational wave detectors. Until now, however, these instabilities have never been observed in a kilometer-scale interferometer. In this work we describe the first observation of parametric instability in an Advanced LIGO detector, and the means by which it has been removed as a barrier to progress.

  6. NOS Integrated Ocean Observations Systems (IOOS)

    E-Print Network [OSTI]

    Observing Assets After Hurricane Sandy NOAA Award No. NA14NOS4830003 Report 05: 31 December 2014 Prepared Ocean Observing System when Hurricane Sandy passed through the region in October 2012. The objective lost during Sandy. The benefits of this work will increase the coverage and data quality of the surface

  7. NOS Integrated Ocean Observations Systems (IOOS)

    E-Print Network [OSTI]

    Observing Assets After Hurricane Sandy NOAA Award No. NA14NOS4830003 Report 04: 30 September 2014 Prepared Ocean Observing System when Hurricane Sandy passed through the region in October 2012. The objective lost during Sandy. The benefits of this work will increase the coverage and data quality of the surface

  8. NOS Integrated Ocean Observations Systems (IOOS)

    E-Print Network [OSTI]

    Observing Assets After Hurricane Sandy NOAA Award No. NA14NOS4830003 30 January 2014 Prepared for: NOAA IOOS Association Coastal Ocean Observing System when Hurricane Sandy passed through the region in October 2012 and ADCP assets lost during Sandy. The benefits of this work will increase the coverage and data quality

  9. NOS Integrated Ocean Observations Systems (IOOS)

    E-Print Network [OSTI]

    Observing Assets After Hurricane Sandy NOAA Award No. NA14NOS4830003 Report 01: 30 April 2014 Prepared for Ocean Observing System when Hurricane Sandy passed through the region in October 2012. The objective lost during Sandy. The benefits of this work will increase the coverage and data quality of the surface

  10. Observed Cosmological Redshifts Support Contracting Accelerating Universe

    E-Print Network [OSTI]

    Branislav Vlahovic

    2012-07-02

    The main argument that Universe is currently expanding is observed redshift increase by distance. However, this conclusion may not be correct, because cosmological redshift depends only on the scaling factors, the change in the size of the universe during the time of light propagation and is not related to the speed of observer or speed of the object emitting the light. An observer in expanding universe will measure the same redshift as observer in contracting universe with the same scaling. This was not taken into account in analysing the SN Ia data related to the universe acceleration. Possibility that universe may contract, but that the observed light is cosmologically redshifted allows for completely different set of cosmological parameters $\\Omega_M, \\Omega_{\\Lambda}$, including the solution $\\Omega_M=1, \\Omega_{\\Lambda}=0$. The contracting and in the same time accelerating universe explains observed deceleration and acceleration in SN Ia data, but also gives significantly larger value for the age of the universe, $t_0 = 24$ Gyr. This allows to reconsider classical cosmological models with $\\Lambda =0$. The contracting stage also may explain the observed association of high redshifted quasars to low redshifted galaxies.

  11. Quantum observables, Lie algebra homology and TQFT

    E-Print Network [OSTI]

    Albert Schwarz

    1999-04-25

    Let us consider a Lie (super)algebra $G$ spanned by $T_{\\alpha}$ where $T_{\\alpha}$ are quantum observables in BV-formalism. It is proved that for every tensor $c^{\\alpha_1...\\alpha_k}$ that determines a homology class of the Lie algebra $G$ the expression $c^{\\alpha_1...\\alpha_k}T_{\\alpha _1}...T_{\\alpha_k}$ is again a quantum observables. This theorem is used to construct quantum observables in BV sigma-model. We apply this construction to explain Kontsevich's results about the relation between homology of the Lie algebra of Hamiltonian vector fields and topological invariants of manifolds.

  12. Observation of Parametric Instability in Advanced LIGO

    E-Print Network [OSTI]

    Gras, Slawek

    Parametric instabilities have long been studied as a potentially limiting effect in high-power interferometric gravitational wave detectors. Until now, however, these instabilities have never been observed in a kilometer-scale ...

  13. Initial Helioseismic Observations by Hinode/SOT

    E-Print Network [OSTI]

    Takashi Sekii; Alexander G. Kosovichev; Junwei Zhao; Saku Tsuneta; Hiromoto Shibahashi; Thomas E. Berger; Kiyoshi Ichimoto; Yukio Katsukawa; Bruce W. Lites; Shin'ichi Nagata; Toshifumi Shimizu; Richard A. Shine; Yoshinori Suematsu; Theodore D. Tarbell; Alan M. Title

    2007-09-12

    Results from initial helioseismic observations by Solar Optical Telescope onboard Hinode are reported. It has been demonstrated that intensity oscillation data from Broadband Filter Imager can be used for various helioseismic analyses. The k-omega power spectra, as well as corresponding time-distance cross-correlation function that promises high-resolution time-distance analysis below 6-Mm travelling distance, were obtained for G-band and CaII-H data. Subsurface supergranular patterns have been observed from our first time-distance analysis. The results show that the solar oscillation spectrum is extended to much higher frequencies and wavenumbers, and the time-distance diagram is extended to much shorter travel distances and times than they were observed before, thus revealing great potential for high-resolution helioseismic observations from Hinode.

  14. Derivation of evolutionary payoffs from observable behavior

    E-Print Network [OSTI]

    Feigel, Alexander; Engel, Assaf

    2008-01-01

    Interpretation of animal behavior, especially as cooperative or selfish, is a challenge for evolutionary theory. Strategy of a competition should follow from corresponding Darwinian payoffs for the available behavioral options. The payoffs and decision making processes, however, are difficult to observe and quantify. Here we present a general method for the derivation of evolutionary payoffs from observable statistics of interactions. The method is applied to combat of male bowl and doily spiders, to predator inspection by sticklebacks and to territorial defense by lions, demonstrating animal behavior as a new type of game theoretical equilibrium. Games animals play may be derived unequivocally from their observable behavior, the reconstruction, however, can be subjected to fundamental limitations due to our inability to observe all information exchange mechanisms (communication).

  15. New York/Region Opinions Editorial Observer

    E-Print Network [OSTI]

    Pianka, Eric R.

    New York/Region Opinions Editorial Observer Grasping the Depth of Time as a First Step of us. The idea of such quantities of time is extremely new. Humans began to understand the true scale

  16. Observational learning in an uncertain world

    E-Print Network [OSTI]

    Acemoglu, Daron

    We study a model of observational learning in social networks in the presence of uncertainty about agents' type distributions. Each individual receives a private noisy signal about a payoff-relevant state of the world, and ...

  17. On the consistent use of Constructed Observables

    E-Print Network [OSTI]

    Trott, Michael

    2015-01-01

    We define "constructed observables" as relating experimental measurements to terms in a Lagrangian while simultaneously making assumptions about possible deviations from the Standard Model (SM), in other Lagrangian terms. Ensuring that the SM effective field theory (EFT) is constrained correctly when using constructed observables requires that their defining conditions are imposed on the EFT in a manner that is consistent with the equations of motion. Failing to do so can result in a "functionally redundant" operator basis and the wrong expectation as to how experimental quantities are related in the EFT. We illustrate the issues involved considering the $\\rm S$ parameter and the off shell triple gauge coupling (TGC) verticies. We show that the relationships between $h \\rightarrow V \\bar{f} \\, f$ decay and the off shell TGC verticies are subject to these subtleties, and how the connections between these observables vanish in the limit of strong bounds due to LEP. The challenge of using constructed observables...

  18. Emerging local warming signals in observational data

    E-Print Network [OSTI]

    Mahlstein, Irina

    The global average temperature of the Earth has increased, but year-to-year variability in local climates impedes the identification of clear changes in observations and human experience. For a signal to become obvious in ...

  19. Spectrum of Controlling and Observing Complex Networks

    E-Print Network [OSTI]

    Yan, Gang; Barzel, Baruch; Slotine, Jean-Jacques; Liu, Yang-Yu; Barabasi, Albert-Laszlo

    2015-01-01

    Observing and controlling complex networks are of paramount interest for understanding complex physical, biological and technological systems. Recent studies have made important advances in identifying sensor or driver nodes, through which we can observe or control a complex system. Yet, the observation uncertainty induced by measurement noise and the energy cost required for control continue to be significant challenges in practical applications. Here we show that the control energy cost and the observation uncertainty vary widely in different directions of the state space. In particular, we find that if all nodes are directly driven, control is energetically feasible, as the maximum energy cost increases sublinearly with the system size. If, however, we aim to control a system by driving only a single node, control in some directions is energetically prohibitive, increasing exponentially with the system size. For the cases in between, the maximum energy decays exponentially if we increase the number of driv...

  20. Observation of the 0-fs pulse

    E-Print Network [OSTI]

    Zare, Richard N.

    Observation of the 0-fs pulse By W.H. Knox, R.S. Knox,J.F.Hoose, and R.N. Zare T he quest for the world's shor test laser pulse has led to a re markable pace of develop ment in ultrafast laser technology. Al though pulses of only a few cycles duration have been made, clearly the observation of a 0-fs

  1. Gamma-Ray Line Observations with RHESSI

    E-Print Network [OSTI]

    David M. Smith

    2004-04-30

    The Reuven Ramaty High Energy Solar Spectroscopic Imager (RHESSI) has been observing gamma-ray lines from the Sun and the Galaxy since its launch in February 2002. Here I summarize the status of RHESSI observations of solar lines (nuclear de-excitation, neutron capture, and positron annihilation), the lines of $^{26}$Al and $^{60}$Fe from the inner Galaxy, and the search for positron annihilation in novae.

  2. Correlation between human observer performance and model observer performance in differential phase contrast CT

    SciTech Connect (OSTI)

    Li, Ke; Garrett, John; Chen, Guang-Hong

    2013-11-15

    Purpose: With the recently expanding interest and developments in x-ray differential phase contrast CT (DPC-CT), the evaluation of its task-specific detection performance and comparison with the corresponding absorption CT under a given radiation dose constraint become increasingly important. Mathematical model observers are often used to quantify the performance of imaging systems, but their correlations with actual human observers need to be confirmed for each new imaging method. This work is an investigation of the effects of stochastic DPC-CT noise on the correlation of detection performance between model and human observers with signal-known-exactly (SKE) detection tasks.Methods: The detectabilities of different objects (five disks with different diameters and two breast lesion masses) embedded in an experimental DPC-CT noise background were assessed using both model and human observers. The detectability of the disk and lesion signals was then measured using five types of model observers including the prewhitening ideal observer, the nonprewhitening (NPW) observer, the nonprewhitening observer with eye filter and internal noise (NPWEi), the prewhitening observer with eye filter and internal noise (PWEi), and the channelized Hotelling observer (CHO). The same objects were also evaluated by four human observers using the two-alternative forced choice method. The results from the model observer experiment were quantitatively compared to the human observer results to assess the correlation between the two techniques.Results: The contrast-to-detail (CD) curve generated by the human observers for the disk-detection experiments shows that the required contrast to detect a disk is inversely proportional to the square root of the disk size. Based on the CD curves, the ideal and NPW observers tend to systematically overestimate the performance of the human observers. The NPWEi and PWEi observers did not predict human performance well either, as the slopes of their CD curves tended to be steeper. The CHO generated the best quantitative agreement with human observers with its CD curve overlapping with that of human observer. Statistical equivalence between CHO and humans can be claimed within 11% of the human observer results, including both the disk and lesion detection experiments.Conclusions: The model observer method can be used to accurately represent human observer performance with the stochastic DPC-CT noise for SKE tasks with sizes ranging from 8 to 128 pixels. The incorporation of the anatomical noise remains to be studied.

  3. Selecting Observation Platforms for Optimized Anomaly Detectability under Unreliable Partial Observations

    SciTech Connect (OSTI)

    Wen-Chiao Lin; Humberto E. Garcia; Tae-Sic Yoo

    2011-06-01

    Diagnosers for keeping track on the occurrences of special events in the framework of unreliable partially observed discrete-event dynamical systems were developed in previous work. This paper considers observation platforms consisting of sensors that provide partial and unreliable observations and of diagnosers that analyze them. Diagnosers in observation platforms typically perform better as sensors providing the observations become more costly or increase in number. This paper proposes a methodology for finding an observation platform that achieves an optimal balance between cost and performance, while satisfying given observability requirements and constraints. Since this problem is generally computational hard in the framework considered, an observation platform optimization algorithm is utilized that uses two greedy heuristics, one myopic and another based on projected performances. These heuristics are sequentially executed in order to find best observation platforms. The developed algorithm is then applied to an observation platform optimization problem for a multi-unit-operation system. Results show that improved observation platforms can be found that may significantly reduce the observation platform cost but still yield acceptable performance for correctly inferring the occurrences of special events.

  4. The web-PLOP observation prioritisation system

    E-Print Network [OSTI]

    Colin Snodgrass; Yiannis Tsapras; Rachel Street; Daniel Bramich; Keith Horne; Martin Dominik; Alasdair Allan

    2008-05-14

    We present a description of the automated system used by RoboNet to prioritise follow up observations of microlensing events to search for planets. The system keeps an up-to-date record of all public data from OGLE and MOA together with any existing RoboNet data and produces new PSPL fits whenever new data arrives. It then uses these fits to predict the current or future magnitudes of events, and selects those to observe which will maximise the probability of detecting planets for a given telescope and observing time. The system drives the RoboNet telescopes automatically based on these priorities, but it is also designed to be used interactively by human observers. The prioritisation options, such as telescope/instrument parameters, observing conditions and available time can all be controlled via a web-form, and the output target list can also be customised and sorted to show the parameters that the user desires. The interactive interface is available at http://www.artemis-uk.org/web-PLOP/

  5. Numerical Model Construction with Closed Observables

    E-Print Network [OSTI]

    Felix Dietrich; Gerta Köster; Hans-Joachim Bungartz

    2015-10-18

    Performing analysis, optimization and control using simulations of many-particle systems is computationally demanding when no macroscopic model for the dynamics of the variables of interest is available. In case observations on the macroscopic scale can only be produced via legacy simulator code or live experiments, finding a model for these macroscopic variables is challenging. In this paper, we employ time-lagged embedding theory to construct macroscopic numerical models from output data of a black box, such as a simulator or live experiments. Since the state space variables of the constructed, coarse model are dynamically closed and observable by an observation function, we call these variables closed observables. The approach is an online-offline procedure, as model construction from observation data is performed offline and the new model can then be used in an online phase, independent of the original. We illustrate the theoretical findings with numerical models constructed from time series of a two-dimensional ordinary differential equation system, and from the density evolution of a transport-diffusion system. Applicability is demonstrated in a real-world example, where passengers leave a train and the macroscopic model for the density flow onto the platform is constructed with our approach. If only the macroscopic variables are of interest, simulation runtimes with the numerical model are three orders of magnitude lower compared to simulations with the original fine scale model. We conclude with a brief discussion of possibilities of numerical model construction in systematic upscaling, network optimization and uncertainty quantification.

  6. OBSERVING CORONAL NANOFLARES IN ACTIVE REGION MOSS

    SciTech Connect (OSTI)

    Testa, Paola; DeLuca, Ed; Golub, Leon; Korreck, Kelly; Weber, Mark; De Pontieu, Bart; Martinez-Sykora, Juan; Title, Alan; Hansteen, Viggo; Cirtain, Jonathan; Winebarger, Amy; Kobayashi, Ken; Kuzin, Sergey; Walsh, Robert; DeForest, Craig

    2013-06-10

    The High-resolution Coronal Imager (Hi-C) has provided Fe XII 193A images of the upper transition region moss at an unprecedented spatial ({approx}0.''3-0.''4) and temporal (5.5 s) resolution. The Hi-C observations show in some moss regions variability on timescales down to {approx}15 s, significantly shorter than the minute-scale variability typically found in previous observations of moss, therefore challenging the conclusion of moss being heated in a mostly steady manner. These rapid variability moss regions are located at the footpoints of bright hot coronal loops observed by the Solar Dynamics Observatory/Atmospheric Imaging Assembly in the 94 A channel, and by the Hinode/X-Ray Telescope. The configuration of these loops is highly dynamic, and suggestive of slipping reconnection. We interpret these events as signatures of heating events associated with reconnection occurring in the overlying hot coronal loops, i.e., coronal nanoflares. We estimate the order of magnitude of the energy in these events to be of at least a few 10{sup 23} erg, also supporting the nanoflare scenario. These Hi-C observations suggest that future observations at comparable high spatial and temporal resolution, with more extensive temperature coverage, are required to determine the exact characteristics of the heating mechanism(s).

  7. Observations of Radio Giant Pulses with GAVRT

    E-Print Network [OSTI]

    Jones, Glenn

    2015-01-01

    Radio giant pulses provide a unique opportunity to study the pulsar radio emission mechanism in exquisite detail. Previous studies have revealed a wide range of properties and phenomena, including extraordinarily high brightness temperatures, sub-nanosecond emission features, and banded dynamic spectra. New measurements of giant pulse characteristics can help guide and test theoretical emission models. To this end, an extensive observation campaign has begun which will provide more than 500 hours on the Crab with a 34-meter antenna located in California, USA. The observations are being done as part of an educational outreach program called the Goldstone-Apple Valley Radio Telescope (GAVRT). This antenna has a novel wide bandwidth receiver which provides up to 8 GHz of instantaneous bandwidth in the range of 2.5 to 14 GHz. These observations will provide detailed information about the variability, amplitude distribution, and detailed frequency structure of radio giant pulses. In addition, a database of pulses ...

  8. Black Holes: from Speculations to Observations

    E-Print Network [OSTI]

    Thomas W. Baumgarte

    2006-04-13

    This paper provides a brief review of the history of our understanding and knowledge of black holes. Starting with early speculations on ``dark stars'' I discuss the Schwarzschild "black hole" solution to Einstein's field equations and the development of its interpretation from "physically meaningless" to describing the perhaps most exotic and yet "most perfect" macroscopic object in the universe. I describe different astrophysical black hole populations and discuss some of their observational evidence. Finally I close by speculating about future observations of black holes with the new generation of gravitational wave detectors.

  9. VLA multifrequency observations of RS CVn binaries

    E-Print Network [OSTI]

    J. Garcia-Sanchez; J. M. Paredes; M. Ribo

    2003-03-21

    We present multiepoch Very Large Array (VLA) observations at 1.4 GHz, 4.9 GHz, 8.5 GHz and 14.9 GHz for a sample of eight RS CVn binary systems. Circular polarization measurements of these systems are also reported. Most of the fluxes observed are consistent with incoherent emission from mildly relativistic electrons. Several systems show an increase of the degree of circular polarization with increasing frequency in the optically thin regime, in conflict with predictions by gyrosynchrotron models. We observed a reversal in the sense of circular polarization with increasing frequency in three non-eclipsing systems: EI Eri, DM Uma and HD 8358. We find clear evidence for coherent plasma emission at 1.4 GHz in the quiescent spectrum of HD 8358 during the helicity reversal. The degrees of polarization of the other two systems could also be accounted for by a coherent emission process. The observations of ER Vul revealed two U-shaped flux spectra at the highest frequencies. The U-shape of the spectra may be accounted for by an optically thin gyrosynchrotron source for the low frequency part whereas the high frequency part is dominated by a thermal emission component.

  10. Equivalences on Observable Processes Irek Ulidowski

    E-Print Network [OSTI]

    Ulidowski, Irek

    and finitely observable. We define copy+refusal testing equivalence as indistinguishabil- ity by copy, provided their operational meaning is defined by realistically implementable transition rules. Process behaviour which can be established by so-called local testing but not global testing is called locally

  11. Experimental Observation of Bonding Electrons in Proteins*

    E-Print Network [OSTI]

    Experimental Observation of Bonding Electrons in Proteins* (Received for publication, April 15 enables bonding details of electron distributions in proteins to be revealed experimentally for the first time. We move one step closer to imaging directly the fine details of the electronic structure on which

  12. Energy flow observables in hadronic collisions

    E-Print Network [OSTI]

    F. Hautmann

    2012-05-24

    We present recent QCD calculations of energy flow distributions associated with the production of jets at wide rapidity separations in high-energy hadron collisions, and discuss the role of these observables to analyze contributions from parton showering and from multiple parton collisions.

  13. OH Maser Observations of Planetary Nebulae Precursors

    E-Print Network [OSTI]

    R. M. Deacon; J. M. Chapman; A. J. Green

    2004-06-08

    We present OH maser observations at 1612, 1665, 1667, and 1720 MHz for 86 post-asymptotic giant branch (post-AGB) stars selected from a survey of 1612 MHz maser sources in the Galactic Plane. The observations were taken with the Parkes Telescope and the Australia Telescope Compact Array between 2002 September and 2003 August. Post-AGB stars are the precursors to planetary nebulae, the diverse morphological range of which is unexplained. The maser observations were taken to investigate the onset and incidence of wind asymmetries during the post-AGB phase. We re-detected all 86 sources at 1612 MHz while 27 sources were detected at 1665 and 45 at 1667 MHz. One source was re-detected at 1720 MHz. We present a classification scheme for the maser profiles and show that 25% of sources in our sample are likely to have asymmetric or bipolar outflows. From a comparison of the maser and far-infrared properties we find that there is a likely trend in the shape of the maser profiles with some sources evolving from double-peaked to irregular to fully bipolar profiles. A subset of higher-mass sources stand out as having almost no mainline emission and mostly double-peaked profiles. At least 25% of sources in the sample are variable at one or more of the frequencies observed. We also confirm a previously-noted 1667 MHz overshoot phenomenon.

  14. GEO Secretariat Global Earth Observing System of

    E-Print Network [OSTI]

    and Epidemiology 3. Energy Management 4. Climate Variability & Change 5. Water Management 6. Weather Forecasting 7© GEO Secretariat Global Earth Observing System of Systems (GEOSS): Biodiversity, Ecosystems and GEO BON GEO Forest Monitoring Symposium 4 November 2008 Douglas M. Muchoney, Ph.D. U.S. Geological

  15. General relativistic observables of the GRAIL mission

    E-Print Network [OSTI]

    Turyshev, Slava G; Sazhin, Mikhail V

    2012-01-01

    We present a realization of astronomical relativistic reference frames in the solar system and its application to the GRAIL mission. We model the necessary spacetime coordinate transformations for light-trip time computations and address some practical aspects of the implementation of the resulting model. We develop all the relevant relativistic coordinate transformations that are needed to describe the motion of the GRAIL spacecraft and to compute all observable quantities. We take into account major relativistic effects contributing to the dual one-way range observable, which is derived from one-way signal travel times between the two GRAIL spacecraft. We develop a general relativistic model for this fundamental observable of GRAIL, accurate to 1 $\\mu$m. We develop and present a relativistic model for another key observable of this experiment, the dual one-way range-rate, accurate to 1 $\\mu$m/s. The presented formulation justifies the basic assumptions behind the design of the GRAIL mission. It may also be ...

  16. General relativistic observables of the GRAIL mission

    E-Print Network [OSTI]

    Slava G. Turyshev; Viktor T. Toth; Mikhail V. Sazhin

    2012-12-18

    We present a realization of astronomical relativistic reference frames in the solar system and its application to the GRAIL mission. We model the necessary spacetime coordinate transformations for light-trip time computations and address some practical aspects of the implementation of the resulting model. We develop all the relevant relativistic coordinate transformations that are needed to describe the motion of the GRAIL spacecraft and to compute all observable quantities. We take into account major relativistic effects contributing to the dual one-way range observable, which is derived from one-way signal travel times between the two GRAIL spacecraft. We develop a general relativistic model for this fundamental observable of GRAIL, accurate to 1 $\\mu$m. We develop and present a relativistic model for another key observable of this experiment, the dual one-way range-rate, accurate to 1 $\\mu$m/s. The presented formulation justifies the basic assumptions behind the design of the GRAIL mission. It may also be used to further improve the already impressive results of this lunar gravity recovery experiment after the mission is complete. Finally, we present transformation rules for frequencies and gravitational potentials and their application to GRAIL.

  17. 8) Stratospheric equatorial variability a) Observations

    E-Print Network [OSTI]

    Lott, Francois

    speed. Phase lines inclined eastward when altitude increases indicating upward propation Signal field) Westward phase propagation but eastward group propagation Phase lines inclined westward Signal;5 Satellites wind observations (UARS, Swinbak et Ortland 1997) The Quasi-Biennial Oscillation (low stratosphere

  18. Uncertain Probabilistic Roadmaps with Observations Richard Dearden

    E-Print Network [OSTI]

    Yao, Xin

    Uncertain Probabilistic Roadmaps with Observations Richard Dearden School of Computer Science Science University of Birmingham Birmingham, B15 2TT, UK mlk@cs.bham.ac.uk Abstract Probabilistic roadmaps. Introduction Probabilistic Roadmaps (PRM) are a popular technique for path planning in high dimensional spaces

  19. Observation of D(0) ? K+pi-

    E-Print Network [OSTI]

    Ammar, Raymond G.; Ball, S.; Baringer, Philip S.; Bean, Alice; Besson, David Zeke; Coppage, Don; Copty, N.; Davis, Robin E. P.; Hancock, N.; Kelly, M.; Kwak, Nowhan; Lam, H.

    1994-03-01

    Using the CLEO II data sample, with an integrated luminosity of 1.8 fb-1 at and near the UPSILON(4S) resonance, we have observed a signal for D0 --> K+pi-, which could be due to either D0D0BAR mixing or doubly Cabibbo suppressed decay, or a...

  20. Timed Automata with Observers under Energy Constraints

    E-Print Network [OSTI]

    Doyen, Laurent

    of schedules given an initial energy level of one. For one-clock priced timed automata both the lowerTimed Automata with Observers under Energy Constraints Patricia Bouyer Lab. Spécification et@lsv.ens-cachan.fr ABSTRACT In this paper we study one-clock priced timed automata in which prices can grow linearly ( p = k

  1. On the consistent use of Constructed Observables

    E-Print Network [OSTI]

    Michael Trott

    2015-01-17

    We define "constructed observables" as relating experimental measurements to terms in a Lagrangian while simultaneously making assumptions about possible deviations from the Standard Model (SM), in other Lagrangian terms. Ensuring that the SM effective field theory (EFT) is constrained correctly when using constructed observables requires that their defining conditions are imposed on the EFT in a manner that is consistent with the equations of motion. Failing to do so can result in a "functionally redundant" operator basis and the wrong expectation as to how experimental quantities are related in the EFT. We illustrate the issues involved considering the $\\rm S$ parameter and the off shell triple gauge coupling (TGC) verticies. We show that the relationships between $h \\rightarrow V \\bar{f} \\, f$ decay and the off shell TGC verticies are subject to these subtleties, and how the connections between these observables vanish in the limit of strong bounds due to LEP. The challenge of using constructed observables to consistently constrain the Standard Model EFT is only expected to grow with future LHC data, as more complex processes are studied.

  2. Observability of Neuronal Network Motifs (Invited Paper)

    E-Print Network [OSTI]

    Brennan, Sean

    Observability of Neuronal Network Motifs (Invited Paper) Andrew J. Whalen*t, Sean N. Brennan Engineering, + Engineering Science and Mechanics, Neurosurgery, and Physics, Penn State University, University) neuronal networks as a function of 1) the connection topology and sym metry, 2) the measured nodes, and 3

  3. Observational constraints on Tachyon and DBI inflation

    SciTech Connect (OSTI)

    Li, Sheng; Liddle, Andrew R., E-mail: sl277@sussex.ac.uk, E-mail: arl@roe.ac.uk [Astronomy Centre, University of Sussex, Brighton, BN1 9QH (United Kingdom)

    2014-03-01

    We present a systematic method for evaluation of perturbation observables in non-canonical single-field inflation models within the slow-roll approximation, which allied with field redefinitions enables predictions to be established for a wide range of models. We use this to investigate various non-canonical inflation models, including Tachyon inflation and DBI inflation. The Lambert W function will be used extensively in our method for the evaluation of observables. In the Tachyon case, in the slow-roll approximation the model can be approximated by a canonical field with a redefined potential, which yields predictions in better agreement with observations than the canonical equivalents. For DBI inflation models we consider contributions from both the scalar potential and the warp geometry. In the case of a quartic potential, we find a formula for the observables under both non-relativistic (sound speed c{sub s}{sup 2} ? 1) and relativistic behaviour (c{sub s}{sup 2} || 1) of the scalar DBI inflaton. For a quadratic potential we find two branches in the non-relativistic c{sub s}{sup 2} ? 1 case, determined by the competition of model parameters, while for the relativistic case c{sub s}{sup 2} ? 0, we find consistency with results already in the literature. We present a comparison to the latest Planck satellite observations. Most of the non-canonical models we investigate, including the Tachyon, are better fits to data than canonical models with the same potential, but we find that DBI models in the slow-roll regime have difficulty in matching the data.

  4. Observations of Solids in Protoplanetary Disks

    E-Print Network [OSTI]

    Andrews, Sean M

    2015-01-01

    This review addresses the state of research that employs astronomical (remote sensing) observations of solids ("dust") in young circumstellar disks to learn about planet formation. The intention is for it to serve as an accessible, introductory, pedagogical resource for junior scientists interested in the subject. After some historical background and a basic observational primer, the focus is shifted to the three fundamental topics that broadly define the field: (1) demographics -- the relationships between disk properties and the characteristics of their environments and hosts; (2) structure -- the spatial distribution of disk material and its associated physical conditions and composition; and (3) evolution -- the signposts of key changes in disk properties, including the growth and migration of solids and the impact of dynamical interactions with young planetary systems. Based on the state of the art results in these areas, suggestions are made for potentially fruitful lines of work in the near future.

  5. Observables in Strongly Coupled Anisotropic Theories

    E-Print Network [OSTI]

    Dimitrios Giataganas

    2013-12-30

    We review certain anisotropic gauge/gravity dualities, focusing more on a theory with space dependent axion term. Then we discuss and also present some new results for several observables: the static potential and force, the imaginary part of the static potential, the quark dipole in the plasma wind, the drag force and diffusion time, the jet quenching of heavy and light quarks, the energy loss of rotating quarks, the photon production and finally the violation of the holographic viscosity over entropy bound. The corresponding weakly coupled results are also discussed. Finally we investigate the bounds of the parameters of the current strongly coupled anisotropic theories attempting to match them with the observed quark-gluon plasma and report the problems appear.

  6. Fermi Observations of Gamma-ray Bursts

    SciTech Connect (OSTI)

    Ohno, Masanori [Institute of Space and Astronautical Science, JAXA, 3-1-1 Yoshinodai, Chuo-ku, Sagamihara, Kanagawa 252-5210 (Japan)

    2010-10-15

    The gamma-ray emission mechanism of Gamma-ray bursts (GRBs) are still unknown. Fermi Gamma-ray Space Telescope successfully detected high-energy (> 100 MeV) emission from 17 GRBs since its launch. Fermi revealed the distinct temporal behaviors and extra spectral component from high-energy emission. These new observational results are driving many theoretical implications, such as leptonic, hadronic and afterglow origin. The highest energy photon detected by Fermi gives a constraint on the bulk Lorentz factor of the ultra-relativistic jets of GRBs. The impact of the Fermi GRB observations extends not only to the GRB-related issues but also to the outside GRB physics, such as quantum gravity and model of the extra galactic background light.

  7. First direct observation of muon antineutrino disappearance

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

    Adamson, P.

    2011-07-05

    This letter reports the first direct observation of muon antineutrino disappearance. The MINOS experiment has taken data with an accelerator beam optimized for ??? production, accumulating an exposure of 1.71 x 1020 protons on target. In the Far Detector, 97 charged current ??? events are observed. The no-oscillation hypothesis predicts 156 events and is excluded at 6.3?. The best fit to oscillation yields |?m?2| = (3.36-0.40 +0.46(stat.) ± 0.06(syst.)) x 10-3 eV2, sin2(2 ??) = 0.86-0.12+0.11 (stat.) ± 0.01(syst.). The MINOS ?? and ??? measurements are consistent at the 2.0% confidence level, assuming identical underlying oscillation parameters.

  8. Observational constraints on braneworld chaotic inflation

    E-Print Network [OSTI]

    Andrew R Liddle; Anthony J Smith

    2003-08-13

    We examine observational constraints on chaotic inflation models in the Randall-Sundrum Type II braneworld. If inflation takes place in the high-energy regime, the perturbations produced by the quadratic potential are further from scale-invariance than in the standard cosmology, in the quartic case more or less unchanged, while for potentials of greater exponent the trend is reversed. We test these predictions against a data compilation including the WMAP measurements of microwave anisotropies and the 2dF galaxy power spectrum. While in the standard cosmology the quartic potential is at the border of what the data allow and all higher powers excluded, we find that in the high-energy regime of braneworld inflation even the quadratic case is under strong observational pressure. We also investigate the intermediate regime where the brane tension is comparable to the inflationary energy scale, where the deviations from scale-invariance prove to be greater.

  9. APS DPP, Savannah 2004 Tomographic Observation ofTomographic Observation of

    E-Print Network [OSTI]

    Washington at Seattle, University of

    -formed FRC, or generate a FRC from a pre-ionized plasma The TCS chamber is constructed of a 40-cm radiusAPS DPP, Savannah 2004 Tomographic Observation ofTomographic Observation of FRC Rotational Modes and Stabilization byFRC Rotational Modes and Stabilization by Various RMF Antenna Geometries in TCSVarious RMF

  10. LNG Observer: Second Qatargas train goes onstream

    SciTech Connect (OSTI)

    1997-01-01

    The January-February, 1997 issue of the LNG Observer is presented. The following topics are discussed: second Qatargas train goes onstream; financing for the eighth Indonesian liquefaction train; Koreans take stakes in Oman LNG; US imports and exports of LNG in 1996; A 60% increase in proved reserves on the North West Shelf; proposals for Indian LNG terminal CEDIGAZ forecasts world LNG trade by 2010; growth for North African gas production and exports; and new forecast sees strong growth for Asian gas.

  11. Observational Approach to Chromium Site Remediation - 13266

    SciTech Connect (OSTI)

    Scott Myers, R.

    2013-07-01

    Production reactors at the U.S. Department of Energy's (DOE) Hanford Site in Richland, Washington, required massive quantities of water for reactor cooling and material processing. To reduce corrosion and the build-up of scale in pipelines and cooling systems, sodium dichromate was added to the water feedstock. Spills and other releases at the makeup facilities, as well as leaks from miles of pipelines, have led to numerous areas with chromium-contaminated soil and groundwater, threatening fish populations in the nearby Columbia River. Pump-and-treat systems have been installed to remove chromium from the groundwater, but significant contamination remain in the soil column and poses a continuing threat to groundwater and the Columbia River. Washington Closure Hanford, DOE, and regulators are working on a team approach that implements the observational approach, a strategy for effectively dealing with the uncertainties inherent in subsurface conditions. Remediation of large, complex waste sites at a federal facility is a daunting effort. It is particularly difficult to perform the work in an environment of rapid response to changing field and contamination conditions. The observational approach, developed by geotechnical engineers to accommodate the inherent uncertainties in subsurface conditions, is a powerful and appropriate method for site remediation. It offers a structured means of quickly moving into full remediation and responding to the variations and changing conditions inherent in waste site cleanups. A number of significant factors, however, complicate the application of the observational approach for chromium site remediation. Conceptual models of contamination and site conditions are difficult to establish and get consensus on. Mid-stream revisions to the design of large excavations are time-consuming and costly. And regulatory constraints and contract performance incentives can be impediments to the flexible responses required under the observational approach. The WCH project team is working closely with stakeholders and taking a number of steps to meet these challenges in a continuing effort to remediate chromium contaminated soil in an efficient and cost-effective manner. (authors)

  12. Self-potential observations during hydraulic fracturing

    SciTech Connect (OSTI)

    Moore, Jeffrey R.; Glaser, Steven D.

    2007-09-13

    The self-potential (SP) response during hydraulic fracturing of intact Sierra granite was investigated in the laboratory. Excellent correlation of pressure drop and SP suggests that the SP response is created primarily by electrokinetic coupling. For low pressures, the variation of SP with pressure drop is linear, indicating a constant coupling coefficient (Cc) of -200 mV/MPa. However for pressure drops >2 MPa, the magnitude of the Cc increases by 80% in an exponential trend. This increasing Cc is related to increasing permeability at high pore pressures caused by dilatancy of micro-cracks, and is explained by a decrease in the hydraulic tortuosity. Resistivity measurements reveal a decrease of 2% prior to hydraulic fracturing and a decrease of {approx}35% after fracturing. An asymmetric spatial SP response created by injectate diffusion into dilatant zones is observed prior to hydraulic fracturing, and in most cases this SP variation revealed the impending crack geometry seconds before failure. At rupture, injectate rushes into the new fracture area where the zeta potential is different than in the rock porosity, and an anomalous SP spike is observed. After fracturing, the spatial SP distribution reveals the direction of fracture propagation. Finally, during tensile cracking in a point load device with no water flow, a SP spike is observed that is caused by contact electrification. However, the time constant of this event is much less than that for transients observed during hydraulic fracturing, suggesting that SP created solely from material fracture does not contribute to the SP response during hydraulic fracturing.

  13. Cosmological inference using gravitational wave observations alone

    E-Print Network [OSTI]

    Walter Del Pozzo; Tjonnie G. F. Li; Chris Messenger

    2015-06-22

    Gravitational waves emitted during the coalescence of binary neutron star systems are self-calibrating signals. As such they can provide a direct measurement of the luminosity distance to a source without the need for a cosmic distance scale ladder. In general, however, the corresponding redshift measurement needs to be obtained electromagnetically since it is totally degenerate with the total mass of the system. Nevertheless, recent Fisher matrix studies has shown that if information about the equation of state of the neutron stars is available, it is indeed possible to extract redshift information from the gravitational wave signal alone. Therefore, measuring the cosmological parameters in pure gravitational wave fashion is possible. Furthermore, the huge number of sources potentially observable by the Einstein Telescope has led to speculations that the gravitational wave measurement is potentially competitive with traditional methods. The Einstein telescope is a conceptual study for a third generation gravitational wave detector which is designed to yield detections of $10^3-10^7$ binary neutron star systems per year. This study presents the first Bayesian investigation of the accuracy with which the cosmological parameters can be measured using observations of binary neutron star systems by the Einstein Telescope with the one year of observations. We find by direct simulation of $10^3$ detections of binary neutron stars that, within our simplifying assumptions, $H_0,\\Omega_m,\\Omega_\\Lambda,w_0$ and $w_1$ can be measured at the $95\\%$ level with an accuracy of $\\sim 8\\%,65\\%,39\\%,80\\%$ and $90\\%$, respectively. We also find, by extrapolation, that a measurement accuracy comparable with current measurements by Planck is reached for a number of observed events $O(10^{6-7})$

  14. X-ray Observations of Mrk 231

    E-Print Network [OSTI]

    T. J. Turner

    1998-08-10

    This paper presents new X-ray observations of Mrk 231, an active galaxy of particular interest due to its large infrared luminosity and the presence of several blueshifted broad absorption line (BAL) systems, a phenomenon observed in a small fraction of QSOs. A ROSAT HRI image of Mrk 231 is presented, this shows an extended region of soft X-ray emission, covering several tens of kpc, consistent with the extent of the host galaxy. An ASCA observation of Mrk 231 is also presented. Hard X-rays are detected but the data show no significant variability in X-ray flux. The hard X-ray continuum is heavily attenuated and X-ray column estimates range from ~ 2 x 10^{22} - 10^{23} cm^{-2} depending on whether the material is assumed to be neutral or ionized, and on the model assumed for the extended X-ray component. These ASCA data provide only the second hard X-ray spectrum of a BAL AGN presented to date. The broad-band spectral-energy-distribution of the source is discussed. While Mrk 231 is X-ray weak compared to Seyfert 1 galaxies, it has an optical-to-X-ray spectrum typical of a QSO.

  15. Chaos, Dirac observables and constraint quantization

    E-Print Network [OSTI]

    Bianca Dittrich; Philipp A. Hoehn; Tim A. Koslowski; Mike I. Nelson

    2015-08-08

    There is good evidence that full general relativity is non-integrable or even chaotic. We point out the severe repercussions: differentiable Dirac observables and a reduced phase space do not exist in non-integrable constrained systems and are thus unlikely to occur in a generic general relativistic context. Instead, gauge invariant quantities generally become discontinuous, thus not admitting Poisson-algebraic structures and posing serious challenges to a quantization. Non-integrability also renders the paradigm of relational dynamics cumbersome, thereby straining common interpretations of the dynamics. We illustrate these conceptual and technical challenges with simple toy models. In particular, we exhibit reparametrization invariant models which fail to be integrable and, as a consequence, can either not be quantized with standard methods or lead to sick quantum theories without a semiclassical limit. These troubles are qualitatively distinct from semiclassical subtleties in unconstrained quantum chaos and can be directly traced back to the scarcity of Dirac observables. As a possible resolution, we propose to change the method of quantization by refining the configuration space topology until the generalized observables become continuous in the new topology and can acquire a quantum representation. This leads to the polymer quantization method underlying loop quantum cosmology and gravity. Remarkably, the polymer quantum theory circumvents the problems of the quantization with smooth topology, indicating that non-integrability and chaos, while a challenge, may not be a fundamental obstruction for quantum gravity.

  16. Rayleigh lidar observations of mesosphere temperature structure

    SciTech Connect (OSTI)

    Meriwether, J.W.; Dao, P.D.; Mcnutt, R.T.; Klemetti, W.; Moskowitz, W.; Davidson, G. [Hanscom Air Force Base, MA (United States)]|[PhotoMetrics, Inc., Woburn, MA (United States)

    1994-08-01

    Ground-based observations of atmospheric density profiles to 92 km were obtained for four successive seasons between summer 1989 and spring 1990. These results were obtained with a powerful Rayleigh lidar facility located at Wright Patterson Air Force Base (Dayton, Ohio). This instrument combined a 14-W XeF laser transmitter with a 2.54-m receiver mirror to observe returns from altitudes between 40 and 95 km. Analysis of the scale height dependence of the density profiles produced temperatures with a measurement error of about 5 K (approximately 2.5%) at 90 km when the lidar data was averaged for 20 min. and smoothed in height over 2.7 km. Examination of these profiles for the total of 18 nights showed that there often existed in the mesophere a layer of enhanced temperatures when compared with the U.S. standard profile. The layer centroid height was about 85 km for summer and 70 to 75 km for winter. Data obtained for the equinoctial periods showed the amplitude of these layers to be weak. The winter temperature profiles showed evidence for long-period waves passing through the region of the thermal anomaly while the equinox profiles revealed more sporadic wave activity with shorter vertical wavelengths. Both the winter and summer temperature data displayed regions where the observed lapse rate approached the adiabatic lapse rate. In the summer the wave activity near the iversion layer was weak.

  17. Infrared Freezing of Euclidean QCD observables

    E-Print Network [OSTI]

    Paul M. Brooks; C. J. Maxwell

    2006-08-22

    We consider the leading one-chain term in a skeleton expansion for QCD observables and show that for energies Q^2>\\Lambda^2, where Q^2=\\Lambda^2 is the Landau pole in the coupling, the skeleton expansion result is equivalent to the standard Borel integral representation, with ambiguities related to infrared (IR) renormalons. For Q^2freezing behaviour, vanishing at Q^2=0. Finiteness at Q^2=\\Lambda^2 implies specific relations between the residues of IR and UV renormalons in the Borel plane. These relations, only one of which has previously been noted (though it remained unexplained) are shown to follow from the continuity of the characteristic function in the skeleton expansion. By considering the compensation of non-perturbative and perturbative ambiguities we are led to a result for the Q^2 dependence of these observables at all Q^2, in which there is a single undetermined non-perturbative parameter, and which involves the skeleton expansion characteristic function. The observables freeze to zero in the infrared. We briefly consider the freezing behaviour of the Minkowskian R_{e+e-} ratio.

  18. Observational consequencies of baryonic gaseous dark matter

    E-Print Network [OSTI]

    Shchekinov, Yu A

    1998-01-01

    Possible observational consequencies of dark matter in the Galaxy in the form of dense molecular gas clouds -- clumpuscules of masses $M_c\\sim 10^{-3}~\\msun$ and radii $R_c\\sim 3\\times 10^{13}$ cm -- are considered. Recent models of the extreme scattering events -- refraction of radio-waves from quasars in dense plasma clumps in the Galactic halo -- definitely show on such clouds as possible dark matter candidate. We arugue that collisions of such clumpuscules are quite frequent: around $1-10~\\msun$ a year can be ejected in the intestellar medium due to collisions. Optical continuum and 21 cm emissions from post-collisional gas are found to be observable. We show that clumpuscules can form around O stars HII regions of sizes $R\\sim 30$ pc and emission measure $EM\\simeq 20$ cm$^{-6}$ pc, and can also be observable in $H_\\alpha$ emission. Evaporation of clumpuscules by external ionising radiation can be a substantial mass source. From requirement that the total mass input on the Hubble time cannot exceed the lu...

  19. Observational consequences of baryonic gaseous dark matter

    E-Print Network [OSTI]

    Yu. A. Shchekinov

    1998-12-03

    Possible observational consequences of dark matter in the Galaxy in the form of dense molecular gas clouds - clumpuscules of masses $M_c\\sim 10^{-3} \\msun$ and radii $R_c\\sim 3\\times 10^{13}$ cm - are considered. Recent models of the extreme scattering events - refraction of radio-waves from quasars in dense plasma clumps in the Galactic halo - definitely show on such clouds as possible dark matter candidate. We argue that collisions of such clumpuscules are quite frequent: around $1-10 \\msun$ a year can be ejected in the interstellar medium due to collisions. Optical continuum and 21 cm emissions from post-collisional gas are found to be observable. We show that clumpuscules can form around O stars HII regions of sizes $R\\sim 30$ pc and emission measure $EM\\simeq 20 cm^{-6}$ pc, and can also be observable in $H_\\alpha$ emission. Evaporation of clumpuscules by external ionizing radiation can be a substantial mass source. From requirement that the total mass input on the Hubble time cannot exceed the luminous mass in the Galaxy, typical radius of clouds is constrained as $R_c energy of the gas ejected by such clouds can be an efficient energy source for the Galactic halo.

  20. Apparatus for observing a hostile environment

    DOE Patents [OSTI]

    Nance, Thomas A. (Aiken, SC); Boylston, Micah L. (Williston, SC); Robinson, Casandra W. (Trenton, SC); Sexton, William C. (Aiken, SC); Heckendorn, Frank M. (Aiken, SC)

    2000-01-01

    An apparatus is provided for observing a hostile environment, comprising a housing and a camera capable of insertion within the housing. The housing is a double wall assembly with an inner and outer wall with an hermetically sealed chamber therebetween. A housing for an optical system used to observe a hostile environment is provided, comprising a transparent, double wall assembly. The double wall assembly has an inner wall and an outer wall with an hermetically sealed chamber therebetween. The double wall assembly has an opening and a void area in communication with the opening. The void area of the housing is adapted to accommodate the optical system within said void area. An apparatus for protecting an optical system used to observe a hostile environment is provided comprising a housing; a tube positioned within the housing; and a base for supporting the housing and the tube. The housing comprises a double wall assembly having an inner wall and an outerwall with an hermetically sealed chamber therebetween. The tube is adapted to house the optical system therein.

  1. MULTIWAVELENGTH OBSERVATIONS OF THE SS 433 JETS

    SciTech Connect (OSTI)

    Marshall, Herman L.; Canizares, Claude R.; Schulz, Norbert S.; Nowak, Michael [Kavli Institute for Astrophysics and Space Research, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139 (United States); Hillwig, Todd [Department of Physics and Astronomy, Valparaiso University, Valparaiso, IN 46383 (United States); Mioduszewski, Amy; Rupen, Michael [NRAO, P.O. Box 2, Socorro, NM 87801 (United States); Heinz, Sebastian, E-mail: hermanm@space.mit.edu, E-mail: crc@space.mit.edu, E-mail: nss@space.mit.edu, E-mail: mnowak@space.mit.edu, E-mail: todd.hillwig@valpo.edu, E-mail: amiodusz@nrao.edu, E-mail: mrupen@aoc.nrao.edu, E-mail: heinzs@astro.wisc.edu [Astronomy Department, 5408 Sterling Hall, University of Wisconsin, Madison, WI 53706 (United States)

    2013-09-20

    We present observations of the SS 433 jets using the Chandra High Energy Transmission Grating Spectrometer with contemporaneous optical and Very Long Baseline Array observations. The X-ray and optical emission line regions are found to be related but not coincident as the optical line emission persists for days while the X-ray emission lines fade in less than 5000 s. The line Doppler shifts from the optical and X-ray lines match well, indicating that they are less than 3 × 10{sup 14} cm apart. The jet Doppler shifts show aperiodic variations that could result from shocks in interactions with the local environment. These perturbations are consistent with a change in jet direction but not jet speed. The proper motions of the radio knots match the kinematic model only if the distance to SS 433 is 4.5 ± 0.2 kpc. Observations during eclipse show that the occulted emission is very hard, seen only above 2 keV and rising to comprise >50% of the flux at 8 keV. The soft X-ray emission lines from the jet are not blocked, constraining the jet length to ?> 2 × 10{sup 12} cm. The base jet density is in the range 10{sup 10-13} cm{sup –3}, in contrast to our previous estimate based on the Si XIII triplet, which is likely to have been affected by UV de-excitation. There is a clear overabundance of Ni by a factor of about 15 relative to the solar value, which may have resulted from an unusual supernova that formed the compact object.

  2. Direct Observation of Paramagnons in Palladium

    SciTech Connect (OSTI)

    Doubble, R.; Hayden, S M.; Dai, Pengcheng; Mook Jr, Herbert A; Thompson, James R; Frost, C.

    2010-01-01

    We report an inelastic neutron scattering study of the spin fluctuations in the nearly ferromagnetic element palladium. Dispersive over-damped collective magnetic excitations or 'paramagnons' are observed up to 128 meV. We analyze our results in terms of a Moriya-Lonzarich-type spin-fluctuation model and estimate the contribution of the spin fluctuations to the low-temperature heat capacity. In spite of the paramagnon excitations being relatively strong, their relaxation rates are large. This leads to a small contribution to the low-temperature electronic specific heat.

  3. VLBI polarimetric observations of 3C147

    E-Print Network [OSTI]

    A. Rossetti; F. Mantovani; D. Dallacasa

    2004-12-29

    We present multi-frequency VLBI observations of the Compact Steep-spectrum Quasar 3C147 (0538+498) made with the VLBA at the four frequencies in the available 5 GHz band and at 8.4 GHz (still under analysis), from which we derived millarcsecond-resolution images of the total intensity, polarization, and rotation measure distributions. The source shows a core-jet structure, with a compact feature and a jet, extending about 200 mas to the South-West. We detect polarized emission in two bright features in the inner jet; the rotation measure of this features (aprox -1630 rad m(-2), aprox -540 rad m(-2)).

  4. Gamma-Ray Burst observations with Fermi

    E-Print Network [OSTI]

    Bissaldi, Elisabetta; Omodei, Nicola; Vianello, Giacomo; von Kienlin, Andreas

    2015-01-01

    After seven years of science operation, the Fermi mission has brought great advances in the study of Gamma-ray Bursts (GRBs). Over 1600 GRBs have been detected by the Gamma-ray Burst Monitor, and more than 100 of these are also detected by the Large Area Telescope above 30 MeV. We will give an overview of these observations, presenting the common properties in the GRB temporal and spectral behavior at high energies. We will also highlight the unique characteristics of some individual bursts. The main physical implications of these results will be discussed, along with open questions regarding GRB modeling in their prompt and temporally-extended emission phases.

  5. William Herschel, the First Observational Cosmologist

    ScienceCinema (OSTI)

    Lemonick, Michael [Princeton University and Time Magazine, Princeton, New Jersey, United States

    2010-01-08

    In the late 1700s, a composer, orchestra director and soloist named William Herschel became fascinated with astronomy, and, having built his own reflecting telescope, went out in his garden in Bath, England, one night and discovered Uranus?the first planet in human history ever found by an individual. The feat earned him a lifetime pension from King George III. But Herschel considered the discovery to be relatively unimportant in comparison to his real work: understanding the composition, structure and evolution of the universe. In pursuing that work, he became the first observational cosmologist.

  6. Superconductivity observed in platinum-silicon interface

    SciTech Connect (OSTI)

    Kuo, Pai-Chia, E-mail: paichia@phys.sinica.edu.tw [Research Program on Nanoscience and Nanotechnology, Academia Sinica, Taipei 11529, Taiwan (China); Institute of Physics, Academia Sinica, Taipei 11529, Taiwan (China); Department of Materials Science and Engineering, National Taiwan University, Taipei 10617, Taiwan (China); Chen, Chun-Wei [Department of Materials Science and Engineering, National Taiwan University, Taipei 10617, Taiwan (China); Lee, Ku-Pin; Shiue, Jessie, E-mail: yshiue@phys.sinica.edu.tw [Research Program on Nanoscience and Nanotechnology, Academia Sinica, Taipei 11529, Taiwan (China); Institute of Physics, Academia Sinica, Taipei 11529, Taiwan (China)

    2014-05-26

    We report the discovery of superconductivity with an onset temperature of ?0.6?K in a platinum-silicon interface. The interface was formed by using a unique focused ion beam sputtering micro-deposition method in which the energies of most sputtered Pt atoms are ?2.5?eV. Structural and elemental analysis by transmission electron microscopy (TEM) and energy dispersive X-ray spectroscopy reveal a???7?nm interface layer with abundant Pt, which is the layer likely responsible for the superconducting transport behavior. Similar transport behavior was also observed in a gold-silicon interface prepared by the same technique, indicating the possible generality of this phenomenon.

  7. Operationalization of Basic Observables in Mechanics

    E-Print Network [OSTI]

    Hartmann, Bruno

    2015-01-01

    This novel approach to the foundation of the physical theory begins with thought experiments on measurement practice like Einstein for relativistic Kinematics. For a similar foundation of Dynamics one can start from Hermann von Helmholtz analysis of basic measurements. We define energy, momentum and mass from elemental ordering relations for "capability to execute work" and "impact" in a collision and apply Helmholtz program for quantification. From simple pre-theoretic (principle of inertia, impossibility of Perpetuum Mobile, relativity principle) and measurement methodical principles we derive all fundamental equations of Mechanics. We explain the mathematical formalism from the operationalization of basic observables.

  8. Observation of ?cJ decays to ??¯¯¯????

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

    Ablikim, M.; Achasov, M. N.; Ambrose, D. J.; An, F. F.; An, Q.; An, Z. H.; Bai, J. Z.; Ban, Y.; Becker, J.; Bennett, J. V.; et al

    2012-09-13

    Decays of the ?cJ states (J=0, 1, 2) to ??¯¯¯????, including processes with intermediate ?(1385), are studied through the E1 transition ?'???cJ using 106×10? ?' events collected with the BESIII detector at BEPCII. This is the first observation of ?cJ decays to the final state ??¯¯¯????. The branching ratio of the intermediate process ?cJ??(1385)±?¯¯¯(1385)? is also measured for the first time, and the results agree with the theoretical predictions based on the color-octet effect.

  9. Inflation models, spectral index and observational constraints

    E-Print Network [OSTI]

    Laura Covi

    2000-03-30

    We have evaluated the observational constraints on the spectral index $n$, in the context of a $\\Lambda$CDM model. For $n$ scale-independent, as predicted by most models of inflation, present data require $n\\simeq 1.0 \\pm 0.1$ at the 2-$\\sigma$ level. We have also studied the two-parameter scale-dependent spectral index, predicted by running-mass inflation models. Present data allow significant variation of $n$ in this case, within the theoretically preferred region of parameter space.

  10. Observations and simulations improve space weather models

    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 wouldMass mapSpeeding access to scienceSpeedingLightweight MaterialsGasObservation of

  11. ARM - PI Product - Niamey Dust Observations

    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 Comments?govInstrumentsnoaacrnBarrow, Alaska OutreachCalendar NSAProductsMerged and corrected 915Dust Observations

  12. First Observation of Plasmarons in Graphene

    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 Room NewsInformation Current HABFES OctoberEvanServices »First Observation of Plasmarons in

  13. First Observation of Plasmarons in Graphene

    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 Room NewsInformation Current HABFES OctoberEvanServices »First Observation of Plasmarons inFirst

  14. Category:Observation Wells | 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 ECoopButte County,Camilla, Georgia:GeothermalNEPA Environmental AnalysisObservation

  15. Observations and simulations improve space weather models

    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 Room NewsInformationJesseworkSURVEY UNIVERSEHowScientific andComplex Oak RidgeObservation of

  16. Suzaku Observations of Four Heavily Absorbed HMXBs

    E-Print Network [OSTI]

    D. C. Morris; R. K. Smith; C. B. Markwardt; R. F. Mushotzky; J. Tueller; T. R. Kallman; K. S. Dhuga

    2008-08-22

    We report on Suzaku observations of four unidentified sources from the INTEGRAL and Swift BAT Galactic plane surveys. All the sources have a large neutral hydrogen column density and are likely members of an emerging class of heavily absorbed high mass X-ray binary (HMXB) first identified in INTEGRAL observations. Two of the sources in our sample are approximately constant flux sources, one source shows periodic variation and one source exhibited a short, bright X-ray outburst. The periodicity is transient, suggesting it is produced by a neutron star in an elliptical orbit around a stellar wind source. We analyze the flaring source in several segments to look for spectral variation and discuss the implications of the findings for the nature of the source. We conclude that all four sources in our sample can be identified with the emerging class of highly absorbed HMXBs, that one is a newly identified transient X-ray pulsar and that at least one is a newly identified supergiant fast X-ray transient (SFXT).

  17. New Interpretation of the Observational Matter Asymmetry

    E-Print Network [OSTI]

    Cai, R G; Li, X Q; Wang, X; Cai, Rong-Gen; Li, Tong; Li, Xue-Qian; Wang, Xun

    2006-01-01

    Motivated by the AMS project, we assume that due to some reason which is not known so far, after the Big Bang or inflation epoch, antimatter was repelled onto one brane which is separated from our brane where all the observational matter resides. We suppose that there is a potential barrier at the brane boundary, which is similar to the surface tension for water membrane. The barrier prevents the mater particles to enter the space between two branes and jump from one brane to another. However, by the quantum tunnelling, a sizable anti-matter flux may come to our brane and be observed by the Alpha-Magnetic-Spectrometer (AMS). The matter and antimatter on the two branes attract each other via gravitational force. Following literature we consider a possibility that a scalar field existing in the space between the branes causes a Casimir effect which results in a repulsive force against the gravitation. We find that the Casimir force is much stronger than the gravitational force, as long as the separation of the ...

  18. Reported Significant Observation (RSO) studies. Revision 1

    SciTech Connect (OSTI)

    Eicher, R.W.

    1992-12-01

    The Reported Significant Observation (RSO) study used in the field of safety is an information-gathering technique where employee-participants describe situations they have personally witnessed involving good and bad practices and safe and unsafe conditions. This information is useful in the risk assessment process because it focuses on hazards and thereby facilitates their elimination. However, RSO cannot be the only component in a risk assessment program. Used by the Air Force in their aviation psychology program and further developed by John C. Flanagan, RSO is more commonly known as the ``Critical Incident Technique.`` However, the words ``Critical`` and ``Incident`` had other connotations in nuclear safety, prompting early users within the Aerojet Nuclear Company to coin the more fitting title of ``Reported Significant Observations.`` The technique spread slowly in the safety field primarily because the majority of users were researchers interested in after-the-fact data, with application to everyday problems and behavioral factors. RSO was formally recognized as a significant hazard reduction tool during the development of the Management Oversight and Risk Tree (MORT) program for the US Atomic Energy Commission. The Department of Energy (DOE) has, in turn, adopted MORT for its system safety program, and this has resulted in RSO being a modern and viable technique for DOE contractor safety programs.

  19. Swift observations of GRB050904: the most distant cosmic explosion ever observed

    E-Print Network [OSTI]

    G. Cusumano; V. Mangano; G. Chincarini; A. Panaitescu; D. N. Burrows; V. La Parola; T. Sakamoto; S. Campana; T. Mineo; G. Tagliaferri; L. Angelini; S. D. Barthelemy; A. P. Beardmore; P. T. Boyd; L. Cominsky; C. Gronwall; E. E. Fenimore; N. Gehrels; P. Giommi; M. Goad; K. Hurley; S. Immler; J. A. Kennea; K. O. Mason; F. Marshall; P. Meszaros; J. A. Nousek; J. P. Osborne; D. M. Palmer; P. W. A. Roming; A. Wells; N. E. White; B. Zhang

    2006-11-08

    Swift discovered the high redshift (z=6.29) GRB050904 with the Burst Alert Telescope (BAT) and began observing with its narrow field instruments 161 s after the burst onset. This gamma-ray burst is the most distant cosmic explosion ever observed. Because of its high redshift, the X-ray Telescope (XRT) and BAT simultaneous observations provide 4 orders of magnitude of spectral coverage (0.2-150 keV; 1.4-1090 keV in the source rest frame) at a very early source-frame time (22 s). GRB050904 was a long, multi-peaked, bright GRB with strong variability during its entire evolution. The light curve observed by the XRT is characterized by the presence of a long flaring activity lasting up to 1-2 hours after the burst onset in the burst rest frame, with no evidence of a smooth power-law decay following the prompt emission as seen in other GRBs. However, the BAT tail extrapolated to the XRT band joins the XRT early light curve and the overall behavior resembles that of a very long GRB prompt. The spectral energy distribution softens with time, with the photon index decreasing from -1.2 during the BAT observation to -1.9 at the end of the XRT observation. The dips of the late X-ray flares may be consistent with an underlying X-ray emission arising from the forward shock and with the properties of the optical afterglow reported by Tagliaferri et al. (2005b). We interpret the BAT and XRT data as a single continuous observation of the prompt emission from a very long GRB. The peculiarities observed in GRB050904 could be due to its origin within one of the first star-forming regions in the Universe; very low metallicities of the progenitor at these epochs may provide an explanation.

  20. Dark Energy: Observational Evidence and Theoretical Models

    E-Print Network [OSTI]

    B. Novosyadlyj; V. Pelykh; Yu. Shtanov; A. Zhuk

    2015-02-14

    The book elucidates the current state of the dark energy problem and presents the results of the authors, who work in this area. It describes the observational evidence for the existence of dark energy, the methods and results of constraining of its parameters, modeling of dark energy by scalar fields, the space-times with extra spatial dimensions, especially Kaluza---Klein models, the braneworld models with a single extra dimension as well as the problems of positive definition of gravitational energy in General Relativity, energy conditions and consequences of their violation in the presence of dark energy. This monograph is intended for science professionals, educators and graduate students, specializing in general relativity, cosmology, field theory and particle physics.

  1. Laser frequency combs for astronomical observations

    E-Print Network [OSTI]

    Tilo Steinmetz; Tobias Wilken; Constanza Araujo-Hauck; Ronald Holzwarth; Theodor W. Hänsch; Luca Pasquini; Antonio Manescau; Sandro D'Odorico; Michael T. Murphy; Thomas Kentischer; Wolfgang Schmidt; Thomas Udem

    2008-09-09

    A direct measurement of the universe's expansion history could be made by observing in real time the evolution of the cosmological redshift of distant objects. However, this would require measurements of Doppler velocity drifts of about 1 centimeter per second per year, and astronomical spectrographs have not yet been calibrated to this tolerance. We demonstrate the first use of a laser frequency comb for wavelength calibration of an astronomical telescope. Even with a simple analysis, absolute calibration is achieved with an equivalent Doppler precision of approximately 9 meters per second at about 1.5 micrometers - beyond state-of-the-art accuracy. We show that tracking complex, time-varying systematic effects in the spectrograph and detector system is a particular advantage of laser frequency comb calibration. This technique promises an effective means for modeling and removal of such systematic effects to the accuracy required by future experiments to see direct evidence of the universe's putative acceleration.

  2. Observables from a relativistic hydro solution

    E-Print Network [OSTI]

    Csanad, Mate

    2009-01-01

    In the last several years it has been revealed that the matter produced in the collisions of the Relativistic Heavy Ion Collider (RHIC) is a nearly perfect fluid, i.e. it can be described with perfect fluid hydrodynamics. There was a long search for exact hydrodynamic models (solutions of the partial differential equations of hydrodynamics) and several models proved to be applicable. There are 1+3 dimensional models, as well as relativistic models - but no 1+3 dimensional and relativistic model has been tested yet. In this paper we extract observables from the relativistic, ellipsoidally symmetric model of Csorgo et al. We calculate momentum distribution, elliptic flow and correlation radii and compare them to RHIC data.

  3. Physics Beyond the Single Top Quark Observation

    SciTech Connect (OSTI)

    Heinson, A.P.; Collaboration, for the DZero

    2010-10-01

    In March 2009, the D0 Collaboration first observed the electroweak production of single top quarks at 5{sigma} significance. We measured the cross section for the combined s-channel and t-channel production modes, and set a lower limit on the CKM matrix element |V{sub tb}|. Since then, we have used the same dataset to measure the t-channel production mode independently, the combined cross section in the hadronically-decaying tau lepton final state, and the width and lifetime of the top quark, and we have set upper limits on contributions from anomalous flavor-changing neutral currents. This paper describes these new measurements, as presented at the 3rd International Workshop on Top Quark Physics, held in Brugge, Belgium, May 31-June 4, 2010.

  4. Interstellar water chemistry: from laboratory to observations

    E-Print Network [OSTI]

    van Dishoeck, Ewine F; Neufeld, David A

    2013-01-01

    Water is observed throughout the universe, from diffuse interstellar clouds to protoplanetary disks around young stars, and from comets in our own solar system and exoplanetary atmospheres to galaxies at high redshifts. This review summarizes the spectroscopy and excitation of water in interstellar space as well as the basic chemical processes that form and destroy water under interstellar conditions. Three major routes to water formation are identified: low temperature ion-molecule chemistry, high-temperature neutral-neutral chemistry and gas-ice chemistry. The rate coefficients of several important processes entering the networks are discussed in detail; several of them have been determined only in the last decade through laboratory experiments and theoretical calculations. Astronomical examples of each of the different chemical routes are presented using data from powerful new telescopes, in particular the Herschel Space Observatory. Basic chemical physics studies remain critically important to analyze ast...

  5. Astronomical Observations of Volatiles on Asteroids

    E-Print Network [OSTI]

    Rivkin, Andrew S; Emery, Joshua P; Howell, Ellen S; Licandro, Javier; Takir, Driss; Vilas, Faith

    2015-01-01

    We have long known that water and hydroxyl are important components in meteorites and asteroids. However, in the time since the publication of Asteroids III, evolution of astronomical instrumentation, laboratory capabilities, and theoretical models have led to great advances in our understanding of H2O/OH on small bodies, and spacecraft observations of the Moon and Vesta have important implications for our interpretations of the asteroidal population. We begin this chapter with the importance of water/OH in asteroids, after which we will discuss their spectral features throughout the visible and near-infrared. We continue with an overview of the findings in meteorites and asteroids, closing with a discussion of future opportunities, the results from which we can anticipate finding in Asteroids V. Because this topic is of broad importance to asteroids, we also point to relevant in-depth discussions elsewhere in this volume.

  6. Head Observation Organizer (HObO)

    SciTech Connect (OSTI)

    Steven Predmore

    2008-03-06

    The Head Observation Organizer, HObO, is a computer program that stores and manages measured ground-water levels. HObO was developed to help ground-water modelers compile, manage, and document water-level data needed to calibrate ground-water models. Well-construction and water-level data from the U.S. Geological Survey National Water Database (NWIS) easily can be imported into HObO from the NWIS web site (NWISWeb). The water-level data can be flagged to determine which data will be included in the calibration data set. The utility program HObO_NWISWeb was developed to simplify the down loading of well and water-level data from NWISWeb. An ArcGIS NWISWeb Extension was developed to retrieve site information from NWISWeb. A tutorial is presented showing the basic elements of HObO.

  7. First observation of doubly charmed baryons

    SciTech Connect (OSTI)

    M. A. Moinester et al.

    2003-09-25

    The SELEX experiment (E781) at Fermilab has observed two statistically compelling high mass states near 3.6 GeV/c{sup 2}, decaying to {Lambda}{sub c}{sup +} K{sup -} {pi}{sup +} and {Lambda}{sub c}{sup +} K{sup -} {pi}{sup +}{pi}{sup +}. These final states are Cabibbo-allowed decay modes of doubly charmed baryons {Xi}{sub cc}{sup +} and {Xi}{sub cc}{sup ++}, respectively. The masses are in the range expected from theoretical considerations, but the spectroscopy is surprising. SELEX also has weaker preliminary evidence for a state near 3.8 GeV/c{sup 2}, a high mass state decaying to {Lambda}{sub c}{sup +} K{sup -} {pi}{sup +}{pi}{sup +}, possibly an excited {Xi}{sub cc}{sup ++} (ccu*). Data are presented and discussed.

  8. Global Volunteer Observing Ship (VOS) Program Data

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

    CDIAC provides data management support for the Global Volunteer Observing Ship (VOS) Program. The VOS project is coordinated by the UNESCO International Ocean Carbon Coordination Project (IOCCP). The international groups from 14 countries have been outfitting research ships and commercial vessels with automated CO2 sampling equipment to analyze the carbon exchange between the ocean and atmosphere. [copied from http://cdiac.ornl.gov/oceans/genInfo.html] CDIAC provides a map interface with the shipping routes of the 14 countries involved marked in different colors. Clicking on the ship's name on that route brings up information about the vessel, the kinds of measurements collected and the timeframe, links to project pages, and, most important, the links to the data files themselves. The 14 countries are: United States, United Kingdom, Japan, France, Germany, Australia, Canada, Spain, Norway, New Zealand, China (including Taiwan), Iceland, and the Netherlands. Both archived and current, underway data can be accessed from the CDIAC VOS page.

  9. Remarks on mechanical approach to observable Universe

    SciTech Connect (OSTI)

    Eingorn, Maxim [CREST and NASA Research Centers, North Carolina Central University, Fayetteville st. 1801, Durham, North Carolina 27707 (United States); Zhuk, Alexander, E-mail: maxim.eingorn@gmail.com, E-mail: ai.zhuk2@gmail.com [Astronomical Observatory, Odessa National University, Dvoryanskaya st. 2, Odessa 65082 (Ukraine)

    2014-05-01

    We consider the Universe deep inside the cell of uniformity. At these scales, the Universe is filled with inhomogeneously distributed discrete structures (galaxies, groups and clusters of galaxies), which perturb the background Friedmann model. Here, the mechanical approach (Eingorn and Zhuk, 2012) is the most appropriate to describe the dynamics of the inhomogeneities which is defined, on the one hand, by gravitational potentials of inhomogeneities and, on the other hand, by the cosmological expansion of the Universe. In this paper, we present additional arguments in favor of this approach. First, we estimate the size of the cell of uniformity. With the help of the standard methods of statistical physics and for the galaxies of the type of the Milky Way and Andromeda, we get that it is of the order of 190 Mpc which is rather close to observations. Then, we show that the nonrelativistic approximation (with respect to the peculiar velocities) is valid for z?<10, i.e. approximately for 13 billion years from the present moment. We consider scalar perturbations and, within the ?CDM model, justify the main equations. Moreover, we demonstrate that radiation can be naturally incorporated into our scheme. This emphasizes the viability of our approach. This approach gives a possibility to analyze different cosmological models and compare them with the observable Universe. For example, we indicate some problematic aspects of the spatially flat models. Such models require a rather specific distribution of the inhomogeneities to get a finite potential at any points outside gravitating masses. We also criticize the application of the Schwarzschild-de Sitter solution to the description of the motion of test bodies on the cosmological background.

  10. Constraint effects observed in crack initiation stretch

    SciTech Connect (OSTI)

    Lambert, D.M.; Ernst, H.A.

    1995-12-31

    The current paper characterizes constraint in fracture: J-modified resistance (Jr) curves were developed for two tough structural materials, 6061-T651 (aluminum) and IN718-STA1 (nickel-base superalloy). A wide variety of configurations was tested to consider load configurations from bending to tension including three specimen types (compact tension, center-crack tension, and single-edge notched tension), and a range of ligament lengths and thicknesses, as well as side-grooved and smooth-sided ligaments. The Jr curves exhibited an inflection point after some crack extension, and the data were excluded beyond the inflection. Qualified Jr curves for the two materials showed similar behavior, but R-curves were identical for equal ligament length-to-thickness ratio (RL), for the aluminum alloy, with increasing slope for increasing RL, while for the nickel, the resistance curves aligned for equal ligament thickness, B, and the slope increased for decreasing B. Displacements at the original crack tip (CToD) were recorded throughout the test for several specimens. CToD-versus-crack extension curves were developed, and data were excluded beyond the inflection point (as with the Jr curves). The data collapsed into two distinct curves, thought to represent the surface, plane stress effect and the central, plane strain effect. This was observed for both materials. A technique called profiling is presented for the aluminum alloy only, where the crack face displacements are recorded at the final point of the test as a function of the position throughout the crack cavity, along with an effort to extract the observations in a usable form. Displacements were consistent throughout the cross-section at and behind the original crack tip. In the region where the crack grew, this displacement was developed by a combination of stretch and crack growth. The stretch required to initiate crack extension was a function of the depth beneath the surface into the cross-section.

  11. SPITZER OBSERVATIONS OF HOTSPOTS IN RADIO LOBES

    SciTech Connect (OSTI)

    Werner, Michael W.; Murphy, David W.; Livingston, John H.; Gorjian, Varoujan; Jones, Dayton L.; Meier, David L.; Lawrence, Charles R. [Jet Propulsion Laboratory, 4800 Oak Grove Drive, Pasadena, CA 91109 (United States)

    2012-11-10

    We have carried out a systematic search with Spitzer Warm Mission and archival data for infrared emission from the hotspots in radio lobes that have been described by Hardcastle et al. These hotspots have been detected with both radio and X-ray observations, but an observation at an intermediate frequency in the infrared can be critical to distinguish between competing models for particle acceleration and radiation processes in these objects. Between the archival and warm mission data, we report detections of 18 hotspots; the archival data generally include detections at all four IRAC bands, the Warm Mission data only at 3.6 {mu}m. Using a theoretical formalism adopted from Godfrey et al., we fit both archival and warm mission spectral energy distributions (SEDs)-including radio, X-ray, and optical data from Hardcastle as well as the Spitzer data-with a synchrotron self-Compton (SSC) model, in which the X-rays are produced by Compton scattering of the radio frequency photons by the energetic electrons which radiate them. With one exception, an SSC model requires that the magnetic field be less or much less than the equipartition value which minimizes total energy and has comparable amounts of energy in the magnetic field and in the energetic particles. This conclusion agrees with those of comparable recent studies of hotspots, and with the analysis presented by Hardcastle et al. We also show that the infrared data rule out the simplest synchrotron-only models for the SEDs. We briefly discuss the implications of these results and of alternate interpretations of the data.

  12. Observation of the Second Harmonic in Thomson Scattering from...

    Office of Scientific and Technical Information (OSTI)

    Observation of the Second Harmonic in Thomson Scattering from Relativistic Electrons Citation Details In-Document Search Title: Observation of the Second Harmonic in Thomson...

  13. Collaboration yields 'The Right Glasses' for observing mystery...

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

    Observing mystery behavior In electrons Collaboration yields 'The Right Glasses' for observing mystery behavior in electrons The research may lead to a better understanding of...

  14. Net Zero Waste - Tools and Technical Support ...and other observations...

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

    Net Zero Waste - Tools and Technical Support ...and other observations Net Zero Waste - Tools and Technical Support ...and other observations Presentation at Waste-to-Energy using...

  15. If physics is an information science, what is an observer?

    E-Print Network [OSTI]

    Chris Fields

    2012-02-11

    Interpretations of quantum theory have traditionally assumed a "Galilean" observer, a bare "point of view" implemented physically by a quantum system. This paper investigates the consequences of replacing such an informationally-impoverished observer with an observer that satisfies the requirements of classical automata theory, i.e. an observer that encodes sufficient prior information to identify the system being observed and recognize its acceptable states. It shows that with reasonable assumptions about the physical dynamics of information channels, the observations recorded by such an observer will display the typical characteristics predicted by quantum theory, without requiring any specific assumptions about the observer's physical implementation.

  16. Direct observation of resistive heating at graphene wrinkles...

    Office of Scientific and Technical Information (OSTI)

    Direct observation of resistive heating at graphene wrinkles and grain boundaries Citation Details In-Document Search Title: Direct observation of resistive heating at graphene...

  17. Observational Tests and Predictive Stellar Evolution

    E-Print Network [OSTI]

    P. A. Young; E. E. Mamajek; David Arnett; James Liebert

    2001-03-23

    We compare eighteen binary systems with precisely determined radii and masses from 23 to 1.1 M_sol, and stellar evolution models produced with our newly revised code TYCHO. ``Overshooting'' and rotational mixing were suppressed in order to establish a baseline for isolating these and other hydrodynamic effects. Acceptable coeval fits are found for sixteen pairs without optimizing for heavy element or helium abundance. The precision of these tests is limited by the accuracies of the observed effective temperatures. High dispersion spectra and detailed atmospheric modeling should give more accurate effective temperatures and heavy element abundances. PV Cas, a peculiar early A system, EK Cep B, a known post-T Tauri star, and RS Cha, a member of a young OB association, are matched by pre-main sequence models. Predicted mass loss agrees with upper limits from IUE for CW Cep A and B. Relatively poor fits are obtained for binaries having at least one component in the mass range 1.7 < M/M_sol <2.6, whose evolution is sensitive to mixing. These discrepancies are robust and consistent with additional mixing in real stars. The predicted apsidal motion implies that massive star models are systematically less centrally condensed than the real stars. If these effects are due to overshooting, then the overshooting parameter alpha_OV increases with stellar mass. The apsidal motion constants are controlled by radiative opacity under conditions close to those directly measured in laser experiments, making this test more stringent than possible before.

  18. MAGIC observation of the GRB080430 afterglow

    E-Print Network [OSTI]

    Aleksi?, J; Antonelli, L A; Antoranz, P; Backes, M; Baixeras, C; Balestra, S; Barrio, J A; Bastieri, D; González, J Becerra; Becker, J K; Bednarek, W; Berdyugin, A; Berger, K; Bernardini, E; Biland, A; Bock, R K; Bonnoli, G; Bordas, P; Tridon, D Borla; Bosch-Ramon, V; Bose, D; Braun, I; Bretz, T; Britzger, D; Camara, M; Carmona, E; Carosi, A; Colin, P; Commichau, S; Contreras, J L; Cortina, J; Costado, M T; Covino, S; Dazzi, F; De Angelis, A; del Pozo, E de Cea; Reyes, R De los; De Lotto, B; De Maria, M; De Sabata, F; Mendez, C Delgado; Doert, M; Domínguez, A; Prester, D Dominis; Dorner, D; Doro, M; Elsaesser, D; Errando, M; Ferenc, D; Fernández, E; Firpo, R; Fonseca, M V; Font, L; Galante, N; López, R J García; Garczarczyk, M; Gaug, M; Godinovic, N; Goebel, F; Hadasch, D; Herrero, A; Hildebrand, D; Höhne-Mönch, D; Hose, J; Hrupec, D; Hsu, C C; Jogler, T; Klepser, S; Krähenbühl, T; Kranich, D; La Barbera, A; Laille, A; Leonardo, E; Lindfors, E; Lombardi, S; Longo, F; López, M; Lorenz, E; Majumdar, P; Maneva, G; Mankuzhiyil, N; Mannheim, K; Maraschi, L; Mariotti, M; Martínez, M; Mazin, D; Meucci, M; Miranda, J M; Mirzoyan, R; Miyamoto, H; Moldón, J; Moles, M; Moralejo, A; Nieto, D; Nilsson, K; Ninkovic, J; Orito, R; Oya, I; Paoletti, R; Paredes, J M; Pasanen, M; Pascoli, D; Pauss, F; Pegna, R G; Perez-Torres, M A; Persic, M; Peruzzo, L; Prada, F; Prandini, E; Puchades, N; Puljak, I; Reichardt, I; Rhode, W; Ribó, M; Rico, J; Rissi, M; Rügamer, S; Saggion, A; Saito, T Y; Salvati, M; Sánchez-Conde, M; Satalecka, K; Scalzotto, V; Scapin, V; Schweizer, T; Shayduk, M; Shore, S N; Sierpowska-Bartosik, A; Sillanpää, A; Sitarek, J; Sobczynska, D; Spanier, F; Spiro, S; Stamerra, A; Steinke, B; Strah, N; Struebig, J C; Suric, T; Takalo, L; Tavecchio, F; Temnikov, P; Tescaro, D; Teshima, M; Torres, D F; Turini, N; Vankov, H; Wagner, R M; Zabalza, V; Zandanel, F; Zanin, R; Zapatero, J; de Ugarte-Postigo, A

    2015-01-01

    Context: Gamma-ray bursts are cosmological sources emitting radiation from the gamma-rays to the radio band. Substantial observational efforts have been devoted to the study of gamma-ray bursts during the prompt phase, i.e. the initial burst of high-energy radiation, and during the long-lasting afterglows. In spite of many successes in interpreting these phenomena, there are still several open key questions about the fundamental emission processes, their energetics and the environment. Aim: Independently of specific gamma-ray burst theoretical recipes, spectra in the GeV/TeV range are predicted to be remarkably simple, being satisfactorily modeled with power-laws, and therefore offer a very valuable tool to probe the extragalactic background light distribution. Furthermore, the simple detection of a component at very-high energies, i.e. at $\\sim 100$\\,GeV, would solve the ambiguity about the importance of various possible emission processes, which provide barely distinguishable scenarios at lower energies. Me...

  19. Chandra Observations of SNR RCW 103

    E-Print Network [OSTI]

    Frank, Kari A; Park, Sangwook

    2015-01-01

    We analyze three Chandra observations, with a combined exposure time of 99 ks, of the Galactic supernova remnant RCW 103, a young supernova remnant, previously with no clear detection of metal-rich ejecta. Based on our imaging and spectral analyses of these deep Chandra data, we find evidence for metal-rich ejecta emission scattered throughout the remnant. X-ray emission from the shocked ejecta is generally weak, and the shocked circumstellar medium (CSM) is a largely dominant component across the entire remnant. The CSM component shows abundances of ~0.5 solar, while Ne, Mg, Si, S, and Fe abundances of the ejecta are up to a few times solar. Comparison of these ejecta abundances with yields from supernova nucleosynthesis models suggests, together with the existence of a central neutron star, a progenitor mass of ~18-20 M$_\\odot$, though the Fe/Si ratios are larger than predicted. The shocked CSM emission suggests a progenitor with high mass-loss rate and subsolar metallicity.

  20. Observation of Bloch oscillations in molecular rotation

    E-Print Network [OSTI]

    Johannes Floß; Andrei Kamalov; Ilya Sh. Averbukh; Philip H. Bucksbaum

    2015-04-26

    The periodically kicked quantum rotor is known for non-classical effects such as quantum localisation in angular momentum space or quantum resonances in rotational excitation. These phenomena have been studied in diverse systems mimicking the kicked rotor, such as cold atoms in optical lattices, or coupled photonic structures. Recently, it was predicted that several solid state quantum localisation phenomena - Anderson localisation, Bloch oscillations, and Tamm-Shockley surface states - may manifest themselves in the rotational dynamics of laser-kicked molecules. Here, we report the first observation of rotational Bloch oscillations in a gas of nitrogen molecules kicked by a periodic train of femtosecond laser pulses. A controllable detuning from the quantum resonance creates an effective accelerating potential in angular momentum space, inducing Bloch-like oscillations of the rotational excitation. These oscillations are measured via the temporal modulation of the refractive index of the gas. Our results introduce room-temperature laser-kicked molecules as a new laboratory for studies of localisation phenomena in quantum transport.

  1. Optical monitor for observing turbulent flow

    DOE Patents [OSTI]

    Albrecht, Georg F. (Livermore, CA); Moore, Thomas R. (Rochester, NY)

    1992-01-01

    The present invention provides an apparatus and method for non-invasively monitoring turbulent fluid flows including anisotropic flows. The present invention uses an optical technique to filter out the rays travelling in a straight line, while transmitting rays with turbulence induced fluctuations in time. The output is two dimensional, and can provide data regarding the spectral intensity distribution, or a view of the turbulence in real time. The optical monitor of the present invention comprises a laser that produces a coherent output beam that is directed through a fluid flow, which phase-modulates the beam. The beam is applied to a temporal filter that filters out the rays in the beam that are straight, while substantially transmitting the fluctuating, turbulence-induced rays. The temporal filter includes a lens and a photorefractive crystal such as BaTiO.sub.3 that is positioned in the converging section of the beam near the focal plane. An imaging system is used to observe the filtered beam. The imaging system may take a photograph, or it may include a real time camera that is connected to a computer. The present invention may be used for many purposes including research and design in aeronautics, hydrodynamics, and combustion.

  2. Swift observations of GRB050904: the most distant cosmic explosion ever observed

    E-Print Network [OSTI]

    Cusumano, G; Chincarini, G; Panaitescu, A; Burrows, D N; La Parola, V; Sakamoto, T; Campana, S; Mineo, T; Tagliaferri, G; Angelini, L; Barthelemy, S D; Beardmore, A P; Boyd, P T; Cominsky, L; Gronwall, C; Fenimore, E E; Gehrels, N; Giommi, P; Goad, M; Hurley, K; Immler, S; Kennea, J A; Mason, K O; Marshall, F; Mészáros, P; Nousek, J A; Osborne, J P; Palmer, D M; Roming, P W A; Wells, A; White, N E; Zhang, B

    2006-01-01

    Swift discovered the high redshift (z=6.29) GRB050904 with the Burst Alert Telescope (BAT) and began observing with its narrow field instruments 161 s after the burst onset. This gamma-ray burst is the most distant cosmic explosion ever observed. Because of its high redshift, the X-ray Telescope (XRT) and BAT simultaneous observations provide 4 orders of magnitude of spectral coverage (0.2-150 keV; 1.4-1090 keV in the source rest frame) at a very early source-frame time (22 s). GRB050904 was a long, multi-peaked, bright GRB with strong variability during its entire evolution. The light curve observed by the XRT is characterized by the presence of a long flaring activity lasting up to 1-2 hours after the burst onset in the burst rest frame, with no evidence of a smooth power-law decay following the prompt emission as seen in other GRBs. However, the BAT tail extrapolated to the XRT band joins the XRT early light curve and the overall behavior resembles that of a very long GRB prompt. The spectral energy distri...

  3. A Method for Weak Lensing Observations

    E-Print Network [OSTI]

    Nick Kaiser; Gordon Squires; Tom Broadhurst

    1994-11-01

    We develop and test a method for measuring the gravitational lensing induced distortion of faint background galaxies. We first describe how we locate the galaxies and measure a 2-component `polarisation' or ellipticity statistic $e_\\alpha$ whose expectation value should be proportional to the gravitational shear $\\gamma_\\alpha$. We then show that an anisotropic instrumental psf perturbs the polarisation by $\\delta e_\\alpha = P^s_{\\alpha\\beta} p_\\beta$, where $p_\\alpha$ is a measure of the psf anisotropy and $P^s_{\\alpha\\beta}$ is the `linearised smear polarisability tensor'. By estimating $P^s_{\\alpha\\beta}$ for each object we can determine $p_\\alpha$ from the foreground stars and apply a correction $-P^s_{\\alpha\\beta}p_\\beta$ to the galaxies. We test this procedure using deep high-resolution images from HST which are smeared with an anisotropic psf and then have noise added to simulate ground-based observations. We find that the procedure works very well. A similar analysis yields a linear shear polarisability tensor $P^\\gamma_{\\alpha\\beta}$ which describes the response to a gravitational shear. This calibrates the polarisation-shear relation, but only for galaxies which are well resolved. To empirically calibrate the effect of seeing on the smaller galaxies we artificially stretch HST images to simulate lensing and then degrade them as before. These experiments provide a rigorous and exacting test of the method under realistic conditions. They show that it is possible to remove the effect of instrumental psf anisotropy, and that the method provides an efficient and quantitative measurement of the gravitational shear.

  4. Observers and the AdS/CFT correspondence

    E-Print Network [OSTI]

    M. Dance

    2010-12-18

    The paper \\cite{Dance0601} tentatively suggested a physical picture that might underlie string theories. The string parameters $\\tau $ and $\\sigma_i $ were interpreted as spacetime dimensions which a simple quantum mechanical observer can observe, while symmetries of the relevant observer states could limit the observability of other dimensions. The present paper extends the discussion by outlining how consideration of different observers, at least one of which is quantum mechanical, might provide insights into the nature of the AdS/CFT correspondence. It is suggested that such correspondences might arise as different forms of theories about the world as perceived by different observers.

  5. Optimization of the transmission of observable expectation values and observable statistics in Continuous Variable Teleportation

    E-Print Network [OSTI]

    L. Albano Farias; J. Stephany

    2010-09-28

    We analyze the statistics of observables in continuous variable quantum teleportation in the formalism of the characteristic function. We derive expressions for average values of output state observables in particular cumulants which are additive in terms of the input state and the resource of teleportation. Working with Squeezed Bell-like states, which may be optimized in a free parameter for better teleportation performance we discuss the relation between resources optimal for fidelity and for different observable averages. We obtain the values of the free parameter which optimize the central momenta and cumulants up to fourth order. For the cumulants the distortion between in and out states due to teleportation depends only on the resource. We obtain optimal parameters for the second and fourth order cumulants which do not depend on the squeezing of the resource. The second order central momenta which is equal to the second order cumulants and the photon number average are optimized by the same resource. We show that the optimal fidelity resource, found in reference (Phys. Rev. A {\\bf 76}, 022301 (2007)) to depend also on the characteristics of input, tends for high squeezing to the resource which optimizes the second order momenta. A similar behavior is obtained for the resource which optimizes the photon statistics which is treated here using the sum of the squared differences in photon probabilities of input and output states as the distortion measure. This is interpreted to mean that the distortions associated to second order momenta dominates the behavior of the output state for large squeezing of the resource. Optimal fidelity and optimal photon statistics resources are compared and is shown that for mixtures of Fock states they are equivalent.

  6. INFRARED OBSERVATIONS OF VOLATILE MOLECULES IN COMET HALEBOPP

    E-Print Network [OSTI]

    Meyer-Vernet, Nicole

    ­slit spectroscopy --- of the space distribution of these species. With ISO, carbon dioxide was directly observed case the only remote­ sensing technique allowing to observe non­polar molecules such as CO 2

  7. Zeroth-order inversion of transient head observations

    E-Print Network [OSTI]

    Vasco, D.W.

    2008-01-01

    The hydraulic head was observed in seven surrounding wellsHydraulic conductivity variation used for numerical trajectory computations. The wellhydraulic conductivity, given the significant variations in travel time to the observation wells.

  8. Observed Relations Between Snowfall Microphysics and Triple-Frequency Radar Observations

    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 wouldMass mapSpeeding access to scienceSpeedingLightweight MaterialsGasObservationRelations

  9. The Pegg-Barnett Formalism and Covariant Phase Observables

    E-Print Network [OSTI]

    Pekka Lahti; Juha-Pekka Pellonpaa

    2001-06-15

    We compare the Pegg-Barnett (PB) formalism with the covariant phase observable approach to the problem of quantum phase and show that PB-formalism gives essentially the same results as the canonical (covariant) phase observable. We also show that PB-formalism can be extended to cover all covariant phase observables including the covariant phase observable arising from the angle margin of the Husimi Q-function.

  10. EuropeanGridofSolarObservations Progress on the

    E-Print Network [OSTI]

    ;EuropeanGridofSolarObservations Some generic issues We need to build on the existing situation UserEuropeanGridofSolarObservations Progress on the European Grid of Solar Observations R.D. Bentley Mullard Space Science Laboratory University College London FASR Workshop #12;EuropeanGridofSolar

  11. FACULTY OF GEO-INFORMATION SCIENCE AND EARTH OBSERVATION

    E-Print Network [OSTI]

    FACULTY OF GEO-INFORMATION SCIENCE AND EARTH OBSERVATION ITC research Space for global development. At the Faculty of Geo-Information Science and Earth Observation (ITC) of the University of Twente, knowledge;2 At the Faculty of Geo-Information Science and Earth Observation (ITC) of the University of Twente, research

  12. Test, debug and development environment of Subaru Observation Software System

    E-Print Network [OSTI]

    Hayashi, Saeko S.

    - 1/7 - Test, debug and development environment of Subaru Observation Software System Junichi have a computer system in Japan which simulates the network of the summit system in part. Software test, Japan ABSTRACT Subaru Observation Software System (SOSS) provides observers with so called high

  13. SM EFT -connect UV models to precision observables Xiaochuan Lu

    E-Print Network [OSTI]

    Murayama, Hitoshi

    observables UV models Connect Models to Measurements How do the precision measurements shed light on physics observables UV models Connect Models to Measurements How do the precision measurements shed light on physics Berkeley 14 Precision observables UV models Connect Models to Measurements How do the precision

  14. RECORDS AND OBSERVATIONS FROM PLANKTON GRID STUDIES OFF BAJA

    E-Print Network [OSTI]

    422 RECORDS AND OBSERVATIONS FROM PLANKTON GRID STUDIES OFF BAJA CALIFORNIA, APRIL 1952 SPECIAL AND OBSERVATIONS FROM PLANKTON GRID STUDIES OFF BAJA CALIFORNIA, APRIL 1952 by David Kramer United States Fish volumes 21 Literature cited 42 Hi #12;#12;RECORDS AND OBSERVATIONS FROM PLANKTON GRID STUDIES OFF BAJA

  15. Partial and Complete Observables for Canonical General Relativity

    E-Print Network [OSTI]

    B. Dittrich

    2005-07-25

    In this work we will consider the concepts of partial and complete observables for canonical general relativity. These concepts provide a method to calculate Dirac observables. The central result of this work is that one can compute Dirac observables for general relativity by dealing with just one constraint. For this we have to introduce spatial diffeomorphism invariant Hamiltonian constraints. It will turn out that these can be made to be Abelian. Furthermore the methods outlined here provide a connection between observables in the space--time picture, i.e. quantities invariant under space--time diffeomorphisms, and Dirac observables in the canonical picture.

  16. Sloan Digital Sky Survey observing time tracking and efficiency measurement

    SciTech Connect (OSTI)

    Eric H. Neilsen, Jr.; Richard G. Kron; William N. Boroski

    2002-10-16

    Accurate and consistent time tracking is essential for evaluating the efficiency of survey observing operations and identifying areas that need improvement. Off the shelf time tracking software, which requires users to enter activities by hand, proved tedious to use and insufficiently exible. In this paper, we present an alternate time tracking system developed specifically for Sloan Digital Sky Survey observing. This system uses an existing logging system, murmur, to log the beginning and ending times of tracked circumstances, including activities, weather, and problems which effect observing. Operations software automatically generates most entries for routine observing activities; in a night of routine observing, time tracking requires little or no attention from the observing staff. A graphical user interface allows observers to make entries marking time lost to weather and equipment, and to correct inaccurate entries made by the observing software. The last is necessary when the change in activity is not marked by a change in the state of the software or instruments, or when the time is used for engineering or other observing not part of routine survey data collection. A second utility generates reports of time usage from these logs. These reports include totals for the time spent for each observing task, time lost to weather and problems, efficiency statistics for comparison with the survey baseline, and a detailed listing of what activities and problems were present in any covered time period.

  17. Observability and Controllability of Nonlinear Networks: The Role of Symmetry

    E-Print Network [OSTI]

    Andrew J. Whalen; Sean N. Brennan; Timothy D. Sauer; Steven J. Schiff

    2014-10-06

    Observability and controllability are essential concepts to the design of predictive observer models and feedback controllers of networked systems. For example, noncontrollable mathematical models of real systems have subspaces that influence model behavior, but cannot be controlled by an input. Such subspaces can be difficult to determine in complex nonlinear networks. Since almost all of the present theory was developed for linear networks without symmetries, here we present a numerical and group representational framework, to quantify the observability and controllability of nonlinear networks with explicit symmetries that shows the connection between symmetries and nonlinear measures of observability and controllability. We numerically observe and theoretically predict that not all symmetries have the same effect on network observation and control. Our analysis shows that the presence of symmetry in a network may decrease observability and controllability, although networks containing only rotational symmetries remain controllable and observable. These results alter our view of the nature of observability and controllability in complex networks, change our understanding of structural controllability, and affect the design of mathematical models to observe and control such networks.

  18. NS&T Managment Observations - 1st Quarter

    SciTech Connect (OSTI)

    David Gianotto

    2014-06-01

    The INL Management Observation Program (MOP) is designed to improve managers and supervisors understanding of work being performed by employees and the barriers impacting their success. The MOP also increases workers understanding of managements’ expectations as they relate to safety, security, quality, and work performance. Management observations (observations) are designed to improve the relationship and trust between employees and managers through increased engagement and interactions between managers and researchers in the field. As part of continuous improvement, NS&T management took initiative to focus on the participation and quality of observations in FY 14. This quarterly report is intended to (a) summarize the participation and quality of management’s observations, (b) assess observations for commonalities or trends related to facility or process barriers impacting research, and (c) provide feedback and make recommendations for improvements NS&T’s MOP.

  19. Observation of GRBs by the MAGIC Telescope, Status and Outlook

    E-Print Network [OSTI]

    D. Bastieri; N. Galante; M. Garczarczyk; M. Gaug; F. Longo; S. Mizobuchi; V. Scapin

    2007-09-10

    Observation of Gamma Ray Bursts (GRBs) in the Very High Energy (VHE) domain will provide important information on the physical conditions in GRB outflows. The MAGIC telescope is the best suited Imaging Atmospheric Cherenkov Telescope (IACT) for these observations. Thanks to its fast repositioning time and low energy threshold, MAGIC is able to start quickly the follow-up observation, triggered by an alert from the GRB Coordinates Network (GCN), and observe the prompt emission and early afterglow phase from GRBs. In the last two years of operation several GRB follow-up observations were performed by MAGIC, however, until now without successful detection of VHE gamma rays above threshold energies >100 GeV. In this paper we revise the expectations for the GRB observations with MAGIC, based on the experience from the last years of operation.

  20. Hawking radiation as perceived by different observers (ERE2011 proceedings)

    E-Print Network [OSTI]

    Barbado, Luis C; Garay, Luis J

    2012-01-01

    We study the perception of Hawking radiation by different observers outside a black hole. The analysis is done in terms of an effective-temperature function that varies along the trajectory of each observer. The vacuum state of the radiation field is chosen to be non-stationary, so as to mimic the switching-on of Hawking radiation that would appear in a real black hole collapse. We analyse how this vacuum is perceived by observers staying at a fixed radius, by observers coming in free-fall from radial infinity at different times, and by observers in free-fall released from finite radial positions. Results found have a compelling physical interpretation. One main result, at first unexpected, is that in general free-falling observers do perceive particle emission by the black hole when crossing the event horizon. This happens because of a diverging Doppler shift at the event horizon.

  1. Hawking radiation as perceived by different observers (ERE2011 proceedings)

    E-Print Network [OSTI]

    Luis C. Barbado; Carlos Barceló; Luis J. Garay

    2012-10-01

    We study the perception of Hawking radiation by different observers outside a black hole. The analysis is done in terms of an effective-temperature function that varies along the trajectory of each observer. The vacuum state of the radiation field is chosen to be non-stationary, so as to mimic the switching-on of Hawking radiation that would appear in a real black hole collapse. We analyse how this vacuum is perceived by observers staying at a fixed radius, by observers coming in free-fall from radial infinity at different times, and by observers in free-fall released from finite radial positions. Results found have a compelling physical interpretation. One main result, at first unexpected, is that in general free-falling observers do perceive particle emission by the black hole when crossing the event horizon. This happens because of a diverging Doppler shift at the event horizon.

  2. The HAWC Gamma-Ray Observatory: Observations of Cosmic Rays

    E-Print Network [OSTI]

    Abeysekara, A U; Alvarez, C; Álvarez, J D; Arceo, R; Arteaga-Velázquez, J C; Solares, H A Ayala; Barber, A S; Baughman, B M; Bautista-Elivar, N; Belmont, E; BenZvi, S Y; Berley, D; Rosales, M Bonilla; Braun, J; Caballero-Lopez, R A; Caballero-Mora, K S; Carramiñana, A; Castillo, M; Cotti, U; Cotzomi, J; de la Fuente, E; De León, C; DeYoung, T; Hernandez, R Diaz; Díaz-Vélez, J C; Dingus, B L; DuVernois, M A; Ellsworth, R W; Fernandez, A; Fiorino, D W; Fraija, N; Galindo, A; Garfias, F; González, L X; González, M M; Goodman, J A; Grabski, V; Gussert, M; Hampel-Arias, Z; Hui, C M; Hüntemeyer, P; Imran, A; Iriarte, A; Karn, P; Kieda, D; Kunde, G J; Lara, A; Lauer, R J; Lee, W H; Lennarz, D; Vargas, H León; Linares, E C; Linnemann, J T; Longo, M; Luna-GarcIa, R; Marinelli, A; Martinez, H; Martinez, O; Martínez-Castro, J; Matthews, J A J; Miranda-Romagnoli, P; Moreno, E; Mostafá, M; Nava, J; Nellen, L; Newbold, M; Noriega-Papaqui, R; Oceguera-Becerra, T; Patricelli, B; Pelayo, R; Pérez-Pérez, E G; Pretz, J; Rivière, C; Rosa-González, D; Salazar, H; Salesa, F; Sanchez, F E; Sandoval, A; Santos, E; Schneider, M; Silich, S; Sinnis, G; Smith, A J; Sparks, K; Springer, R W; Taboada, I; Toale, P A; Tollefson, K; Torres, I; Ukwatta, T N; Villaseñor, L; Weisgarber, T; Westerhoff, S; Wisher, I G; Wood, J; Yodh, G B; Younk, P W; Zaborov, D; Zepeda, A; Zhou, H

    2013-01-01

    We describe measurements of GeV and TeV cosmic rays with the High-Altitude Water Cherenkov Gamma-Ray Observatory, or HAWC. The measurements include the observation of the shadow of the moon; the observation of small-scale and large-scale angular clustering of the TeV cosmic rays; the prospects for measurement of transient solar events with HAWC; and the observation of Forbush decreases with the HAWC engineering array and HAWC-30.

  3. Transport Regulation from Theory to Practice: General Observations...

    Open Energy Info (EERE)

    Transport Regulation from Theory to Practice: General Observations and a Case Study Jump to: navigation, search Tool Summary LAUNCH TOOL Name: Transport Regulation from Theory to...

  4. Some Observations Regarding Steady Laminar Flows Past Bluff Bodies

    E-Print Network [OSTI]

    Fornberg, Bengt

    Some Observations Regarding Steady Laminar Flows Past Bluff Bodies Bengt Fornberg Department, 2013. February 4, 2014 Abstract Steady laminar flows past simple objects, such as a cylinder

  5. Sandia Energy - NASA Award for Marginal Ice Zone Observations...

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

    NASA Award for Marginal Ice Zone Observations and Process Experiment (MIZOPEX) Home Climate Office of Science News News & Events Research & Capabilities Monitoring Analysis...

  6. Simultaneous observation of nascent plasma and bubble induced...

    Office of Scientific and Technical Information (OSTI)

    Simultaneous observation of nascent plasma and bubble induced by laser ablation in water with various pulse durations Citation Details In-Document Search Title: Simultaneous...

  7. Magnetism and superconductivity observed to exist in harmony

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

    at Los Alamos National Laboratory, along with colleagues at institutions in Switzerland and Canada, have observed, for the first time in a single exotic phase, a situation...

  8. Sloan Digital Sky Survey photometric telescope automation and observing software

    SciTech Connect (OSTI)

    Eric H. Neilsen, Jr. et al.

    2002-10-16

    The photometric telescope (PT) provides observations necessary for the photometric calibration of the Sloan Digital Sky Survey (SDSS). Because the attention of the observing staff is occupied by the operation of the 2.5 meter telescope which takes the survey data proper, the PT must reliably take data with little supervision. In this paper we describe the PT's observing program, MOP, which automates most tasks necessary for observing. MOP's automated target selection is closely modeled on the actions a human observer might take, and is built upon a user interface that can be (and has been) used for manual operation. This results in an interface that makes it easy for an observer to track the activities of the automating procedures and intervene with minimum disturbance when necessary. MOP selects targets from the same list of standard star and calibration fields presented to the user, and chooses standard star fields covering ranges of airmass, color, and time necessary to monitor atmospheric extinction and produce a photometric solution. The software determines when additional standard star fields are unnecessary, and selects survey calibration fields according to availability and priority. Other automated features of MOP, such as maintaining the focus and keeping a night log, are also built around still functional manual interfaces, allowing the observer to be as active in observing as desired; MOP's automated features may be used as tools for manual observing, ignored entirely, or allowed to run the telescope with minimal supervision when taking routine data.

  9. AAO support observations for the Hubble Deep Field Sout

    E-Print Network [OSTI]

    B. J. Boyle

    1998-04-09

    We present proposed ground-based support observations at the AAO for the forthcoming Hubble Deep Field South (HDF-S) campaign.

  10. Intercomparison of model simulations of mixed-phase clouds observed...

    Office of Scientific and Technical Information (OSTI)

    Title: Intercomparison of model simulations of mixed-phase clouds observed during the ARM Mixed-Phase Arctic Cloud Experiment. Part I: Single layer cloud Results are presented...

  11. Pole placement design for quantum systems via coherent observers

    E-Print Network [OSTI]

    Zibo Miao; Matthew R. James; Valery A. Ugrinovskii

    2015-09-17

    We previously extended Luenberger's approach for observer design to the quantum case, and developed a class of coherent observers which tracks linear quantum stochastic systems in the sense of mean values. In light of the fact that the Luenberger observer is commonly and successfully applied in classical control, it is interesting to investigate the role of coherent observers in quantum feedback. As the first step in exploring observer-based coherent control, in this paper we study pole-placement techniques for quantum systems using coherent observers, and in such a fashion, poles of a closed-loop quantum system can be relocated at any desired locations. In comparison to classical feedback control design incorporating the Luenberger observer, here direct coupling between a quantum plant and the observer-based controller are allowed to enable a greater degree of freedom for the design of controller parameters. A separation principle is presented, and we show how to design the observer and feedback independently to be consistent with the laws of quantum mechanics. The proposed scheme is applicable to coherent feedback control of quantum systems, especially when the transient dynamic response is of interest, and this issue is illustrated in an example.

  12. Laboratory Investigation of Entrainment and Mixing in Oceanic Overflows

    E-Print Network [OSTI]

    Philippe, Odier; Ecke, Robert E

    2013-01-01

    We present experimental measurements of a wall-bounded gravity current, motivated by characterizing natural gravity currents such as oceanic overflows. We use particle image velocimetry and planar laser-induced fluorescence to simultaneously measure the velocity and density fields as they evolve downstream of the initial injection from a turbulent channel flow onto a plane inclined at 10$^\\circ$ with respect to horizontal. The turbulence level of the input flow is controlled by injecting velocity fluctuations upstream of the output nozzle. The initial Reynolds number based on Taylor microscale of the flow, R$_\\lambda$, is varied between 40 and 120, and the effects of the initial turbulence level are assessed. The bulk Richardson number $Ri$ for the flow is about 0.3 whereas the gradient Richardson number $Ri_g$ varies between 0.04 and 0.25, indicating that shear dominates the stabilizing effect of stratification. Kelvin-Helmholtz instability results in vigorous vertical transport of mass and momentum. We pres...

  13. Marine Biology International Journal on Life in Oceans

    E-Print Network [OSTI]

    Florida, University of

    . Murphy, Michael G. Frick, Annette C. Broderick, John W. Coker, Michael S. Coyne, Mark G. Dodd, et al. #12 · Michael G. Frick · Annette C. Broderick · John W. Coker · Michael S. Coyne · Mark G. Dodd · Matthew H) on the East Coast of the United States of America (30°480 N, 81°280 W to 33°510 N, 77°590 W). The majority

  14. Abundance and diversity of microbial life in ocean crust

    E-Print Network [OSTI]

    Moyer, Craig

    of microbes that are supported by basalt alteration is lacking. Here, using quantitative polymerase chain reaction, in situ hybridiza- tion and microscopy, we demonstrate that prokaryotic cell abun- dances these sites. We hypothesize that alteration reactions fuel chemolithoautotrophic microorganisms, which

  15. Warm Bias and Parameterization of Boundary Upwelling in Ocean Models

    SciTech Connect (OSTI)

    Cessi, Paola; Wolfe, Christopher

    2012-11-06

    It has been demonstrated that Eastern Boundary Currents (EBC) are a baroclinic intensification of the interior circulation of the ocean due to the emergence of mesoscale eddies in response to the sharp buoyancy gradients driven by the wind-stress and the thermal surface forcing. The eddies accomplish the heat and salt transport necessary to insure that the subsurface flow is adiabatic, compensating for the heat and salt transport effected by the mean currents. The EBC thus generated occurs on a cross-shore scale of order 20-100 km, and thus this scale needs to be resolved in climate models in order to capture the meridional transport by the EBC. Our result indicate that changes in the near shore currents on the oceanic eastern boundaries are linked not just to local forcing, such as coastal changes in the winds, but depend on the basin-wide circulation as well.

  16. Accelerated simulation of passive tracers in ocean circulation models

    E-Print Network [OSTI]

    Khatiwala, Samar

    to be particularly powerful tools when combined with ocean general circulation models (GCMs). (See England and Maier's circulation, such as the poleward transport of heat, water mass transfor- mation and ventilation

  17. Sustainability in Ocean Freight Richard Cox, Branch Manager

    E-Print Network [OSTI]

    Minnesota, University of

    ­ Kuehne + Nagel New Presentation Format June 2007 p. 6 Sustainability - Scope of Certification Door compliance with ISO 9001 Quality and ISO 14001 Environmental Standards #12;16/12/2010Corporate Communications

  18. 21st century change in ocean response to climate forcing

    E-Print Network [OSTI]

    Mar?elja, Stjepan

    2015-01-01

    Modeling globally averaged information on climate forcing from the land surface temperature data, the sea surface temperatures (SST) and the empirically determined relationship between the changes in SST and the turbulent diffusion of heat into the upper ocean demonstrates a consistent link. The modeling is accurate throughout the 20th century despite the different phases of the Interdecadal Pacific Oscillation (IPO) or the strong divergence between land and ocean surface warming. It only fails during the last 15 years when SST drops well below the trend. The finding reinforces the view that slower global warming over the previous 15 years is not a caused by a negative phase of the IPO or by the variations in the upper ocean (top 700 m) warming but results from a change in the ocean behavior leading to increased heat transfer into the deeper ocean.

  19. Multi-Scale Coupling in Ocean and Climate Modeling

    SciTech Connect (OSTI)

    Zhengyu Liu, Leslie Smith

    2009-08-14

    We have made significant progress on several projects aimed at understanding multi-scale dynamics in geophysical flows. Large-scale flows in the atmosphere and ocean are influenced by stable density stratification and rotation. The presence of stratification and rotation has important consequences through (i) the conservation of potential vorticity q = {omega} {center_dot} {del} {rho}, where {omega} is the total vorticity and {rho} is the density, and (ii) the existence of waves that affect the redistribution of energy from a given disturbance to the flow. Our research is centered on quantifying the effects of potential vorticity conservation and of wave interactions for the coupling of disparate time and space scales in the oceans and the atmosphere. Ultimately we expect the work to help improve predictive capabilities of atmosphere, ocean and climate modelers. The main findings of our research projects are described.

  20. Carbon, sulfur, and phosphorus relations in oceanic Neogene sediments 

    E-Print Network [OSTI]

    Mays, Linda Lowry

    1987-01-01

    of distinguishing paleoenvironments based on C/S ratios was also investigated. C/S ratios were found to have a previously unrecognized positive correlation with organic carbon concentration. They were frequently found to be unreliable indicators of depositional... to especially thank Saulwood Lin, Miguel Huerta-Diaz, and Takeshi Arakaki who assisted me in many ways throughout this project. vhl TABLL' Ol. CONTENTS INTRODUCTION. Page BACKGROUND. BASIS OF ENVIRONMENTAL INTERPRETATION FROM C/S RATIOS. STUDY AREA. 12...

  1. Pulsar-Wind Nebulae: Recent Progress in Observations and Theory

    E-Print Network [OSTI]

    Kargaltsev, Oleg; Lyubarsky, Yuri; Striani, Edoardo

    2015-01-01

    In this review we describe recent observational and theoretical developments in our understanding of pulsar winds and pulsar-wind nebulae (PWNe). We put special emphasis on the results from observations of well-characterized PWNe of various types (e.g., torus-jet and bowshock-tail), the most recent MHD modeling efforts, and the status of the flaring Crab PWN puzzle.

  2. Observed relationships of ozone air pollution with temperature and emissions

    E-Print Network [OSTI]

    Stehr, Jeffrey

    Observed relationships of ozone air pollution with temperature and emissions Bryan J. Bloomer,1, and R. R. Dickerson (2009), Observed relationships of ozone air pollution with temperature and emissions decreased by 43% for the time period 1995 to 2002 compared with 2003 to 2006 as a result of air pollution

  3. Neutron star cooling: theoretical aspects and observational constraints

    E-Print Network [OSTI]

    Neutron star cooling: theoretical aspects and observational constraints D.G. Yakovlev a,*, O 2003 Abstract The cooling theory of isolated neutron stars is reviewed. The main cooling regulators of supranuclear matter in neutron star interiors by confronting cooling theory with observations of isolated

  4. UAV PATH FOLLOWING FOR TARGET OBSERVATION IN WIND

    E-Print Network [OSTI]

    UAV PATH FOLLOWING FOR TARGET OBSERVATION IN WIND Rolf Rysdyk, University of Washington, Seattle guidance and syn- chronous camera angles to observe a target from an unmanned-aerial-vehicle (UAV).1 Semi- autonomous operation of UAVs for target sensing have shown that operator situational awareness can be easily

  5. Observations of Collaborative Behavior in COMPS Computer Mediated Problem Solving

    E-Print Network [OSTI]

    Luther, Ken

    Observations of Collaborative Behavior in COMPS Computer Mediated Problem Solving Jung Hee Kim.glass @valpo.edu Abstract COMPS is a web-delivered computer-mediated problem solving environment for student in the problem-solving process. These observations confirm that COMPS indeed fa- cilitates true collaborative

  6. Observed and CAM3 GCM Sea Surface Wind

    E-Print Network [OSTI]

    Zender, Charles

    Observed and CAM3 GCM Sea Surface Wind Speed Distributions: Characterization, Comparison, and Bias climatological surface wind speed probability density functions (PDFs) estimated from observations and use them to evaluate, for the first time, contemporaneous wind PDFs predicted by a GCM. The ob- servations include NASA

  7. DESIGN OF THE GREAT LAKES OBSERVING SYSTEM ENTERPRISE ARCHITECTURE

    E-Print Network [OSTI]

    DESIGN OF THE GREAT LAKES OBSERVING SYSTEM ENTERPRISE ARCHITECTURE T.J. Dekker1 , J.V. DePinto1 , S, collaborative, and consensus-based enterprise architecture design process was conducted under the direction that will achieve an integrated, comprehensive, and sustainable observing system enterprise for the Great Lakes

  8. Observation of Electroweak Single Top-Quark Production

    E-Print Network [OSTI]

    Xie, Si

    We report the observation of single top-quark production using 3.2??fb[superscript -1] of pp? collision data with ?s=1.96??TeV collected by the Collider Detector at Fermilab. The significance of the observed data is 5.0 ...

  9. Mm/submm observations of symbiotic binary stars

    E-Print Network [OSTI]

    J. Mikolajewska; R. J. Ivison; A. Omont

    2002-10-22

    We present and discuss mm/submm observations of quiescent S-type symbiotic systems, and compare them with popular models proposed to account for their radio emission. We find that the M giant mass-loss rates derived from our observations are systematically higher than those reported for single M giants.

  10. Observability of Stuck-at-Faults with Differential Power Analysis

    E-Print Network [OSTI]

    Boyer, Edmond

    ,flottes,rouzeyre}@lirmm.fr Abstract In this paper we propose an innovative method to test integrated circuits based on the use of the current consumed by the circuit during net transitions, it does not require observing primary outputs of the circuit and allows the test of hard-to-observe faults. Conversely to Iddq, this technique is not sensible

  11. WIND OBSERVATIONS OF SUPRATHERMAL ELECTRONS IN THE INTERPLANETARY MEDIUM

    E-Print Network [OSTI]

    California at Berkeley, University of

    WIND OBSERVATIONS OF SUPRATHERMAL ELECTRONS IN THE INTERPLANETARY MEDIUM R. P. LIN Space Sciences Particle Instrument on the WIND spacecraft, which provides high sensitivity electron and ion measurements from solar wind thermal plasma up to &MeV energies. These results include: (1) the observation of solar

  12. Designed for: Ocean Observing Demo: A collaboration between

    E-Print Network [OSTI]

    effective low cost ocean observing system. This system was recently developed and deployed for offshore oil. The Fetch node was deployed in 550 feet of water to measure ocean temperature and pressure, and the Tsunami Observing Initiatives Pioneer Array. The Fetch will record pressure and temperatures at this site prior

  13. Ornithology Based on Linking Bird Observations with Weather Data

    E-Print Network [OSTI]

    Hyvönen, Eero

    Ornithology Based on Linking Bird Observations with Weather Data Mikko Koho1,2 , Eero Hyv¨onen2 [12]. By combining observa- tional data with related datasets, such as weather or pollution data a use case of adding value to a bird observation dataset by related weather data and a species ontology

  14. CONVENIENCE YIELD MODEL WITH PARTIAL OBSERVATIONS AND EXPONENTIAL UTILITY

    E-Print Network [OSTI]

    Carmona, Rene

    CONVENIENCE YIELD MODEL WITH PARTIAL OBSERVATIONS AND EXPONENTIAL UTILITY REN´E CARMONA AND MICHAEL. We study the value function corresponding to utility pric- ing with exponential utility. Assuming of the full information case. convenience yield, filtering, partial observations, stochastic control, utility

  15. Beyond the Standard Model of Physics with Astronomical Observations

    E-Print Network [OSTI]

    Raul Jimenez

    2013-07-09

    There has been significant recent progress in observational cosmology. This, in turn, has provided an unprecedented picture of the early universe and its evolution. In this review I will present a (biased) view of how one can use these observational results to constraint fundamental physics and in particular physics beyond the standard model.

  16. ARM Observations Projected onto CCSM Results Projected onto

    E-Print Network [OSTI]

    Mills, Richard

    ARM Observations Projected onto ARM States CCSM Results Projected onto ARM States 1Oak Ridge to Comparing Atmospheric Radiation Measurement (ARM) Data with Global Climate Model (GCM) Results Atmospheric state contained only in model results Atmospheric states contained only in ARM observations ARM

  17. EVALUATION OF PARAMETERIZED SURFACE FLUXES WITH ARM OBSERVATIONS

    E-Print Network [OSTI]

    EVALUATION OF PARAMETERIZED SURFACE FLUXES WITH ARM OBSERVATIONS G. Liu, Y. Liu, T. Toto, M. Jensen advantage of the long-term observations of surface fluxes collected by the DOE ARM program at the Great the ARM measurements based on the EC (Eddy- Correlation) and EBBR (Energy Balance Bowen Ratio) methods

  18. First satellite observations of lower tropospheric ammonia and methanol

    E-Print Network [OSTI]

    First satellite observations of lower tropospheric ammonia and methanol Reinhard Beer,1 Mark W) and methanol (CH3OH), well above the normal background levels. This is the first time that these molecules have. Citation: Beer, R., et al. (2008), First satellite observations of lower tropospheric ammonia and methanol

  19. Scavenging quantum information: Multiple observations of quantum systems

    E-Print Network [OSTI]

    Peter Rapcan; John Calsamiglia; Ramon Munoz-Tapia; Emilio Bagan; Vladimir Buzek

    2011-05-26

    Given an unknown state of a qudit that has already been measured optimally, can one still extract any information about the original unknown state? Clearly, after a maximally informative measurement, the state of the system `collapses' into a post-measurement state from which the {\\em{same}} observer cannot obtain further information about the original state of the system. However, the system still encodes a significant amount of information about the original preparation for a second observer who is unaware of the actions of the first one. We study how a series of independent observers can obtain, or scavenge, information about the unknown state of a system (quantified by the fidelity) when they sequentially measure it. We give closed-form expressions for the estimation fidelity, when one or several qudits are available to carry information about the single-qudit state, and study the `classical' limit when an arbitrarily large number of observers can obtain (nearly) complete information on the system. In addition to the case where all observers perform most informative measurements we study the scenario where a finite number of observers estimate the state with equal fidelity,regardless of their position in the measurement sequence; and the scenario where all observers use identical measurement apparata (up to a mutually unknown orientation) chosen so that a particular observer's estimation fidelity is maximized.

  20. OBSERVATIONS OF THE EFFECT OF ACID-IRON

    E-Print Network [OSTI]

    OBSERVATIONS OF THE EFFECT OF ACID-IRON WASTE DISPOSAL AT SEA ON ANIMAL POPULATIONS tj^iitinn p AND WILDLIFE SERVICE #12;#12;OBSERVATIONS OF THE EFFECT OF ACID-IRON WASTE DISPOSAL AT SEA ON ANIMAL scope, intended to aid or direct management or utilization practices and as guides for administrative

  1. THEORY OF THE CONTROL OF OBSERVABLE QUANTUM V. P. BELAVKIN

    E-Print Network [OSTI]

    Belavkin, Viacheslav P.

    . The general problem of optimal control of a quantum-mechanical system is discussed and the corre- sponding], of the dynamical observation and feedback control optimization problems for such systems has provided a means measurement and control of classical (i.e., non-quantum) Markov processes with quantum observation channels

  2. Spatial Standard Observer for Visual Technology Andrew B. Watson

    E-Print Network [OSTI]

    , acuity, discrimination, model, modelfest, standard observer. 1 Definition The Spatial Standard Observer at a specific viewing distance, and the pixels have a known relation to luminance. The output of the metric of log contrast energy. The horizontal axis indicates ModelFest stimulus number. Miniature versions

  3. The Autonomous Observer: A Tool for Remote Experimentation in Robotics

    E-Print Network [OSTI]

    Latombe, Jean-Claude

    { the Autonomous Observer (AO) { developed to facilitate experimentation over the Internet. The AO is a mobile the target's pose. This pose is sent over the Internet to remote users who can observe 3-D real-time graphic de Estudios Superiores de Monterrey (ITESM) in Mexico. The goal of this project was to develop

  4. First Epoch Observations of 3-Helium with the

    E-Print Network [OSTI]

    Balser, Dana S.

    First Epoch Observations of 3-Helium with the Green Bank Telescope THOMAS M. BANIA Institute #12;3-Helium Experiment Status GBT now fully operational for 3-He First GBT 3-He epoch complete-He detection for the PN J320 (see Balser et al. poster) NAIC Arecibo Observatory 305 m observations

  5. ISSN 18458319 COMMON SPHINX AND RHESSI OBSERVATIONS OF

    E-Print Network [OSTI]

    Mrozek, Tomasz

    V energy resolution. SphinX data overlap with the low-energy end of the Ramaty High Energy Solar. Observational Data The Reuven Ramaty High Energy Solar Spectroscopic Imager (RHESSI) is a rotating FourierISSN 1845­8319 COMMON SPHINX AND RHESSI OBSERVATIONS OF SOLAR FLARES T. MROZEK1,2 , S. GBUREK1 , M

  6. Numerical models of the geodynamo and observational constraints

    E-Print Network [OSTI]

    Dormy, Emmanuel

    , and paleomagnetic observations have been interpreted as actual geomagnetic features and used as constraints. Keywords: Geodynamo; Earth core; geomagnetic field; magnetic records. Index terms: Dynamo theory; time much more recently. Papers coauthored by dynamo specialists and geophysicists observing the field over

  7. Measuring Transactions Costs from Observed Behavior: Market Choices in Peru

    E-Print Network [OSTI]

    Sadoulet, Elisabeth

    Measuring Transactions Costs from Observed Behavior: Market Choices in Peru Renos Vakis, Elisabeth Sadoulet, and Alain de Janvry October 2003 Abstract Farmers incur proportional and fixed transactions costs these transactions costs. When opportunities exist to sell a crop on alternative markets, the observed choice

  8. Synoptic Observing Programs at Big Bear Solar Observatory

    E-Print Network [OSTI]

    Synoptic Observing Programs at Big Bear Solar Observatory Haimin Wang and Philip R. Goode Big Bear and en- hance the comprehensive synoptic observing programs at BBSO, which include the following ve studies. Statistical studies on sunspot areas and magnetic shear are among the highlights of this research

  9. Seismic Observation Systems in Nagoya University and Publication of Data

    E-Print Network [OSTI]

    Southern California, University of

    Seismic Observation Systems in Nagoya University and Publication of Data Nobuo Fukuwa,a) Jun Tobita,b) and Hiroaki Kojimac) This paper reports the current situation of the seismic monitoring program conducted by Nagoya University. First, the system for observing seismic ground motion in the Tokai Region is described

  10. Astrophysical jets: Observations, numerical simulations, and laboratory experiments

    E-Print Network [OSTI]

    Bellan, Paul M.

    Astrophysical jets: Observations, numerical simulations, and laboratory experiments P. M. Bellan,1; published online 22 April 2009 This paper provides summaries of ten talks on astrophysical jets given of observation, numerical modeling, and laboratory experiment. One essential feature of jets, namely

  11. NS&T Management Observations - 3rd Quarter

    SciTech Connect (OSTI)

    David Gianotto

    2014-07-01

    The INL Management Observation Program (MOP) is designed to improve managers and supervisors understanding of work being performed by employees and the barriers impacting their success. The MOP also increases workers understanding of managements’ expectations as they relate to safety, security, quality, and work performance. Management observations are designed to improve the relationship and trust between employees and managers through increased engagement and interactions between managers and researchers in the field. As part of continuous improvement, NS&T management took initiative to focus on the participation and quality of observations in FY 14. This quarterly report is intended to (a) summarize the participation and quality of management’s observations, (b) assess observations for commonalities or trends related to facility or process barriers impacting research, and (c) provide feedback and make recommendations for improvements NS&T’s MOP.

  12. Galactic mapping with general relativity and the observed rotation curves

    E-Print Network [OSTI]

    Magalhaes, Nadja S

    2015-01-01

    Typically, stars in galaxies have higher velocities than predicted by Newtonian gravity in conjunction with observable galactic matter. To account for the phenomenon, some researchers modified Newtonian gravitation; others introduced dark matter in the context of Newtonian gravity. We employed general relativity successfully to describe the galactic velocity profiles of four galaxies: NGC 2403, NGC 2903, NGC 5055 and the Milky Way. Here we map the density contours of the galaxies, achieving good concordance with observational data. In our Solar neighbourhood, we found a mass density and density fall-off fitting observational data satisfactorily. From our GR results, using the threshold density related to the observed optical zone of a galaxy, we had found that the Milky Way was indicated to be considerably larger than had been believed to be the case. To our knowledge, this was the only such existing theoretical prediction ever presented. Very recent observational results by Xu et al. have confirmed our predi...

  13. Objectivity of Quantum Measurement in Many-Observer World

    E-Print Network [OSTI]

    Sheng-Wen Li; C. Y. Cai; X. F. Liu; C. P. Sun

    2015-08-06

    The objectivity of quantum measurement is treated as an emergent phenomenon with $N$ observers who can agree to the same result of measurement, and meanwhile, they can identify their records with each other. In this many-observer world (MOW), an objective quantum measurement is dealt with as a multipartite [$(N+1)$-body] quantum correlation among the measured system and $N$ observers when its bipartite reductions are the same classical correlations. With this conceptual clarification, we find that, an objective quantum measurement is implemented if and only if the MOW is initially factorized in a pure state and then the total system can evolve into a generalized GHZ state with respect to the orthogonal basis preferred by each observer. Especially, such objective quantum measurement is recast in ideal classical correlation when the observer world is macroscopic for $N\\rightarrow\\infty$.

  14. 15th Symposium on Meteorological Observations and Instrumentation, AMS, Atlanta, 2010 RECENT RESEARCH ON METEOROLOGICAL OBSERVATIONS AND INSTRUMENTATION AT

    E-Print Network [OSTI]

    Wauben, Wiel

    15th Symposium on Meteorological Observations and Instrumentation, AMS, Atlanta, 2010 1 RECENT RESEARCH ON METEOROLOGICAL OBSERVATIONS AND INSTRUMENTATION AT KNMI Hannelore Bloemink, Marijn de Haij are generated at about 30 locations in the meteorological network and are centrally available every 10 minutes

  15. Behaviour Observation in Software Testing 20/08/99 A Theory of Behaviour Observation in Software Testing

    E-Print Network [OSTI]

    Zhu, Hong

    Behaviour Observation in Software Testing 20/08/99 -- 1 -- A Theory of Behaviour Observation in Software Testing Hong Zhu School of Computing and Mathematics, Oxford Brookes University, Gipsy Lane International University, University Park, Miami, FL 33199, Email: hex@cs.fiu.edu Abstract Software testing

  16. Observation of interference between two Bose condensates The spatial coherence of a Bose condensate was demonstrated by observing

    E-Print Network [OSTI]

    Observation of interference between two Bose condensates The spatial coherence of a Bose condensate was demonstrated by observing interference between two Bose condensates [1]. They were created by cooling atoms the condensates expand for 40 milliseconds and overlap (see figure). This demonstrates that Bose condensed atoms

  17. Smearing of Observables and Spectral Measures on Quantum Structures

    E-Print Network [OSTI]

    Anatolij Dvure?enskij

    2012-04-29

    An observable on a quantum structure is any $\\sigma$-homomorphism of quantum structures from the Borel $\\sigma$-algebra of the real line into the quantum structure which is in our case a monotone $\\sigma$-complete effect algebras with the Riesz Decomposition Property. We show that every observable is a smearing of a sharp observable which takes values from a Boolean $\\sigma$-subalgebra of the effect algebra, and we prove that for every element of the effect algebra there is its spectral measure.

  18. World-line observables and clocks in General Relativity

    E-Print Network [OSTI]

    Hossein Farajollahi

    2005-11-20

    A proposal for the issue of time and observables in any parameterized theory such as general relativity is addressed. Introduction of a gauge potential 3-form A in the theory of relativity enables us to define a gauge-invariant quantity which can be used by observers as a clock to measure the passage of time. This dynamical variable increases monotonically and continuously along a world line. Then we define world line observables to be any covariantly defined quantity obtained from the field configurations on any such causal past with dynamical time T.

  19. Polarization Observables in the Photoproduction of Two Pseudoscalar Mesons

    SciTech Connect (OSTI)

    Winston Roberts

    2005-10-12

    The many polarization observables that can be measured in process like {gamma}N {yields} M{sub 1}M{sub 2}B, where M{sub 1} and M{sub 2} are pseudoscalar mesons and B is a spin-1/2 baryon, are discussed. The relationships among these observables, their symmetries, as well as inequalities that they satisfy are briefly discussed. Within the context of a particular model for {gamma}N {yields} NKK, some of the observables are calculated, and their sensitivity to the ingredients of the model, and hence to the underlying dynamics of the process, are discussed.

  20. Observer-dependent optical properties of stationary axisymmetric spacetimes

    E-Print Network [OSTI]

    Donato Bini; Fernando de Felice; Andrea Geralico

    2014-08-23

    The world lines of null particles admit arbitrary parametrizations. In the presence of a family of observers one may introduce along a null world line an extension of the so-called Cattaneo's relative standard time parameter (valid for massive particles) which plays a special role. Another possibility is to use the coordinate time itself as a parameter. The relation between relative standard time and coordinate time allows for the introduction of an observer-dependent optical path and associated refraction index. Both these quantities are studied here working out explicit examples concerning familiar null orbits and observers in black hole spacetimes.

  1. Identification of Observables for Quark and Gluon Orbital Angular Momentum

    E-Print Network [OSTI]

    Courtoy, Aurore; Hernandez, J Osvaldo Gonzalez; Liuti, Simonetta; Rajan, Abha

    2014-01-01

    A new debate has recently arisen on the subject of orbital angular momentum in QCD, in particular on its observability and on its partonic interpretation. Orbital momentum can be defined in QCD using two different decomposition schemes that yield a kinetic and a canonical definition, respectively. We argue that kinetic orbital angular momentum is intrinsically associated with twist three generalized parton distributions, and it is therefore more readily observable, while, due to parity constraints, canonical angular momentum, if defined as suggested in the literature in terms of generalized transverse momentum distributions, cannot be observed in scattering processes involving a single hadronic reaction plane.

  2. Identification of Observables for Quark and Gluon Orbital Angular Momentum

    E-Print Network [OSTI]

    Aurore Courtoy; Gary R. Goldstein; J. Osvaldo Gonzalez Hernandez; Simonetta Liuti; Abha Rajan

    2014-12-01

    A new debate has recently arisen on the subject of orbital angular momentum in QCD, in particular on its observability and on its partonic interpretation. Orbital momentum can be defined in QCD using two different decomposition schemes that yield a kinetic and a canonical definition, respectively. We argue that kinetic orbital angular momentum is intrinsically associated with twist three generalized parton distributions, and it is therefore more readily observable, while, due to parity constraints, canonical angular momentum, if defined as suggested in the literature in terms of generalized transverse momentum distributions, cannot be observed in scattering processes involving a single hadronic reaction plane.

  3. Chandra Orion Ultradeep Project: Observations and Source Lists

    E-Print Network [OSTI]

    Getman, K V; Broos, P S; Grosso, N; Tsujimoto, M; Townsley, L K; Garmire, G P; Kästner, J H; Li, J; Harnden, F R; Wolk, S; Murray, S S; Lada, C J; Münch, A; McCaughrean, M J; Meeus, G; Damiani, F; Micela, G; Sciortino, S; Bally, J; Hillenbrand, L A; Herbst, W; Preibisch, T; Feigelson, E D

    2004-01-01

    We present a description of the data reduction methods and the derived catalog of more than 1600 X-ray point sources from the exceptionally deep January 2003 Chandra X-ray Observatory observation of the Orion Nebula Cluster and embedded populations around OMC-1. The observation was obtained with Chandra's Advanced CCD Imaging Spectrometer (ACIS) and has been nicknamed the Chandra Orion Ultradeep Project (COUP). With an 838 ks exposure made over a continuous period of 13.2 days, the COUP observation provides the most uniform and comprehensive dataset on the X-ray emission of normal stars ever obtained in the history of X-ray astronomy.

  4. Chandra Orion Ultradeep Project: Observations and Source Lists

    E-Print Network [OSTI]

    K. V. Getman; E. Flaccomio; P. S. Broos; N. Grosso; M. Tsujimoto; L. Townsley; G. P. Garmire; J. Kastner; J. Li; F. R. Harnden, Jr.; S. Wolk; S. S. Murray; C. J. Lada; A. A. Muench; M. J. McCaughrean; G. Meeus; F. Damiani; G. Micela; S. Sciortino; J. Bally; L. A. Hillenbrand; W. Herbst; T. Preibisch; E. D. Feigelson

    2004-10-06

    We present a description of the data reduction methods and the derived catalog of more than 1600 X-ray point sources from the exceptionally deep January 2003 Chandra X-ray Observatory observation of the Orion Nebula Cluster and embedded populations around OMC-1. The observation was obtained with Chandra's Advanced CCD Imaging Spectrometer (ACIS) and has been nicknamed the Chandra Orion Ultradeep Project (COUP). With an 838 ks exposure made over a continuous period of 13.2 days, the COUP observation provides the most uniform and comprehensive dataset on the X-ray emission of normal stars ever obtained in the history of X-ray astronomy.

  5. Classification of Energy Flow Observables in Narrow Jets

    E-Print Network [OSTI]

    Guy Gur-Ari; Michele Papucci; Gilad Perez

    2011-01-14

    We present a classification of energy flow variables for highly collimated jets. Observables are constructed by taking moments of the energy flow and forming scalars of a suitable Lorentz subgroup. The jet shapes are naturally arranged in an expansion in both angular and energy resolution, allowing us to derive the natural observables for describing an N-particle jet. We classify the leading variables that characterize jets with up to 4 particles. We rediscover the familiar jet mass, angularities, and planar flow, which dominate the lowest order substructure variables. We also discover several new observables and we briefly discuss their physical interpretation.

  6. CX-011436: Categorical Exclusion Determination

    Broader source: Energy.gov [DOE]

    Development of Methods to Prohibit and Remediate Loss of Annular Isolation in Shale Gas Wells CX(s) Applied: A9, A11, Specific Category: field observation of drilling operations Date: 11/21/2013 Location(s): Arkansas Offices(s): National Energy Technology Laboratory

  7. CX-012686: Categorical Exclusion Determination

    Broader source: Energy.gov [DOE]

    An Investigation To Establish Multiphysical Property Dataset of Nuclear Materials Based on In- Situ Observations and Measurements, NEAMS: Nuclear Energy Advanced Modeling and Simulation – Purdue University CX(s) Applied: B3.6Date: 41862 Location(s): IndianaOffices(s): Nuclear Energy

  8. CX-012702: Categorical Exclusion Determination

    Broader source: Energy.gov [DOE]

    An Investigation To Establish Multiphysical Property Dataset of Nuclear Materials Based on In-Situ Observations and Measurements, NEAMS: Nuclear Energy Advanced Modeling and Simulation – Purdue University CX(s) Applied: B3.6Date: 41862 Location(s): IndianaOffices(s): Nuclear Energy

  9. 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...

  10. GALEX DIFFUSE OBSERVATIONS OF THE SKY: THE DATA

    SciTech Connect (OSTI)

    Murthy, Jayant

    2014-08-01

    I present tabulations of the diffuse observations made by the GALEX spacecraft in two UV bands (FUV: 1539 Å and NUV: 2316 Å) from the (almost) final data release of the GALEX spacecraft (GR6/GR7). This data release includes all the FUV observations and the majority of the NUV observations. I discuss overall trends in the data but the primary purpose of this paper is to make the data available to the public. The data files described in this paper are hosted by the Mikulski Archive for Space Telescopes at the Space Telescope Science Insitute from whence they may be downloaded. For ease of use, I have also created maps of the diffuse radiation in both bands over the entire observed sky at 6' resolution.

  11. Review of Structures in the Energy Dependence of Hadronic Observables

    E-Print Network [OSTI]

    C. Blume

    2006-11-02

    The energy dependence of various hadronic observables is reviewed. The study of their evolution from AGS over SPS to the highest RHIC energy reveals interesting features, which might locate a possible onset of deconfinement. These observables include transverse spectra of different particle types and their total multiplicities, as well as elliptic flow. In this context especially the observation of a maximum of the strangeness to pion ratio is of particular interest, since on one hand it has been predicted as a signal for the onset of deconfinement but on the other hand also statistical model calculations exhibit qualitatively similar structures. The sharpness of these features is however not reproduced by hadronic scenarios. The significance of these structures will be discussed in this contribution. Other observables, such as radius parameters from Bose-Einstein correlations, on the other hand do not exhibit any structure in their energy dependence.

  12. Core Lithology State of Hawail Scientific Observation Hole 2...

    Open Energy Info (EERE)

    Core Lithology State of Hawail Scientific Observation Hole 2 Kilauea Volcano, Hawaii Jump to: navigation, search OpenEI Reference LibraryAdd to library Report: Core Lithology State...

  13. Core Lithology State of Hawaii Scientific Observation Hole 4...

    Open Energy Info (EERE)

    Core Lithology State of Hawaii Scientific Observation Hole 4 Kilauea Volcano, Hawaii Jump to: navigation, search OpenEI Reference LibraryAdd to library Report: Core Lithology State...

  14. Core Lithology From the State of Hawaii Scientific Observation...

    Open Energy Info (EERE)

    Core Lithology From the State of Hawaii Scientific Observation Hole 1, Kilauea Volcano, Hawaii Jump to: navigation, search OpenEI Reference LibraryAdd to library Report: Core...

  15. Real time observations of the nucleation and growth of nanowires...

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

    Real time observations of the nucleation and growth of nanowires and nanotubes December 1, 2011 at 3pm36-428 Eric Stach Center for Functional Nanomaterials, Brookhaven National...

  16. Observation of New Charmless Decays of Bottom Hadrons

    E-Print Network [OSTI]

    Xie, Si

    We search for new charmless decays of neutral b hadrons to pairs of charged hadrons, using 1??fb[superscript -1] of data collected by the CDF II detector at the Fermilab Tevatron. We report the first observation of the ...

  17. Atomic-Scale Observations Aid Mesoscale Catalyst Design | ornl...

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

    Materials Characterization Atomic-Scale Observations Aid Mesoscale Catalyst Design April 08, 2015 Fig.1. Z-contrast STEM image shows the Mo-V-Te-Ta oxide catalyst. (a) "M1-like"...

  18. Press Pass - Press Release - DZero ZZ diboson observation

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

    of the ZZ diboson make its discovery an essential prelude to finding or excluding the Higgs boson at the Tevatron. The observation of the ZZ, announced at a Fermilab seminar on...

  19. Observer-based fault detection for nuclear reactors

    E-Print Network [OSTI]

    Li, Qing, 1972-

    2001-01-01

    This is a study of fault detection for nuclear reactor systems. Basic concepts are derived from fundamental theories on system observers. Different types of fault- actuator fault, sensor fault, and system dynamics fault ...

  20. Short communication Observations of eruptive activity at Santiaguito volcano, Guatemala

    E-Print Network [OSTI]

    Rose, William I.

    Short communication Observations of eruptive activity at Santiaguito volcano, Guatemala Gregg J volcano, Guatemala, from the vantage point of its parent, Santa Mari´a. We have taken 12 h of digital

  1. Observation of interference fringes in Autler-Townes line shapes 

    E-Print Network [OSTI]

    Wilkinson, S. R.; Smith, A. V.; Scully, Marlan O.; Fry, Edward

    1996-01-01

    We observe Ramsey fringes in the absorption line shape for a weak optical field probing the transition between an unperturbed quantum state and one that is dynamically Stark shifted by a strong pump field....

  2. A multisensory observer model for human spatial orientation perception

    E-Print Network [OSTI]

    Newman, Michael C. (Michael Charles)

    2009-01-01

    Quantitative "observer" models for spatial orientation and eye movements have been developed based on 1-G data from humans and animals (e.g. Oman 1982, 1991, Merfeld, et al 1993, 2002; Haslwanter 2000, Vingerhoets 2006). ...

  3. Observable signatures of general relativistic dynamics in compact binaries

    E-Print Network [OSTI]

    Lang, Ryan N. (Ryan Nathan)

    2009-01-01

    The effects of general relativity (GR) in astrophysical systems are often difficult to calculate, but they can have important consequences for observables. This thesis considers the impact of previously-ignored GR effects ...

  4. Observation of Magnetoelectric Multiferroicity in a Cubic Perovskite...

    Office of Scientific and Technical Information (OSTI)

    Observation of Magnetoelectric Multiferroicity in a Cubic Perovskite System:LaMn3Cr4O12 Citation Details In-Document Search This content will become publicly available on August...

  5. ALMA Observations of the Sun in Cycle 4 and Beyond

    E-Print Network [OSTI]

    Wedemeyer, S; Battaglia, M; Labrosse, N; Fleishman, G; Hudson, H; Antolin, P; Alissandrakis, C; Ayres, T; Ballester, J; Bastian, T; Black, J; Benz, A; Brajsa, R; Carlsson, M; Costa, J; DePontieu, B; Doyle, G; de Castro, G Gimenez; Gunár, S; Harper, G; Jafarzadeh, S; Loukitcheva, M; Nakariakov, V; Oliver, R; Schmieder, B; Selhorst, C; Shimojo, M; Simões, P; Soler, R; Temmer, M; Tiwari, S; Van Doorsselaere, T; Veronig, A; White, S; Yagoubov, P; Zaqarashvili, T

    2016-01-01

    This document was created by the Solar Simulations for the Atacama Large Millimeter Observatory Network (SSALMON) in preparation of the first regular observations of the Sun with the Atacama Large Millimeter/submillimeter Array (ALMA), which are anticipated to start in ALMA Cycle 4 in October 2016. The science cases presented here demonstrate that a large number of scientifically highly interesting observations could be made already with the still limited solar observing modes foreseen for Cycle 4 and that ALMA has the potential to make important contributions to answering long-standing scientific questions in solar physics. With the proposal deadline for ALMA Cycle 4 in April 2016 and the Commissioning and Science Verification campaign in December 2015 in sight, several of the SSALMON Expert Teams composed strategic documents in which they outlined potential solar observations that could be feasible given the anticipated technical capabilities in Cycle 4. These documents have been combined and supplemented w...

  6. Observations of Gamma-Ray Bursts at Extreme Energies

    E-Print Network [OSTI]

    Aune, Taylor

    2012-01-01

    of Gamma-Ray Bursts . . . . . . . . . . . . . Redshift-Ancient Unvierse with Gamma-Ray Bursts, pages 330–333. AIP,A. Olson. Observations of Gamma-Ray Bursts of Cosmic Origin.

  7. Ab initio estimates of the size of the observable universe

    SciTech Connect (OSTI)

    Page, Don N., E-mail: profdonpage@gmail.com [Department of Physics, 4-183 CCIS, University of Alberta, Edmonton, Alberta T6G 2E1 Canada (Canada)

    2011-09-01

    When one combines multiverse predictions by Bousso, Hall, and Nomura for the observed age and size of the universe in terms of the proton and electron charge and masses with anthropic predictions of Carter, Carr, and Rees for these masses in terms of the charge, one gets that the age of the universe should be roughly the inverse 64th power, and the cosmological constant should be around the 128th power, of the proton charge. Combining these with a further renormalization group argument gives a single approximate equation for the proton charge, with no continuous adjustable or observed parameters, and with a solution that is within 8% of the observed value. Using this solution gives large logarithms for the age and size of the universe and for the cosmological constant that agree with the observed values within 17%.

  8. Navigation System for Ground Vehicles using Temporally Interconnected Observers

    E-Print Network [OSTI]

    navigation technique for an automotive vehicle. This method involves several observers, each designed attitude measurements from an inertial measurement unit (IMU) is performed (at rest) on the launch platform

  9. Search for Large Extra Dimensions Based on Observations of Neutron...

    Office of Scientific and Technical Information (OSTI)

    ThesisDissertation: Search for Large Extra Dimensions Based on Observations of Neutron Stars with the Fermi-LAT Citation Details In-Document Search Title: Search for Large Extra...

  10. Observation of suppressed terahertz absorption in photoexcited graphene

    E-Print Network [OSTI]

    Frenzel, Alex James

    When light is absorbed by a semiconductor, photoexcited charge carriers enhance the absorption of far-infrared radiation due to intraband transitions. We observe the opposite behavior in monolayer graphene, a zero-gap ...

  11. Democracy and the Performance of Power: Observations from Nigeria

    E-Print Network [OSTI]

    Ochonu, Moses

    2005-01-01

    Confession," The G11ardia11 (Nigeria) June 11. Foucault,2002. "Abuse of Democracy," ThisDay (Nigeria) Nov. 26, 2001.Power: Observations from Nigeria Moses Ochonu Abstract Since

  12. Preprint, 9th Symposium on Integrated Observing and Assimilation Systems

    E-Print Network [OSTI]

    Droegemeier, Kelvin K.

    innovative observing systems for high- resolution sensing of the lower atmosphere. The devel- opment of low-cost with polarimetric capabilities is one of the first goals. Such networks are to probe the lower atmos- phere

  13. New Observation on Division Property Bing Sun1,a

    E-Print Network [OSTI]

    International Association for Cryptologic Research (IACR)

    New Observation on Division Property Bing Sun1,a , Xin Hai1,b , Wenyu Zhang2,c , Lei Cheng1,d Sun et al. With these notations, we can determine that, after applying a bijective trans- formation

  14. Integrating spacecraft and aircraft in Earth Observation System architectures

    E-Print Network [OSTI]

    Suarez, Brandon H

    2011-01-01

    The Global Earth Observation System (GEOS) is the essential data gathering network that enables the advancement of Earth science. In recent years, efforts have been made to understand the major GEOS architectural tradeoffs. ...

  15. Symmetry-Breaking Orbital Anisotropy Observed for Detwinned Ba...

    Office of Scientific and Technical Information (OSTI)

    Observed for Detwinned Ba(Fe (1-X) Co (X) ) (2) As (2) Above the Spin Density Wave Transition Citation Details In-Document Search Title: Symmetry-Breaking Orbital...

  16. Direct Observation of the Oxygenated Species during Oxygen Reduction...

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

    Direct Observation of the Oxygenated Species during Oxygen Reduction on a Platinum Fuel Cell Cathode Friday, December 20, 2013 Fuel Cell Figure 1 Figure 1. In situ x-ray...

  17. OBSERVATIONS ON JUVENILE OCEANIC SKIPJACK (KATSUWONUS PELAMIS) FROM

    E-Print Network [OSTI]

    OBSERVATIONS ON JUVENILE OCEANIC SKIPJACK (KATSUWONUS PELAMIS) FROM HAWAIIAN WATERS AND SIERRA SKIPJACK (KATSUWONUS PELAMIS) FROM HAWAIIAN WATERS AND SIERRA MACKEREL (SCOMBEROMORUS SIERRA) FROM September 1948. While operating in Hawaiian waters, seven juvenile KatsllwollllS pelamis (Linnaeus) 1758

  18. MACHO Mass Determination Based on Space Telescope Observation

    E-Print Network [OSTI]

    Mareki Honma

    1999-03-24

    We investigate the possibility of lens mass determination for a caustic crossing microlensing event based on a space telescope observation. We demonstrate that the parallax due to the orbital motion of a space telescope causes a periodic fluctuation of the light curve, from which the lens distance can be derived. Since the proper motion of the lens relative to the source is also measurable for a caustic crossing event, one can find a full solution for microlensing properties of the event, including the lens mass. To determine the lens mass with sufficient accuracy, the light curve near the caustic crossing should be observed within uncertainty of $\\sim$ 1%. We argue that the Hubble Space Telescope observation of the caustic crossing supplied with ground-based observations of the full light curve will enable us to determine the mass of MACHOs, which is crucial for understanding the nature of MACHOs.

  19. Observation of the ?[subscript b][superscript 0] Baryon

    E-Print Network [OSTI]

    Bauer, Gerry P.

    The observation of the bottom, strange baryon ?[subscript b][superscript 0] through the decay chain ?[subscript b][superscript 0]??[subscript c][superscript +]?[superscript -], where ?[subscript c][superscript +]??[superscript ...

  20. Observation of Entanglement-Dependent Two-Particle Holonomic Phase

    E-Print Network [OSTI]

    J. C. Loredo; M. A. Broome; D. H. Smith; A. G. White

    2015-06-18

    Holonomic phases---geometric and topological---have long been an intriguing aspect of physics. They are ubiquitous, ranging from observations in particle physics to applications in fault tolerant quantum computing. However, their exploration in particles sharing genuine quantum correlations lack in observations. Here we experimentally demonstrate the holonomic phase of two entangled-photons evolving locally, which nevertheless gives rise to an entanglement-dependent phase. We observe its transition from geometric to topological as the entanglement between the particles is tuned from zero to maximal, and find this phase to behave more resilient to evolution changes with increasing entanglement. Furthermore, we theoretically show that holonomic phases can directly quantify the amount of quantum correlations between the two particles. Our results open up a new avenue for observations of holonomic phenomena in multi-particle entangled quantum systems.

  1. Gaussian Observation Hidden Markov models for EEG analysis

    E-Print Network [OSTI]

    Penny, Will

    Gaussian Observation Hidden Markov models for EEG analysis William D. Penny and Stephen J. Roberts, Imperial College of Science, Technology and Medicine, London SW7 2BT., U.K. w.penny@ic.ac.uk, s

  2. Probing the Sun with ALMA: observations and simulations

    E-Print Network [OSTI]

    Loukitcheva, Maria; White, Stephen M; Carlsson, Mats

    2015-01-01

    ALMA will open a new chapter in the study of the Sun by providing a leap in spatial resolution and sensitivity compared to currently available mm wave- length observations. In preparation of ALMA, we have carried out a large number of observational tests and state-of-the-art radiation MHD simulations. Here we review the best available observations of the Sun at millimeter wavelengths.Using state of the art radiation MHD simulations of the solar atmosphere we demonstrate the huge potential of ALMA observations for uncovering the nature of the solar chromosphere. We show that ALMA will not only provide a reliable probe of the thermal structure and dynamics of the chromosphere, it will also open up a powerful new diagnostic of magnetic field at chromospheric heights, a fundamentally important, but so far poorly known parameter.

  3. ITEP Webinar: About the Local Environmental Observer (LEO) Network

    Broader source: Energy.gov [DOE]

    Attend this Institute for Tribal Environmental Professionals (ITEP) webinar and learn how the Local Environmental Observer (LEO) Network provides a model for engaging communities; connecting with technical experts and resources; and disseminating information about specific events and the impacts, needs, and responses. This webinar will introduce LEO as a resource comprised of local experts who collect observations about unusual environmental events and serve as the eyes, ears and voice of environmental change in their communities.

  4. Agriculture, Free Trade, and Global Development: Some Personal Observations

    E-Print Network [OSTI]

    Head, John W.

    2005-01-01

    Agriculture, Free Trade, and Global Development: Some Personal Observations John W. Head* I am very pleased to have been invited to offer some luncheon remarks for the Law School's Symposium on Agriculture, Free Trade, and Global Development. My..., or at least a light break from the weighty papers being presented at the symposium, if I were to offer some of my own personal observations about the three subject areas that combine to give this symposium its title: agriculture, free trade, and global...

  5. Initial Observations of Sunspot Oscillations Excited by Solar Flare

    E-Print Network [OSTI]

    A. G. Kosovichev; T. Sekii

    2007-10-09

    Observations of a large solar flare of December 13, 2006, using Solar Optical Telescope (SOT) on Hinode spacecraft revealed high-frequency oscillations excited by the flare in the sunspot chromosphere. These oscillations are observed in the region of strong magnetic field of the sunspot umbra, and may provide a new diagnostic tool for probing the structure of sunspots and understanding physical processes in solar flares.

  6. Hydrogen geocorona: simultaneous optical and radar observations at Arecibo

    SciTech Connect (OSTI)

    Kerr, R.B.

    1986-01-01

    Observations of the geocoronal H/sub ..cap alpha../ emission with a high resolution Fabry-Perot interferometer were made simultaneously with observations of the topside F region using the incoherent scatter radar at Arecibo, for the purpose of monitoring the exobase temperature and the hydrogen velocity distribution over half of a solar cycle. The variation of H density with solar activity agrees with that of previous observations. These observations have shown that the charge exchange reaction of H with H/sup +/ perturbs the ballistic hydrogen velocity distribution above the exobase in the fall and winter months at Arecibo. The exobase temperature is hotter than would be expected for winter solar minimum conditions due to a drop of the protonosphere base during these periods. A multi-constituent analysis of the radar data places the base of the protonosphere near 550 km in the early morning hours of the late fall and early winter. A maximum in downward ion velocities is also observed during these times. For observations near the neutral equinox, the charge exchange reaction does not significantly perturb the neutral hydrogen velocity distribution.

  7. Multi-wavelength Observations of H 2356-309

    E-Print Network [OSTI]

    Abramowski, A; Aharonian, F; Akhperjanian, A G; Anton, G; de Almeida, U Barres; Bazer-Bachi, A R; Becherini, Y; Behera, B; Benbow, W; Bernloehr, K; Bochow, A; Boisson, C; Bolmont, J; Borrel, V; Brucker, J; Brun, F; Brun, P; Buehler, R; Bulik, T; Buesching, I; Boutelier, T; Chadwick, P M; Charbonnier, A; Chaves, R C G; Cheesebrough, A; Conrad, J; Chounet, L -M; Clapson, A C; Coignet, G; Costamante, L; Dalton, M; Daniel, M K; Davids, I D; Degrange, B; Deil, C; Dickinson, H J; Djannati-Atai, A; Domainko, W; Drury, L O'C; Dubois, F; Dubus, G; Dyks, J; Dyrda, M; Egberts, K; Eger, P; Espigat, P; Fallon, L; Farnier, C; Fegan, S; Feinstein, F; Fernandes, M V; Fiasson, A; Foerster, A; Fontaine, G; Fuessling, M; Gabici, S; Gallant, Y A; Gerard, L; Gerbig, D; Giebels, B; Glicenstein, J F; Glueck, B; Goret, P; Goering, D; Hampf, D; Hauser, M; Heinz, S; Heinzelmann, G; Henri, G; Hermann, G; Hinton, J A; Hoffmann, A; Hofmann, W; Hofverberg, P; Holleran, M; Hoppe, S; Horns, D; Jacholkowska, A; de Jager, O C; Jahn, C; Jung, I; Katarzynski, K; Katz, U; Kaufmann, S; Kerschhaggl, M; Khangulyan, D; Khelifi, B; Keogh, D; Klochkov, D; Kluzniak, W; Kneiske, T; Komin, Nu; Kosack, K; Kossakowski, R; Lamanna, G; Lenain, J -P; Lohse, T; Lu, C -C; Marandon, V; Marcowith, A; Masbou, J; Maurin, D; McComb, T J L; Medina, M C; Mehault, J; Moderski, R; Moulin, E; Naumann-Godo, M; de Naurois, M; Nedbal, D; Nekrassov, D; Nguyen, N; Nicholas, B; Niemiec, J; Nolan, S J; Ohm, S; Olive, J-F; Wilhelmi, E de Ona; Opitz, B; Orford, K J; Ostrowski, M; Panter, M; Arribas, M Paz; Pedaletti, G; Pelletier, G; Petrucci, P -O; Pita, S; Puehlhofer, G; Punch, M; Quirrenbach, A; Raubenheimer, B C; Raue, M; Rayner, S M; Reimer, O; Renaud, M; Reyes, R de los; Rieger, F; Ripken, J; Rob, L; Rosier-Lees, S; Rowell, G; Rudak, B; Rulten, C B; Ruppel, J; Ryde, F; Sahakian, V; Santangelo, A; Schlickeiser, R; Schoeck, F M; Schoenwald, A; Schwanke, U; Schwarzburg, S; Schwemmer, S; Shalchi, A; Sushch, I; Sikora, M; Skilton, J L; Sol, H; Stawarz, L; Steenkamp, R; Stegmann, C; Stinzing, F; Szostek, A; Tam, P H; Tavernet, J -P; Terrier, R; Tibolla, O; Tluczykont, M; Valerius, K; van Eldik, C; Vasileiadis, G; Venter, C; Venter, L; Vialle, J P; Viana, A; Vincent, P; Vivier, M; Voelk, H J; Volpe, F; Vorobiov, S; Wagner, S J; Ward, M; Zdziarski, A A; Zech, A; Zechlin, H -S

    2010-01-01

    AIMS: The properties of the broad-band emission from the high-frequency peaked BL Lac H 2356-309 (z=0.165) are investigated. METHODS: Very High Energy (VHE; E > 100 GeV) observations of H 2356-309 were performed with the High Energy Stereoscopic System (HESS) from 2004 through 2007. Simultaneous optical/UV and X-ray observations were made with the XMM-Newton satellite on June 12/13 and June 14/15, 2005. NRT radio observations were also contemporaneously performed in 2005. ATOM optical monitoring observations were also made in 2007. RESULTS: A strong VHE signal, ~13 sigma total, was detected by HESS after the four years HESS observations (116.8 hrs live time). The integral flux above 240 GeV is I(>240 GeV) = (3.06 +- 0.26 {stat} +- 0.61 {syst}) x 10^{-12} cm^{-2} s^{-1}, corresponding to ~1.6% of the flux observed from the Crab Nebula. A time-averaged energy spectrum is measured from 200 GeV to 2 TeV and is characterized by a power law (photon index of Gamma = 3.06 +- 0.15 {stat} +- 0.10 {syst}). Significant s...

  8. A cooperative control algorithm for camera based observational systems.

    SciTech Connect (OSTI)

    Young, Joseph G.

    2012-01-01

    Over the last several years, there has been considerable growth in camera based observation systems for a variety of safety, scientific, and recreational applications. In order to improve the effectiveness of these systems, we frequently desire the ability to increase the number of observed objects, but solving this problem is not as simple as adding more cameras. Quite often, there are economic or physical restrictions that prevent us from adding additional cameras to the system. As a result, we require methods that coordinate the tracking of objects between multiple cameras in an optimal way. In order to accomplish this goal, we present a new cooperative control algorithm for a camera based observational system. Specifically, we present a receding horizon control where we model the underlying optimal control problem as a mixed integer linear program. The benefit of this design is that we can coordinate the actions between each camera while simultaneously respecting its kinematics. In addition, we further improve the quality of our solution by coupling our algorithm with a Kalman filter. Through this integration, we not only add a predictive component to our control, but we use the uncertainty estimates provided by the filter to encourage the system to periodically observe any outliers in the observed area. This combined approach allows us to intelligently observe the entire region of interest in an effective and thorough manner.

  9. High-sensitivity observations of solar flare decimeter radiation

    E-Print Network [OSTI]

    Arnold O. Benz; Peter Messmer; Christian Monstein

    2000-12-05

    A new acousto-optic radio spectrometer has observed the 1 - 2 GHz radio emission of solar flares with unprecedented sensitivity. The number of detected decimeter type III bursts is greatly enhanced compared to observations by conventional spectrometers observing only one frequency at the time. The observations indicate a large number of electron beams propagating in dense plasmas. For the first time, we report weak, reversed drifting type III bursts at frequencies above simultaneous narrowband decimeter spikes. The type III bursts are reliable signatures of electron beams propagating downward in the corona, apparently away from the source of the spikes. The observations contradict the most popular spike model that places the spike sources at the footpoints of loops. Conspicuous also was an apparent bidirectional type U burst forming a fish-like pattern. It occurs simultaneously with an intense U-burst at 600-370 MHz observed in Tremsdorf. We suggest that it intermodulated with strong terrestrial interference (cellular phones) causing a spurious symmetric pattern in the spectrogram at 1.4 GHz. Symmetric features in the 1 - 2 GHz range, some already reported in the literature, therefore must be considered with utmost caution.

  10. Observational evidence for return currents in solar flare loops

    E-Print Network [OSTI]

    Marina Battaglia; Arnold O. Benz

    2008-06-11

    Context: The common flare scenario comprises an acceleration site in the corona and particle transport to the chromosphere. Using satellites available to date it has become possible to distinguish between the two processes of acceleration and transport, and study the particle propagation in flare loops in detail, as well as complete comparisons with theoretical predictions. Aims: We complete a quantitative comparison between flare hard X-ray spectra observed by RHESSI and theoretical predictions. This enables acceleration to be distinguished from transport and the nature of transport effects to be explored. Methods: Data acquired by the RHESSI satellite were analyzed using full sun spectroscopy as well as imaging spectroscopy methods. Coronal source and footpoint spectra of well observed limb events were analyzed and quantitatively compared to theoretical predictions. New concepts are introduced to existing models to resolve discrepancies between observations and predictions. Results: The standard thin-thick target solar flare model cannot explain the observations of all events. In the events presented here, propagation effects in the form of non-collisional energy loss are of importance to explain the observations. We demonstrate that those energy losses can be interpreted in terms of an electric field in the flare loop. One event seems consistent with particle propagation or acceleration in lower than average density in the coronal source. Conclusions: We find observational evidence for an electric field in flare loops caused by return currents.

  11. Observation of low magnetic field density peaks in helicon plasma

    SciTech Connect (OSTI)

    Barada, Kshitish K.; Chattopadhyay, P. K.; Ghosh, J.; Kumar, Sunil; Saxena, Y. C. [Institute for Plasma Research, Bhat, Gandhinagar 382428 (India)

    2013-04-15

    Single density peak has been commonly observed in low magnetic field (<100 G) helicon discharges. In this paper, we report the observations of multiple density peaks in low magnetic field (<100 G) helicon discharges produced in the linear helicon plasma device [Barada et al., Rev. Sci. Instrum. 83, 063501 (2012)]. Experiments are carried out using argon gas with m = +1 right helical antenna operating at 13.56 MHz by varying the magnetic field from 0 G to 100 G. The plasma density varies with varying the magnetic field at constant input power and gas pressure and reaches to its peak value at a magnetic field value of {approx}25 G. Another peak of smaller magnitude in density has been observed near 50 G. Measurement of amplitude and phase of the axial component of the wave using magnetic probes for two magnetic field values corresponding to the observed density peaks indicated the existence of radial modes. Measured parallel wave number together with the estimated perpendicular wave number suggests oblique mode propagation of helicon waves along the resonance cone boundary for these magnetic field values. Further, the observations of larger floating potential fluctuations measured with Langmuir probes at those magnetic field values indicate that near resonance cone boundary; these electrostatic fluctuations take energy from helicon wave and dump power to the plasma causing density peaks.

  12. "Observing and Analyzing" Images From a Simulated High Redshift Universe

    E-Print Network [OSTI]

    Morgan, Robert J; Scannapieco, Evan; Thacker, Robert J

    2015-01-01

    We investigate the high-redshift evolution of the restframe UV-luminosity function (LF) of galaxies via hydrodynamical cosmological simulations, coupled with an emulated observational astronomy pipeline that provides a direct comparison with observations. We do this by creating mock images and synthetic galaxy catalogs of approximately 100 square arcminute fields from the numerical model at redshifts ~ 4.5 to 10.4. We include the effects of dust extinction and the point spread function (PSF) for the Hubble WFC3 camera for comparison with space observations. We also include the expected zodiacal background to predict its effect on space observations, including future missions such as the James Webb Space Telescope (JWST). When our model catalogs are fitted to Schechter function parameters, we predict that the faint-end slope alpha of the LF evolves as alpha = -1.16 - 0.12 z over the redshift range z ~ 4.5 to 7.7, in excellent agreement with observations from e.g., Hathi et al. (2010). However, for redshifts z ...

  13. Control Landscapes for Observable Preparation with Open Quantum Systems

    E-Print Network [OSTI]

    Rebing Wu; Alexander Pechen; Herschel Rabitz; Michael Hsieh; Benjamin Tsou

    2007-08-16

    A quantum control landscape is defined as the observable as a function(al) of the system control variables. Such landscapes were introduced to provide a basis to understand the increasing number of successful experiments controlling quantum dynamics phenomena. This paper extends the concept to encompass the broader context of the environment having an influence. For the case that the open system dynamics are fully controllable, it is shown that the control landscape for open systems can be lifted to the analysis of an equivalent auxiliary landscape of a closed composite system that contains the environmental interactions. This inherent connection can be analyzed to provide relevant information about the topology of the original open system landscape. Application to the optimization of an observable expectation value reveals the same landscape simplicity observed in former studies on closed systems. In particular, no false sub-optimal traps exist in the system control landscape when seeking to optimize an observable, even in the presence of complex environments. Moreover, a quantitative study of the control landscape of a system interacting with a thermal environment shows that the enhanced controllability attainable with open dynamics significantly broadens the range of the achievable observable values over the control landscape.

  14. Observation of Coherence in the Photosystem II Reaction Center

    E-Print Network [OSTI]

    Franklin D. Fuller; Jie Pan; S. Seckin Senlik; Daniel E. Wilcox; Jennifer P. Ogilvie

    2013-10-03

    Photosynthesis powers life on our planet. The basic photosynthetic architecture comprises antenna complexes to harvest solar energy and reaction centers to convert the energy into a stable charge separated state. In oxygenic photosynthesis, the initial charge separation event occurs in the photosystem II reaction center; the only known natural enzyme that uses solar energy to split water. Energy transfer and charge separation in photosynthesis are rapid and have high quantum efficiencies. Recently, nonlinear spectroscopic experiments have suggested that electronic coherence may play a role in energy transfer efficiency in antenna complexes. Here we report the observation of coherence in the photosystem II reaction center by two dimensional electronic spectroscopy. The frequencies of the observed coherences match exciton difference frequencies and/or known vibrational modes of the photosystem II reaction center. These observations raise questions about the possible role of electronic and/or vibrational coherence in the fundamental charge separation process in oxygenic photosynthesis.

  15. Filtering with Marked Point Process Observations via Poisson Chaos Expansion

    SciTech Connect (OSTI)

    Sun Wei; Zeng Yong; Zhang Shu

    2013-06-15

    We study a general filtering problem with marked point process observations. The motivation comes from modeling financial ultra-high frequency data. First, we rigorously derive the unnormalized filtering equation with marked point process observations under mild assumptions, especially relaxing the bounded condition of stochastic intensity. Then, we derive the Poisson chaos expansion for the unnormalized filter. Based on the chaos expansion, we establish the uniqueness of solutions of the unnormalized filtering equation. Moreover, we derive the Poisson chaos expansion for the unnormalized filter density under additional conditions. To explore the computational advantage, we further construct a new consistent recursive numerical scheme based on the truncation of the chaos density expansion for a simple case. The new algorithm divides the computations into those containing solely system coefficients and those including the observations, and assign the former off-line.

  16. TANAMI: Milliarcsecond Resolution Observations of Extragalactic Gamma-ray Sources

    E-Print Network [OSTI]

    Ojha, Roopesh; Böck, M; Booth, R; Dutka, M S; Edwards, P G; Fey, A L; Fuhrmann, L; Gaume, R A; Hase, H; Horiuchi, S; Jauncey, D L; Johnston, K J; Katz, U; Lister, M; Lovell, J E J; Müller, C; Plötz, C; Quick, J F H; Ros, E; Taylor, G B; Thompson, D J; Tingay, S J; Tosti, G; Tzioumis, A K; Wilms, J; Zensus, J A

    2010-01-01

    The TANAMI (Tracking AGN with Austral Milliarcsecond Interferometry) and associated programs provide comprehensive radio monitoring of extragalactic gamma-ray sources south of declination -30 degrees. Joint quasi-simultaneous observations between the Fermi Gamma-ray Space Telescope and ground based observatories allow us to discriminate between competing theoretical blazar emission models. High resolution VLBI observations are the only way to spatially resolve the sub-parsec level emission regions where the high-energy radiation originates. The gap from radio to gamma-ray energies is spanned with near simultaneous data from the Swift satellite and ground based optical observatories. We present early results from the TANAMI program in the context of this panchromatic suite of observations.

  17. Ground-based observations of Kepler asteroseismic targets

    E-Print Network [OSTI]

    Uytterhoeven, K; Southworth, J; Randall, S; Ostensen, R; Molenda-Zakowicz, J; Marconi, M; Kurtz, D W; Kiss, L; Gutierrez-Soto, J; Frandsen, S; De Cat, P; Bruntt, H; Briquet, M; Zhang, X B; Telting, J H; Steslicki, M; Ripepi, V; Pigulski, A; Paparo, M; Oreiro, R; Choong, Ngeow Chow; Niemczura, E; Nemec, J; Narwid, A; Mathias, P; Martin-Ruiz, S; Lehman, H; Kopacki, G; Karoff, C; Jackiewicz, J; Henden, A A; Handler, G; Grigachene, A; Green, E M; Garrido, R; Machado, L Fox; Debosscher, J; Creevey, O L; Catanzaro, G; Bognar, Z; Biazzo, K; Bernabei, S

    2010-01-01

    We present the ground-based activities within the different working groups of the Kepler Asteroseismic Science Consortium (KASC). The activities aim at the systematic characterization of the 5000+ KASC targets, and at the collection of ground-based follow-up time-series data of selected promising Kepler pulsators. So far, 35 different instruments at 30 telescopes on 22 different observatories in 12 countries are in use, and a total of more than 530 observing nights has been awarded. (Based on observations made with the Isaac Newton Telescope, William Herschel Telescope, Nordic Optical Telescope, Telescopio Nazionale Galileo, Mercator Telescope (La Palma, Spain), and IAC-80 (Tenerife, Spain). Also based on observations taken at the observatories of Sierra Nevada, San Pedro Martir, Vienna, Xinglong, Apache Point, Lulin, Tautenburg, Loiano, Serra la Nave, Asiago, McDonald, Skinakas, Pic du Midi, Mauna Kea, Steward Observatory, Bialkow Observatory of the Wroclaw University, Piszkesteto Mountain Station, Observato...

  18. Anomalous transport and observable average in the standard map

    E-Print Network [OSTI]

    Lydia Bouchara; Ouerdia Ourrad; Sandro Vaienti; Xavier Leoncini

    2015-09-02

    The distribution of finite time observable averages and transport in low dimensional Hamiltonian systems is studied. Finite time observable average distributions are computed, from which an exponent $\\alpha$ characteristic of how the maximum of the distributions scales with time is extracted. To link this exponent to transport properties, the characteristic exponent $\\mu(q)$ of the time evolution of the different moments of order $q$ related to transport are computed. As a testbed for our study the standard map is used. The stochasticity parameter $K$ is chosen so that either phase space is mixed with a chaotic sea and islands of stability or with only a chaotic sea. Our observations lead to a proposition of a law relating the slope in $q=0$ of the function $\\mu(q)$ with the exponent $\\alpha$.

  19. IRS observations of the LMC planetary nebula SMP83

    E-Print Network [OSTI]

    J. Bernard-Salas; J. R. Houck; P. W. Morris; G. C. Sloan; S. R. Pottasch; D. J. Barry

    2004-06-07

    The first observations of the infrared spectrum of the LMC planetary nebula SMP83 as observed by the recently launched Spitzer Space Telescope are presented. The high resolution R~600 spectrum shows strong emission lines but no significant continuum. The infrared fine structure lines are used, together with published optical spectra, to derive the electron temperature of the ionized gas for several ions. A correlation between the electron temperature with ionization potential is found. Ionic abundances for the observed infrared ions have been derived and the total neon and sulfur abundances have been determined. These abundances are compared to average LMC abundances of HII regions to better understand the chemical evolution of these elements. The nature of the progenitor star is also discussed.

  20. A digital video system for observing and recording occultations

    E-Print Network [OSTI]

    Barry, M A; Pavlov, Hristo; Hanna, William; McEwan, Alistair; Filipovic, Miroslav

    2015-01-01

    Stellar occultations by asteroids and outer solar system bodies can offer ground based observers with modest telescopes and camera equipment the opportunity to probe the shape, size, atmosphere and attendant moons or rings of these distant objects. The essential requirements of the camera and recording equipment are: good quantum efficiency and low noise, minimal dead time between images, good horological faithfulness of the image time stamps, robustness of the recording to unexpected failure, and low cost. We describe the Astronomical Digital Video occultation observing and recording System (ADVS) which attempts to fulfil these requirements and compare the system with other reported camera and recorder systems. Five systems have been built, deployed and tested over the past three years, and we report on three representative occultation observations: one being a 9 +/-1.5 second occultation of the trans-Neptunian object 28978 Ixion (mv=15.2) at 3 seconds per frame, one being a 1.51 +/-0.017 second occultation ...

  1. Infrared freezing of Euclidean observables and analyticity in perturbative QCD

    E-Print Network [OSTI]

    Irinel Caprini; Jan Fischer

    2006-12-21

    The renormalization-group improved finite order expansions of the QCD observables have an unphysical singularity in the Euclidean region, due to the Landau pole of the running coupling. Recently it was claimed that, by using a modified Borel representation, the leading one-chain term in a skeleton expansion of the Euclidean QCD observables is finite and continuous across the Landau pole, and then exhibits an infrared freezing behaviour, vanishing at $Q^2=0$. In the present paper we show, using for illustration the Adler-${\\cal D}$ function, that the above Borel prescription violates the causality properties expressed by energy-plane analyticity: the function ${\\cal D}(Q^2)$ thus defined is the boundary value of a piecewise analytic function in the complex plane, instead of being a standard analytic function. So, the price to be paid for the infrared freezing of Euclidean QCD observables is the loss of a fundamental property of local quantum field theory.

  2. SIMULATING PROTOSTELLAR JETS SIMULTANEOUSLY AT LAUNCHING AND OBSERVATIONAL SCALES

    SciTech Connect (OSTI)

    Ramsey, Jon P.; Clarke, David A. [Institute for Computational Astrophysics, Department of Astronomy and Physics, Saint Mary's University, Halifax, Nova Scotia B3H 3C3 (Canada)

    2011-02-10

    We present the first 2.5-dimensional magnetohydrodynamic (MHD) simulations of protostellar jets that include both the region in which the jet is launched magnetocentrifugally at scale lengths <0.1 AU and where the propagating jet is observed at scale lengths >10{sup 3} AU. These simulations, performed with the new adaptive mesh refinement MHD code AZEuS, reveal interesting relationships between conditions at the disk surface, such as the magnetic field strength, and direct observables such as proper motion, jet rotation, jet radius, and mass flux. By comparing these quantities with observed values, we present direct numerical evidence that the magnetocentrifugal launching mechanism is capable, by itself, of launching realistic protostellar jets.

  3. Fermi GBM Observations of Terrestrial Gamma-ray Flashes

    SciTech Connect (OSTI)

    Briggs, Michael S. [CSPAR, NSSTC, 320 Sparkman Drive, Huntsville, AL 35805 (United States)

    2011-09-21

    Terrestrial Gamma-ray Flashes are short pulses of energetic radiation associated with thunderstorms and lightning. While the Gamma-ray Burst Monitor (GBM) on Fermi was designed to observe gamma-ray bursts, its large BGO detectors are excellent for observing TGFs. Using GBM, TGF pulses are seen to either be symmetrical or have faster rise time than fall times. Some TGFs are resolved into double, partially overlapping pulses. Using ground-based radio observations of lightning from the World Wide Lightning Location Network (WWLLN), TGFs and their associated lightning are found to be simultaneous to {approx_equal}40 {mu} s. The lightning locations are typically within 300 km of the sub-spacecraft point.

  4. FERMI LARGE AREA TELESCOPE OBSERVATIONS OF GRB 110625A

    SciTech Connect (OSTI)

    Tam, P. H. T.; Kong, A. K. H. [Institute of Astronomy and Department of Physics, National Tsing Hua University, Hsinchu 30013, Taiwan (China); Fan Yizhong, E-mail: phtam@phys.nthu.edu.tw [Purple Mountain Observatory, Chinese Academy of Sciences, Nanjing 210008 (China)

    2012-08-01

    Gamma-ray bursts (GRBs) that emit photons at GeV energies form a small but significant population of GRBs. However, the number of GRBs whose GeV-emitting period is simultaneously observed in X-rays remains small. We report {gamma}-ray observations of GRB 110625A using Fermi's Large Area Telescope in the energy range 100 MeV-20 GeV. Gamma-ray emission at these energies was clearly detected using data taken between 180 s and 580 s after the burst, an epoch after the prompt emission phase. The GeV light curve differs from a simple power-law decay, and probably consists of two emission periods. Simultaneous Swift X-Ray Telescope observations did not show flaring behaviors as in the case of GRB 100728A. We discuss the possibility that the GeV emission is the synchrotron self-Compton radiation of underlying ultraviolet flares.

  5. VERITAS Observations of the Nova in V407 Cygni

    E-Print Network [OSTI]

    Aliu, E; Arlen, T; Aune, T; Beilicke, M; Benbow, W; Bouvier, A; Bradbury, S M; Buckley, J H; Bugaev, V; Byrum, K; Cannon, A; Cesarini, A; Ciupik, L; Collins-Hughes, E; Connolly, M P; Cui, W; Decerprit, G; Dickherber, R; Duke, C; Dumm, J; Dwarkadas, V V; Errando, M; Falcone, A; Feng, Q; Finley, J P; Finnegan, G; Fortson, L; Furniss, A; Galante, N; Gall, D; Godambe, S; Griffin, S; Grube, J; Gyuk, G; Hanna, D; Holder, J; Huan, H; Hughes, G; Humensky, T B; Kaaret, P; Karlsson, N; Kertzman, M; Khassen, Y; Kieda, D; Krawczynski, H; Krennrich, F; Lang, M J; Lee, K; Maier, G; Majumdar, P; McArthur, S; McCann, A; Millis, J; Moriarty, P; Mukherjee, R; Nuñez, P D; Ong, R A; Orr, M; Otte, A N; Pandel, D; Park, N; Perkins, J S; Pohl, M; Prokoph, H; Quinn, J; Ragan, K; Reyes, L C; Reynolds, P T; Roache, E; Rose, H J; Ruppel, J; Saxon, D B; Schroedter, M; Sembroski, G H; Skole, C; Smith, A W; Staszak, D; Telezhinsky, I; Teši?, G; Theiling, M; Thibadeau, S; Tsurusaki, K; Tyler, J; Varlotta, A; Vincent, S; Vivier, M; Wakely, S P; Ward, J E; Weekes, T C; Weinstein, A; Weisgarber, T; Welsing, R; Williams, D A; Zitzer, B

    2012-01-01

    We report on very high energy (E > 100 GeV) gamma-ray observations of V407 Cygni, a symbiotic binary that underwent a nova outburst producing 0.1-10 GeV gamma rays during 2010 March 10-26. Observations were made with the Very Energetic Radiation Imaging Telescope Array System during 2010 March 19-26 at relatively large zenith angles, due to the position of V407 Cyg. An improved reconstruction technique for large zenith angle observations is presented and used to analyze the data. We do not detect V407 Cygni and place a differential upper limit on the flux at 1.6 TeV of 2.3 \\times 10^(-12) erg cm^(-2) s^(-1) (at the 95% confidence level). When considered jointly with data from Fermi-LAT, this result places limits on the acceleration of very high energy particles in the nova.

  6. ASTROMETRIC MASSES OF 26 ASTEROIDS AND OBSERVATIONS ON ASTEROID POROSITY

    SciTech Connect (OSTI)

    Baer, James [James Cook University, School of Engineering and Physical Sciences, Townsville, QLD 4811 (Australia); Chesley, Steven R. [Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Drive, Pasadena, CA 91109 (United States); Matson, Robert D., E-mail: jimbaer1@earthlink.net, E-mail: steve.chesley@jpl.nasa.gov [Science Applications International Corporation, 3030 Old Ranch Pkwy., Ste. 250, Seal Beach, CA 90740 (United States)

    2011-05-15

    As an application of our recent observational error model, we present the astrometric masses of 26 main-belt asteroids. We also present an integrated ephemeris of 300 large asteroids, which was used in the mass determination algorithm to model significant perturbations from the rest of the main belt. After combining our mass estimates with those of other authors, we study the bulk porosities of over 50 main-belt asteroids and observe that asteroids as large as 300 km in diameter may be loose aggregates. This finding may place specific constraints on models of main-belt collisional evolution. Additionally, we observe that C-group asteroids tend to have significantly higher macroporosity than S-group asteroids.

  7. Genuine CP-odd Observables at the LHC

    E-Print Network [OSTI]

    Tao Han; Yingchuan Li

    2009-11-16

    We discuss how to construct genuine CP-odd observables at the LHC. We classify the observables according to the even and odd properties under the naive T-transformation (\\hat{T}). There are two classes of observables of our interests: CP-odd and \\hat{T}-even; CP-odd and \\hat{T}-odd. We expect them to have broad applications to many processes in theories beyond Standard Model with CP violation. For the purpose of illustration, we use simple example of W+W- production and subsequent decays at the LHC, where the CP violation effects are parameterized by effective CP-violating operators of WWZ coupling. We find significant sensitivity to the CP-odd couplings.

  8. Evaluation of entanglement measures by a single observable

    E-Print Network [OSTI]

    Chengjie Zhang; Sixia Yu; Qing Chen; Haidong Yuan; C. H. Oh

    2015-06-04

    We present observable lower bounds for several entanglement measures including entanglement of formation, geometric measure of entanglement, concurrence, and convex-roof extended negativity. The lower bounds facilitate estimates of these entanglement measures for arbitrary finite-dimensional bipartite states. Moreover, these lower bounds can be easily obtained from the expectation value of a single observable, and the optimal lower bounds relate to fully entangled fraction. Based on our results, we use the real experimental measurement data reported by Tonolini \\textit{et al.} [Sci. Rep. \\textbf{4}, 6542 (2014)] to get the lower bounds of entanglement measures for their experimentally realized state. In addition, we also study the relations between entanglement measures.

  9. Observation of excited states in /sup 128/Ba

    SciTech Connect (OSTI)

    Zhao Zhi-zheng; Guo Ying-xiang; Pan Zong-you; Xiao Jian-min; Lei Xiang-guo; Liu Hong-ye; Sun Xi-jun

    1987-01-01

    Excited states in /sup 128/Ba have been investigated via the /sup 120/Sn (/sup 12/C, 4n..gamma..) /sup 128/Ba reaction by means of in-beam gamma spectroscopy. A 12/sup +/ state other than the previously reported one is observed according to the properties of the 935.0 keV ..gamma..-ray. It does not belong to the ground-state band. Two new interband transitions, 224.8 keV and 632.7 keV, are observed and assigned to sidefeeding between the negative-parity band and ground-state band.

  10. Notes on Deterministic Programming of Quantum Observables and Channels

    E-Print Network [OSTI]

    Teiko Heinosaari; Mikko Tukiainen

    2015-05-13

    We study the limitations of deterministic programmability of quantum circuits, e.g., quantum computer. More precisely, we analyse the programming of quantum observables and channels via quantum multimeters. We show that the programming vectors for any two different sharp observables are necessarily orthogonal, whenever post-processing is not allowed. This result then directly implies that also any two different unitary channels require orthogonal programming vectors. This approach generalizes the well-known orthogonality result first proven by Nielsen and Chuang. In addition, we give size-bounds for a multimeter to be efficient in quantum programming.

  11. First observation of excited states in {sup 182}Pb.

    SciTech Connect (OSTI)

    Jenkins, D. G.; Muikku, M.; Greenlees, P. T.; Hauschild, K.; Helarjutta, K.; Jones, P. M.; Julin, R.; Juutinen, S.; Kankaanpaa, H.; Kelsall, N. S.; Kettunen, H.; Kuusiniemi, P.; Leino, M.; Moore, C. J.; Nieminen, P.; O'Leary, C. D.; Page, R. D.; Rakhila, P.; Reviol, W.; Taylor, M. J.; Uusitalo, J.; Wadsworth, R.; Physics; Univ. of York; Univ. of Jyvaskyla; CEA Saclay; Univ. of Liverpool; Univ. of Tennessee

    2000-01-01

    Excited states in the light lead nucleus, {sup 182}Pb, have been observed for the first time, by means of the recoil-decay tagging technique. A rotational band has been observed which has features in common with bands attributed to a prolate configuration in the heavier neutron deficient lead nuclei, {sup 184-188}Pb. A variable moment of inertia fit to the states in this band suggests that the prolate minimum has risen significantly in energy compared to the next even lead nucleus, {sup 184}Pb. This constitutes firm evidence for the minimization of this configuration with respect to the spherical ground state around N=103.

  12. Observation of diamond turned OFHC copper using Scanning Tunneling Microscopy

    SciTech Connect (OSTI)

    Grigg, D.A.; Russell, P.E.; Dow, T.A.

    1988-12-01

    Diamond turned OFHC copper samples have been observed within the past few months using the Scanning Tunneling Microscope. Initial results have shown evidence of artifacts which may be used to better understand the diamond turning process. The STM`s high resolution capability and three dimensional data representation allows observation and study of surface features unobtainable with conventional profilometry systems. Also, the STM offers a better quantitative means by which to analyze surface structures than the SEM. This paper discusses findings on several diamond turned OFHC copper samples having different cutting conditions. Each sample has been cross referenced using STM and SEM.

  13. Observation of elastic collisions between lithium atoms and calcium ions

    E-Print Network [OSTI]

    Haze, Shinsuke; Fujinaga, Munekazu; Mukaiyama, Takashi

    2013-01-01

    We observed elastic collisions between laser-cooled fermionic lithium atoms and calcium ions at the energy range from 100 mK to 3 K. Lithium atoms in an optical-dipole trap were transported to the center of the ion trap using an optical tweezer technique, and a spatial overlap of the atoms and ions was realized in order to observe the atom-ion interactions. The elastic scattering rate was determined from the decay of atoms due to elastic collisions with ions. The collision-energy dependence of the elastic scattering cross-section was consistent with semi-classical collision theory.

  14. Measurements of jet-related observables at the LHC

    E-Print Network [OSTI]

    Kokkas, Panagiotis

    2015-01-01

    During the first years of the LHC operation a large amount of jet data was recorded by the ATLAS and CMS experiments. In this review several measurements of jet-related observables are presented, such as multi-jet rates and cross sections, ratios of jet cross sections, jet shapes and event shape observables. All results presented here are based on jet data collected at a center-of-mass energy of 7 TeV. Data are compared to various Monte Carlo generators, as well as to theoretical next-to-leading-order calculations allowing a test of perturbative Quantum Chromodynamics in a previously unexplored energy region.

  15. Observing CP Violation in Many-Body Decays

    E-Print Network [OSTI]

    Mike Williams

    2011-05-26

    It is well known that observing CP violation in many-body decays could provide strong evidence for physics beyond the Standard Model. Many searches have been carried out; however, no 5sigma evidence for CP violation has yet been found in these types of decays. A novel model-independent method for observing CP violation in many-body decays is presented in this paper. It is shown that the sensitivity of this method is significantly larger than those used to-date.

  16. Observation of inertial energy cascade in interplanetary space plasma

    E-Print Network [OSTI]

    Luca Sorriso-Valvo; Raffaele Marino; Vincenzo Carbone; Fabio Lepreti; Pierluigi Veltri; Alain Noullez; Roberto Bruno; Bruno Bavassano; Ermanno Pietropaolo

    2007-02-09

    We show in this article direct evidence for the presence of an inertial energy cascade, the most characteristic signature of hydromagnetic turbulence (MHD), in the solar wind as observed by the Ulysses spacecraft. After a brief rederivation of the equivalent of Yaglom's law for MHD turbulence, we show that a linear relation is indeed observed for the scaling of mixed third order structure functions involving Els\\"asser variables. This experimental result, confirming the prescription stemming from a theorem for MHD turbulence, firmly establishes the turbulent character of low-frequency velocity and magnetic field fluctuations in the solar wind plasma.

  17. Observationally based assessment of polar amplification of global warming

    E-Print Network [OSTI]

    Bhatt, Uma

    Observationally based assessment of polar amplification of global warming Igor V. Polyakov,1) are similar, and do not support the predicted polar amplification of global warming. The possible moderating amplification of global warming. Intrinsic arctic variability obscures long-term changes, limiting our ability

  18. NOAA/NMFS Developments NOAA Observes Fifth Anniversary of Oceanic,

    E-Print Network [OSTI]

    of the oceans, coastal waters, and estuaries. investigating their currents, the structure and con- toursNOAA/NMFS Developments NOAA Observes Fifth Anniversary of Oceanic, Atmospheric, and Environmental Activities NOAA, the National Oceanic and Atmospheric Administration, cele- brated its fifth anniversary 3

  19. Supporting An Integrated Paper-Digital Workflow for Observational Research

    E-Print Network [OSTI]

    Hollan, Jim

    Supporting An Integrated Paper-Digital Workflow for Observational Research Nadir Weibel, Adam Fouse digital recording de- vices and storage facilities, is revolutionizing our ability to collect and analyze cognition and radically improve information-intensive work. In this paper we introduce a system to aid

  20. Geoinformation Science and Earth Observation for municipal risk management;

    E-Print Network [OSTI]

    1 Geoinformation Science and Earth Observation for municipal risk management; The SLARIM project Dr for flood risk management, and the cities of Lalitpur in Nepal and Dehradun in India for seismic risk is to present the first results of a research project entitled: Strengthening Local Authorities in Risk

  1. NOTE / NOTE New observations on urine contents in water-

    E-Print Network [OSTI]

    Vatnick, Itzick

    NOTE / NOTE New observations on urine contents in water- deprived Negev Desert rodents Carmi Korine of the murid subfamilies Gerbillinae and Cricetomyinae from the Namib Desert, when deprived of water, excreted much water. This phenomenon has not been reported in other rodents, and whether it is a trait

  2. 2000: PUBLICATIONS WITH RESULTS FROM USERS' IRAM OBSERVATIONS

    E-Print Network [OSTI]

    RadioAstronomie Millimétrique, Institut de (IRAM)

    2000: PUBLICATIONS WITH RESULTS FROM USERS' IRAM OBSERVATIONS 773. MOLECULAR BULLETS IN THE PLANETARY NEBULA BD+30°3639 R. Bachiller, T. Forveille, P.J. Huggins, P. Cox, J.P. Maillard 2000, A&A 353, L. Kerschbaum, H. Olofsson 2000, A&A 353, 257 775. CO CONTENT OF BIPOLAR PLANETARY NEBULAE E. Josselin, R

  3. Quantile Regression for Correlated Observations , Lee-Jen Wei2

    E-Print Network [OSTI]

    Wolfe, Patrick J.

    Quantile Regression for Correlated Observations Li Chen1 , Lee-Jen Wei2 , and Michael I. Parzen 1 60637 Abstract In this paper, we consider the problem of regression analysis for data which consist the standard mean regression, we regress various percentiles of each marginal response variable over its

  4. Observation of B ->phi K and B ->phi K

    E-Print Network [OSTI]

    Ammar, Raymond G.; Bean, Alice; Besson, David Zeke

    2001-04-01

    We have studied two-body charmless hadronic decays of R mesons into the final states phiK and phiK(*). Using 9.7 million B (B) over bar pairs collected with the CLEO II detector, we observe the decays B- --> phiK(-) and ...

  5. Ideal Observers for Detecting Human Motion: Correspondence Noise.

    E-Print Network [OSTI]

    Yuille, Alan L.

    purpose, models of motion. We perform more psychophysical experiments which are consistent with humansIdeal Observers for Detecting Human Motion: Correspondence Noise. HongJing Lo Department obtain Barlow and Tripathy's classic model as an approximation. Our psychophysical experiments show

  6. Observation and Imitation: Goal Sequence Learning in Neurally Controlled Construction

    E-Print Network [OSTI]

    Crabbe, Frederick

    Observation and Imitation: Goal Sequence Learning in Neurally Controlled Construction Animats: VI, bring them to the construction site, locate the correct loca­ tion for the building material, and add it to the struc­ ture. The motivation for this work is to create agents that can perform construction tasks while

  7. Tropospheric carbon monoxide: satellite observations and their applications 

    E-Print Network [OSTI]

    MacCallum, Stuart Neil

    2008-01-01

    of greenhouse gases such as CH4 and O3. Consequently, CO has an atmospheric lifetime of 1-3 months, making it a good tracer for studying the long range transport of pollution. Satellite observations present a valuable tool to investigate tropospheric CO...

  8. Global observations of desert dust and biomass burning aerosols

    E-Print Network [OSTI]

    Graaf, Martin de

    and desert dust observations from GOME and SCIAMACHY · Conclusions and Outlook #12; · Absorbing Aerosol Transfer Model Solar zenith angle = 30° Viewing zenith angle = 0° Surface albedo = 5% #12;Reflectance at TOA with absorbing aerosols Doubling-Adding KNMI Radiative Transfer Model Solar zenith angle = 30

  9. Observing The Cosmic Ray Moon Shadow With VERITAS

    E-Print Network [OSTI]

    Bird, Ralph

    2015-01-01

    The Earth is subjected to a uniform flux of very-high-energy (VHE, E > 100 GeV) cosmic rays unless they are obscured by an object, such as the Moon, in which case a deficit or shadow is created. Since cosmic rays are charged this deficit is deflected by the Earth's magnetic field, enabling the rigidity of the obstructed cosmic rays to be determined. Measurement of the relative deficits of different species enables the positron fraction and the antiproton ratio to be measured. The April 15, 2014 lunar eclipse was visible with the VERITAS Cherenkov telescopes, which allowed (with special UV bandpass filters) 74 minutes of direct observations of the Moon and the associated deficit in the cosmic-ray flux. The results of this observation are presented. In addition VERITAS has been conducting a series of observations by pointing close to a partially illuminated Moon, with a reduced photomultiplier tube high voltage and UV bandpass filters. We present the technique developed for these observations and their current ...

  10. Biooptical observations of the 2004 Labrador Sea phytoplankton bloom

    E-Print Network [OSTI]

    Boss, Emmanuel S.

    showed an additional midJune peak in zooplankton biomass which was attributed to egglaying copepods increasingly important as these deployments become more commonplace via ocean observing systems. Moreover that during the bloom, 47 mmol C m-2 d-1 was assimilated into biomass and was rapidly exported, and that all

  11. Coronal Trapping of Energetic Flare Particles: Yohkoh/HXT Observations

    E-Print Network [OSTI]

    Metcalf, Thomas R.

    the energization of the solar corona. The most common interpretation for the production of the observed HXR fluxes Alexander Lockheed Martin Solar and Astrophysics Laboratory, Department H1­12, Bldg. 252, 3251 Hanover St in a search for spectral evidence of the coronal trapping of energetic particles during solar flares. Two

  12. Mountains on Titan: Modeling and observations Giuseppe Mitri,1

    E-Print Network [OSTI]

    Mountains on Titan: Modeling and observations Giuseppe Mitri,1 Michael T. Bland,2 Adam P. Showman,3. Showman, J. Radebaugh, B. Stiles, R. M. C. Lopes, J. I. Lunine, and R. T. Pappalardo (2010), Mountains. Introduction [2] The Cassini Radar instrument has imaged mountainous topography on Saturn's moon Titan

  13. Unusual Solar Radio Burst Observed at Decameter Wavelengths

    E-Print Network [OSTI]

    Melnik, V N; Konovalenko, A A; Rucker, H O; Frantsuzenko, A V; Dorovskyy, V V; Panchenko, M; Stanislavskyy, A A

    2015-01-01

    An unusual solar burst was observed simultaneously by two decameter radio telescopes UTR-2 (Kharkov, Ukraine) and URAN-2 (Poltava, Ukraine) on 3 June 2011 in the frequency range 16-28 MHz. The observed radio burst has some unusual properties, which are not typical for the other types of solar radio bursts. The frequency drift rate of it was positive (about 500 kHz s$^{-1}$) at frequencies higher than 22 MHz and negative (100 kHz s$^{-1}$) at lower frequencies. The full duration of this event varies from 50 s up to 80 s, depending on the frequency. The maximum radio flux of the unusual burst reaches $\\approx 10^3$ s.f.u and its polarization does not exceed 10%. This burst has a fine frequency-time structure of unusual appearance. It consists of stripes with the frequency bandwidth 300-400 kHz. We consider that several accompanied radio and optical events observed by SOHO and STEREO spacecraft are possibly associated with the reported radio burst. A model that may interpret the observed unusual solar radio burs...

  14. Autonomous observations of the ocean biological carbon pump

    SciTech Connect (OSTI)

    Bishop, James K.B.

    2009-03-01

    Prediction of the substantial biologically mediated carbon flows in a rapidly changing and acidifying ocean requires model simulations informed by observations of key carbon cycle processes on the appropriate space and time scales. From 2000 to 2004, the National Oceanographic Partnership Program (NOPP) supported the development of the first low-cost fully-autonomous ocean profiling Carbon Explorers that demonstrated that year-round real-time observations of particulate organic carbon (POC) concentration and sedimentation could be achieved in the world's ocean. NOPP also initiated the development of a sensor for particulate inorganic carbon (PIC) suitable for operational deployment across all oceanographic platforms. As a result, PIC profile characterization that once required shipboard sample collection and shipboard or shore based laboratory analysis, is now possible to full ocean depth in real time using a 0.2W sensor operating at 24 Hz. NOPP developments further spawned US DOE support to develop the Carbon Flux Explorer, a free-vehicle capable of following hourly variations of particulate inorganic and organic carbon sedimentation from near surface to kilometer depths for seasons to years and capable of relaying contemporaneous observations via satellite. We have demonstrated the feasibility of real time - low cost carbon observations which are of fundamental value to carbon prediction and when further developed, will lead to a fully enhanced global carbon observatory capable of real time assessment of the ocean carbon sink, a needed constraint for assessment of carbon management policies on a global scale.

  15. Are we observing Lorentz violation in gamma ray bursts?

    E-Print Network [OSTI]

    Theodore G. Pavlopoulos

    2005-08-12

    From recent observations of gamma-ray bursts (GRBs), it appears that spectral time lags between higher-energy gamma rays photons and lower-energy photons vary with energy difference and time (distance) traveled. These lags appear to be smaller for the most luminous (close) bursts but larger for the fainter (farther away) bursts. From this observation, it has been suggested that it might be possible to determine the distance (L) these bursts have traveled from these time lags alone, without performing any red-shift measurements. These observed spreads (dispersion) of high-energy electromagnetic pulses of different energies with time contradict the special theory of relativity (STR). However, extended theories (ET) of the STR have been developed that contain a dispersive term, predicting the above observations. An example of such an ET is presented, allowing us to derive a relationship between time lags of gamma rays of different energies and distance L traveled from their origin. In addition, this theory predicts the origin of X-ray flashes.

  16. Coronal shock waves observed in images H. S. Hudson

    E-Print Network [OSTI]

    Hudson, Hugh

    . The large-scale coronal shock waves observed from radio type II bursts and from More- ton waves have proven surprisingly difficult to detect in coronal images. I review the evidence for such waves in radio, optical, EUV-scale waves. The discovery of radio type II bursts showed immediately that these waves became shocks

  17. Bait Loss From Halibut Longline Gear Observed From a Submersible

    E-Print Network [OSTI]

    Bait Loss From Halibut Longline Gear Observed From a Submersible WILLIAM L. HIGH Introduction Demersal longline gear is fished along the west coast of the United States for Pacific halibut is avail- able on the behavior of fish around the gear and bait, bait durability on hooks, predators other

  18. Controllers with Minimal Observation Power (Application to Timed Systems)

    E-Print Network [OSTI]

    David, Alexandre

    Controllers with Minimal Observation Power (Application to Timed Systems) Peter Bulychev1 , Franck, Danish-Chinese Center for Cyber Physical Systems (IDEA4CPS) and VKR Center of Excellence MT-LAB. #12;The iterations. We apply our approach to timed systems. We have developed a tool prototype and analyze

  19. 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.

  20. THEORETICAL INTERPRETATION OF FETCH LIMITED WINDDRIVEN SEA OBSERVATIONS

    E-Print Network [OSTI]

    Zakharov, Vladimir

    is characterized by a constant (in space and time) offshore wind at a normal angle to the straight coastline. Under article. At larger values of the wind fetch, appropriate for open ocean conditions when the advectionTHEORETICAL INTERPRETATION OF FETCH LIMITED WIND­DRIVEN SEA OBSERVATIONS V.E. Zakharov Department

  1. Global observations of the land breeze Sarah T. Gille

    E-Print Network [OSTI]

    Griesel, Alexa

    . These observations provide a global view of diurnal wind variations over the ocean. Results agree with frictional that diurnal wind variations propagate offshore progressively like nonlinear gravity waves and are detectable difference drives an onshore wind during the day and an offshore wind at night. These wind patterns, known

  2. Observable form of pulses emitted from relativistic collapsing objects

    SciTech Connect (OSTI)

    Frolov, Valeri P.; Lee, Hyun Kyu

    2005-02-15

    In this work, we discuss observable characteristics of the radiation emitted from a surface of a collapsing object. We study a simplified model in which a radiation of massless particles has a sharp in time profile, and it happens at the surface at the same moment of comoving time. Since the radiating surface has finite size the observed radiation will occur during some finite time. Its redshift and bending angle are affected by the strong gravitational field. We obtain a simple expression for the observed flux of the radiation as a function of time. To find an explicit expression for the flux we develop an analytical approximation for the bending angle and time delay for null rays emitted by a collapsing surface. In the case of the bending angle this approximation is an improved version of the earlier proposed Beloborodov-Leahy-approximation. For rays emitted at R>2R{sub g} the accuracy of the proposed improved approximations for the bending angle and time delay is of order (or less) than 2%-3%. By using this approximation we obtain an approximate analytical expression for the observed flux and study its properties.

  3. Observable Form of Pulses Emitted From Relativistic Collapsing Objects

    SciTech Connect (OSTI)

    Frolov, V.

    2005-01-28

    In this work, we discuss observable characteristics of the radiation emitted from a surface of a collapsing object. We study a simplified model in which a radiation of massless particles has a sharp in time profile and it happens at the surface at the same moment of comoving time. Since the radiating surface has finite size the observed radiation will occur during some finite time. Its redshift and bending angle are affected by the strong gravitational field. We obtain a simple expression for the observed flux of the radiation as a function of time. To find an explicit expression for the flux we develop an analytical approximation for the bending angle and time delay for null rays emitted by a collapsing surface. In the case of the bending angle this approximation is an improved version of the earlier proposed Beloborodov-Leahy-approximation. For rays emitted at R > 2R{sub g} the accuracy of the proposed improved approximations for the bending angle and time delay is of order (or less) than 2-3%. By using this approximation we obtain an approximate analytical expression for the observed flux and study its properties.

  4. Wind observations of foreshock cavities: A case study

    E-Print Network [OSTI]

    California at Berkeley, University of

    Wind observations of foreshock cavities: A case study D. G. Sibeck1 Applied Physics Laboratory seen by Wind in the dawn foreshock on 19 April 1996. A comparison with the results of hybrid in the ambient solar wind, ion temperatures do not rise greatly, thermal pressures are only slightly greater than

  5. High Beta Observations of the Hot Electron Interchange Instability

    E-Print Network [OSTI]

    been made in the presence of the magnetic levitation fields. We find the HEI mode is characterized observed in high-beta plasma created in the Levitated Dipole Experiment (LDX). We have previously that characterize these modes now incorporate fast magnetic measurements in an attempt to put together a coherent

  6. Circle criterion observer for a compression system Bjrnar Bhagen

    E-Print Network [OSTI]

    Gravdahl, Jan Tommy

    .gravdahl@itk.ntnu.no Abstract-- Observers for a compression system using turbo compressors are derived for a model that captures speed. Results are validated by simulations. I. MOTIVATION Compression systems using turbo compressors, centrifugal or axial, are exposed to the phenomenons of surge and rotating stall. Surge is an axisymmtrical

  7. Hurricanes: Observations and Dynamics Houze Section 10.1.

    E-Print Network [OSTI]

    Droegemeier, Kelvin K.

    1 Hurricanes: Observations and Dynamics Houze Section 10.1. Holton Section 9.7. Emanuel, K. A., 1988: Toward a general theory of hurricanes. American Scientist, 76, 371-379 (web link). http://ww2010.atmos.uiuc.edu/(Gh)/guides/mtr/hurr/home.rxml Definition: Hurricanes are intense vortical (rotational

  8. Observation of the radiative decay D*+-> D+gamma

    E-Print Network [OSTI]

    Ammar, Raymond G.; Baringer, Philip S.; Bean, Alice; Besson, David Zeke; Coppage, Don; Darling, C.; Davis, Robin E. P.; Kotov, S.; Kravchenko, I.; Kwak, Nowhan; Zhou, L.

    1998-05-01

    We have observed a signal for the decay D*(+) --> D(+)gamma at a significance of 4 standard deviations. From the measured branching ratio B(D*(+) --> D(+)gamma)/B(D*(+) --> D(+)pi(0)) = 0.055 +/- 0.014 +/- 0.010 we find B(D*(+) --> D(+)gamma) = 0...

  9. Statistics from Lagrangian observations J.H. LaCasce *

    E-Print Network [OSTI]

    LaCasce, Joseph H.

    Review Statistics from Lagrangian observations J.H. LaCasce * Department of Geosciences, University February 2008 Keywords: Lagrangian statistics Floats Drifters Absolute and relative dispersion a b s t r a c t We review statistical analyses of Lagrangian data from the ocean. These can be grouped

  10. Observation of objects under intense plasma background illumination

    SciTech Connect (OSTI)

    Buzhinsky, R. O.; Savransky, V. V.; Zemskov, K. I.; Isaev, A. A.; Buzhinsky, O. I.

    2010-12-15

    Experiments on the observation of a brightness-amplified image of an object through a masking arc discharge are presented. The copper-vapor laser active medium was used as an image brightness amplifier. It is shown that the image quality does not worsen under plasma background illumination.

  11. Observations of Near-Earth Asteroids Impact Hazard to Earth

    E-Print Network [OSTI]

    Throop, Henry

    Observations of Near-Earth Asteroids and the Impact Hazard to Earth Henry Throop! Physics on Earth Potchefstroom Parys Sasolburg 20 km #12;Parys 3 km #12;Vredefort Impact Crater Looking from outer Impactor? · Origin: One of several million Near Earth Asteroids (NEAs) · a = 1.6 AU; e = 0.5; i = 4

  12. Mirror Mode Structures in the Solar Wind: STEREO Observations

    E-Print Network [OSTI]

    California at Berkeley, University of

    Mirror Mode Structures in the Solar Wind: STEREO Observations O. Enríquez-Rivera1 , X. Blanco-Cano1 Autónoma de México, Coyoacán, D.F., 04510, MEXICO 2. Institute of Geophysics and Planetary Physics of California, Berkeley, CA 94720, USA Abstract. Mirror mode structures occur in the solar wind either

  13. Tropospheric ozone over the North Pacific from ozonesonde observations

    E-Print Network [OSTI]

    Liu, Hongyu

    of urban air pollution. At sites in the mid and eastern Pacific the signature of transport of polluted air, Tsukuba, and Sapporo, Japan), a site in the central Pacific (Hilo, Hawaii), and a site on the west coast very high mixing ratios of ozone were observed that result from pollution transport from China

  14. Direct observation of photoinduced bent nitrosyl excited-state complexes

    SciTech Connect (OSTI)

    Sawyer, Karma R.; Steele, Ryan P.; Glascoe, Elizabeth A.; Cahoon, James F.; Schlegel, Jacob P.; Head-Gordon, Martin; Harris, Charles B.

    2008-06-28

    Ground state structures with side-on nitrosyl ({eta}{sup 2}-NO) and isonitrosyl (ON) ligands have been observed in a variety of transition-metal complexes. In contrast, excited state structures with bent-NO ligands have been proposed for years but never directly observed. Here we use picosecond time-resolved infrared spectroscopy and density functional theory (DFT) modeling to study the photochemistry of Co(CO){sub 3}(NO), a model transition-metal-NO compound. Surprisingly, we have observed no evidence for ON and {eta}{sup 2}-NO structural isomers, but have observed two bent-NO complexes. DFT modeling of the ground and excited state potentials indicates that the bent-NO complexes correspond to triplet excited states. Photolysis of Co(CO){sub 3}(NO) with a 400-nm pump pulse leads to population of a manifold of excited states which decay to form an excited state triplet bent-NO complex within 1 ps. This structure relaxes to the ground triplet state in ca. 350 ps to form a second bent-NO structure.

  15. Technology Transfer: Observations from the TIPSTER Text Program

    E-Print Network [OSTI]

    Some Technology Transfer: Observations from the TIPSTER Text Program Dr. Sarah M. Taylor Office. Introduction Technology Transfer has been an important part of the TIPSTER Text Program from the beginning stated as a reason for the emphasis on technology transfer in the TIPSTER Program, nonetheless I think

  16. Expanding the Discovery Potential of VERITAS via Moonlight Observations

    SciTech Connect (OSTI)

    Benbow, Wystan R. [PI

    2014-10-27

    This grant partially supported the base research efforts of the Smithsonian Astrophysical Observatory (SAO), Very-High-Energy (VHE; E > 100 GeV) gamma-ray research group from 8/1/09 to 7/31/14. During the project period, the SAO gamma-ray group carried out a wide-range of research efforts, but focused on VHE observations of extragalactic sources with VERITAS. The SAO group led or co-lead nearly all VERITAS extragalactic working groups and the observations addressed themes in Particle Physics and Fundamental Laws, Cosmology, and Black Holes. The primary topics of this research were processes in exotic galaxies, especially active galactic nuclei and starburst galaxies, which have implications for cosmology and Lorentz invariance violation, as well as indirect dark matter detection via VERITAS observations of dwarf spheroidal galaxies. In addition, the SAO group let the development of unique capabilities for VERITAS to observe during all periods of moonlight. Overall, this has increased the VERITAS data yield by 60% and these data are both scientifically useful and regularly published. This grant funded research that led to contributions towards the publication of 51 refereed journal articles during the project period, including several led by, or with significant contributions from, the SAO group.

  17. Global assessment of ocean carbon export by combining satellite observations

    E-Print Network [OSTI]

    Siegel, David A.

    Global assessment of ocean carbon export by combining satellite observations and food-web models D Studies, University of Tasmania, Hobart, Tasmania, Australia Abstract The export of organic carbon from cycle. Here we introduce a mechanistic assessment of the global ocean carbon export using satellite

  18. Observations of remote and local forcing in Galveston Bay, Texas 

    E-Print Network [OSTI]

    Guannel, Gregory

    2001-01-01

    . The observations show that the subtidal water surface energy increases with decreasing frequency, and that amount of energy increases with distance towards the end of the estuary. The surface setup and the water elevation at the entrance of the bay are asymmetric...

  19. 2001: PUBLICATIONS WITH RESULTS FROM USERS' IRAM OBSERVATIONS

    E-Print Network [OSTI]

    RadioAstronomie Millimétrique, Institut de (IRAM)

    2001: PUBLICATIONS WITH RESULTS FROM USERS' IRAM OBSERVATIONS 829. WARM H2 IN THE GALACTIC CENTER. Hüttemeister 2001, A&A 365, 174 830. THE IRAM KEY-PROJECT: SMALL- SCALE STRUCTURE OF PRE-STAR FORMING REGIONS. Heithausen, E. Falgarone 2001, A&A 365, 275 831. METHODS AND CONSTRAINTS FOR THE CORRECTION OF THE ERROR BEAM

  20. Observability and Estimation Uncertainty Analysis for PMU Placement Alternatives

    E-Print Network [OSTI]

    Pollefeys, Marc

    Observability and Estimation Uncertainty Analysis for PMU Placement Alternatives Jinghe Zhang unit (PMU), developed in the 1980s, is considered to be one of the most important devices in the future of power systems. While PMU measurements currently cover fewer than 1% of the nodes in the U.S. power grid

  1. Direct observation of a widely tunable bandgap in bilayer graphene

    E-Print Network [OSTI]

    Zettl, Alex

    . Most notably, the inversion symmetric AB-stacked bilayer graphene is a zero-bandgap semiconductor in the graphene FET device we are able to control independently the two key semiconductor parameters: electronicLETTERS Direct observation of a widely tunable bandgap in bilayer graphene Yuanbo Zhang1 *, Tsung

  2. EARTH OBSERVATION 400M Indians Endangered By Ozone

    E-Print Network [OSTI]

    Singh, Ramesh P.

    has been linked to increases in skin cancer rates. All rights reserved. © 2004 United Press using satellite and limited ground observations, the Press Trust of India reported Tuesday. The rate the reasons for the depletion, th e report states. Ozone is an important atmospheric trace gas that blocks

  3. Observation of the top quark with the DO detector

    SciTech Connect (OSTI)

    Hadley, N.J. [Univ. of Maryland, College Park, MD (United States)

    1997-01-01

    The DO Collaboration reports on the observation of the top quark in p{bar p} collisions at {radical}s = 1.8 TeV at the Fermilab Tevatron. We measure the top quark mass to be 199{sub -21}{sup -19}(stat){sub -21}{sup +14}(syst.) GeV/c{sup 2} and its production cross section to be 6.4 {+-}2.2 pb. Our result is based on approximately 50 pb{sup -1} of data. We observe 17 events with an expected background of 3.8 {+-} 0.6 events. The probability of an upward fluctuation of the background to produce the observed signal is 2 x 10{sup -6} (equivalent to 4.6 standard deviations). The kinematic properties of the events are consistent with top quark decay, and the distribution of events across the seven decay channels is consistent with the Standard Model top quark branching fractions. We describe the analysis that led to the observation of the top quark as well as the properties of the top quark events.

  4. The Accuracy of the Astronomical Observations of Lewis and Clark*

    E-Print Network [OSTI]

    asterisk

    2000-05-09

    These search terms have been highlighted: sextant, horizon, preston ... latitude and longitude, at all remarkable points on the river. . . . and. Your observations ..... and the planets, and even the fixed stars, are also subject to parallax,. but those ..... The idea for the Lewis and Clark expedition originated with President. Thomas ...

  5. Observational constraint on the varying speed of light theory

    E-Print Network [OSTI]

    Jing-Zhao Qi; Ming-Jian Zhang; Wen-Biao Liu

    2014-10-07

    The varying speed of light (VSL) theory is controversial. It succeeds in explaining some cosmological problems, but on the other hand it is excluded by mainstream physics because it will shake the foundation of physics. In the present paper, we devote ourselves to test whether the speed of light is varying from the observational data of the type Ia Supernova, Baryon Acoustic Oscillation, Observational $H(z)$ data and Cosmic Microwave Background (CMB). We select the common form $c(t)=c_0a^n(t)$ with the contribution of dark energy and matter, where $c_0$ is the current value of speed of light, $n$ is a constant, and consequently construct a varying speed of light dark energy model (VSLDE). The combined observational data show a much trivial constraint $n=-0.0033 \\pm 0.0045$ at 68.3\\% confidence level, which indicates that the speed of light may be a constant with high significance. By reconstructing the time-variable $c(t)$, we find that the speed of light almost has no variation for redshift $z light is only in order of $10^{-2}$. We also introduce the geometrical diagnostic $Om (z)$ to show the difference between the VSLDE and $\\Lambda$CDM model. The result shows that the current data are difficult to differentiate them. All the results show that the observational data favor the constant speed of light.

  6. OBSERVING LYAPUNOV EXPONENTS OF INFINITE-DIMENSIONAL DYNAMICAL SYSTEMS

    E-Print Network [OSTI]

    Ott, William

    OBSERVING LYAPUNOV EXPONENTS OF INFINITE-DIMENSIONAL DYNAMICAL SYSTEMS WILLIAM OTT, MAURICIO A. RIVAS, AND JAMES WEST Abstract. Can the Lyapunov exponents of infinite-dimensional dynamical systems spaces generated by evolution partial differential equations. Contents 1. Introduction 1 1.1. Lyapunov

  7. On efficient estimation of densities for sums of squared observations

    E-Print Network [OSTI]

    Schick, Anton

    On efficient estimation of densities for sums of squared observations Anton Schick and Wolfgang for each i = 1, . . . , m. Under appropriate functional versions of these conditions, Schick and Wefelmeyer function spaces. The research of Anton Schick was partially supported by NSF Grant DMS 0906551. 1 #12

  8. ON OBSERVATIONAL EQUIVALENCE AND ALGEBRAIC SPECIFICATION --Extended abstract i --

    E-Print Network [OSTI]

    Sannella, Don

    operations on nat and bool), and suppose A and B are ~-algebras with tAIbunch = the set of finite setsON OBSERVATIONAL EQUIVALENCE AND ALGEBRAIC SPECIFICATION -- Extended abstract i -- Donald Sannella which is adequate to handle reachable algebras only, and show how to extend it to cope with unreachable

  9. November 18, 2005 Chandra Observations of Magnetic Fields and Relativistic

    E-Print Network [OSTI]

    Schwartz, Daniel

    November 18, 2005 Chandra Observations of Magnetic Fields and Relativistic Beaming in Four Quasar microwave background. If particles and magnetic #12;elds are near minimum energy density 1 Harvard CSIRO Australia Telescope National Facility, PO Box 76, Epping NSW 1710, Australia 4 Jet Propulsion

  10. Hengill geothermal volcanic complex (Iceland) characterized by integrated geophysical observations

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Hengill geothermal volcanic complex (Iceland) characterized by integrated geophysical observations Cedex 02, France. 2 GeoForschungsZentrum Potsdam - Section 2.2, 14473 Potsdam, Germany. 3 Iceland GeoSurvey - ISOR , 108 Reykjavík, Iceland Abstract Structural features of volcanic and hydrothermal systems can

  11. Input Observer: Measuring Text Entry and Pointing Performance from

    E-Print Network [OSTI]

    Wobbrock, Jacob O.

    Input Observer: Measuring Text Entry and Pointing Performance from Naturalistic Everyday Computer that will be capable of measuring a user's text entry and pointing abilities from everyday computer use "in the wild for both text entry and mouse pointing. Keywords Text entry, mouse pointing, field studies, naturalistic

  12. Direct Molecular Dynamics Observation of Protein Folding Transition State Ensemble

    E-Print Network [OSTI]

    Stanley, H. Eugene

    Direct Molecular Dynamics Observation of Protein Folding Transition State Ensemble Feng Ding for the interpretation of experimental results and understanding of protein folding mechanics, which has at- tracted, 1999; Guerois and Serrano, 2000) have been proposed to predict the transition states in protein folding

  13. Microwave and hard X-ray imaging observations of

    E-Print Network [OSTI]

    White, Stephen

    Microwave and hard X-ray imaging observations of energetic electrons in solar flares: event of 2003 to nonthermal energies are seen via microwave and hard X-ray emission from the solar corona. Imaging sophisticated and fully dedicated solar radio telescope operating at microwave frequencies (17 & 34 GHz) capable

  14. Observation time scale, free-energy landscapes, and molecular symmetry

    E-Print Network [OSTI]

    Salamon, Peter

    Observation time scale, free-energy landscapes, and molecular symmetry David J. Walesa,1 and Peter structures that interconvert on a given time scale are lumped together, the corresponding free-energy surface that are connected by free-energy barriers below a certain threshold. We illustrate this time dependence for some

  15. Overview of Forest Observations in the GEOSS Work Plan

    E-Print Network [OSTI]

    do Iguaçu, Brazil #12;GEOSS societal benefits and land cover and forest observations Climate Land change & GHG emis. Water+energy exchanges Climate Land change & GHG emis. Water+energy exchanges Weather environment cond. Services + accounting Energy Bio-energy/biomass Wind/hydro power assess. Energy Bio-energy

  16. Empathic Painting: Interactive stylization through observed emotional state

    E-Print Network [OSTI]

    Collomosse, John

    Empathic Painting: Interactive stylization through observed emotional state Maria Shugrina Computer. Abstract We present the "empathic painting" -- an interactive painterly ren- dering whose appearance adapts in real time to reflect the perceived emotional state of the viewer. The empathic painting is an ex

  17. FURTHER LIMNOLOGICAL OBSERVATIONS ON THE FINGER LAKES OF NEW YORK

    E-Print Network [OSTI]

    FURTHER LIMNOLOGICAL OBSERVATIONS ON THE FINGER LAKES OF NEW YORK .:f- By Edward A. Birge ON THE FINGER LAKES OF NEW YORK. .:I- By EDWARD A. BIRGE and CHANCEY JUDAY, Wisconsin Geological and Natural the authors of the present paper to spend some weeks in the study of the Finger Lakes of New York. The results

  18. Centrifugal force reversal from the perspective of rigidly rotating observer

    E-Print Network [OSTI]

    Giorgi Dalakishvili

    2011-12-26

    In previous studies the dynamics of the relativistic particle moving along the rotating pipe was investigated. The simple gedanken experiment was considered. It was shown that at large enough velocities a centrifugal force acting on the bead changes its usual sign and attracts towards the rotation axis. The authors studied motion of the particle along the rotating straight pipe in the frame of the observer located in the center of rotation, also dynamics of centrifugally accelerated relativistic particle was studied in the laboratory frame. In the both cases it was shown that centrifugal force changes sign. Recently the problem was studied in the frame of stationary observers. It was argued that centrifugal acceleration reversal is not frame invariant effect. In the present paper we consider motion of particle along the rotating straight line in the frame of an arbitrary stationary observer located at certain distance form the center of rotation and rigidly rotating with constant angular velocity. It is shown that any stationary observer could detect reversal of centrifugal acceleration.

  19. Observations from The EV Project in Q4 2013

    SciTech Connect (OSTI)

    John Smart

    2014-02-01

    This is a summary report for The EV Project 4th quarter 2013 reports. It describes electric vehicle driver driving and charging behavior observed in Q4. It is the same report as the previously approved/published Q3 2013 report, only the numbers have been updated. It is for public release and does not have limited distribution.

  20. A NEW PARAMETRIZATION OF OBSERVERS INGRID BLUMTHALER AND JOCHEN TRUMPF

    E-Print Network [OSTI]

    Trumpf, Jochen

    by inspection. 1. Problem formulation. We study plants (observed systems) of the form P = w1 w2 w3 Fw1+w order, matrix) differential operators and the plant P is a linear time-invariant continuous time system is that the signal module F is an injective cogenerator in the category of D-modules, cf. [1]. Following the ideas

  1. OBSERVATIONS ON THE WEB AND BEHAVIOR OF WENDILGARDA SPIDERS

    E-Print Network [OSTI]

    Mathis, Wayne N.

    OBSERVATIONS ON THE WEB AND BEHAVIOR OF WENDILGARDA SPIDERS (ARANEAE: THERIDIOSOMATIDAE that theridiosomatids spin modified orb-webs, but only the web of the holarctic Theridiosoma gemmosum (C. L. Koch) has the unusual webs ofsome tropical theridio- somatid spiders that the senior author later identified

  2. Ensemble climate predictions using climate models and observational constraints

    E-Print Network [OSTI]

    REVIEW Ensemble climate predictions using climate models and observational constraints BY PETER A. STOTT 1,* AND CHRIS E. FOREST 2 1 Hadley Centre for Climate Change (Reading Unit), Meteorology Building, Massachusetts Institute of Technology, Cambridge, MA 02139, USA Two different approaches are described

  3. Identification of a mesoscale model with multiscale experimental observations

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Identification of a mesoscale model with multiscale experimental observations M.T. Nguyen, C and at mesoscale within the framework of a heterogeneous microstruc- ture which is modeled by a random elastic measurements of the displacement fields at macroscale and at mesoscale performed with only a single specimen

  4. Solar flare electron acceleration: comparing theories and observations

    E-Print Network [OSTI]

    Arnold O. Benz; Pascal Saint-Hilaire

    2003-08-19

    A popular scenario for electron acceleration in solar flares is transit-time damping of low-frequency MHD waves excited by reconnection and its outflows. The scenario requires several processes in sequence to yield energetic electrons of the observed large number. Until now there was very little evidence for this scenario, as it is even not clear where the flare energy is released. RHESSI measurements of bremsstrahlung by non-thermal flare electrons yield energy estimates as well as the position where the energy is deposited. Thus quantitative measurements can be put into the frame of the global magnetic field configuration as seen in coronal EUV line observations. We present RHESSI observations combined with TRACE data that suggest primary energy inputs mostly into electron acceleration and to a minor fraction into coronal heating and primary motion. The more sensitive and lower energy X-ray observations by RHESSI have found also small events (C class) at the time of the acceleration of electron beams exciting meter wave Type III bursts. However, not all RHESSI flares involve Type III radio emissions. The association of other decimeter radio emissions, such as narrowband spikes and pulsations, with X-rays is summarized in view of electron acceleration

  5. Observation of Beam ION Instability in Spear3

    SciTech Connect (OSTI)

    Teytelman, D.; /Dimtel, Redwood City; Cai, Y.; Corbett, W.J.; Raubenheimer, T.O.; Safranek, J.A.; Schmerge, J.F.; Sebek, J.J.; Wang, L.; /SLAC

    2011-12-14

    Weak vertical coupled bunch instability with oscillation amplitude at {mu}m level has been observed in SPEAR3. The instability becomes stronger when there is a vacuum pressure rise by partially turning off vacuum pumps and it becomes weaker when the vertical beam emittance is increased by turning off the skew quadrupole magnets. These confirmed that the instability was driven by ions in the vacuum. The threshold of the beam ion instability when running with a single bunch train is just under 200 mA. This paper presents the comprehensive observations of the beam ion instability in SPEAR3. The effects of vacuum pressure, beam current, beam filling pattern, chromaticity, beam emittance and bunch-by-bunch feedback are investigated in great detail. In an electron accelerator, ions generated from the residual gas molecules can be trapped by the beam. Then these trapped ions interact resonantly with the beam and cause beam instability and emittance blow-up. Most existing light sources use a long single bunch train filling pattern, followed by a long gap to avoid multi-turn ion trapping. However, such a gap does not preclude ions from accumulating during one passage of the single bunch train beam, and those ions can still cause a Fast Ion Instability (FII) as predicted by Raubenheimer and Zimmermann. FII has been observed in ALS, and PLS by artificially increasing the vacuum pressure by injecting helium gas into the vacuum chamber or by turning off the ion pumps in order to observe the beam ion instability. In some existing rings, for instance B factory, the beam ion instability was observed at the beginning of the machine operation after a long period of shutdown and then it automatically disappeared when the vacuum was better. However, when the beam emittance becomes smaller, the FII can occur at nominal conditions as observed in PLS, SOLEIL and SSRF. This paper reports the observations of beam ion instabilities in SPEAR3 under different condition during a period of one year, which includes single bunch train instability (FII) and multi-bunch train instability. Note that the instability may be not the same even with the same beam due to the change of the vacuum with time. SPEAR3 has a circumference of 234 m with a harmonic number of 372. SPEAR3 runs with six bunch train filling pattern in order to suppress the possible beam ion instability. Table 1 lists the main parameters of SPEAR3. The vacuum of SPEAR3 ranges from 0.1 to 0.5 nTorr, which varies from section to section.

  6. Observational testing of magnetospheric magnetic field models at geosynchronous orbit

    SciTech Connect (OSTI)

    Weiss, L.A.; Thomsen, M.F.; Reeves, G.D.; McComas, D.J.

    1996-09-01

    Empirical mode which estimate the magnetic field direction and magnitude at any point within the magnetosphere under a variety of conditions play an important role in space weather forecasting. We report here on a number of different studies aimed at quantitatively evaluating these models, and in particular the Tsyganenko T89a model. The models are evaluated in two basic ways: (1) by comparing the range of magnetic field tilt angles observed at geosynchronous orbit with the ranges predicted for the same locations by the models; and (2) by comparing the observed magnetic field mapping between the ionosphere and geosynchronous orbit (using two-satellite magnetic field conjunctions) with the model predictions at the same locations. We find that while the T89a model predicts reasonably well the basic variation in tilt angle with local time and permits a range of field inclinations adequate to encompass the majority of observed angles on the dawn, dusk, and night sides, it is unable to reproduce the range of inclinations on the dayside. The model also predicts a smaller magnetic latitude range of geosynchronous field line footpoints than the observed two-satellite mapping indicate. Together, these results suggest that the next generation of field models should allow a greater range of stretching, especially in local time sectors away from midnight. It is important to note, however, that any increased range should encompass less-stretched configurations: although there are certainly cases where the models are not sufficiently stretched, we find that on average all magnetic field models tested, including T89a, are too stretched. Finally, in investigating how well the observed degree of field stretch was ordered by various magnetospheric indices, we find that the tilt of the field at geosynchronous orbit is a promising candidate for the incorporation into future models.

  7. Generalized Uncertainty Principle and Recent Cosmic Inflation Observations

    E-Print Network [OSTI]

    Abdel Nasser Tawfik; Abdel Magied Diab

    2014-10-29

    The recent background imaging of cosmic extragalactic polarization (BICEP2) observations are believed as an evidence for the cosmic inflation. BICEP2 provided a first direct evidence for the inflation, determined its energy scale and debriefed witnesses for the quantum gravitational processes. The ratio of scalar-to-tensor fluctuations $r$ which is the canonical measurement of the gravitational waves, was estimated as $r=0.2_{-0.05}^{+0.07}$. Apparently, this value agrees well with the upper bound value corresponding to PLANCK $r\\leq 0.012$ and to WMAP9 experiment $r=0.2$. It is believed that the existence of a minimal length is one of the greatest predictions leading to modifications in the Heisenberg uncertainty principle or a GUP at the Planck scale. In the present work, we investigate the possibility of interpreting recent BICEP2 observations through quantum gravity or GUP. We estimate the slow-roll parameters, the tensorial and the scalar density fluctuations which are characterized by the scalar field $\\phi$. Taking into account the background (matter and radiation) energy density, $\\phi$ is assumed to interact with the gravity and with itself. We first review the Friedmann-Lemaitre-Robertson-Walker (FLRW) Universe and then suggest modification in the Friedmann equation due to GUP. By using a single potential for a chaotic inflation model, various inflationary parameters are estimated and compared with the PLANCK and BICEP2 observations. While GUP is conjectured to break down the expansion of the early Universe (Hubble parameter and scale factor), two inflation potentials based on certain minimal supersymmetric extension of the standard model result in $r$ and spectral index matching well with the observations. Corresponding to BICEP2 observations, our estimation for $r$ depends on the inflation potential and the scalar field. A power-law inflation potential does not.

  8. Finding Patterns in Behavioral Observations by Automatically Labeling Forms of Wikiwork in Barnstars

    E-Print Network [OSTI]

    McDonald, David W.

    Finding Patterns in Behavioral Observations by Automatically Labeling Forms of Wikiwork everyday behavioral observations to develop tools that could improve understanding and sense making behavioral observations; observations that people make of those around them. In a large online community

  9. Observed HR diagrams and stellar evolution: the interplay between observational constraints and theory ASP Conference Series, Vol. ???, 2001

    E-Print Network [OSTI]

    Przybilla, Norbert

    . Introduction Carbon, nitrogen and oxygen are the main catalysts for nuclear fusion in massive stars. While: Observational Constraints of Massive Star Evolution Norbert Przybilla UniversitË?atssternwarte, ScheinerstraÃ?e 1 the sum of CNO remains constant, the initial abundance ratios of these elements are altered by fusion

  10. On O($a^2$) effects in gradient flow observables

    E-Print Network [OSTI]

    Alberto Ramos; Stefan Sint

    2015-04-18

    In lattice gauge theories, the gradient flow has been used extensively both, for scale setting and for defining finite volume renormalization schemes for the gauge coupling. Unfortunately, rather large cutoff effects have been observed in some cases. We here investigate these effects to leading order in perturbation theory, considering various definitions of the lattice observable, the lattice flow equation and the Yang Mills lattice action. These considerations suggest an improved set- up for which we perform a scaling test in the pure SU(3) gauge theory, demonstrating strongly reduced cutoff effects. We then attempt to obtain a more complete understanding of the structure of O($a^2$) effects by applying Symanzik's effective theory approach to the 4+1 dimensional local field theory with flow time as the fifth dimension. From these considerations we are led to a fully O($a^2$) improved set-up the study of which is left to future work.

  11. HIGH SPATIAL RESOLUTION OBSERVATIONS OF LOOPS IN THE SOLAR CORONA

    SciTech Connect (OSTI)

    Brooks, David H.; Ugarte-Urra, Ignacio [College of Science, George Mason University, 4400 University Drive, Fairfax, VA 22030 (United States); Warren, Harry P. [Space Science Division, Naval Research Laboratory, Washington, DC 20375 (United States); Winebarger, Amy R. [NASA Marshall Space Flight Center, ZP 13, Huntsville, AL 35812 (United States)

    2013-08-01

    Understanding how the solar corona is structured is of fundamental importance to determine how the Sun's upper atmosphere is heated to high temperatures. Recent spectroscopic studies have suggested that an instrument with a spatial resolution of 200 km or better is necessary to resolve coronal loops. The High Resolution Coronal Imager (Hi-C) achieved this performance on a rocket flight in 2012 July. We use Hi-C data to measure the Gaussian widths of 91 loops observed in the solar corona and find a distribution that peaks at about 270 km. We also use Atmospheric Imaging Assembly data for a subset of these loops and find temperature distributions that are generally very narrow. These observations provide further evidence that loops in the solar corona are often structured at a scale of several hundred kilometers, well above the spatial scale of many proposed physical mechanisms.

  12. Optical SETI Observations of the Anomalous Star KIC 8462852

    E-Print Network [OSTI]

    Schuetz, Marlin; Shostak, Seth; Richards, Jon

    2015-01-01

    To explore the hypothesis that KIC 8462852's aperiodic dimming is caused by artificial megastructures in orbit (Wright et al. 2015), rather than a natural cause such as cometary fragments in a highly elliptical orbit (Marengo et al. 2015), we searched for electromagnetic signals from KIC 8462852 indicative of extraterrestrial intelligence. The primary observations were in the visible optical regime using the Boquete Optical SETI Observatory in Panama. In addition, as a preparatory exercise for the possible future detection of a candidate signal (Heidmann 1991), three of six observing runs simultaneously searched radio frequencies at the Allen Telescope Array in California. No periodic optical signals greater than 67 photons/m2 within a time frame of 25 ns were seen. This limit corresponds to isotropic optical pulses of 8E22 joules. If, however, any inhabitants of KIC 8462852 were targeting our solar system (Shostak & Villard 2004), the required energy would be reduced greatly. The limits on narrowband rad...

  13. Observation of the Goos-Haenchen Shift with Neutrons

    SciTech Connect (OSTI)

    Haan, Victor-O. de; Plomp, Jeroen; Rekveldt, Theo M.; Kraan, Wicher H.; Well, Ad A. van; Dalgliesh, Robert M.; Langridge, Sean

    2010-01-08

    The Goos-Haenchen effect is a spatial shift along an interface resulting from an interference effect that occurs for total internal reflection. This phenomenon was suggested by Sir Isaac Newton, but it was not until 1947 that the effect was experimentally observed by Goos and Haenchen. We provide the first direct, absolute, experimental determination of the Goos-Haenchen shift for a particle experiencing a potential well as required by quantum mechanics: namely, wave-particle duality. Here, the particle is a spin-polarized neutron reflecting from a film of magnetized material. We detect the effect through a subtle change in polarization of the neutron. Here, we demonstrate, through experiment and theory, that neutrons do exhibit the Goos-Haenchen effect and postulate that the associated time shift should also be observable.

  14. Separating weak lensing and intrinsic alignments using radio observations

    E-Print Network [OSTI]

    Whittaker, Lee; Battye, Richard A

    2015-01-01

    We discuss methods for performing weak lensing using radio observations to recover information about the intrinsic structural properties of the source galaxies. Radio surveys provide unique information that can benefit weak lensing studies, such as HI emission, which may be used to construct galaxy velocity maps, and polarized synchrotron radiation; both of which provide information about the unlensed galaxy and can be used to reduce galaxy shape noise and the contribution of intrinsic alignments. Using a proxy for the intrinsic position angle of an observed galaxy, we develop techniques for cleanly separating weak gravitational lensing signals from intrinsic alignment contamination in forthcoming radio surveys. Random errors on the intrinsic orientation estimates introduce biases into the shear and intrinsic alignment estimates. However, we show that these biases can be corrected for if the error distribution is accurately known. We demonstrate our methods using simulations, where we reconstruct the shear an...

  15. Observing the Rosensweig instability of a quantum ferrofluid

    E-Print Network [OSTI]

    Kadau, Holger; Wenzel, Matthias; Wink, Clarissa; Maier, Thomas; Ferrier-Barbut, Igor; Pfau, Tilman

    2015-01-01

    Ferrofluids show unusual hydrodynamic effects due to the magnetic nature of their constituents. For increasing magnetization a classical ferrofluid undergoes a Rosensweig instability and creates self-organized ordered surface structures or droplet crystals. A Bose-Einstein condensate with strong dipolar interactions is a quantum ferrofluid that also shows superfluidity. The field of dipolar quantum gases is motivated by the search for new phases that break continuous symmetries. The simultaneous breaking of continuous symmetries like the phase invariance for the superfluid state and the translational symmetry for a crystal provides the basis of novel states of matter. However, interaction-induced crystallization in a superfluid has not been observed. Here we use in situ imaging to directly observe the spontaneous transition from an unstructured superfluid to an ordered arrangement of droplets in an atomic dysprosium Bose-Einstein condensate. By utilizing a Feshbach resonance to control the interparticle inter...

  16. Mass flows in a prominence spine as observed in EUV

    SciTech Connect (OSTI)

    Kucera, T. A.; Gilbert, H. R.

    2014-07-20

    We analyze a quiescent prominence observed by the Solar Dynamics Observatory's Atmospheric Imaging Assembly (AIA) with a focus on mass and energy flux in the spine, measured using Lyman continuum absorption. This is the first time this type of analysis has been applied with an emphasis on individual features and fluxes in a quiescent prominence. The prominence, observed on 2010 September 28, is detectable in most AIA wavebands in absorption and/or emission. Flows along the spine exhibit horizontal bands 5''-10'' wide and kinetic energy fluxes on the order of a few times 10{sup 5} erg s{sup –1}cm{sup –2}, consistent with quiet sun coronal heating estimates. For a discrete moving feature we estimate a mass of a few times 10{sup 11} g. We discuss the implications of our derived properties for a model of prominence dynamics, the thermal non-equilibrium model.

  17. Near Infrared observations of Soft X-ray selected AGN

    E-Print Network [OSTI]

    D. Grupe; H. -C Thomas

    2002-02-21

    We report the results of near infrared observations of 19 soft X-ray selected AGN. The goal of the observations was to search for strong, narrow Paschen-alpha or Brackett-gamma emission lines, as a sign of nuclear starbursts. We found Pa-alpha emission in the spectra of 11 sources and Br-gamma in at least five. Strong NIR emission has been found in two sources, CBS 126 and Mkn 766, both objects with strong [OIII]5007 emission, weak FeII emission and wavelength dependent degree of polarization in the optical. Classical Narrow Line Seyfert 1 galaxies do not show exceptionally strong NIR emission lines. We present the results of our study and discuss how our findings fit into an evolutionary scheme of AGN.

  18. Accreting X-ray millisecond pulsars observed with INTEGRAL

    E-Print Network [OSTI]

    Maurizio Falanga

    2007-11-07

    I review the properties of three X-ray accreting millisecond pulsars observed with INTEGRAL. Out of seven recently discovered accretion-powered pulsars (one discovered by INTEGRAL), three were observed with the INTEGRAL satellite up to 300 keV. Detailed timing and spectral results will be presented, including data obtained during the most recent outburst of the pulsar HETE J1900.1-2455. Accreting X-ray millisecond pulsars are key systems to understand the spin and accretion history of neutron stars. They are also a good laboratory in which to study the source spectra, pulse profile, and phase shift between X-ray pulses in different energy ranges which give additional information of the X-ray production processes and emission environment.

  19. Experimental observation of precursor solitons in a flowing complex plasma

    E-Print Network [OSTI]

    Jaiswal, Surabhi; Sen, A

    2015-01-01

    The excitation of precursor solitons ahead of a rapidly moving object in a fluid, a spectacular phenomenon in hydrodynamics that has often been observed ahead of moving ships, has surprisingly not been investigated in plasmas where the fluid model holds good for low frequency excitations such as ion acoustic waves. In this paper we report the first experimental observation of precursor solitons in a flowing dusty plasma. The nonlinear solitary dust acoustic waves (DAWs) are excited by a supersonic mass flow of the dust particles over an electrostatic potential hill. In a frame where the fluid is stationary and the hill is moving the solitons propagate in the upstream direction as precursors while wake structures consisting of linear DAWs are seen to propagate in the downstream region. A theoretical explanation of these excitations based on the forced Korteweg-deVries model equation is provided and their practical implications in situations involving a charged object moving in a plasma are discussed.

  20. Observations and modelling of Helium lines in solar flares

    E-Print Network [OSTI]

    Simões, Paulo J A; Labrosse, Nicolas; Kerr, Graham S

    2015-01-01

    We explore the response of the He II 304 {\\AA} and He I 584 {\\AA} line intensities to electron beam heating in solar flares using radiative hydrodynamic simulations. Comparing different electron beams parameters, we found that the intensities of both He lines are very sensitive to the energy flux deposited in the chromosphere, or more specifically to the heating rate, with He II 304 {\\AA} being more sensitive to the heating than He I 584 {\\AA}. Therefore, the He line ratio increases for larger heating rates in the chromosphere. A similar trend is found in observations, using SDO/EVE He irradiance ratios and estimates of the electron beam energy rate obtained from hard X-ray data. From the simulations, we also found that spectral index of the electrons can affect the He ratio but a similar effect was not found in the observations.

  1. Observation of the Decay B??Ds(*)+K?l????l

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

    del Amo Sanchez, P.; Lees, J. P.; Poireau, V.; Prencipe, E.; Tisserand, V.; Garra Tico, J.; Grauges, E.; Martinelli, M.; Palano, A.; Pappagallo, M.; et al

    2011-07-22

    We report the observation of the decay B??Ds(*)+K?l??¯l based on 342fb?¹ of data collected at the ?(4S) resonance with the BABAR detector at the PEP-II e?e? storage rings at SLAC. A simultaneous fit to three D+s decay chains is performed to extract the signal yield from measurements of the squared missing mass in the B meson decay. We observe the decay B??Ds(*)+K?l??¯l with a significance greater than 5 standard deviations (including systematic uncertainties) and measure its branching fraction to be B(B??Ds(*)+K?l??¯l)=[6.13+1.04-1.03(stat)±0.43(syst)±0.51(B(Ds))]×10??, where the last error reflects the limited knowledge of the Ds branching fractions.

  2. Satellite observations of thought experiments close to a black hole

    E-Print Network [OSTI]

    S. K. Chakrabarti

    2000-07-18

    Since black holes are `black', methods of their identification must necessarily be indirect. Due to very special boundary condition on the horizon, the advective flow behaves in a particular way, which includes formation of centrifugal pressure dominated boundary layer or CENBOL where much of the infall energy is released and outflows are generated. The observational aspects of black holes must depend on the steady and time-dependent properties of this boundary layer. Several observational results are written down in this review which seem to support the predictions of thought experiments based on this advective accretion/outflow model. In future, when gravitational waves are detected, some other predictions of this model could be tested as well.

  3. Observational constraints on the curvaton model of inflation

    E-Print Network [OSTI]

    Christopher Gordon; Antony Lewis

    2003-04-26

    Simple curvaton models can generate a mixture of of correlated primordial adiabatic and isocurvature perturbations. The baryon and cold dark matter isocurvature modes differ only by an observationally null mode in which the two perturbations almost exactly compensate, and therefore have proportional effects at linear order. We discuss the CMB anisotropy in general mixed models, and give a simple approximate analytic result for the large scale CMB anisotropy. Working numerically we use the latest WMAP observations and a variety of other data to constrain the curvaton model. We find that models with an isocurvature contribution are not favored relative to simple purely adiabatic models. However a significant primordial totally correlated baryon isocurvature perturbation is not ruled out. Certain classes of curvaton model are thereby ruled out, other classes predict enough non-Gaussianity to be detectable by the Planck satellite. In the appendices we review the relevant equations in the covariant formulation and give series solutions for the radiation dominated era.

  4. Low Frequency Observations of a Head-Tail Radio Source

    E-Print Network [OSTI]

    Dharam Vir Lal; A. Pramesh Rao

    2004-06-28

    We have mapped the head-tail radio galaxy, 3C 129 at 240 and 610 MHz using the GMRT and studied the detailed morphology and spectral index variations in this object. This is the first attempt to observe a sample of head-tail sources at low frequencies. We find weak spectral steepening as we go away from the head along the jet. The Crosspiece has a spectral index of 0.9 (S$_{\

  5. Observable Gravitational Waves From Kinetically Modified Non-Minimal Inflation

    E-Print Network [OSTI]

    C. Pallis

    2015-10-08

    We consider Supersymmetric (SUSY) and non-SUSY models of chaotic inflation based on the simplest power-law potential with exponents n=2 and 4. We propose a convenient non-minimal coupling to gravity and a non-minimal kinetic term which ensure, mainly for n=4, inflationary observables favored by the BICEP2/Keck Array and Planck results. Inflation can be attained for subplanckian inflaton values with the corresponding effective theories retaining the perturbative unitarity up to the Planck scale.

  6. Observable Gravitational Waves From Kinetically Modified Non-Minimal Inflation

    E-Print Network [OSTI]

    Pallis, C

    2015-01-01

    We consider Supersymmetric (SUSY) and non-SUSY models of chaotic inflation based on the simplest power-law potential with exponents n=2 and 4. We propose a convenient non-minimal coupling to gravity and a non-minimal kinetic term which ensure, mainly for n=4, inflationary observables favored by the BICEP2/Keck Array and Planck results. Inflation can be attained for subplanckian inflaton values with the corresponding effective theories retaining the perturbative unitarity up to the Planck scale.

  7. Radio observations of the $?$-ray blazar 0528+134

    E-Print Network [OSTI]

    M. Pohl; W. Reich; T. P. Krichbaum; K. Standke; S. Britzen; H. P. Reuter; P. Reich; R. Schlickeiser; H. Ungerechts; R. L. Fiedler; E. B. Waltman; K. J. Johnston; F. D. Ghigo

    1995-12-20

    We report multifrequency observations of the $\\gamma$-ray blazar 0528+134 with the Effelsberg 100-m telescope, the IRAM 30-m telescope, and the NRL Green Bank Interferometer. 0528+134 underwent a major radio and mm outburst in 1993 a few month after a very strong outburst in high energy $\\gamma$-rays. A similar behaviour is indicated for the weaker $\\gamma$-ray outburst in May 1991 and the mm activity in the beginning of 1992. This result fits nicely to the general finding that blazars are bright in $\\gamma$-rays preferrentially at the beginning of a radio outburst. 0528+134 was observed with a global VLBI array at 22$\\,$GHz in November 1992. Within the IRIS-S and EUROPE geodetic VLBI observing campaigns the source was also observed regularly at 8.4$\\,$GHz. A new VLBI component which is not present in data at 22 $\\,$GHz from 1991 also exhibits superluminal motion. Backextra\\-polating in time we find that the new component was expelled from the core in the first half of 1991, near the first $\\gamma$-ray outburst in Mai 1991. Newest VLBI data indicate the appearance of another new component in 1994. Although this new component has yet been found only at two epochs, it appears to move superluminally and may have been expelled from the core between fall 1992 and summer 1993, i.e. near the time of the second gamma ray outburst and at the beginning of a strong radio outburst.

  8. FILAMENTARY STAR FORMATION: OBSERVING THE EVOLUTION TOWARD FLATTENED ENVELOPES

    SciTech Connect (OSTI)

    Lee, Katherine; Looney, Leslie; Johnstone, Doug; Tobin, John E-mail: lwl@illinois.edu E-mail: jtobin@nrao.edu

    2012-12-20

    Filamentary structures are ubiquitous from large-scale molecular clouds (a few parsecs) to small-scale circumstellar envelopes around Class 0 sources ({approx}1000 AU to {approx}0.1 pc). In particular, recent observations with the Herschel Space Observatory emphasize the importance of large-scale filaments (a few parsecs) and star formation. The small-scale flattened envelopes around Class 0 sources are reminiscent of the large-scale filaments. We propose an observationally derived scenario for filamentary star formation that describes the evolution of filaments as part of the process for formation of cores and circumstellar envelopes. If such a scenario is correct, small-scale filamentary structures (0.1 pc in length) with higher densities embedded in starless cores should exist, although to date almost all the interferometers have failed to observe such structures. We perform synthetic observations of filaments at the prestellar stage by modeling the known Class 0 flattened envelope in L1157 using both the Combined Array for Research in Millimeter-wave Astronomy (CARMA) and the Atacama Large Millimeter/Submillimeter Array (ALMA). We show that with reasonable estimates for the column density through the flattened envelope, the CARMA D array at 3 mm wavelengths is not able to detect such filamentary structure, so previous studies would not have detected them. However, the substructures may be detected with the CARMA D+E array at 3 mm and the CARMA E array at 1 mm as a result of more appropriate resolution and sensitivity. ALMA is also capable of detecting the substructures and showing the structures in detail compared to the CARMA results with its unprecedented sensitivity. Such detection will confirm the new proposed paradigm of non-spherical star formation.

  9. Radio Observations of Masers in Post-AGB Stars

    E-Print Network [OSTI]

    R. M. Deacon; A. J. Green; J. M. Chapman

    2003-10-02

    We present observations of 86 post-Asymptotic Giant Branch (post-AGB) stars of OH maser transitions, taken with the Parkes Telescope between September 2002 and August 2003. Post-AGB stars are the precursors of planetary nebulae, which have a wide range of morphologies that are not well explained. By studying the circumstellar envelopes of post-AGB stars through the masers produced in them, we hope to shed light on the origin of planetary nebula morphologies.

  10. Local thermal observables in spatially open FRW spaces

    E-Print Network [OSTI]

    Slava Emelyanov

    2014-10-27

    Certain local thermal observables are considered in well-known examples of spatially open FRW spaces: Milne, open de Sitter and anti de Sitter as well as Einstein static universes. Another value for fixing the ambiguity in defining the Wick square and, hence, the local temperature is motivated in the last example. Physical consequences of that choice are discussed for static and conformal vacua in those spaces.

  11. 2004: PUBLICATIONS WITH RESULTS FROM USERS' IRAM OBSERVATIONS

    E-Print Network [OSTI]

    RadioAstronomie Millimétrique, Institut de (IRAM)

    2004: PUBLICATIONS WITH RESULTS FROM USERS' IRAM OBSERVATIONS 1015. SULPHUR-BEARING SPECIES IN THE STAR FORMING REGION L1689N V. Wakelam, A. Castets, C. Ceccarelli, B. Lefloch, E. Caux, L. Pagani 2004.K. Jørgensen, M.R. Hogerheijde, E.F. van Dishoeck, G.A. Blake, F.L. Schöier 2004, A&A 413, 993 1017. COLD DUST

  12. How does pressure gravitate? Cosmological constant problem confronts observational cosmology

    SciTech Connect (OSTI)

    Narimani, Ali; Scott, Douglas; Afshordi, Niayesh E-mail: nafshordi@pitp.ca

    2014-08-01

    An important and long-standing puzzle in the history of modern physics is the gross inconsistency between theoretical expectations and cosmological observations of the vacuum energy density, by at least 60 orders of magnitude, otherwise known as the cosmological constant problem. A characteristic feature of vacuum energy is that it has a pressure with the same amplitude, but opposite sign to its energy density, while all the precision tests of General Relativity are either in vacuum, or for media with negligible pressure. Therefore, one may wonder whether an anomalous coupling to pressure might be responsible for decoupling vacuum from gravity. We test this possibility in the context of the Gravitational Aether proposal, using current cosmological observations, which probe the gravity of relativistic pressure in the radiation era. Interestingly, we find that the best fit for anomalous pressure coupling is about half-way between General Relativity (GR), and Gravitational Aether (GA), if we include Planck together with WMAP and BICEP2 polarization cosmic microwave background (CMB) observations. Taken at face value, this data combination excludes both GR and GA at around the 3 ? level. However, including higher resolution CMB observations (''highL'') or baryonic acoustic oscillations (BAO) pushes the best fit closer to GR, excluding the Gravitational Aether solution to the cosmological constant problem at the 4- 5 ? level. This constraint effectively places a limit on the anomalous coupling to pressure in the parametrized post-Newtonian (PPN) expansion, ?{sub 4} = 0.105 ± 0.049 (+highL CMB), or ?{sub 4} = 0.066 ± 0.039 (+BAO). These represent the most precise measurement of this parameter to date, indicating a mild tension with GR (for ?CDM including tensors, with 0?{sub 4}=), and also among different data sets.

  13. Algorithms, Protocols & Systems for Remote Observation Using Networked Robotic Cameras 

    E-Print Network [OSTI]

    Qin, Ni

    2010-01-16

    for the degree of DOCTOR OF PHILOSOPHY Approved by: Chair of Committee, Dezhen Song Committee Members, Ricardo Gutierrez-Osuna Dmitri Loguinov Ergun Akleman Head of Department, Valerie E. Taylor May 2008 Major Subject: Computer Science iii ABSTRACT Algorithms... in remote observation using networked robotic cameras. v To my lovely cat Maomao, my dear family Yu and Amy, and my parents vi ACKNOWLEDGMENTS I would like to thank my committee chair, Dr. Dezhen Song, and my committee members, Dr. Gutierrez-Osuna, Dr...

  14. New beryllium observations in low-metallicity stars

    E-Print Network [OSTI]

    P. Molaro; P. Bonifacio; F. Castelli; L. Pasquini

    1996-08-03

    We present observations of the Be II 313.0 nm resonance doublet in 14 halo and old disk stars with metallicities ranging from [Fe/H]=-0.4 to about -3.0 obtained with the CASPEC spectrograph of the ESO 3.6m telescope at a FWHM about 8.6 km/s resolution. Abundances are derived by means of the synthetic spectra technique employing Kurucz (1993) atmospheric models, with enhanced alpha-elements and no overshooting. The derived abundances together with those available in literature show that for -2.7 < [Fe/H] < -0.8 Be correlates linearly with iron [Be] proportional to 1.07(+/- 0.08)[Fe/H], giving strength to previous results. However, a steeper correlation is still possible at metallicities lower than [Fe/H]<-1.4 with [Be] proportional to 1.6(+/- 0.44)[Fe/H]. When iron is replaced with oxygen, Be is found tracking closely oxygen up to solar values, without signs of breaking in correspondence of the onset of the Galactic disk. No evidence of intrinsic dispersion is found, ought to the large errors involved in the Be abundance determinations, but for three stars (HD 106516, HD 3795, HD 211998) a significant upper limit in the Be abundance can be placed at about 1 dex below the mean trend of the Be-Fe relation. For such stars non conventional mixing is required to explain Be depletion. Be observations can be used to discriminate strongly Li-depleted stars. These are the stars which show less Li than that expected by high energy cosmic rays production as deduced from Be observations. The available Be observations imply that some of the stars which contribute to the scatter in the Li-Fe diagramme are Li-depleted stars.

  15. Evaluating climate models: Should we use weather or climate observations?

    SciTech Connect (OSTI)

    Oglesby, Robert J [ORNL; Erickson III, David J [ORNL

    2009-12-01

    Calling the numerical models that we use for simulations of climate change 'climate models' is a bit of a misnomer. These 'general circulation models' (GCMs, AKA global climate models) and their cousins the 'regional climate models' (RCMs) are actually physically-based weather simulators. That is, these models simulate, either globally or locally, daily weather patterns in response to some change in forcing or boundary condition. These simulated weather patterns are then aggregated into climate statistics, very much as we aggregate observations into 'real climate statistics'. Traditionally, the output of GCMs has been evaluated using climate statistics, as opposed to their ability to simulate realistic daily weather observations. At the coarse global scale this may be a reasonable approach, however, as RCM's downscale to increasingly higher resolutions, the conjunction between weather and climate becomes more problematic. We present results from a series of present-day climate simulations using the WRF ARW for domains that cover North America, much of Latin America, and South Asia. The basic domains are at a 12 km resolution, but several inner domains at 4 km have also been simulated. These include regions of complex topography in Mexico, Colombia, Peru, and Sri Lanka, as well as a region of low topography and fairly homogeneous land surface type (the U.S. Great Plains). Model evaluations are performed using standard climate analyses (e.g., reanalyses; NCDC data) but also using time series of daily station observations. Preliminary results suggest little difference in the assessment of long-term mean quantities, but the variability on seasonal and interannual timescales is better described. Furthermore, the value-added by using daily weather observations as an evaluation tool increases with the model resolution.

  16. Space based observations for monitoring extreme weather and climate events

    SciTech Connect (OSTI)

    Rao, P.K.

    1996-12-31

    Observations are essential for monitoring, understanding, and predicting the potential for extreme weather and climate events. These events occur on all time and spatial scales. Current NOAA operational satellites have a unique capability of providing many of the observations that are critical for monitoring these events. These observations and derived geophysical quantities can also be used for diagnostics and prediction purposes. Extreme weather conditions such as severe thunderstorms and flash floods, occur very quickly, may last for a short time, and create a considerable amount of damage. Advance warnings of the order of a few minutes are needed to alert the public so they may take adequate precautions. Some extreme weather conditions such as tropical storms (hurricanes) may last for days, and in order to predict the exact track, intensity of the storm and forecast the land fall, frequent observations are critical. Examples of satellite data that are obtained from the NOAA satellites are presented to demonstrate their ability to monitor the extreme weather phenomena. Examples of extreme climate conditions are droughts over continents and the annual depletion of ozone over the Antarctic. Data derived from NOAA satellites were used to monitor the severe drought over Texas and Southwestern U.S.A. in early 1996. Similar data are being used by other countries to monitor the drought in their regions. The development of the ozone hole over the Antarctic during the last fifteen years has been a major scientific and environmental concern. Data from NOAA operational satellites have been extensively used to show the yearly development and dissipation of the ozone hole during the Southern Hemisphere springtime.

  17. Covariance Analysis of Symmetry Energy Observables from Heavy Ion Collision

    E-Print Network [OSTI]

    Zhang, Yingxun; Li, Zhuxia

    2015-01-01

    Using covariance analysis, we quantify the correlations between the interaction parameters in a transport model and the observables commonly used to extract information of the Equation of State of Asymmetric Nuclear Matter in experiments. By simulating $^{124}$Sn+$^{124}$Sn, $^{124}$Sn+$^{112}$Sn and $^{112}$Sn+$^{112}$Sn reactions at beam energies of 50 and 120 MeV per nucleon, we have identified that the nucleon effective mass splitting are most strongly correlated to the neutrons and protons yield ratios with high kinetic energy from central collisions especially at high incident energy. The best observable to determine the slope of the symmetry energy, L, at saturation density is the isospin diffusion observable even though the correlation is not very strong ($\\sim$0.7). Similar magnitude of correlation but opposite in sign exists for isospin diffusion and nucleon isoscalar effective mass. At 120 MeV/u, the effective mass splitting and the isoscalar effective mass also have opposite correlation for the do...

  18. OBSERVATIONS OF THERMAL FLARE PLASMA WITH THE EUV VARIABILITY EXPERIMENT

    SciTech Connect (OSTI)

    Warren, Harry P.; Doschek, George A. [Space Science Division, Naval Research Laboratory, Washington, DC 20375 (United States); Mariska, John T. [School of Physics, Astronomy, and Computational Sciences, George Mason University, 4400 University Drive, Fairfax, VA 22030 (United States)

    2013-06-20

    One of the defining characteristics of a solar flare is the impulsive formation of very high temperature plasma. The properties of the thermal emission are not well understood, however, and the analysis of solar flare observations is often predicated on the assumption that the flare plasma is isothermal. The EUV Variability Experiment (EVE) on the Solar Dynamics Observatory provides spectrally resolved observations of emission lines that span a wide range of temperatures (e.g., Fe XV-Fe XXIV) and allow for thermal flare plasma to be studied in detail. In this paper we describe a method for computing the differential emission measure distribution in a flare using EVE observations and apply it to several representative events. We find that in all phases of the flare the differential emission measure distribution is broad. Comparisons of EVE spectra with calculations based on parameters derived from the Geostationary Operational Environmental Satellites soft X-ray fluxes indicate that the isothermal approximation is generally a poor representation of the thermal structure of a flare.

  19. Solar flare impulsive phase emission observed with SDO/EVE

    SciTech Connect (OSTI)

    Kennedy, Michael B.; Milligan, Ryan O.; Mathioudakis, Mihalis; Keenan, Francis P., E-mail: mkennedy29@qub.ac.uk [Astrophysics Research Centre, School of Mathematics and Physics, Queen's University Belfast, University Road, Belfast BT7 1NN (United Kingdom)

    2013-12-10

    Differential emission measures (DEMs) during the impulsive phase of solar flares were constructed using observations from the EUV Variability Experiment (EVE) and the Markov-Chain Monte Carlo method. Emission lines from ions formed over the temperature range log T{sub e} = 5.8-7.2 allow the evolution of the DEM to be studied over a wide temperature range at 10 s cadence. The technique was applied to several M- and X-class flares, where impulsive phase EUV emission is observable in the disk-integrated EVE spectra from emission lines formed up to 3-4 MK and we use spatially unresolved EVE observations to infer the thermal structure of the emitting region. For the nine events studied, the DEMs exhibited a two-component distribution during the impulsive phase, a low-temperature component with peak temperature of 1-2 MK, and a broad high-temperature component from 7 to 30 MK. A bimodal high-temperature component is also found for several events, with peaks at 8 and 25 MK during the impulsive phase. The origin of the emission was verified using Atmospheric Imaging Assembly images to be the flare ribbons and footpoints, indicating that the constructed DEMs represent the spatially average thermal structure of the chromospheric flare emission during the impulsive phase.

  20. Sgr A* Observations with H.E.S.S. II

    E-Print Network [OSTI]

    Parsons, R D; King, J; Lefranc, V; Moulin, E; Poon, H; Veh, J

    2015-01-01

    The Galactic Centre has been studied with the High Energy Stereoscopic System (H.E.S.S.) for over 10 years, revealing a bright, complex gamma-ray morphology. Besides a strong point-like very-high-energy gamma-ray source coincident with the supermassive black hole Sgr A*, pre- vious analyses also revealed a diffuse ridge of gamma-ray emission, indicative of a powerful cosmic-ray accelerator in this region. The addition of a fifth telescope with 600 m 2 mirror area to the centre of the H.E.S.S. array has increased the energy range accessible, allowing observations to take place down to 100 GeV and potentially below. This wider energy range allows an important overlap in observations with satellite instruments such as the Fermi-LAT gamma-ray telescope. We will present the results of new H.E.S.S observations of the Galactic Centre region and show a detailed analysis of the central source, including comparisons to results at other wavelengths.

  1. Observation of the $\\Xi_b^0$ Baryon

    SciTech Connect (OSTI)

    Aaltonen, T.; Alvarez Gonzalez, B.; Amerio, S.; Amidei, D.; Anastassov, A.; Annovi, A.; Antos, J.; Apollinari, G.; Appel, J.A.; Apresyan, A.; Arisawa, T.; /Waseda U. /Dubna, JINR

    2011-07-01

    The observation of the bottom, strange baryon {Xi}{sup 0}{sub b} through the decay chain {Xi}{sup 0}{sub b} {yields} {Xi}{sup +}{sub c} {pi}{sup -}, where {Xi}{sup +}{sub c} {yields} {Xi}{sup -} {pi}{sup +} {pi}{sup +}, {Xi}{sup -} {yields} {Lambda} {yields} p {pi}{sup -}, is reported using data corresponding to an integrated luminosity of 4.2 ft{sup -1} from p{anti p} collisions at {radical}{ovr s} = 1.96 TeV recorded with the Collider Detector at Fermilab. A signal of 25.3{sup +5.6}{sub -5.4} candidates is observed whose probability of arising from a background fluctuation is 3.6 x 10{sup -12}, corresponding to 6.8 Gaussian standard deviations. The {Xi}{sup 0}{sub b} mass is measured to be 5787.8 {+-} 5.0(stat) {+-} 1.3(syst) MeV/c{sup 2}. In addition, the {Xi}{sup -}{sub b} is observed through the process {Xi}{sup -}{sub b} {yields} {Xi}{sup 0}{sub c} {pi}{sup -}, where {Xi}{sup 0}{sub c} {yields} {Xi}{sup -} {pi}{sup +}, {Xi}{sup -} {yields} {Lambda} {pi}{sup -}, and {Lambda} {yields} p {pi}{sup -}.

  2. Characteristics of Magnetohydrodynamic Oscillations Observed with Michelson Doppler Imager

    E-Print Network [OSTI]

    Norton, A A; Bush, R I; Tarbell, T D

    1999-01-01

    We report on the spatial distribution of magnetogram oscillatory power and phase angles between velocity and magnetogram signals as observed with the Michelson Doppler Imager. The dataset is 151.25 arcsec times 151.25 arcsec containing sunspot from Dec 2, 1997 with a temporal sampling interval of 60 seconds and spatial sampling of 0.605 arcsec. Simultaneously observed continuum intensity and surface velocity accompany the magnetic information. We focus on three frequency regimes: 0.5-1.0, 3.0-3.5 and 5.5-6.0 mHz corresponding roughly to timescales of magnetic evolution, p-modes and the 3 minute resonant sunspot oscillation. Significant low frequency magnetogram power is found in lower flux pixels, 100-300 Gauss, in a striking ring with filamentary structure surrounding sunspot. Five minute magnetogram power peaks in extended regions of flux 600-800 Gauss. The 3 minute oscillation is observed in sunspot umbra in pixels whose flux measures 1300-1500 Gauss. Phase angles of approximately -90 degrees between veloc...

  3. Characteristics of Magnetohydrodynamic Oscillations Observed with Michelson Doppler Imager

    E-Print Network [OSTI]

    A. A. Norton; R. K. Ulrich; R. I. Bush; T. D. Tarbell

    1999-07-19

    We report on the spatial distribution of magnetogram oscillatory power and phase angles between velocity and magnetogram signals as observed with the Michelson Doppler Imager. The dataset is 151.25 arcsec times 151.25 arcsec containing sunspot from Dec 2, 1997 with a temporal sampling interval of 60 seconds and spatial sampling of 0.605 arcsec. Simultaneously observed continuum intensity and surface velocity accompany the magnetic information. We focus on three frequency regimes: 0.5-1.0, 3.0-3.5 and 5.5-6.0 mHz corresponding roughly to timescales of magnetic evolution, p-modes and the 3 minute resonant sunspot oscillation. Significant low frequency magnetogram power is found in lower flux pixels, 100-300 Gauss, in a striking ring with filamentary structure surrounding sunspot. Five minute magnetogram power peaks in extended regions of flux 600-800 Gauss. The 3 minute oscillation is observed in sunspot umbra in pixels whose flux measures 1300-1500 Gauss. Phase angles of approximately -90 degrees between velocity and magnetic flux in the 3.0-3.5 and 5.5-6.0 mHz regimes are found in regions of significant cross amplitude.

  4. Jet Induced Supernovae-Hydrodynamics and Observational Consequences

    E-Print Network [OSTI]

    A. Khokhlov; Peter Hoeflich

    2000-11-01

    Core collapse supernovae (SN) are the final stages of stellar evolution in massive stars during which the central region collapses, forms a neutron star (NS), and the outer layers are ejected. Recent explosion scenarios assumed that the ejection is due to energy deposition by neutrinos into the envelope but detailed models do not produce powerful explosions. There is mounting evidence for an asphericity in the SN which is difficult to explain within this picture. This evidence includes the observed high polarization, pulsar kicks, high velocity iron-group and intermediate-mass elements material observed in remnants, etc. The discovery of highly magnetars revived the idea that the basic mechanism for the ejection of the envelope is related to a highly focused MHD-jet formed at the NS. Our 3-D hydro simulations of the jet propagation through the star confirmed that the mechanism can explain the asphericities. In this paper, detailed 3-D models for jet induced explosions of "classical" core collapse supernovae are presented. We demonstrate the influence of the jet properties and of the underlaying progenitor structure on the final density and chemical structure. Finally, we discuss the observational consequences, predictions and tests of this scenario.

  5. First observations of tracking clouds using scanning ARM cloud radars

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

    Borque, Paloma; Giangrande, Scott; Kollias, Pavlos

    2014-12-01

    Tracking clouds using scanning cloud radars can help to document the temporal evolution of cloud properties well before large drop formation (‘‘first echo’’). These measurements complement cloud and precipitation tracking using geostationary satellites and weather radars. Here, two-dimensional (2-D) Along-Wind Range Height Indicator (AW-RHI) observations of a population of shallow cumuli (with and without precipitation) from the 35-GHz scanning ARM cloud radar (SACR) at the DOE Atmospheric Radiation Measurements (ARM) program Southern Great Plains (SGP) site are presented. Observations from the ARM SGP network of scanning precipitation radars are used to provide the larger scale context of the cloud fieldmore »and to highlight the advantages of the SACR to detect the numerous, small, non-precipitating cloud elements. A new Cloud Identification and Tracking Algorithm (CITA) is developed to track cloud elements. In CITA, a cloud element is identified as a region having a contiguous set of pixels exceeding a preset reflectivity and size threshold. The high temporal resolution of the SACR 2-D observations (30 sec) allows for an area superposition criteria algorithm to match cloud elements at consecutive times. Following CITA, the temporal evolution of cloud element properties (number, size, and maximum reflectivity) is presented. The vast majority of the designated elements during this cumulus event were short-lived non-precipitating clouds having an apparent life cycle shorter than 15 minutes. The advantages and disadvantages of cloud tracking using an SACR are discussed.« less

  6. HST/COS OBSERVATIONS OF THIRTEEN NEW He II QUASARS

    SciTech Connect (OSTI)

    Syphers, David; Anderson, Scott F.; Zheng Wei; Meiksin, Avery; Schneider, Donald P.; York, Donald G.

    2012-04-15

    The full reionization of intergalactic helium was a major event in the history of the intergalactic medium (IGM), and UV observations of the He II Gunn-Peterson trough allow us to characterize the end of this process at z {approx} 3. Due to intervening hydrogen absorption, quasars allowing such study are rare, with only 33 known in the literature, and most of those are very recent discoveries. We expand on our previous discovery work, and present 13 new He II quasars with redshifts 2.82 < z < 3.77, here selected with {approx}80% efficiency, and including several that are much brighter than the vast majority of those previously known. This is the largest sample of uniformly observed He II quasars covering such a broad redshift range, and they show evidence of IGM opacity increasing with redshift, as expected for the helium reionization epoch. No evidence of He II Ly{alpha} quasar emission is seen in individual or averaged spectra, posing a problem for standard models of the broad-line region. The current rapid advance in the study of He II quasars has been greatly facilitated by the Cosmic Origins Spectrograph on the Hubble Space Telescope, and we discuss the instrumental and other subtleties that must be taken into account in IGM He II observations.

  7. Utility of observational Hubble parameter data on dark energy evolution

    E-Print Network [OSTI]

    Meng, Xiao-Lei; Li, Shi-Yu; Zhang, Tong-Jie

    2015-01-01

    Aiming at exploring the nature of dark energy, we use thirty-six observational Hubble parameter data (OHD) in the redshift range $0 \\leqslant z \\leqslant 2.36$ to make a cosmological model-independent test of the two-point $Omh^2(z_{2};z_{1})$ diagnostic. In $\\Lambda$CDM, we have $Omh^2 \\equiv \\Omega_{m}h^2$, where $\\Omega_{m}$ is the matter density parameter at present. We bin all the OHD into four data points to mitigate the observational contaminations. By comparing with the value of $\\Omega_{m}h^2$ which is constrained tightly by the Planck observations, our results show that in all six testing pairs of $Omh^2$ there are two testing pairs are consistent with $\\Lambda$CDM at $1\\sigma$ confidence level (CL), whereas for another two of them $\\Lambda$CDM can only be accommodated at $2\\sigma$ CL. Particularly, for remaining two pairs, $\\Lambda$CDM is not compatible even at $2\\sigma$ CL. Therefore it is reasonable that although deviations from $\\Lambda$CDM exist for some pairs, cautiously, we cannot rule out th...

  8. First observations of tracking clouds using scanning ARM cloud radars

    SciTech Connect (OSTI)

    Borque, Paloma; Giangrande, Scott; Kollias, Pavlos

    2014-12-01

    Tracking clouds using scanning cloud radars can help to document the temporal evolution of cloud properties well before large drop formation (‘‘first echo’’). These measurements complement cloud and precipitation tracking using geostationary satellites and weather radars. Here, two-dimensional (2-D) Along-Wind Range Height Indicator (AW-RHI) observations of a population of shallow cumuli (with and without precipitation) from the 35-GHz scanning ARM cloud radar (SACR) at the DOE Atmospheric Radiation Measurements (ARM) program Southern Great Plains (SGP) site are presented. Observations from the ARM SGP network of scanning precipitation radars are used to provide the larger scale context of the cloud field and to highlight the advantages of the SACR to detect the numerous, small, non-precipitating cloud elements. A new Cloud Identification and Tracking Algorithm (CITA) is developed to track cloud elements. In CITA, a cloud element is identified as a region having a contiguous set of pixels exceeding a preset reflectivity and size threshold. The high temporal resolution of the SACR 2-D observations (30 sec) allows for an area superposition criteria algorithm to match cloud elements at consecutive times. Following CITA, the temporal evolution of cloud element properties (number, size, and maximum reflectivity) is presented. The vast majority of the designated elements during this cumulus event were short-lived non-precipitating clouds having an apparent life cycle shorter than 15 minutes. The advantages and disadvantages of cloud tracking using an SACR are discussed.

  9. Off-center observers versus supernovae in inhomogeneous pressure universes

    SciTech Connect (OSTI)

    Balcerzak, Adam; Dabrowski, Mariusz P.; Denkiewicz, Tomasz [Institute of Physics, University of Szczecin, Wielkopolska 15, 70-451 Szczecin (Poland)

    2014-09-10

    Exact luminosity distance and apparent magnitude formulae are applied to the Union2 557 supernovae sample in order to constrain the possible position of an observer outside of the center of symmetry in spherically symmetric inhomogeneous pressure Stephani universes, which are complementary to inhomogeneous density Lemaître-Tolman-Bondi (LTB) void models. Two specific models are investigated. The first allows a barotropic equation of state at the center of symmetry without the need to specify a scale factor function (model IIA). The second has no barotropic equation of state at the center, but has an explicit dust-like scale factor evolution (model IIB). It is shown that even at 3? CL, an off-center observer cannot be further than about 4.4 Gpc away from the center of symmetry, which is comparable to the reported size of a void in LTB models with the most likely value of the distance from the center at about 341 Mpc for model IIA and 68 Mpc for model IIB. The off-center observer cannot be farther away from the center than about 577 Mpc for model IIB at 3? CL. It is determined that the best-fit parameters which characterize inhomogeneity are ?{sub inh} = 0.77 (dimensionless: model IIA) and ? = 7.31 × 10{sup –9} (s km{sup –1}){sup 2/3} Mpc{sup –4/3} (model IIB).

  10. Covariance Analysis of Symmetry Energy Observables from Heavy Ion Collision

    E-Print Network [OSTI]

    Yingxun Zhang; M. B. Tsang; Zhuxia Li

    2015-07-24

    Using covariance analysis, we quantify the correlations between the interaction parameters in a transport model and the observables commonly used to extract information of the Equation of State of Asymmetric Nuclear Matter in experiments. By simulating $^{124}$Sn+$^{124}$Sn, $^{124}$Sn+$^{112}$Sn and $^{112}$Sn+$^{112}$Sn reactions at beam energies of 50 and 120 MeV per nucleon, we have identified that the nucleon effective mass splitting are most strongly correlated to the neutrons and protons yield ratios with high kinetic energy from central collisions especially at high incident energy. The best observable to determine the slope of the symmetry energy, L, at saturation density is the isospin diffusion observable even though the correlation is not very strong ($\\sim$0.7). Similar magnitude of correlation but opposite in sign exists for isospin diffusion and nucleon isoscalar effective mass. At 120 MeV/u, the effective mass splitting and the isoscalar effective mass also have opposite correlation for the double n/p and isoscaling p/p yield ratios. By combining data and simulations at different beam energies, it should be possible to place constraints on the slope of symmetry energy (L) and effective mass splitting with reasonable uncertainties.

  11. The Central Region in M100: Observations and Modeling

    E-Print Network [OSTI]

    J. H. Knapen; J. E. Beckman; C. H. Heller; I. Shlosman; R. S. de Jong

    1995-06-19

    We present new high-resolution observations of the center of the late-type spiral M100 (NGC 4321) supplemented by 3D numerical modeling of stellar and gas dynamics, including star formation (SF). NIR imaging has revealed a stellar bar, previously inferred from optical and 21 cm observations, and an ovally-shaped ring-like structure in the plane of the disk. The K isophotes become progressively elongated and skewed to the position angle of the bar (outside and inside the `ring') forming an inner bar-like region. The galaxy exhibits a circumnuclear starburst in the inner part of the K `ring'. Two maxima of the K emission have been observed to lie symmetrically with respect to the nucleus and equidistant from it slightly leading the stellar bar. We interpret the twists in the K isophotes as being indicative of the presence of a double inner Lindblad resonance (ILR) and test this hypothesis by modeling the gas flow in a self-consistent gas + stars disk embedded in a halo, with an overall NGC4321-like mass distribution. We have reproduced the basic morphology of the region (the bar, the large scale trailing shocks, two symmetric K peaks corresponding to gas compression maxima which lie at the caustic formed by the interaction of a pair of trailing and leading shocks in the vicinity of the inner ILR, both peaks being sites of SF, and two additional zones of SF corresponding to the gas compression maxima, referred usually as `twin peaks').

  12. VERITAS Observations of HESS J1943+213

    E-Print Network [OSTI]

    ,

    2015-01-01

    HESS J1943+213 is a very-high-energy (VHE; >100 GeV) gamma-ray point source detected during the H.E.S.S. Galactic Plane Survey. Radio, infrared, X-ray, and GeV gamma-ray counterparts have been identified for HESS J1943+213; however, the classification of the source is still uncertain. Recent publications have argued primarily in favor of an extreme BL Lac object behind the Galactic plane, though the scenario that HESS J1943+213 is a young pulsar wind nebula is viable as well. We present deep VERITAS observations of HESS J1943+213, which provide the most significant VHE detection of the source so far, with ~18 sigma excess. The source is detected at ~2% Crab Nebula flux above 200 GeV with VERITAS, with the source spectrum well fit by a power-law function and showing agreement with the H.E.S.S. detection. We also include results from analysis of Swift XRT observations contemporaneous with VERITAS. No significant flux or spectral variability is detected with VERITAS or Swift XRT observations. We place the VERITA...

  13. DRAMATIC CHANGE IN JUPITER'S GREAT RED SPOT FROM SPACECRAFT OBSERVATIONS

    SciTech Connect (OSTI)

    Simon, Amy A.; Wong, Michael H.; De Pater, Imke; Rogers, John H.; Orton, Glenn S.; Carlson, Robert W.; Asay-Davis, Xylar; Marcus, Philip S.

    2014-12-20

    Jupiter's Great Red Spot (GRS) is one of its most distinct and enduring features. Since the advent of modern telescopes, keen observers have noted its appearance and documented a change in shape from very oblong to oval, confirmed in measurements from spacecraft data. It currently spans the smallest latitude and longitude size ever recorded. Here we show that this change has been accompanied by an increase in cloud/haze reflectance as sensed in methane gas absorption bands, increased absorption at wavelengths shorter than 500 nm, and increased spectral slope between 500 and 630 nm. These changes occurred between 2012 and 2014, without a significant change in internal tangential wind speeds; the decreased size results in a 3.2 day horizontal cloud circulation period, shorter than previously observed. As the GRS has narrowed in latitude, it interacts less with the jets flanking its north and south edges, perhaps allowing for less cloud mixing and longer UV irradiation of cloud and aerosol particles. Given its long life and observational record, we expect that future modeling of the GRS's changes, in concert with laboratory flow experiments, will drive our understanding of vortex evolution and stability in a confined flow field crucial for comparison with other planetary atmospheres.

  14. Observation of incomplete fusion reactions at l < l {sub crit}

    SciTech Connect (OSTI)

    Yadav, Abhishek Sharma, Vijay R. Singh, Devendra P. Unnati,; Singh, B. P.; Prasad, R.; Singh, Pushpendra P.; Bala, Indu; Kumar, R.; Muralithar, S.; Singh, R. P.; Sharma, M. K.

    2014-08-14

    In order to understand the presence of incomplete fusion at low energies i.e. 4-7MeV/nucleon and also to study its dependence on various entrance-channel parameters, the two type of measurements (i) excitation function for {sup 12}C+{sup 159}Tb, and (ii) forward recoil ranges for {sup 12}C+{sup 159}Tb systems have been performed. The experimentally measured excitation functions have been analyzed within the framework of compound nucleus decay using statistical model code PACE4. Analysis of data suggests the production of xn/px)n-channels via complete fusion, as these are found to be well reproduced by PACE4 predictions, while, a significant enhancement in the excitation functions of ?-emitting channels has been observed over the theoretical ones, which has been attributed due to the incomplete fusion processes. Further, the incomplete fusion events observed in case of forward recoil range measurements have been explained on the basis of the breakup fusion model, where these events may be attributed to the fusion of {sup 8}Be and/or {sup 4}He from {sup 12}C projectile to the target nucleus. In the present work, the SUMRULE model calculations are found to highly underestimate the observed incomplete fusion cross-sections which indicate that the l-values lower than l {sub crit} (limit of complete fusion) significantly contribute to the incomplete fusion reactions.

  15. The Galactic cosmic-ray Sun shadow observed by HAWC

    E-Print Network [OSTI]

    Enriquez, O

    2015-01-01

    The magnetic field of the Solar corona is difficult to measure directly. However, indirect observations of the solar corona are possible using the deficit in flux of cosmic rays coming from the direction of the Sun. Low-energy cosmic rays (~GeV) are deflected by the inner magnetic field of the Sun and the interplanetary magnetic field frozen into the solar wind. In contrast, high-energy cosmic rays (~TeV and above) are absorbed in the Sun's photosphere producing a shadow in the Sun's nominal position viewed from Earth. Several ground-based instruments have observed the effects of the heliospheric magnetic field on the size of the sun shadow and its position. The High-Altitude Water Cherenkov Observatory (HAWC) is an air shower array located in the central region of Mexico that observes TeV cosmic rays at a rate of about 15 kHz. in this work, we present preliminary images of the sun shadow from data collected by HAWC during 2013 and 2014 for different energy ranges.

  16. Thermonuclear X-ray Bursts: Theory vs. Observations

    E-Print Network [OSTI]

    Andrew Cumming

    2003-11-18

    I review our theoretical understanding of thermonuclear flashes on accreting neutron stars, concentrating on comparisons to observations. Sequences of regular Type I X-ray bursts from GS 1826-24 and 4U 1820-30 are very well described by the theory. I discuss recent work which attempts to use the observed burst properties in these sources to constrain the composition of the accreted material. For GS 1826-24, variations in the burst energetics with accretion rate indicate that the accreted material has solar metallicity; for 4U 1820-30, future observations should constrain the hydrogen fraction, testing evolutionary models. I briefly discuss the global bursting behavior of burst sources, which continues to be a major puzzle. Finally, I turn to superbursts, which naturally fit into the picture as unstable carbon ignition in a thick layer of heavy elements. I present new time-dependent models of the cooling tails of superbursts, and discuss the various interactions between superbursts and normal Type I bursts, and what can be learned from them.

  17. 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.

  18. Saturn's aurora observed by the Cassini camera at visible wavelengths

    E-Print Network [OSTI]

    Dyudina, Ulyana A; Ewald, Shawn P; Wellington, Danika

    2015-01-01

    The first observations of Saturn's visible-wavelength aurora were made by the Cassini camera. The aurora was observed between 2006 and 2013 in the northern and southern hemispheres. The color of the aurora changes from pink at a few hundred km above the horizon to purple at 1000-1500 km above the horizon. The spectrum observed in 9 filters spanning wavelengths from 250 nm to 1000 nm has a prominent H-alpha line and roughly agrees with laboratory simulated auroras. Auroras in both hemispheres vary dramatically with longitude. Auroras form bright arcs between 70 and 80 degree latitude north and between 65 and 80 degree latitude south, which sometimes spiral around the pole, and sometimes form double arcs. A large 10,000-km-scale longitudinal brightness structure persists for more than 100 hours. This structure rotates approximately together with Saturn. On top of the large steady structure, the auroras brighten suddenly on the timescales of a few minutes. These brightenings repeat with a period of about 1 hour....

  19. Ulysses observations of magnetic waves due to newborn interstellar pickup ions. I. New observations and linear analysis

    SciTech Connect (OSTI)

    Cannon, Bradford E.; Smith, Charles W.; Isenberg, Philip A.; Vasquez, Bernard J.; Murphy, Neil; Nuno, Raquel G. E-mail: Charles.Smith@unh.edu E-mail: Bernie.Vasquez@unh.edu E-mail: raquel.nuno@asu.edu

    2014-04-01

    We have examined Ulysses magnetic field data using dynamic spectrogram techniques that compute wave amplitude, polarization, and direction of propagation over a broad range of frequencies and time. Events were identified that showed a strong polarization signature and an enhancement of power above the local proton gyrofrequency. We perform a statistical study of 502 wave events in an effort to determine when, where, and why they are observed. Most notably, we find that waves arising from newborn interstellar pickup ions are relatively rare and difficult to find. The quantities normally employed in theories of wave growth are neutral atom density and quantities related to their ionization and the subsequent dynamics such as wind speed, solar wind flux, and magnetic field orientation. We find the observations of waves to be largely uncorrelated to these quantities except for mean field direction where quasi-radial magnetic fields are favored and solar wind proton flux where wave observations appear to be favored by low flux conditions which runs contrary to theoretical expectations of wave generation. It would appear that an explanation based on source physics and instability growth rates alone is not adequate to account for the times when these waves are seen.

  20. Insights from modeling and observational evaluation of a precipitating continental cumulus event observed during the MC3E field campaign

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

    Mechem, David B.; Giangrande, Scott E.; Wittman, Carly S.; Borque, Paloma; Toto, Tami; Kollias, Pavlos

    2015-03-13

    A case of shallow cumulus and precipitating cumulus congestus sampled at the Atmospheric Radiation Measurement (ARM) Program Southern Great Plains (SGP) supersite is analyzed using a multi-sensor observational approach and numerical simulation. Observations from a new radar suite surrounding the facility are used to characterize the evolving statistical behavior of the precipitating cloud system. This is accomplished using distributions of different measures of cloud geometry and precipitation properties. Large-eddy simulation (LES) with size-resolved (bin) microphysics is employed to determine the forcings most important in producing the salient aspects of the cloud system captured in the radar observations. Our emphasis ismore »on assessing the importance of time-varying vs. steady-state large-scale forcing on the model's ability to reproduce the evolutionary behavior of the cloud system. Additional consideration is given to how the characteristic spatial scale and homogeneity of the forcing imposed on the simulation influences the evolution of cloud system properties. Results indicate that several new scanning radar estimates such as distributions of cloud top are useful to differentiate the value of time-varying (or at least temporally well-matched) forcing on LES solution fidelity.« less

  1. Deep z-band observations of the coolest Y dwarf

    SciTech Connect (OSTI)

    Kopytova, Taisiya G.; Crossfield, Ian J. M.; Deacon, Niall R.; Brandner, Wolfgang; Buenzli, Esther; Bayo, Amelia; Schlieder, Joshua E.; Manjavacas, Elena; Kopon, Derek; Biller, Beth A.

    2014-12-10

    WISE J085510.83-071442.5 (hereafter, WISE 0855-07) is the coolest Y dwarf known to date and is located at a distance of 2.31 ± 0.08 pc, giving it the fourth largest parallax of any known star or brown dwarf system. We report deep z-band observations of WISE 0855-07 using FORS2 on UT1/Very Large Telescope. We do not detect any counterpart to WISE 0855-07 in our z-band images and estimate a brightness upper limit of AB mag > 24.8 (F {sub ?} < 0.45 ?Jy) at 910 ± 65 nm with 3? confidence. We combine our z-band upper limit with previous near- and mid-infrared photometry to place constraints on the atmospheric properties of WISE 0855-07 via comparison to models which implement water clouds in the atmospheres of T {sub eff} < 300 K substellar objects. We find that none of the available models that implement water clouds can completely reproduce the observed spectral energy distribution of WISE 0855-07. Every model significantly disagrees with the (3.6 ?m/4.5 ?m) flux ratio and at least one other bandpass. Since methane is predicted to be the dominant absorber at 3-4 ?m, these mismatches might point to an incorrect or incomplete treatment of methane in current models. We conclude that (a) WISE0855-07 has T {sub eff} ? 200-250 K, (b) <80% of its surface is covered by clouds, and (c) deeper observations, and improved models of substellar evolution, atmospheres, clouds, and opacities will be necessary to better characterize this object.

  2. A comparison of observables for solid-solid phase transitions

    SciTech Connect (OSTI)

    Smilowitz, Laura B [Los Alamos National Laboratory; Henson, Bryan F [Los Alamos National Laboratory; Romero, Jerry J [Los Alamos National Laboratory

    2009-01-01

    The study of solid-solid phase transformations is hindered by the difficulty of finding a volumetric probe to use as a progress variable. Solids are typically optically opaque and heterogeneous. Over the past several years, second harmonic generation (SHG) has been used as a kinetic probe for a solid-solid phase transition in which the initial and final phases have different symmetries. Bulk generation of SHG is allowed by symmetry only in noncentrosymmetric crystallographic space groups. For the organic energetic nitramine octahydro-1,3 ,5,7 -tetranitro-1,3 ,5,7 -tatrazocine (HMX), the beta phase is centro symmetric (space group P2{sub 1}/c) and the delta phase iS noncentrosymmetric (space group P6{sub 1}22) making SHG an extremely sensitive, essentially zero background probe of the phase change progress. We have used SHG as a tool to follow the progress of the transformation from beta to delta phase during the solid-solid transformation. However, kinetic models of the transformation derived using different observables from several other groups have differed, showing later onset for the phase change and faster progression to completion. In this work, we have intercompared several techniques to understand these differences. The three techniques discussed are second harmonic generation, Raman spectroscopy, and differential scanning calorimetry (DSC). The progress of the beta to delta phase transition in HMX observed with each of these different probes will be discussed and advantages and disadvantages of each technique described. This paper compares several different observables for use in measuring the kinetics of solid-solid phase transitions. Relative advantages and disadvantages for each technique are described and a direct comparison of results is made for the beta to delta polymorphic phase transition of the energetic nitramine, octahydro-1,3,5,7-tetranitro-1,3,5,7-tatrazocine.

  3. INTERSTELLAR MAGNETIC FIELDS OBSERVED BY VOYAGER 1 BEYOND THE HELIOPAUSE

    SciTech Connect (OSTI)

    Burlaga, L. F. [NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States); Ness, N. F., E-mail: lburlagahsp@verizon.net, E-mail: nfnudel@yahoo.com [Institute for Astrophysics and Computational Sciences, Catholic University of America, Washington, DC 20064 (United States)

    2014-11-01

    Voyager 1 (V1) was beyond the heliopause between 2013.00 and 2014.41, where it was making in situ observations of the interstellar magnetic field (ISMF). The average azimuthal angle and elevation angle of the magnetic field B were (?) = 292.°5 ± 1.°4 and (?) = 22.°1 ± 1.°2, respectively. The angles ? and ? varied linearly at (1.°4 ± 0.°1) yr{sup –1} and (–1.°1 ± 0.°1) yr{sup –1}, respectively, suggesting that V1 was measuring the draped ISMF around the heliopause. The distributions of hourly averages of ? and ? were Gaussian distributions, with most probable values 292.°5 and 22.°1, and standard deviations (SDs) 1.°3 and 1.°1, respectively. The small SD indicates little or no turbulence transverse to B . An abrupt decrease in B from 0.50 nT on 2013/129.9 to 0.46 nT on 2013/130.6 was observed, possibly associated with a weak reverse shock or magnetoacoustic pressure wave following a burst of electron plasma oscillations. Between 2013/130.6 and 2013/365.3, (B) = 0.464 ± 0.009 nT, (?) = 292.°6 ± 0.°8, and (?) = 22.°1 ± 1.°1. The corresponding distribution of hourly averages of B was Gaussian with the most probable value 0.464 nT and ? = 0.009 nT. Since the uncertainty ? corresponds to the instrument and digitization noise, these observations provided an upper limit to the turbulence in the ISMF. The distributions of the hourly increments of B were Gaussian distributions with ? = 0.05 nT, 0.°4, and 0.°4, respectively, indicating that the V1 did not detect evidence of ''intermittent bursts'' of interstellar turbulence.

  4. Properties of galactic dark matter: Constraints from astronomical observations

    SciTech Connect (OSTI)

    Burch, B.; Cowsik, R.

    2013-12-10

    The distributions of normal matter and of dark matter in the Galaxy are coupled to each other as they both move in the common gravitational potential. In order to fully exploit this interplay and to derive the various properties of dark matter relevant to their direct and indirect detection, we have comprehensively reviewed the astronomical observations of the spatial and velocity distributions of the components of normal matter. We then postulate that the phase-space distribution of dark matter follows a lowered-isothermal form and self-consistently solve Poisson's equation to construct several models for the spatial and velocity distributions of dark matter. In this paper, we compute the total gravitational potential of the normal and dark matter components and investigate their consistency with current observations of the rotation curve of the Galaxy and of the spatial and velocity distributions of blue horizontal-branch and blue straggler stars. Even with this demand of consistency, a large number of models with a range of parameters characterizing the dark matter distribution remain. We find that the best choice of parameters, within the range of allowed values for the surface density of the disk 55 M {sub ?} pc{sup –2}, are the following: the dark matter density at the Galactic center ?{sub DM,} {sub c} ? 100-250 GeV cm{sup –3}, the local dark matter density ?{sub DM}(R {sub 0}) ? 0.56-0.72 GeV cm{sup –3}, and the rms speed of dark matter particles ?v{sub DM}{sup 2}(R{sub 0})?{sup 1/2}?490??550 km s{sup –1}. We also discuss possible astronomical observations that may further limit the range of the allowed models. The predictions of the allowed models for direct and indirect detection will be discussed separately in a companion paper.

  5. Heavy pollution suppresses light rain in China: observations and modeling

    SciTech Connect (OSTI)

    Qian, Yun; Gong, Daoyi; Fan, Jiwen; Leung, Lai R.; Bennartz, Ralph; Chen, Deliang; Wang, Weiguo

    2009-08-15

    Long-term observational data reveal that both the frequency and amount of light rain have decreased in eastern China (EC) for 1956-2005 with high spatial coherency. This is different from the trend of total rainfall observed in EC, which decreases in northern EC and increases in southern EC. To examine the cause of the light rain trends, we analyzed the long-term variability of atmospheric water vapor and its correlation with light rain events. Results show very weak relationships between large-scale moisture transport and light rain in EC. This suggests that light rain trend in EC is not driven by large-scale circulation changes. Because of human activities, pollutant emission has increased dramatically in China for the last few decades, leading to significant reductions in visibility between 1960 and 2000. Cloud-resolving model simulations show that aerosols corresponding to heavily polluted conditions can significantly increase the cloud droplet number concentration (CDNC) and reduce droplet sizes compared to pristine conditions. This can lead to a significant decline in raindrop concentration and delay raindrop formation because smaller cloud droplets are less efficient in the collision and coalescence processes. Together with weaker convection, the precipitation frequency and amount are significantly reduced in the polluted case. Satellite data also reveal higher CDNC and smaller droplet size over polluted land in EC relative to pristine regions, which is consistent with the model results. This evidence suggests that the significantly increased aerosol particles produced by air pollution are at least partly responsible for the decreased light rain events observed in China over the past fifty years.

  6. DETAILED MOLECULAR OBSERVATIONS TOWARD THE DOUBLE HELIX NEBULA

    SciTech Connect (OSTI)

    Torii, K.; Enokiya, R.; Hasegawa, K.; Kudo, N.; Fukui, Y.; Morris, M. R.

    2014-07-01

    The Double Helix Nebula (DHN), located 100 pc above Sgr A* in the Galactic center (GC), is a unique structure whose morphology suggests it is a magnetic feature. Recent molecular observations toward the DHN revealed two candidate molecular counterparts of the DHN at radial velocities of –35 km s{sup –1} and 0 km s{sup –1} and discussed the model in which the DHN has its origin at the circumnuclear disk in the GC. In this paper, new CO observations toward the DHN using the Caltech Submillimeter Observatory and Mopra telescopes are presented. The higher-resolution observations of ?1 pc scale reveal the detailed distributions and kinematics of the two CO counterparts (the 0 km s{sup –1} and –35 km s{sup –1} features) and provide new information on their physical conditions. As a result, we find that the 0 km s{sup –1} feature with a mass of 3.3 × 10{sup 4} M {sub ?} coincides with the infrared emission of the DHN, indicating clear association with the DHN. The association of the –35 km s{sup –1} feature, with a mass of 0.8 × 10{sup 4} M {sub ?}, is less clear compared with the 0 km s{sup –1} feature, but the complementary distribution between the molecular gas and the DHN and velocity variation along the DHN support its association with the DHN. The two molecular features are highly excited, as shown by the relatively high CO J = 2-1/J = 1-0 intensity ratios of ?1.0, and have kinetic temperatures of ?30 K, consistent with the typical molecular clouds in the GC.

  7. Observed hemispheric asymmetry in global sea ice changes

    SciTech Connect (OSTI)

    Cavalieri, D.J.; Gloersen, P.; Parkinson, C.L.; Comiso, J.C.; Zwally, H.J.

    1997-11-07

    From November 1978 through December 1996, the areal extent of sea ice decreased by 2.9 {+-} 0.4 percent decade in the Arctic and increased by 1.3 {+-} 0.2 percent per decade in the Antarctic. The observed hemispheric asymmetry in these trends is consistent with a modeled response to a carbon dioxide-induced climate warming. The interannual variations, which are 2.3 percent of the annual mean in the Arctic, with a predominant period of about 5 years, and 3.4 percent of the annual mean in the Antarctic, with a predominant period of about 3 years, are uncorrelated. 29 refs., 2 figs., 1 tab.

  8. Report on Physics of Channelization: Theory, Experiment, and Observation

    SciTech Connect (OSTI)

    Kudrolli, Arshad [Clark University] [Clark University

    2014-05-19

    The project involved a study of physical processes that create eroded channel and drainage networks. A particular focus was on how the shape of the channels and the network depended on the nature of the fluid flow. Our approach was to combine theoretical, experimental, and observational studies in close collaboration with Professor Daniel Rothman of the Massachusetts Institute of Technology. Laboratory -scaled experiments were developed and quantitative data on the shape of the pattern and erosion dynamics are obtained with a laser-aided topography technique and fluorescent optical imaging techniques.

  9. RADIO OBSERVATIONS OF HD 80606 NEAR PLANETARY PERIASTRON

    SciTech Connect (OSTI)

    Lazio, T. Joseph W.; Farrell, W. M.; Shankland, P. D.; Blank, D. L.

    2010-12-15

    This paper reports Very Large Array observations at 325 and 1425 MHz ({lambda}90 cm and {lambda}20 cm) during and near the periastron passage of HD 80606b on HJD 2454424.86 (2007 November 20). We obtain flux density limits (3{sigma}) of 1.7 mJy and 48 {mu}Jy at 325 and 1425 MHz, respectively, equivalent to planetary luminosity limits of 2.3 x 10{sup 24} erg s{sup -1} and 2.7 x 10{sup 23} erg s{sup -1}. Unfortunately, these are several orders of magnitude above the nominal Jovian value (at 40 MHz) of 2 x 10{sup 18} erg s{sup -1}. The motivation for these observations was that the planetary magnetospheric emission is driven by a stellar wind-planetary magnetosphere interaction so that the planetary luminosity would be elevated near periastron. We estimate that, near periastron, HD 80606b might be as much as 3000 times more luminous than Jupiter. Recent transit observations of HD 80606b provide reasonably stringent constraints on the planetary mass and radius, and, because of the planet's highly eccentric orbit, its rotation period is likely to be 'pseudo-synchronized' to its orbital period, allowing a robust estimate of the former. Consequently, we are able to make relatively robust estimates of the emission frequency of the planetary magnetospheric emission and find it to be around 60-90 MHz. While this is too low for our reported observations, we compare HD 80606b to other high-eccentricity systems and assess the detection possibilities for both near-term and more distant future systems. Of the known high-eccentricity planets, only HD 80606b is likely to be detectable, as the others (HD 20782B and HD 4113) are both lower mass and longer rotational periods, which imply weaker magnetic field strengths. We find that both the forthcoming 'EVLA low band' system, which will operate as low as 65 MHz, and the Low Frequency Array may be able to improve upon our planetary luminosity limits for HD 80606b, and do so at a more optimum frequency. If the low-frequency component of the Square Kilometre Array (SKA-lo) and a future lunar radio array are able to approach their thermal noise limits, they should be able to detect an HD 80606b-like planet, unless the amount by which the planet's luminosity increases is substantially less than the factor of 3000 that we estimate; for the SKA-lo, which is to be located in the southern hemisphere, future planetary surveys will have to find southern hemisphere equivalents of HD 80606b.

  10. ILLUMINATING THE DARKEST GAMMA-RAY BURSTS WITH RADIO OBSERVATIONS

    SciTech Connect (OSTI)

    Zauderer, B. A.; Berger, E.; Margutti, R.; Fong, W.; Laskar, T.; Chornock, R.; Soderberg, A. M. [Department of Astronomy, Harvard University, Cambridge, MA 02138 (United States); Levan, A. J. [Department of Physics, University of Warwick, Coventry CV4 7AL (United Kingdom); Olivares E, F.; Greiner, J. [Max-Planck-Institut fuer extraterrestrische Physik, Giessenbachstrasse, D-85748 Garching (Germany); Perley, D. A.; Horesh, A.; Carpenter, J. [Division of Physics, Mathematics and Astronomy, California Institute of Technology, Pasadena, CA 91225 (United States); Updike, A. C. [Department of Chemistry and Physics, Roger Williams University, Bristol, RI 02809 (United States); Tanvir, N. R. [Department of Physics and Astronomy, University of Leicester, Leicester LE1 7RH (United Kingdom); Menten, K. M. [Max-Planck-Institut fuer Radioastronomie, D-53121 Bonn (Germany); Nakar, E. [Department of Astrophysics, Sackler School of Physics and Astronomy, Tel Aviv University, 69978 Tel Aviv (Israel); Chandra, P. [National Centre for Radio Astrophysics, Tata Institute of Fundamental Research, Pune University Campus, Ganeshkhind, Pune 411007 (India); Castro-Tirado, A. J. [Instituto de Astrofisica de Andalucia (IAA-CSIC), P.O. Box 03004, E-18080 Granada (Spain); Bremer, M. [Institut de Radioastronomie Millimetrique, 300 rue de la Piscine, F-38406 Saint Martin d'Heres (France); and others

    2013-04-20

    We present X-ray, optical, near-infrared (IR), and radio observations of gamma-ray bursts (GRBs) 110709B and 111215A, as well as optical and near-IR observations of their host galaxies. The combination of X-ray detections and deep optical/near-IR limits establish both bursts as ''dark''. Sub-arcsecond positions enabled by radio detections lead to robust host galaxy associations, with optical detections that indicate z {approx}< 4 (110709B) and z Almost-Equal-To 1.8-2.9 (111215A). We therefore conclude that both bursts are dark due to substantial rest-frame extinction. Using the radio and X-ray data for each burst we find that GRB 110709B requires A{sub V}{sup host}{approx}>5.3 mag and GRB 111215A requires A{sub V}{sup host}{approx}>8.5 mag (assuming z = 2). These are among the largest extinction values inferred for dark bursts to date. The two bursts also exhibit large neutral hydrogen column densities of N{sub H,{sub int}} {approx}> 10{sup 22} cm{sup -2} (z = 2) as inferred from their X-ray spectra, in agreement with the trend for dark GRBs. Moreover, the inferred values are in agreement with the Galactic A{sub V} -N{sub H} relation, unlike the bulk of the GRB population. Finally, we find that for both bursts the afterglow emission is best explained by a collimated outflow with a total beaming-corrected energy of E{sub {gamma}} + E{sub K} Almost-Equal-To (7-9) Multiplication-Sign 10{sup 51} erg (z = 2) expanding into a wind medium with a high density, M Almost-Equal-To (6-20) Multiplication-Sign 10{sup -5} M{sub Sun} yr{sup -1} (n Almost-Equal-To 100-350 cm{sup -3} at Almost-Equal-To 10{sup 17} cm). While the energy release is typical of long GRBs, the inferred density may be indicative of larger mass-loss rates for GRB progenitors in dusty (and hence metal rich) environments. This study establishes the critical role of radio observations in demonstrating the origin and properties of dark GRBs. Observations with the JVLA and ALMA will provide a sample with sub-arcsecond positions and robust host associations that will help to shed light on obscured star formation and the role of metallicity in GRB progenitors.

  11. A third alternative to explain recent observations: Future deceleration

    E-Print Network [OSTI]

    Subenoy Chakraborty; Supriya Pan; Subhajit Saha

    2014-10-30

    In the present work we discuss a third alternative to explain the latest observational data concerning the accelerating Universe and its different stages. The particle creation mechanism in the framework of non-equilibrium thermodynamics is considered as a basic cosmic mechanism acting on the flat FRW geometry. By assuming that the gravitationally induced particle production occurs under "adiabatic" conditions, the deceleration parameter is expressed in terms of the particle creation rate which is chosen as a truncated power series of the Hubble parameter. The model shows the evolution of the Universe starting from inflation to the present late time acceleration and it also predicts future decelerating stage.

  12. Research Program towards Observation of Neutrino-Nucleus Coherent Scattering

    E-Print Network [OSTI]

    Henry T. Wong

    2006-09-15

    The article describes the research program pursued by the TEXONO Collaboration towards an experiment to observe coherent scattering between neutrinos and the nucleus at the power reactor. The motivations of studying this process are surveyed. In particular, a threshold of 100-200 eV has been achieved with an ultra-low-energy germanium detector prototype. This detection capability at low energy can also be adapted to conduct searches of Cold Dark Matter in the low-mass region as well as to enhance the sensitivities in the study of neutrino magnetic moments.

  13. Neutral hydrogen observations of spiral and irregular galaxies

    E-Print Network [OSTI]

    Reakes, Michael

    1980-05-01

    ACE The observations described in this dissertation were made at t.he Mullard Radio Astronomy Observatory, and the data reduce~ and analysed at the Cavendish l,aboratory. The work was carried out between October 1975 and November 1978. P-l Most... , Dr John Shake shaft , and also Mr Peter Warner and Dr John Baldwin for their guidance throughout the three years .. P-2 Except where specifically stated in the text the work presented in this dissertation is my own, and has not been carried out...

  14. LOCALIZED PLASMA DENSITY ENHANCEMENTS OBSERVED IN STEREO COR1

    SciTech Connect (OSTI)

    Jones, Shaela I.; Davila, Joseph M.

    2009-08-20

    Measurements of solar wind speed in the solar corona, where it is primarily accelerated, have proven elusive. One of the more successful attempts has been the tracking of outward-moving density inhomogeneities in white-light coronagraph images. These inhomogeneities, or 'blobs', have been treated as passive tracers of the ambient solar wind. Here we report on the extension of these observations to lower altitudes using the STEREO COR1 coronagraph, and discuss the implications of these measurements for theories about the origin of these features.

  15. The physics of Reionization: processes relevant for SKA observations

    E-Print Network [OSTI]

    Semelin, Benoit

    2015-01-01

    The local intensity of the 21 cm signal emitted during the Epoch of Reionization that will be mapped by the SKA is modulated by the amount of neutral hydrogen. Consequently, understanding the process of reionization of the intergalactic medium (IGM) is crucial for predicting and interpreting the upcoming observations. After presenting the basic physics and most meaningful quantities pertaining to the process of reionization, we will review recent progress in our understanding of the production and escape of ionizing photons in primordial galaxies and of their absorption in the IGM especially in so-called minihalos and Lyman Limit Systems.

  16. Strangeness suppression of qq¯ creation observed in exclusive reactions

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

    Mestayer, M. D.; Park, K.; Adhikari, K. P.; Aghasyan, M.; Pereira, S. Anefalos; Ball, J.; Battaglieri, M.; Batourine, V.; Bedlinskiy, I.; Biselli, A. S.; et al

    2014-10-10

    In this study, we measured the ratios of electroproduction cross sections from a proton target for three exclusive meson-baryon final states: ?K+, p?0, and n?+, with the CLAS detector at Jefferson Lab. Using a simple model of quark hadronization, we extract qq¯ creation probabilities for the first time in exclusive two-body production, in which only a single qq¯ pair is created. We observe a sizable suppression of strange quark-antiquark pairs compared to nonstrange pairs, similar to that seen in high-energy production.

  17. The Arctic Lower Troposphere Observed Structure (ALTOS) Campaign

    SciTech Connect (OSTI)

    Verlinde, J

    2010-10-18

    The ALTOS campaign focuses on operating a tethered observing system for routine in situ sampling of low-level (< 2 km) Arctic clouds. It has been a long-term hope to fly tethered systems at Barrow, Alaska, but it is clear that the Federal Aviation Administration (FAA) will not permit in-cloud tether systems at Barrow, even if unmanned aerial vehicle (UAV) operations are allowed in the future. We have provided the scientific rationale for long-term, routine in situ measurements of cloud and aerosol properties in the Arctic. The existing restricted air space at Oliktok offers an opportunity to do so.

  18. Radio emission from Colliding-Wind Binaries: Observations and Models

    E-Print Network [OSTI]

    S. M. Dougherty; J. M. Pittard; E. P. O'Connor

    2005-10-18

    We have developed radiative transfer models of the radio emission from colliding-wind binaries (CWB) based on a hydrodynamical treatment of the wind-collision region (WCR). The archetype of CWB systems is the 7.9-yr period binary WR140, which exhibits dramatic variations at radio wavelengths. High-resolution radio observations of WR140 permit a determination of several system parameters, particularly orbit inclination and distance, that are essential for any models of this system. A model fit to data at orbital phase 0.9 is shown, and some short comings of our model described.

  19. Observation of a Macroscopically Quantum-Entangled Insulator

    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 wouldMass mapSpeeding access to scienceSpeedingLightweight MaterialsGas andofPhase inObservation

  20. Observation of a Macroscopically Quantum-Entangled Insulator

    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 wouldMass mapSpeeding access to scienceSpeedingLightweight MaterialsGas andofPhaseObservation of

  1. Observation of a Macroscopically Quantum-Entangled Insulator

    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 wouldMass mapSpeeding access to scienceSpeedingLightweight MaterialsGas andofPhaseObservation

  2. Observation of a Macroscopically Quantum-Entangled Insulator

    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 wouldMass mapSpeeding access to scienceSpeedingLightweight MaterialsGasObservation of a

  3. Observations of the Madden Julian Oscillation for Cloud Modeling Studies

    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 wouldMass mapSpeeding access to scienceSpeedingLightweight MaterialsGasObservation ofthe Madden

  4. Observed Aerosol Radiative Forcings: Comparison for Natural and Anthropogenic Sources

    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 wouldMass mapSpeeding access to scienceSpeedingLightweight MaterialsGasObservation oftheAerosol

  5. Observing the Sparks of Life | Photosynthetic Antenna Research Center

    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 wouldMass mapSpeeding access to scienceSpeedingLightweightand Simulated Cirrus CloudObserving

  6. Observation of a Macroscopically Quantum-Entangled Insulator

    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 Room NewsInformationJesseworkSURVEY UNIVERSEHowScientific andComplex Oak RidgeObservation of a

  7. BeppoSAX observations of GRO J1744-28

    E-Print Network [OSTI]

    Doroshenko, R; Doroshenko, V; Suleimanov, V; Piraino, S

    2015-01-01

    We present an analysis of BeppoSAX observations of the unique transient bursting X-ray pulsar GRO J1744-28. The observations took place in March 1997 during the decay phase of the outburst. We find that the persistent broadband X-ray continuum of the source is consistent with a cutoff power law typical for the accreting pulsars. We also detect the fluorescence iron line at 6.7 keV and an absorption feature at ~4.5 keV, which we interpret as a cyclotron line. The corresponding magnetic field strength in the line forming region is ~3.7 x 10^11 G. Neither line is detected in the spectra of the bursts. However, additional soft thermal component with kT ~2 keV was required to describe the burst spectrum. We briefly discuss the nature of this component and argue that among other possibilities it might be connected with thermonuclear flashes at the neutron star surface which accompany the accretion-powered bursts in the source.

  8. Small solar wind transients: Stereo-A observations in 2009

    SciTech Connect (OSTI)

    Yu, W.; Farrugia, C. J.; Galvin, A. B.; Simunac, K. D. C.; Popecki, M. A.; Lugaz, N.; Kilpua, E. K. J.; Moestl, C.; Luhmann, J. G.; Opitz, A.; Sauvaud, J.-A.

    2013-06-13

    Year 2009 was the last year of a long and pronounced solar activity minimum. In this year the solar wind in the inner heliosphere was for 90% of the time slow (< 450 km s{sup -1}) and with a weaker magnetic field strength compared to the previous solar minimum 1995-1996. We choose this year to present the results of a systematic search for small solar wind transients (STs) observed by the STEREO-Ahead (ST-A) probe. The data are from the PLASTIC and IMPACT instrument suites. By 'small' we mean a duration from {approx}1 to 12 hours. The parameters we search for to identify STs are (i) the total field strength, (ii) the rotation of the magnetic field vector, (iii) its smoothness, (iv) proton temperature, (v) proton beta, and (vi) Alfven Mach number. We find 45 examples. The STs have an average duration of {approx}4 hours. Ensemble averages of key quantities are: (i) maximum B = 7.01 nT; (ii) proton {beta}= 0.18; (iii) proton thermal speed = 20.8 km s{sup -1}; and (iv) Alfven Mach number = 6.13. No distinctive feature is found in the pitch angle distributions of suprathermal electrons. Our statistical results are compared with those of STs observed near Earth by Wind during 2009.

  9. Confronting DGP braneworld gravity with cosmico observations after Planck data

    SciTech Connect (OSTI)

    Xu, Lixin

    2014-02-01

    The normal branch of Dvali-Gabadadze-Porrati braneworld gravity with brane tension is confronted by the currently available cosmic observations from the geometrical and dynamical perspectives. On the geometrical side, the type Ia supernova as standard candle, the baryon acoustic oscillation as standard ruler and the cosmic microwave background measurement from the first released 15.5 months data were used to fix the background evolutions. On the dynamical side, the redshift space distortion data will be used to determine the evolution of the matter perturbation. Through a Markov chain Monte Carlo analysis, we found the dimensionless crossover scale ?{sub r{sub c}} = 1/(4H{sup 2}{sub 0}r{sup 2}{sub c}) = 0.00183{sub ?0.00183}{sup +0.000338} in a spatially flat normal branch of Dvali-Gabadadze-Porrati braneworld. This result suggests that the crossover scale r{sub c} should be around 12H{sup ?1}{sub 0} which is consistent with the previous result r{sub c} > 3H{sup ?1}{sub 0} and greater. It also implies that the five-dimensional gravity effect is weak to be observed in H{sup ?1}{sub 0} scale.

  10. Kepler observations of variability in B-type stars

    E-Print Network [OSTI]

    Balona, L A; De Cat, P; Handler, G; Gutierrez-Soto, J; Engelbrecht, C A; Frescura, F; Briquet, M; Cuypers, J; Daszynska-Daszkiewicz, J; Degroote, P; Dukes, R J; Garcia, R A; Green, E M; Heber, U; Kawaler, S D; Ostensen, R; Pricopi, D; Roxburgh, I; Salmon, S; Smith, M A; Suarez, J C; Suran, M; Szabo, R; Uytterhoeven, K; Christensen-Dalsgaard,; Kjeldsen, H; Caldwell, D A; Girouard, F R; Sanderfer, D T

    2011-01-01

    The analysis of the light curves of 48 B-type stars observed by Kepler is presented. Among these are 15 pulsating stars, all of which show low frequencies characteristic of SPB stars. Seven of these stars also show a few weak, isolated high frequencies and they could be considered as SPB/beta Cep hybrids. In all cases the frequency spectra are quite different from what is seen from ground-based observations. We suggest that this is because most of the low frequencies are modes of high degree which are predicted to be unstable in models of mid-B stars. We find that there are non-pulsating stars within the beta Cep and SPB instability strips. Apart from the pulsating stars, we can identify stars with frequency groupings similar to what is seen in Be stars but which are not Be stars. The origin of the groupings is not clear, but may be related to rotation. We find periodic variations in other stars which we attribute to proximity effects in binary systems or possibly rotational modulation. We find no evidence fo...

  11. Heating and cooling of coronal loops observed by SDO

    E-Print Network [OSTI]

    Li, Leping; Chen, Feng; Zhang, Jun

    2015-01-01

    Context: One of the most prominent processes suggested to heat the corona to well above 10^6 K builds on nanoflares, short bursts of energy dissipation. Aims: We compare observations to model predictions to test the validity of the nanoflare process. Methods: Using extreme UV data from AIA/SDO and HMI/SDO line-of-sight magnetograms we study the spatial and temporal evolution of a set of loops in active region AR 11850. Results: We find a transient brightening of loops in emission from Fe xviii forming at about 7.2 MK while at the same time these loops dim in emission from lower temperatures. This points to a fast heating of the loop that goes along with evaporation of material that we observe as apparent upward motions in the image sequence. After this initial phases lasting for some 10 min, the loops brighten in a sequence of AIA channels showing cooler and cooler plasma, indicating the cooling of the loops over a time scale of about one hour. A comparison to the predictions from a 1D loop model shows that t...

  12. Cold dark matter cosmology conflicts with fluid mechanics and observations

    E-Print Network [OSTI]

    Carl H. Gibson

    2006-10-23

    Cold dark matter hierarchical clustering (CDMHC) cosmology based on the Jeans 1902 criterion for gravitational instability gives predictions about the early universe contrary to fluid mechanics and observations. Jeans neglected viscosity, diffusivity, and turbulence: factors that determine gravitational structure formation and contradict small structures (CDM halos) forming from non-baryonic dark matter particle candidates. From hydro-gravitational-dynamics (HGD) cosmology, viscous-gravitational fragmentation produced supercluster (10^46 kg), cluster, and galaxy-mass (10^42 kg) clouds in the primordial plasma with the large fossil density turbulence (rho_o ~ 3x10-17 kg m-3) of the first fragmentation at 10^12 s, and a protogalaxy linear and spiral clump morphology reflecting maximum stretching near vortex lines of the plasma turbulence at the 10^13 s plasma-gas transition. Gas protogalaxies fragmented into proto-globular-star-cluster mass (10^36 kg) clumps of protoplanet gas clouds that are now frozen as earth-mass (10^24-^25 kg) Jovian planets of the baryonic dark matter, about 30,000,000 rogue planets per star. Observations contradict the CDMHCC prediction of large explosive Population III first stars at 10^16 s, but support the immediate gentle formation of small Population II first stars at 10^13 s in globular-star-clusters from HGD.

  13. Observation of the Decay B- --> Ds(*) K- l- nubar

    SciTech Connect (OSTI)

    del Amo Sanchez, P.; Lees, J.P.; Poireau, V.; Prencipe, E.; Tisserand, V.; /Annecy, LAPP; Garra Tico, J.; Grauges, E.; /Barcelona U., ECM; Martinelli, M.; Palano, A.; Pappagallo, M.; /INFN, Bari /Bari U.; Eigen, G.; Stugu, B.; Sun, L.; /Bergen U.; Battaglia, M.; Brown, David Nathan; Hooberman, B.; Kerth, L.T.; Kolomensky, Yu.G.; Lynch, G.; Osipenkov, I.L.; Tanabe, T.; /UC, Berkeley /Birmingham U. /Ruhr U., Bochum /British Columbia U. /Brunel U. /Novosibirsk, IYF /UC, Irvine /UC, Riverside /UC, Santa Barbara /UC, Santa Cruz /Caltech /Cincinnati U. /Colorado U. /Colorado State U. /Dortmund U. /Dresden, Tech. U. /Ecole Polytechnique /Edinburgh U. /INFN, Ferrara /Ferrara U. /INFN, Ferrara /INFN, Ferrara /Ferrara U. /INFN, Ferrara /Frascati /INFN, Genoa /Genoa U. /INFN, Genoa /INFN, Genoa /Genoa U. /INFN, Genoa /INFN, Genoa /Genoa U. /Indian Inst. Tech., Guwahati /Harvard U. /Heidelberg U. /Humboldt U., Berlin /Imperial Coll., London /Iowa State U. /Iowa State U. /Johns Hopkins U. /Paris U., VI-VII /LLNL, Livermore /Liverpool U. /Queen Mary, U. of London /Royal Holloway, U. of London /Royal Holloway, U. of London /Louisville U. /Mainz U., Inst. Kernphys. /Manchester U. /Maryland U. /Massachusetts U., Amherst /MIT /McGill U.; /more authors..

    2011-08-12

    We report the observation of the decay B{sup -} {yields} D{sub s}{sup (*)+} K{sup -}{ell}{sup -}{bar {nu}}{sub {ell}} based on 342 fb{sup -1} of data collected at the {Upsilon}(4S) resonance with the BABAR detector at the PEP-II e{sup +}e{sup -} storage rings at SLAC. A simultaneous fit to three D{sub s}{sup +} decay chains is performed to extract the signal yield from measurements of the squared missing mass in the B meson decay. We observe the decay B{sup -} {yields} D{sub s}{sup (*)+} K{sup -}{ell}{sup -}{bar {nu}}{sub {ell}} with a significance greater than five standard deviations (including systematic uncertainties) and measure its branching fraction to be {Beta}(B{sup -} {yields} D{sub s}{sup (*)+} K{sup -}{ell}{sup -}{bar {nu}}{sub {ell}}) = [6.13{sub -1.03}{sup +1.04}(stat.) {+-} 0.43(syst.) {+-} 0.51({Beta}(D{sub s}))] x 10{sup -4}, where the last error reflects the limited knowledge of the D{sub s} branching fractions.

  14. CASSINI VIMS OBSERVATIONS SHOW ETHANE IS PRESENT IN TITAN'S RAINFALL

    SciTech Connect (OSTI)

    Dalba, Paul A.; Buratti, Bonnie J.; Baines, Kevin H.; Sotin, Christophe; Lawrence, Kenneth J.; Brown, Robert H.; Barnes, Jason W.; Clark, Roger N.; Nicholson, Philip D.

    2012-12-20

    Observations obtained over two years by the Cassini Imaging Science Subsystem suggest that rain showers fall on the surface. Using measurements obtained by the Visual Infrared Mapping Spectrometer, we identify the main component of the rain to be ethane, with methane as an additional component. We observe five or six probable rainfall events, at least one of which follows a brief equatorial cloud appearance, suggesting that frequent rainstorms occur on Titan. The rainfall evaporates, sublimates, or infiltrates on timescales of months, and in some cases it is associated with fluvial features but not with their creation or alteration. Thus, Titan exhibits frequent 'gentle rainfall' instead of, or in addition to, more catastrophic events that cut rivers and lay down large fluvial deposits. Freezing rain may also be present, and the standing liquid may exist as puddles interspersed with patches of frost. The extensive dune deposits found in the equatorial regions of Titan imply multi-season arid conditions there, which are consistent with small, but possibly frequent, amounts of rain, in analogy to terrestrial deserts.

  15. Stellar Populations and Surface Brightness Fluctuations: New Observations and Models

    E-Print Network [OSTI]

    John P. Blakeslee; Alexandre Vazdekis; Edward A. Ajhar

    2000-08-15

    We examine the use of surface brightness fluctuations (SBF) for both stellar population and distance studies. New V-band SBF data are reported for five Fornax cluster galaxies and combined with literature data to define a new V-band SBF distance indicator. We use new stellar population models, based on the latest Padua isochrones transformed empirically to the observational plane, to predict SBF magnitudes and integrated colours for a wide range of population ages and metallicities. We examine the sensitivity of the predictions to changes in the isochrones, transformations, and IMF. The new models reproduce the SBF data for globular clusters fairly well, especially if higher metallicity globulars are younger. The models also give a good match to the "fluctuation colors" of elliptical galaxies. In order to obtain theoretical calibrations of the SBF distance indicators, we combine our single-burst models into composite population models. These models reproduce the observed behavior of the SBF magnitudes as a function of stellar population parameters, including the steep colour dependence found for HST/WFPC2 F814W SBF data. Because the theoretical SBF calibrations are fairly sensitive to uncertain details of stellar evolution, the empirical calibrations are more secure. However, the sensitivity of SBF to these finer details potentially makes it a powerful constraint for stellar evolution and population synthesis. [abbridged

  16. VLA observations of the "water fountain" IRAS 16552-3050

    E-Print Network [OSTI]

    Olga Suárez; J. F. Gómez; L. F. Miranda

    2008-09-02

    We present Very Large Array (VLA) observations of the water maser emission towards IRAS 16552-3050. The maser emission shows a velocity spread of ~170 km/s, and a bipolar distribution with a separation between the red and blueshifted groups of ~0.08". These observations and the likely post-AGB nature of the source indicate that IRAS 16552-3050 can be considered as a member of the "water fountain" class of sources (evolved stars showing H2O maser emission with a velocity spread $\\ga$ 100 km/s, probably tracing collimated jets). The water maser emission in IRAS 16552-3050 does not seem to be associated with with any known optical counterpart. Moreover, this source does not have a near-IR 2MASS counterpart, as it happens in about half of the water fountains known. This suggests that these sources tend to be heavily obscured objects, probably with massive precursors ($\\ga 4-5$ M$_\\odot$). We suggest that the water maser emission in IRAS 16552-3050 could be tracing a rapidly precessing bipolar jet.

  17. Observations of hydroxyl in early-type galaxies

    E-Print Network [OSTI]

    McBride, James; Nyland, Kristina

    2014-01-01

    We used Arecibo Observatory and the Green Bank Telescope to observe OH in twelve early-type galaxies with known reservoirs of dense gas. We present three new detections of OH in absorption in the 1667 MHz line. One objective of our survey was to find evidence of molecular outflows, but our sensitivity, and the strength of the OH absorption, were insufficient to detect outflows. The detected sources have infrared luminosities and dust temperatures among the lowest of any galaxy detected in OH absorption. The ratio $L_{\\rm HCN} / L_{\\rm CO}$, a measure of the dense gas fraction in galaxies, is a powerful selector of OH megamasers for galaxies with high infrared luminosity. In early-type galaxies, which have much lower infrared luminosities, $L_{\\rm HCN} / L_{\\rm CO}$ is also a promising tool for discovering OH, but in absorption rather than in maser emission. In addition to dense molecular gas, a radio continuum source and a favorable line-of-sight to the observer are likely key factors in detecting OH absorber...

  18. Testing coupled dark energy with large scale structure observation

    SciTech Connect (OSTI)

    Yang, Weiqiang; Xu, Lixin, E-mail: d11102004@mail.dlut.edu.cn, E-mail: lxxu@dlut.edu.cn [Institute of Theoretical Physics, School of Physics and Optoelectronic Technology, Dalian University of Technology, Dalian, 116024 (China)

    2014-08-01

    The coupling between the dark components provides a new approach to mitigate the coincidence problem of cosmological standard model. In this paper, dark energy is treated as a fluid with a constant equation of state, whose coupling with dark matter is Q-bar =3H?{sub x}?-bar {sub x}. In the frame of dark energy, we derive the evolution equations for the density and velocity perturbations. According to the Markov Chain Monte Carlo method, we constrain the model by currently available cosmic observations which include cosmic microwave background radiation, baryon acoustic oscillation, type Ia supernovae, and f?{sub 8}(z) data points from redshift-space distortion. The results show the interaction rate in ? regions: ?{sub x} = 0.00328{sub -0.00328-0.00328-0.00328}{sup +0.000736+0.00549+0.00816}, which means that the recently cosmic observations favor a small interaction rate which is up to the order of 10{sup -2}, meanwhile, the measurement of redshift-space distortion could rule out the large interaction rate in the ? region.

  19. Formation of Double Neutron Star systems as implied by observations

    E-Print Network [OSTI]

    Beniamini, Paz

    2015-01-01

    Double Neutron Stars (DNS) have to survive two supernovae and still remain bound. This sets strong limits on the nature of the second collapse in these systems. We consider the masses and orbital parameters of the DNS population and constrain the two distributions of mass ejection and kick velocities directly from observations with no a-priori assumptions regarding evolutionary models and/or the types of the supernovae involved. We show that there is strong evidence for two distinct types of supernovae in these systems, where the second collapse in the majority of the observed systems involved small mass ejection ($\\Delta M\\lesssim 0.5M_{\\odot}$) and a corresponding low-kick velocity ($v_{k}\\lesssim 30 km/sec$). This formation scenario is compatible, for example, with an electron capture supernova. Only a minority of the systems have formed via the standard SN scenario involving larger mass ejection of $\\sim 2.2 M_{\\odot}$ and kick velocities of up to $400$km/sec. Due to the typically small kicks in most DNS ...

  20. An observational study of entrainment rate in deep convection

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

    Guo, Xiaohao; Lu, Chunsong; Zhao, Tianliang; Zhang, Guang Jun; Liu, Yangang

    2015-09-22

    This study estimates entrainment rate and investigates its relationships with cloud properties in 156 deep convective clouds based on in-situ aircraft observations during the TOGA-COARE (Tropical Ocean Global Atmosphere Coupled Ocean Atmosphere Response Experiment) field campaign over the western Pacific. To the authors’ knowledge, this is the first study on the probability density function of entrainment rate, the relationships between entrainment rate and cloud microphysics, and the effects of dry air sources on the calculated entrainment rate in deep convection from an observational perspective. Results show that the probability density function of entrainment rate can be well fitted by lognormal,more »gamma or Weibull distribution, with coefficients of determination being 0.82, 0.85 and 0.80, respectively. Entrainment tends to reduce temperature, water vapor content and moist static energy in cloud due to evaporative cooling and dilution. Inspection of the relationships between entrainment rate and microphysical properties reveals a negative correlation between volume-mean radius and entrainment rate, suggesting the potential dominance of homogeneous mechanism in the clouds examined. The entrainment rate and environmental water vapor content show similar tendencies of variation with the distance of the assumed environmental air to the cloud edges. Their variation tendencies are non-monotonic due to the relatively short distance between adjacent clouds.« less