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Sample records for warm dense matter

  1. Ultrafast Spectroscopy of Warm Dense Matter

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

    Ultrafast Spectroscopy of Warm Dense Matter Ultrafast Spectroscopy of Warm Dense Matter Print Wednesday, 25 April 2012 00:00 Being neither solid, liquid, gas, nor plasma, warm dense matter (WDM) occupies a no man's land in the map of material phases. Its temperature can range between that of planetary cores (tens of thousands K) to that of stellar cores (hundreds of thousands K). Not only is it prevalent throughout the universe, it is relevant to inertial confinement fusion (ICF) and material

  2. Electronic Structure of Warm Dense Matter via Multicenter Green...

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

    Electronic Structure of Warm Dense Matter via Multicenter Green's Function Technique Research Personnel Modeling The proposed research addresses the Warm Dense Matter area...

  3. Ultrafast Spectroscopy of Warm Dense Matter

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

    Spectroscopy of Warm Dense Matter Print Being neither solid, liquid, gas, nor plasma, warm dense matter (WDM) occupies a no man's land in the map of material phases. Its temperature can range between that of planetary cores (tens of thousands K) to that of stellar cores (hundreds of thousands K). Not only is it prevalent throughout the universe, it is relevant to inertial confinement fusion (ICF) and material performance under extreme conditions. However, because of its extreme temperatures and

  4. Ultrafast Spectroscopy of Warm Dense Matter

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

    Ultrafast Spectroscopy of Warm Dense Matter Print Being neither solid, liquid, gas, nor plasma, warm dense matter (WDM) occupies a no man's land in the map of material phases. Its temperature can range between that of planetary cores (tens of thousands K) to that of stellar cores (hundreds of thousands K). Not only is it prevalent throughout the universe, it is relevant to inertial confinement fusion (ICF) and material performance under extreme conditions. However, because of its extreme

  5. Ultrafast Spectroscopy of Warm Dense Matter

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

    Ultrafast Spectroscopy of Warm Dense Matter Print Being neither solid, liquid, gas, nor plasma, warm dense matter (WDM) occupies a no man's land in the map of material phases. Its temperature can range between that of planetary cores (tens of thousands K) to that of stellar cores (hundreds of thousands K). Not only is it prevalent throughout the universe, it is relevant to inertial confinement fusion (ICF) and material performance under extreme conditions. However, because of its extreme

  6. Electronic Structure of Warm Dense Matter via Multicenter Green's Function

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

    Technique | The Ames Laboratory Electronic Structure of Warm Dense Matter via Multicenter Green's Function Technique Research Personnel Publications Modeling The proposed research addresses the Warm Dense Matter area identified in the Report of the ReNeW in HEDLP. The electronic structure, equation of state, radiative, and transport properties of warm electrons in an amorphous or disordered configuration of ions are not well described by either solid state or plasma models. Such warm-dense

  7. Nuclear stopping power in warm and hot dense matter

    SciTech Connect (OSTI)

    Faussurier, Gerald; Blancard, Christophe; Gauthier, Maxence

    2013-01-15

    We present a method to estimate the nuclear component of the stopping power of ions propagating in dense matter. Three kinds of effective pair potentials are proposed. Results from the warm dense matter regime and the domain of high energy density physics are presented and discussed for proton and helium. The role of ionic temperature is examined. The nuclear stopping power can play a noticeable role in hot dense matter.

  8. Observations of Plasmons in Warm Dense Matter

    SciTech Connect (OSTI)

    Glenzer, S H; Landen, O L; Neumayer, P; Lee, R W; Widmann, K; Pollaine, S W; Wallace, R J; Gregori, G; Holl, A; Bornath, T; Thiele, R; Schwarz, V; Kraeft, W; Redmer, R

    2006-09-05

    We present the first collective x-ray scattering measurements of plasmons in solid-density plasmas. The forward scattering spectra of a laser-produced narrow-band x-ray line from isochorically heated beryllium show that the plasmon frequency is a sensitive measure of the electron density. Dynamic structure calculations that include collisions and detailed balance match the measured plasmon spectrum indicating that this technique will enable new applications to determine the equation of state and compressibility of dense matter.

  9. Experimental Studies of the Transport Parameters of Warm Dense Matter

    SciTech Connect (OSTI)

    Chouffani, Khalid

    2014-12-01

    There is a need to establish fundamental properties of matter and energy under extreme physical conditions. Although high energy density physics (HEDP) research spans a wide range of plasma conditions, there is one unifying regime that is of particular importance and complexity: that of warm dense matter, the transitional state between solid state condensed matter and energetic plasmas. Most laboratory experimental conditions, including inertial confinement implosion, fall into this regime. Because all aspects of laboratory-created high-energy-density plasmas transition through the warm dense matter regime, understanding the fundamental properties to determine how matter and energy interact in this regime is an important aspect of major research efforts in HEDP. Improved understanding of warm dense matter would have significant and wide-ranging impact on HEDP science, from helping to explain wire initiation studies on the Sandia Z machine to increasing the predictive power of inertial confinement fusion modeling. The central goal or objective of our proposed research is to experimentally determine the electrical resistivity, temperature, density, and average ionization state of a variety of materials in the warm dense matter regime, without the use of theoretical calculations. Since the lack of an accurate energy of state (EOS) model is primarily due to the lack of experimental data, we propose an experimental study of the transport coefficients of warm dense matter.

  10. Ultrafast Spectroscopy of Warm Dense Matter

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

    the properties of all. In disciplines such as condensed matter or plasma physics, one force often dominates over the others, allowing smaller forces to be neglected in physical...

  11. Predictions of x-ray scattering spectra in warm dense matter...

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

    Technical Report: Predictions of x-ray scattering spectra in warm dense matter Citation Details In-Document Search Title: Predictions of x-ray scattering spectra in warm dense ...

  12. Intense Ion Beam for Warm Dense Matter Physics

    SciTech Connect (OSTI)

    Coleman, Joshua Eugene

    2008-05-23

    The Neutralized Drift Compression Experiment (NDCX) at Lawrence Berkeley National Laboratory is exploring the physical limits of compression and focusing of ion beams for heating material to warm dense matter (WDM) and fusion ignition conditions. The NDCX is a beam transport experiment with several components at a scale comparable to an inertial fusion energy driver. The NDCX is an accelerator which consists of a low-emittance ion source, high-current injector, solenoid matching section, induction bunching module, beam neutralization section, and final focusing system. The principal objectives of the experiment are to control the beam envelope, demonstrate effective neutralization of the beam space-charge, control the velocity tilt on the beam, and understand defocusing effects, field imperfections, and limitations on peak intensity such as emittance and aberrations. Target heating experiments with space-charge dominated ion beams require simultaneous longitudinal bunching and transverse focusing. A four-solenoid lattice is used to tune the beam envelope to the necessary focusing conditions before entering the induction bunching module. The induction bunching module provides a head-to-tail velocity ramp necessary to achieve peak axial compression at the desired focal plane. Downstream of the induction gap a plasma column neutralizes the beam space charge so only emittance limits the focused beam intensity. We present results of beam transport through a solenoid matching section and simultaneous focusing of a singly charged K{sup +} ion bunch at an ion energy of 0.3 MeV. The results include a qualitative comparison of experimental and calculated results after the solenoid matching section, which include time resolved current density, transverse distributions, and phase-space of the beam at different diagnostic planes. Electron cloud and gas measurements in the solenoid lattice and in the vicinity of intercepting diagnostics are also presented. Finally, comparisons

  13. Linear dependence of surface expansion speed on initial plasma temperature in warm dense matter

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

    Bang, Woosuk; Albright, Brian James; Bradley, Paul Andrew; Vold, Erik Lehman; Boettger, Jonathan Carl; Fernández, Juan Carlos

    2016-07-12

    Recent progress in laser-driven quasi-monoenergetic ion beams enabled the production of uniformly heated warm dense matter. Matter heated rapidly with this technique is under extreme temperatures and pressures, and promptly expands outward. While the expansion speed of an ideal plasma is known to have a square-root dependence on temperature, computer simulations presented here show a linear dependence of expansion speed on initial plasma temperature in the warm dense matter regime. The expansion of uniformly heated 1–100 eV solid density gold foils was modeled with the RAGE radiation-hydrodynamics code, and the average surface expansion speed was found to increase linearly withmore » temperature. The origin of this linear dependence is explained by comparing predictions from the SESAME equation-of-state tables with those from the ideal gas equation-of-state. In conclusion, these simulations offer useful insight into the expansion of warm dense matter and motivate the application of optical shadowgraphy for temperature measurement.« less

  14. Ultrabright x-ray laser scattering for dynamic warm dense matter physics

    SciTech Connect (OSTI)

    Fletcher, L. B.; Lee, H. J.; Doppner, T.; Galtier, E.; Nagler, B.; Heimann, P.; Fortmann, C.; Mao, T.; Millot, M.; Pak, A.; Turnbull, D.; Chapman, D. A.; Gericke, D. O.; Vorberger, J.; White, T.; Gregori, G.; Wei, M.; Barbrel, B.; Falcone, R. W.; Kao, C. -C.; Nuhn, H.; Welch, J.; Zastrau, U.; Neumayer, P.; Hastings, J. B.; Glenzer, S. H.

    2015-03-23

    In megabar shock waves, materials compress and undergo a phase transition to a dense charged-particle system that is dominated by strong correlations and quantum effects. This complex state, known as warm dense matter, exists in planetary interiors and many laboratory experiments (for example, during high-power laser interactions with solids or the compression phase of inertial confinement fusion implosions). Here, we apply record peak brightness X-rays at the Linac Coherent Light Source to resolve ionic interactions at atomic (ångström) scale lengths and to determine their physical properties. Our in situ measurements characterize the compressed lattice and resolve the transition to warm dense matter, demonstrating that short-range repulsion between ions must be accounted for to obtain accurate structure factor and equation of state data. Additionally, the unique properties of the X-ray laser provide plasmon spectra that yield the temperature and density with unprecedented precision at micrometre-scale resolution in dynamic compression experiments.

  15. Comparison of electron transport calculations in warm dense matter using the Ziman formula

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

    Burrill, D. J.; Feinblum, D. V.; Charest, M. R. J.; Starrett, C. E.

    2016-02-10

    The Ziman formulation of electrical conductivity is tested in warm and hot dense matter using the pseudo-atom molecular dynamics method. Several implementation options that have been widely used in the literature are systematically tested through a comparison to the accurate, but expensive Kohn–Sham density functional theory molecular dynamics (KS-DFT-MD) calculations. As a result, the comparison is made for several elements and mixtures and for a wide range of temperatures and densities, and reveals a preferred method that generally gives very good agreement with the KS-DFT-MD results, but at a fraction of the computational cost.

  16. The viscosity to entropy ratio: From string theory motivated bounds to warm dense matter

    SciTech Connect (OSTI)

    Faussurier, G.; Libby, S. B.; Silvestrelli, P. L.

    2014-07-04

    Here, we study the ratio of viscosity to entropy density in Yukawa one-component plasmas as a function of coupling parameter at fixed screening, and in realistic warm dense matter models as a function of temperature at fixed density. In these two situations, the ratio is minimized for values of the coupling parameters that depend on screening, and for temperatures that in turn depend on density and material. In this context, we also examine Rosenfeld arguments relating transport coefficients to excess reduced entropy for Yukawa one-component plasmas. For these cases we show that this ratio is always above the lower-bound conjecture derived from string theory ideas.

  17. NDCX-II, A New Induction Linear Accelerator for Warm Dense Matter Research

    SciTech Connect (OSTI)

    Leitner, M.; Bieniosek, F.; Kwan, J.; Logan, G.; Waldron, W.; Barnard, J.J.; Friedman, A.; Sharp, B.; Gilson, E.; Davidson, R.

    2009-06-01

    The Heavy Ion Fusion Science Virtual National Laboratory (HIFS-VNL), a collaboration between Lawrence Berkeley National Laboratory (LBNL), Lawrence Livermore National Laboratory (LLNL), and Princeton Plasma Physics Laboratory (PPPL), is currently constructing a new induction linear accelerator, called Neutralized Drift Compression eXperiment NDCX-II. The accelerator design makes effective use of existing components from LLNL's decommissioned Advanced Test Accelerator (ATA), especially induction cells and Blumlein voltage sources that have been transferred to LBNL. We have developed an aggressive acceleration 'schedule' that compresses the emitted ion pulse from 500 ns to 1 ns in just 15 meters. In the nominal design concept, 30 nC of Li{sup +} are accelerated to 3.5 MeV and allowed to drift-compress to a peak current of about 30 A. That beam will be utilized for warm dense matter experiments investigating the interaction of ion beams with matter at high temperature and pressure. Construction of the accelerator will be complete within a period of approximately two and a half years and will provide a worldwide unique opportunity for ion-driven warm dense matter experiments as well as research related to novel beam manipulations for heavy ion fusion drivers.

  18. The viscosity to entropy ratio: From string theory motivated bounds to warm dense matter

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

    Faussurier, G.; Libby, S. B.; Silvestrelli, P. L.

    2014-07-04

    Here, we study the ratio of viscosity to entropy density in Yukawa one-component plasmas as a function of coupling parameter at fixed screening, and in realistic warm dense matter models as a function of temperature at fixed density. In these two situations, the ratio is minimized for values of the coupling parameters that depend on screening, and for temperatures that in turn depend on density and material. In this context, we also examine Rosenfeld arguments relating transport coefficients to excess reduced entropy for Yukawa one-component plasmas. For these cases we show that this ratio is always above the lower-bound conjecturemore » derived from string theory ideas.« less

  19. Short intense ion pulses for materials and warm dense matter research

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

    Seidl, Peter A.; Persaud, Arun; Waldron, William L.; Barnard, John J.; Davidson, Ronald C.; Friedman, Alex; Gilson, Erik P.; Greenway, Wayne G.; Grote, David P.; Kaganovich, Igor D.; et al

    2015-11-11

    We have commenced experiments with intense short pulses of ion beams on the Neutralized Drift Compression Experiment-II at Lawrence Berkeley National Laboratory, by generating beam spots size with radius r<1 mm within 2 ns FWHM and approximately 1010 ions/pulse. To enable the short pulse durations and mm-scale focal spot radii, the 1.2 MeV Li+ ion beam is neutralized in a 1.6-meter drift compression section located after the last accelerator magnet. An 8-Tesla short focal length solenoid compresses the beam in the presence of the large volume plasma near the end of this section before the target. The scientific topics tomore » be explored are warm dense matter, the dynamics of radiation damage in materials, and intense beam and beam-plasma physics including selected topics of relevance to the development of heavy-ion drivers for inertial fusion energy. Finally, we describe the accelerator commissioning and time-resolved ionoluminescence measurements of yttrium aluminum perovskite using the fully integrated accelerator and neutralized drift compression components.« less

  20. Short intense ion pulses for materials and warm dense matter research

    SciTech Connect (OSTI)

    Seidl, Peter A.; Persaud, Arun; Waldron, William L.; Barnard, John J.; Davidson, Ronald C.; Friedman, Alex; Gilson, Erik P.; Greenway, Wayne G.; Grote, David P.; Kaganovich, Igor D.; Lidia, Steven M.; Stettler, Matthew; Takakuwa, Jeffrey H.; Schenkel, Thomas

    2015-11-11

    We have commenced experiments with intense short pulses of ion beams on the Neutralized Drift Compression Experiment-II at Lawrence Berkeley National Laboratory, by generating beam spots size with radius r<1 mm within 2 ns FWHM and approximately 1010 ions/pulse. To enable the short pulse durations and mm-scale focal spot radii, the 1.2 MeV Li+ ion beam is neutralized in a 1.6-meter drift compression section located after the last accelerator magnet. An 8-Tesla short focal length solenoid compresses the beam in the presence of the large volume plasma near the end of this section before the target. The scientific topics to be explored are warm dense matter, the dynamics of radiation damage in materials, and intense beam and beam-plasma physics including selected topics of relevance to the development of heavy-ion drivers for inertial fusion energy. Finally, we describe the accelerator commissioning and time-resolved ionoluminescence measurements of yttrium aluminum perovskite using the fully integrated accelerator and neutralized drift compression components.

  1. Linear accelerator design study with direct plasma injection scheme for warm dense matter

    SciTech Connect (OSTI)

    Kondo, K.; Kanesue, T; Okamura, M.

    2011-03-28

    Warm Dense Matter (WDM) is a challenging science field, which is related to heavy ion inertial fusion and planetary science. It is difficult to expect the behavior because the state with high density and low temperature is completely different from ideal condition. The well-defined WDM generation is required to understand it. Moderate energy ion beams ({approx} MeV/u) slightly above Bragg peak is an advantageous method for WDM because of the uniform energy deposition. Direct Plasma Injection Scheme (DPIS) with a Interdigital H-mode (IH) accelerator has a potential for the beam parameter. We show feasible parameters of the IH accelerator for WDM. WDM physics is a challenging science and is strongly related to Heavy Ion Fusion science. WDM formation by Direct Plasma Injection Scheme (DPIS) with IH accelerator, which is a compact system, is proposed. Feasible parameters for IH accelerator are shown for WDM state. These represents that DPIS with IH accelerator can access a different parameter region of WDM.

  2. Visualizing expanding warm dense matter heated by laser-generated ion beams

    SciTech Connect (OSTI)

    Bang, Woosuk

    2015-08-24

    This PowerPoint presentation concluded with the following. We calculated the expected heating per atom and temperatures of various target materials using a Monte Carlo simulation code and SESAME EOS tables. We used aluminum ion beams to heat gold and diamond uniformly and isochorically. A streak camera imaged the expansion of warm dense gold (5.5 eV) and diamond (1.7 eV). GXI-X recorded all 16 x-ray images of the unheated gold bar targets proving that it could image the motion of the gold/diamond interface of the proposed target.

  3. A Unique U.S. Approach for Accelerator-Driven Warm Dense Matter Research--Preliminary Report

    SciTech Connect (OSTI)

    Logan, B G; Davidson, R C; Barnard, J J; Lee, R

    2004-12-22

    The warm density matter regime of high energy density physics [1, 2, 3] has a high scientific discovery potential for the properties of plasmas at high densities and pressures and at moderate temperatures (kT) in which the Coulomb interaction energy between plasma particles exceed kT. This leads to correlations in the plasma characterized by the dimensionless ''coupling'' parameter {Lambda} > 1, where {Lambda} is defined by {Lambda} = q{sup 2}n{sup 1/3}/kT. Here q is the effective ion charge and n the ion density. Strongly-coupled plasmas with {Lambda} > 1 are difficult to study analytically and by numerical simulation. Many astrophysical systems (e.g., brown dwarfs, and giant planets) and inertial fusion plasmas in the beginning stages of compression fall into this regime. There is an opportunity to develop improved understanding and models through accurate measurements of properties in the large parameter space of temperature and density where data is currently limited or non-existent. X-ray free-electron lasers (Fourth generation light sources), ultra-short pulse and high energy optical lasers, pulsed-power z-pinch x-ray sources, and high explosives are all capable of producing warm dense matter conditions at various temperatures, pressures, and sample sizes. Therefore, the challenge is not how to create warm dense matter conditions, but to create it so that it's fundamental properties can be best studied. The goal is to advance this field of science through a variety of complementary facilities and methods which offer several combinations of desirable attributes: Precise control and uniformity of energy deposition; Large sample sizes compared to diagnostic resolution volumes; A benign environment for diagnostics (low debris and radiation background); High shot rates (10/hour to 1/second) and multiple beamlines/target chambers; and Sites with easy access for broad participation by university scientists and students; and with the technical support for designing

  4. Demonstration of space-resolved x-ray Thomson scattering capability for warm dense matter experiments on the Z accelerator

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

    Ao, T.; Harding, E. C.; Bailey, J. E.; Lemke, R. W.; Desjarlais, M. P.; Hansen, S. B.; Smith, I. C.; Geissel, M.; Maurer, A.; Reneker, J.; et al

    2016-01-13

    Experiments on the Sandia Z pulsed-power accelerator demonstrated the ability to produce warm dense matter (WDM) states with unprecedented uniformity, duration, and size, which are ideal for investigations of fundamental WDM properties. For the first time, space-resolved x-ray Thomson scattering (XRTS) spectra from shocked carbon foams were recorded on Z. The large (> 20 MA) electrical current produced by Z was used to launch Al flyer plates up to 25 km/s. The impact of the flyer plate on a CH2 foam target produced a shocked state with an estimated pressure of 0.75 Mbar, density of 0.52 g/cm3, and temperature ofmore » 4.3 eV. Both unshocked and shocked portions of the foam target were probed with 6.2 keV x-rays produced by focusing the Z-Beamlet laser onto a nearby Mn foil. The data is composed of three spatially distinct spectra that were simultaneously captured with a single spectrometer with high spectral (4.8 eV) and spatial (190 μm) resolutions. Furthermore, these spectra provide detailed information on three target locations: the laser spot, the unshocked foam, and the shocked foam.« less

  5. Electron-ion temperature equilibration in warm dense tantalum

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

    Doppner, T; LePape, S.; Ma, T.; Pak, A.; Hartley, N. J.; Peters, L.; Gregori, G.; Belancourt, P.; Drake, R. P.; Chapman, D. A.; et al

    2014-11-05

    We present measurements of electron-ion temperature equilibration in proton-heated tantalum, under warm dense matter conditions. Our results agree with theoretical predictions for metals calculated using input data from ab initio simulations. Furthermore, the fast relaxation observed in the experiment contrasts with much longer equilibration times found in proton heated carbon, indicating that the energy flow pathways in warm dense matter are far from being fully understood.

  6. Equilibration dynamics and conductivity of warm dense hydrogen...

    Office of Scientific and Technical Information (OSTI)

    and conductivity of warm dense hydrogen Citation Details In-Document Search Title: Equilibration dynamics and conductivity of warm dense hydrogen You are accessing a document ...

  7. Equilibration dynamics and conductivity of warm dense hydrogen...

    Office of Scientific and Technical Information (OSTI)

    Equilibration dynamics and conductivity of warm dense hydrogen Citation Details In-Document Search Title: Equilibration dynamics and conductivity of warm dense hydrogen Authors: ...

  8. Ion-ion dynamic structure factor of warm dense mixtures

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

    Gill, N. M.; Heinonen, R. A.; Starrett, C. E.; Saumon, D.

    2015-06-25

    In this study, the ion-ion dynamic structure factor of warm dense matter is determined using the recently developed pseudoatom molecular dynamics method [Starrett et al., Phys. Rev. E 91, 013104 (2015)]. The method uses density functional theory to determine ion-ion pair interaction potentials that have no free parameters. These potentials are used in classical molecular dynamics simulations. This constitutes a computationally efficient and realistic model of dense plasmas. Comparison with recently published simulations of the ion-ion dynamic structure factor and sound speed of warm dense aluminum finds good to reasonable agreement. Using this method, we make predictions of the ion-ionmore » dynamical structure factor and sound speed of a warm dense mixture—equimolar carbon-hydrogen. This material is commonly used as an ablator in inertial confinement fusion capsules, and our results are amenable to direct experimental measurement.« less

  9. Ion-ion dynamic structure factor of warm dense mixtures

    SciTech Connect (OSTI)

    Gill, N. M.; Heinonen, R. A.; Starrett, C. E.; Saumon, D.

    2015-06-25

    In this study, the ion-ion dynamic structure factor of warm dense matter is determined using the recently developed pseudoatom molecular dynamics method [Starrett et al., Phys. Rev. E 91, 013104 (2015)]. The method uses density functional theory to determine ion-ion pair interaction potentials that have no free parameters. These potentials are used in classical molecular dynamics simulations. This constitutes a computationally efficient and realistic model of dense plasmas. Comparison with recently published simulations of the ion-ion dynamic structure factor and sound speed of warm dense aluminum finds good to reasonable agreement. Using this method, we make predictions of the ion-ion dynamical structure factor and sound speed of a warm dense mixture—equimolar carbon-hydrogen. This material is commonly used as an ablator in inertial confinement fusion capsules, and our results are amenable to direct experimental measurement.

  10. First-principles opacity table of warm dense deuterium forinertial...

    Office of Scientific and Technical Information (OSTI)

    ...ial-confinement-fusion applications Citation Details In-Document Search Title: First-principles opacity table of warm dense deuterium for inertial-confinement-fusion applications ...

  11. Measurement of electron-ion relaxation in warm dense copper

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

    Cho, B. I.; Ogitsu, T.; Engelhorn, K.; Correa, A. A.; Ping, Y.; Lee, J. W.; Bae, L. J.; Prendergast, D.; Falcone, R. W.; Heimann, P. A.

    2016-01-06

    Experimental investigation of electron-ion coupling and electron heat capacity of copper in warm and dense states are presented. From time-resolved x-ray absorption spectroscopy, the temporal evolution of electron temperature is obtained for non-equilibrium warm dense copper heated by an intense femtosecond laser pulse. Electron heat capacity and electron-ion coupling are inferred from the initial electron temperature and its decrease over 10 ps. As a result, data are compared with various theoretical models.

  12. Visualization of expanding warm dense gold and diamond heated rapidly by laser-generated ion beams

    SciTech Connect (OSTI)

    Bang, W.; Albright, B. J.; Bradley, P. A.; Gautier, D. C.; Palaniyappan, S.; Vold, E. L.; Cordoba, M. A. Santiago; Hamilton, C. E.; Fernández, J. C.

    2015-09-22

    With the development of several novel heating sources, scientists can now heat a small sample isochorically above 10,000 K. Although matter at such an extreme state, known as warm dense matter, is commonly found in astrophysics (e.g., in planetary cores) as well as in high energy density physics experiments, its properties are not well understood and are difficult to predict theoretically. This is because the approximations made to describe condensed matter or high-temperature plasmas are invalid in this intermediate regime. A sufficiently large warm dense matter sample that is uniformly heated would be ideal for these studies, but has been unavailable to date. We have used a beam of quasi-monoenergetic aluminum ions to heat gold and diamond foils uniformly and isochorically. For the first time, we visualized directly the expanding warm dense gold and diamond with an optical streak camera. Furthermore, we present a new technique to determine the initial temperature of these heated samples from the measured expansion speeds of gold and diamond into vacuum. We anticipate the uniformly heated solid density target will allow for direct quantitative measurements of equation-of-state, conductivity, opacity, and stopping power of warm dense matter, benefiting plasma physics, astrophysics, and nuclear physics.

  13. Visualization of expanding warm dense gold and diamond heated rapidly by laser-generated ion beams

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

    Bang, W.; Albright, B. J.; Bradley, P. A.; Gautier, D. C.; Palaniyappan, S.; Vold, E. L.; Cordoba, M. A. Santiago; Hamilton, C. E.; Fernández, J. C.

    2015-09-22

    With the development of several novel heating sources, scientists can now heat a small sample isochorically above 10,000 K. Although matter at such an extreme state, known as warm dense matter, is commonly found in astrophysics (e.g., in planetary cores) as well as in high energy density physics experiments, its properties are not well understood and are difficult to predict theoretically. This is because the approximations made to describe condensed matter or high-temperature plasmas are invalid in this intermediate regime. A sufficiently large warm dense matter sample that is uniformly heated would be ideal for these studies, but has beenmore » unavailable to date. We have used a beam of quasi-monoenergetic aluminum ions to heat gold and diamond foils uniformly and isochorically. For the first time, we visualized directly the expanding warm dense gold and diamond with an optical streak camera. Furthermore, we present a new technique to determine the initial temperature of these heated samples from the measured expansion speeds of gold and diamond into vacuum. We anticipate the uniformly heated solid density target will allow for direct quantitative measurements of equation-of-state, conductivity, opacity, and stopping power of warm dense matter, benefiting plasma physics, astrophysics, and nuclear physics.« less

  14. Ultrafast Spectroscopy of Warm Dense Matter

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

    can hardly be ignored. Clearly the theoretical modeling in this case is not straightforward. It is also a regime where good experimental data are in short supply. In this...

  15. Ultrafast Spectroscopy of Warm Dense Matter

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

    Not only is it prevalent throughout the universe, it is relevant to inertial confinement fusion (ICF) and material performance under extreme conditions. However, because of its ...

  16. Ultrafast Spectroscopy of Warm Dense Matter

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

    Pressures corresponding to this temperature and density are between 100,000 and one billion atmospheres. Figure from "Basic Research Needs for High Energy Density Laboratory ...

  17. Ultrafast Spectroscopy of Warm Dense Matter

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

    a way to freeze and capture such data in the split second before a laser-heated copper sample is destroyed. Our full understanding of planet formation and structures as well...

  18. Measurement of charged-particle stopping in warm-dense plasma

    SciTech Connect (OSTI)

    Zylstra, A.  B.; Frenje, J.  A.; Grabowski, P. E.; Li, C.  K.; Collins, G.  W.; Fitzsimmons, P.; Glenzer, S.; Graziani, F.; Hansen, S.  B.; Hu, S. X.; Johnson, M. Gatu; Keiter, P.; Reynolds, H.; Rygg, J.  R.; Séguin, F. H.; Petrasso, R. D.

    2015-05-27

    We measured the stopping of energetic protons in an isochorically-heated solid-density Be plasma with an electron temperature of ~32 eV, corresponding to moderately-coupled [(e²/a/(kBTe + EF ) ~ 0.3] and moderately-degenerate [kBTe/EF ~2] 'warm dense matter' (WDM) conditions. We present the first high-accuracy measurements of charged-particle energy loss through dense plasma, which shows an increased loss relative to cold matter, consistent with a reduced mean ionization potential. The data agree with stopping models based on an ad-hoc treatment of free and bound electrons, as well as the average-atom local-density approximation; this work is the first test of these theories in WDM plasma.

  19. Measurement of charged-particle stopping in warm-dense plasma

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

    Zylstra, A.  B.; Frenje, J.  A.; Grabowski, P. E.; Li, C.  K.; Collins, G.  W.; Fitzsimmons, P.; Glenzer, S.; Graziani, F.; Hansen, S.  B.; Hu, S. X.; et al

    2015-05-27

    We measured the stopping of energetic protons in an isochorically-heated solid-density Be plasma with an electron temperature of ~32 eV, corresponding to moderately-coupled [(e²/a/(kBTe + EF ) ~ 0.3] and moderately-degenerate [kBTe/EF ~2] 'warm dense matter' (WDM) conditions. We present the first high-accuracy measurements of charged-particle energy loss through dense plasma, which shows an increased loss relative to cold matter, consistent with a reduced mean ionization potential. The data agree with stopping models based on an ad-hoc treatment of free and bound electrons, as well as the average-atom local-density approximation; this work is the first test of these theories inmore » WDM plasma.« less

  20. Models of the elastic x-ray scattering feature for warm dense aluminum

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

    Starrett, Charles Edward; Saumon, Didier

    2015-09-03

    The elastic feature of x-ray scattering from warm dense aluminum has recently been measured by Fletcher et al. [Nature Photonics 9, 274 (2015)] with much higher accuracy than had hitherto been possible. This measurement is a direct test of the ionic structure predicted by models of warm dense matter. We use the method of pseudoatom molecular dynamics to predict this elastic feature for warm dense aluminum with temperatures of 1–100 eV and densities of 2.7–8.1g/cm3. We compare these predictions to experiments, finding good agreement with Fletcher et al. and corroborating the discrepancy found in analyses of an earlier experiment ofmore » Ma et al. [Phys. Rev. Lett. 110, 065001 (2013)]. Lastly, we also evaluate the validity of the Thomas-Fermi model of the electrons and of the hypernetted chain approximation in computing the elastic feature and find them both wanting in the regime currently probed by experiments.« less

  1. Models of the elastic x-ray scattering feature for warm dense aluminum

    SciTech Connect (OSTI)

    Starrett, Charles Edward; Saumon, Didier

    2015-09-03

    The elastic feature of x-ray scattering from warm dense aluminum has recently been measured by Fletcher et al. [Nature Photonics 9, 274 (2015)] with much higher accuracy than had hitherto been possible. This measurement is a direct test of the ionic structure predicted by models of warm dense matter. We use the method of pseudoatom molecular dynamics to predict this elastic feature for warm dense aluminum with temperatures of 1–100 eV and densities of 2.7–8.1g/cm3. We compare these predictions to experiments, finding good agreement with Fletcher et al. and corroborating the discrepancy found in analyses of an earlier experiment of Ma et al. [Phys. Rev. Lett. 110, 065001 (2013)]. Lastly, we also evaluate the validity of the Thomas-Fermi model of the electrons and of the hypernetted chain approximation in computing the elastic feature and find them both wanting in the regime currently probed by experiments.

  2. Magnetic Phases in Dense Quark Matter

    SciTech Connect (OSTI)

    Incera, Vivian de la

    2007-10-26

    In this paper I discuss the magnetic phases of the three-flavor color superconductor. These phases can take place at different field strengths in a highly dense quark system. Given that the best natural candidates for the realization of color superconductivity are the extremely dense cores of neutron stars, which typically have very large magnetic fields, the magnetic phases here discussed could have implications for the physics of these compact objects.

  3. Ab initio determination of the instability growth rate of warm dense beryllium-deuterium interface

    SciTech Connect (OSTI)

    Wang, Cong; Zhang, Ping; Li, Zi; Li, DaFang

    2015-10-15

    Accurate knowledge about the interfacial unstable growth is of great importance in inertial confinement fusion. During implosions, the deuterium-tritium capsule is driven by laser beams or X-rays to access the strongly coupled and partially degenerated warm dense matter regime. At this stage, the effects of dissipative processes, such as diffusion and viscosity, have significant impact on the instability growth rates. Here, we present ab initio molecular dynamics simulations to determine the equations of state and the transport coefficients. Several models are used to estimate the reduction in the growth rate dispersion curves of Rayleigh-Taylor and Richtmyer-Meshkov instabilities with considering the presence of these dissipative effects. We show that these instability growth rates are effectively reduced when considering diffusion. The findings provide significant insights into the microscopic mechanism of the instability growth at the ablator-fuel interface and will refine the models used in the laser-driven hydrodynamic instability experiments.

  4. First-principles calculation of principal Hugoniot and K-shell X-ray absorption spectra for warm dense KCl

    SciTech Connect (OSTI)

    Zhao, Shijun; Zhang, Shen; Kang, Wei; Li, Zi; Zhang, Ping; He, Xian-Tu

    2015-06-15

    Principal Hugoniot and K-shell X-ray absorption spectra of warm dense KCl are calculated using the first-principles molecular dynamics (FPMD) method. Evolution of electronic structures as well as the influence of the approximate description of ionization on pressure (caused by the underestimation of the energy gap between conduction bands and valence bands) in the first-principles method are illustrated by the calculation. It is shown that approximate description of ionization in FPMD has small influence on Hugoniot pressure due to mutual compensation of electronic kinetic pressure and virial pressure. The calculation of X-ray absorption spectra shows that the band gap of KCl persists after the pressure ionization of the 3p electrons of Cl and K taking place at lower energy, which provides a detailed understanding to the evolution of electronic structures of warm dense matter.

  5. Probing warm dense silica with betatron radiation - Oral Presentation

    SciTech Connect (OSTI)

    Kotick, Jordan

    2015-08-24

    Laser wakefield acceleration (LWFA) has been shown to produce short X-ray pulses from oscillations of electrons within the plasma wake. These betatron X-rays pulses have a broad, synchrotron-like energy spectrum and a duration on the order of the driving laser pulse, thereby enabling probing of ultrafast interactions. Using the 1 J, 40fs short-pulse laser at the Matter in Extreme Conditions experimental station at LCLS, we have implemented LWFA to generate and subsequently characterized betatron X-rays. A scintillator and lanex screen were used to measure the charge fluence and energy spectrum of the produced electron beam.

  6. Soft X-Ray Thomson Scattering in Warm Dense Hydrogen at FLASH

    SciTech Connect (OSTI)

    Faustlin, R R; Toleikis, S; Bornath, T; Doppner, T; Dusterer, S; Forster, E; Fortmann, C; Glenzer, S H; Gode, S; Gregori, G; Irsig, R; Laarmann, T; Lee, H J; Li, B; Meiwes-Broer, K; Mithen, J; Przystawik, A; Redlin, H; Redmer, R; Reinholz, H; Ropke, G; Tavella, F; Thiele, R; Tiggesbaumker, J; Uschmann, I; Zastrau, U; Tschentscher, T

    2009-07-15

    We present collective Thomson scattering with soft x-ray free electron laser radiation as a method to track the evolution of warm dense matter plasmas with {approx}200 fs time resolution. In a pump-probe scheme an 800 nm laser heats a 20 {micro}m hydrogen droplet to the plasma state. After a variable time delay in the order of ps the plasma is probed by an x-ray ultra violet (XUV) pulse which scatters from the target and is recorded spectrally. Alternatively, in a self-Thomson scattering experiment, a single XUV pulse heats the target while a portion of its photons are being scattered probing the target. From such inelastic x-ray scattering spectra free electron temperature and density can be inferred giving insight on relaxation time scales in plasmas as well as the equation of state. We prove the feasibility of this method in the XUV range utilizing the free electron laser facility in Hamburg, FLASH. We recorded Thomson scattering spectra for hydrogen plasma, both in the self-scattering and in the pump-probe mode using optical laser heating.

  7. Topical Collaboration "Neutrinos and Nucleosynthesis in Hot and Dense Matter"

    SciTech Connect (OSTI)

    Allahverdi, Rouzbeh

    2015-09-18

    This is the final technical report describing contributions from the University of New Mexico to Topical Collaboration on "Neutrinos and Nucleosynthesis in Hot and Dense Matter" in the period June 2010 through May 2015. During the funding period, the University of New Mexico successfully hired Huaiyu Duan as a new faculty member with the support from DOE, who has contributed to the Topical Collaboration through his research and collaborations.

  8. Laboratory measurements of resistivity in warm dense plasmas relevant to the microphysics of brown dwarfs

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

    Booth, N.; Robinson, A. P. L.; Hakel, P.; Clarke, R. J.; Dance, R. J.; Doria, D.; Gizzi, L. A.; Gregori, G.; Koester, P.; Labate, L.; et al

    2015-11-06

    Since the observation of the first brown dwarf in 1995, numerous studies have led to a better understanding of the structures of these objects. Here we present a method for studying material resistivity in warm dense plasmas in the laboratory, which we relate to the microphysics of brown dwarfs through viscosity and electron collisions. Here we use X-ray polarimetry to determine the resistivity of a sulphur-doped plastic target heated to Brown Dwarf conditions by an ultra-intense laser. The resistivity is determined by matching the plasma physics model to the atomic physics calculations of the measured large, positive, polarization. Furthermore, themore » inferred resistivity is larger than predicted using standard resistivity models, suggesting that these commonly used models will not adequately describe the resistivity of warm dense plasma related to the viscosity of brown dwarfs.« less

  9. Laboratory measurements of resistivity in warm dense plasmas relevant to the microphysics of brown dwarfs

    SciTech Connect (OSTI)

    Booth, N.; Robinson, A. P. L.; Hakel, P.; Clarke, R. J.; Dance, R. J.; Doria, D.; Gizzi, L. A.; Gregori, G.; Koester, P.; Labate, L.; Levato, T.; Li, B.; Makita, M.; Mancini, R. C.; Pasley, J.; Rajeev, P. P.; Riley, D.; Wagenaars, E.; Waugh, J. N.; Woolsey, N. C.

    2015-11-06

    Since the observation of the first brown dwarf in 1995, numerous studies have led to a better understanding of the structures of these objects. Here we present a method for studying material resistivity in warm dense plasmas in the laboratory, which we relate to the microphysics of brown dwarfs through viscosity and electron collisions. Here we use X-ray polarimetry to determine the resistivity of a sulphur-doped plastic target heated to Brown Dwarf conditions by an ultra-intense laser. The resistivity is determined by matching the plasma physics model to the atomic physics calculations of the measured large, positive, polarization. Furthermore, the inferred resistivity is larger than predicted using standard resistivity models, suggesting that these commonly used models will not adequately describe the resistivity of warm dense plasma related to the viscosity of brown dwarfs.

  10. Observations of Continuum Depression in Warm Dense Matter with...

    Office of Scientific and Technical Information (OSTI)

    ; Jones, O. S. ; Landen, O. L. ; Scott, H. A. ; LLNL ; Vorberger, J. ; Dresden, Max Planck Inst ; Chapman, D. A. ; AWE plc, Reading ; Gericke, D. O. ; Warwick U. ; Mattern, B. ...

  11. The physics of hot and dense quark-gluon matter

    SciTech Connect (OSTI)

    Kharzeev, Dmitri E

    2012-05-10

    This technical report describes the work done under the DOE grant DE-FG-88ER41723 (final award number DE-SC0005645), "The physics of hot and dense quark-gluon matter", during the year of 12/01/2010 through 11/30/2011. As planned in the proposal, the performed research focused along two main thrusts: 1) topological effects in hot quark-gluon matter and 2) phenomenology of relativistic heavy ion collisions. The results of research are presented in 12 papers published in reputable refereed journals (Physical Review Letters, Physical Review, Physics Letters and Nuclear Physics). All of the performed research is directly related to the experimental programs of DOE, especially at the Relativistic Heavy Ion Collider. Much of it also has broader interdisciplinary implications - for example, the work on the non-dissipative chiral magnetic current is directly relevant for quantum computing. The attached report describes the performed work in detail.

  12. Warm and cold fermionic dark matter via freeze-in

    SciTech Connect (OSTI)

    Klasen, Michael; Yaguna, Carlos E. E-mail: carlos.yaguna@uni-muenster.de

    2013-11-01

    The freeze-in mechanism of dark matter production provides a simple and intriguing alternative to the WIMP paradigm. In this paper, we analyze whether freeze-in can be used to account for the dark matter in the so-called singlet fermionic model. In it, the SM is extended with only two additional fields, a singlet scalar that mixes with the Higgs boson, and the dark matter particle, a fermion assumed to be odd under a Z{sub 2} symmetry. After numerically studying the generation of dark matter, we analyze the dependence of the relic density with respect to all the free parameters of the model. These results are then used to obtain the regions of the parameter space that are compatible with the dark matter constraint. We demonstrate that the observed dark matter abundance can be explained via freeze-in over a wide range of masses extending down to the keV range. As a result, warm and cold dark matter can be obtained in this model. It is also possible to have dark matter masses well above the unitarity bound for WIMPs.

  13. Dynamics of charge clouds ejected from laser-induced warm dense gold nanofilms

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

    Zhou, Jun; Li, Junjie; Correa, Alfredo A.; Tang, Shao; Ping, Yuan; Ogitsu, Tadashi; Li, Dong; Zhou, Qiong; Cao, Jianming

    2014-10-24

    We report the first systematic study of the ejected charge dynamics surrounding laser-produced 30-nm warm dense gold films using single-shot femtosecond electron shadow imaging and deflectometry. The results reveal a two-step dynamical process of the ejected electrons under the high pump fluence conditions: an initial emission and accumulation of a large amount of electrons near the pumped surface region followed by the formation of hemispherical clouds of electrons on both sides of the film, which are escaping into the vacuum at a nearly isotropic and constant velocity with an unusually high kinetic energy of more than 300 eV. We alsomore » developed a model of the escaping charge distribution that not only reproduces the main features of the observed charge expansion dynamics but also allows us to extract the number of ejected electrons remaining in the cloud.« less

  14. Equations of state and transport properties of mixtures in the warm dense regime

    SciTech Connect (OSTI)

    Hou, Yong; Dai, Jiayu; Kang, Dongdong; Ma, Wen; Yuan, Jianmin

    2015-02-15

    We have performed average-atom molecular dynamics to simulate the CH and LiH mixtures in the warm dense regime, and obtained equations of state and the ionic transport properties. The electronic structures are calculated by using the modified average-atom model, which have included the broadening of energy levels, and the ion-ion pair potentials of mixtures are constructed based on the temperature-dependent density functional theory. The ionic transport properties, such as ionic diffusion and shear viscosity, are obtained through the ionic velocity correlation functions. The equations of state and transport properties for carbon, hydrogen and lithium, hydrogen mixtures in a wide region of density and temperature are calculated. Through our computing the average ionization degree, average ion-sphere diameter and transition properties in the mixture, it is shown that transport properties depend not only on the ionic mass but also on the average ionization degree.

  15. Dynamics of charge clouds ejected from laser-induced warm dense gold nanofilms

    SciTech Connect (OSTI)

    Zhou, Jun; Li, Junjie; Correa, Alfredo A.; Tang, Shao; Ping, Yuan; Ogitsu, Tadashi; Li, Dong; Zhou, Qiong; Cao, Jianming

    2014-10-24

    We report the first systematic study of the ejected charge dynamics surrounding laser-produced 30-nm warm dense gold films using single-shot femtosecond electron shadow imaging and deflectometry. The results reveal a two-step dynamical process of the ejected electrons under the high pump fluence conditions: an initial emission and accumulation of a large amount of electrons near the pumped surface region followed by the formation of hemispherical clouds of electrons on both sides of the film, which are escaping into the vacuum at a nearly isotropic and constant velocity with an unusually high kinetic energy of more than 300 eV. We also developed a model of the escaping charge distribution that not only reproduces the main features of the observed charge expansion dynamics but also allows us to extract the number of ejected electrons remaining in the cloud.

  16. Dynamics of charge clouds ejected from laser-induced warm dense gold nanofilms

    SciTech Connect (OSTI)

    Zhou, Jun; Li, Junjie; Correa, Alfredo A.; Tang, Shao; Ping, Yuan; Ogitsu, Tadashi; Li, Dong; Zhou, Qiong; Cao, Jianming

    2014-10-24

    We report the first systematic study of the ejected charge dynamics surrounding laser-produced 30- nm warm dense gold films using single-shot femtosecond electron shadow imaging and deflectometry. The results reveal a two-step dynamical process of the ejected electrons under the high pump fluence conditions: an initial emission and accumulation of a large amount of electrons near the pumped surface region followed by the formation of hemispherical clouds of electrons on both sides of the film, which are escaping into the vacuum at a nearly isotropic and constant velocity with an unusually high kinetic energy of more than 300 eV. We also developed a model of the escaping charge distribution that not only reproduces the main features of the observed charge expansion dynamics but also allows us to extract the number of ejected electrons remaining in the cloud.

  17. Emission of Visible Light by Hot Dense Metals (Conference) |...

    Office of Scientific and Technical Information (OSTI)

    TRANSPORT THEORY Incandescent emission of light, polarized emission, pyrometry, hot metals, warm dense matter. Word Cloud More Like This Full Text preview image File size N...

  18. Evolution of Elastic X-ray Scattering in Laser-Shocked Warm Dense Li

    SciTech Connect (OSTI)

    Kugland, N L; Gregori, G; Bandyopadhyay, S; Brenner, C; Brown, C; Constantin, C; Glenzer, S H; Khattak, F; Kritcher, A L; Niemann, C; Otten, A; Pasley, J; Pelka, A; Roth, M; Spindloe, C; Riley, D

    2009-06-02

    We have studied the dynamics of warm dense Li with near-elastic x-ray scattering. Li foils were heated and compressed using shock waves driven by 4 ns long laser pulses. Separate 1 ns long laser pulses were used to generate a bright source of 2.96 keV Cl Ly-{alpha} photons for x-ray scattering, and the spectrum of scattered photons was recorded at a scattering angle of 120{sup o} using a HOPG crystal operated in the von Hamos geometry. A variable delay between the heater and backlighter laser beams measured the scattering time evolution. Comparison with radiation hydrodynamics simulations shows that the plasma is highly coupled during the first several nanoseconds, then relaxes to a moderate coupling state at later times. Near-elastic scattering amplitudes have been successfully simulated using the screened one-component plasma model. Our main finding is that the near-elastic scattering amplitudes are quite sensitive to the mean ionization state {bar Z}, and by extension to the choice of ionization model in the radiation-hydrodynamics simulations used to predict plasma properties within the shocked Li.

  19. Hyperon-Nucleon Interactions and the Composition of Dense Matter from Quantum Chromodynamics

    SciTech Connect (OSTI)

    Konstantinos Orginos, Silas Beane, Emmanuel Chang, Saul Cohen, Huey-Wen Lin, Tom Luu, Assumpta Parreno, Martin Savage, Andre Walker-Loud, William Detmold

    2012-10-01

    The low-energy n{Sigma}{sup -} interactions determine, in part, the role of the strange quark in dense matter, such as that found in astrophysical environments. The scattering phase-shifts for this system are determined from a numerical evaluation of the QCD path integral using the technique of Lattice QCD. Our results, performed at a pion mass of m{sub {pi}} ~ 389 MeV in two large lattice volumes, and at one lattice spacing, are extrapolated to the physical pion mass using effective field theory. The calculated interactions indicate that the strange quark plays an important role in dense matter.

  20. Combined x-ray scattering, radiography, and velocity interferometry/streaked optical pyrometry measurements of warm dense carbon using a novel technique of shock-and-release

    SciTech Connect (OSTI)

    Falk, K.; Collins, L. A.; Kagan, G.; Kress, J. D.; Montgomery, D. S.; Srinivasan, B.; Gamboa, E. J.; Tzeferacos, P.; Benage, J. F.

    2014-05-15

    This work focused on a new application of the shock-and-release technique for equation of state (EOS) measurements. Warm dense matter states at near normal solid density and at temperatures close to 10 eV in diamond and graphite samples were created using a deep release from a laser-driven shock at the OMEGA laser facility. Independent temperature, density, and pressure measurements that do not depend on any theoretical models or simulations were obtained using imaging x-ray Thomson scattering, radiography, velocity interferometry, and streaked optical pyrometry. The experimental results were reproduced by the 2-D FLASH radiation hydrodynamics simulations finding a good agreement. The final EOS measurement was then compared with widely used SESAME EOS models as well as quantum molecular dynamics simulation results for carbon, which were very consistent with the experimental data.

  1. Nonlinear evolution of dark matter subhalos and applications to warm dark matter

    SciTech Connect (OSTI)

    Pullen, Anthony R.; Moustakas, Leonidas A.; Benson, Andrew J.

    2014-09-01

    We describe the methodology to include nonlinear evolution, including tidal effects, in the computation of subhalo distribution properties in both cold (CDM) and warm (WDM) dark matter universes. Using semi-analytic modeling, we include effects from dynamical friction, tidal stripping, and tidal heating, allowing us to dynamically evolve the subhalo distribution. We calibrate our nonlinear evolution scheme to the CDM subhalo mass function in the Aquarius N-body simulation, producing a subhalo mass function within the range of simulations. We find tidal effects to be the dominant mechanism of nonlinear evolution in the subhalo population. Finally, we compute the subhalo mass function for m {sub χ} = 1.5 keV WDM including the effects of nonlinear evolution, and compare radial number densities and mass density profiles of subhalos in CDM and WDM models. We show that all three signatures differ between the two dark matter models, suggesting that probes of substructure may be able to differentiate between them.

  2. Hyperon-Nucleon Interactions and the Composition of Dense Nuclear Matter from Quantum Chromodynamics

    SciTech Connect (OSTI)

    Beane, S R; Cohen, S D; Detmold, W; Lin, H -W; Luu, T C; Orginos, K; Parreno, A; Savage, M J

    2012-10-01

    The low-energy neutron-{Sigma}{sup -} interactions determine, in part, the role of the strange quark in dense matter, such as that found in astrophysical environments. The scattering phase shifts for this system are obtained from a numerical evaluation of the QCD path integral using the technique of Lattice QCD. Our calculations, performed at a pion mass of m{sub pi} ~ 389 MeV in two large lattice volumes, and at one lattice spacing, are extrapolated to the physical pion mass using effective field theory. The interactions determined from QCD are consistent with those extracted from hyperon-nucleon experimental data within uncertainties, and strengthen theoretical arguments that the strange quark is a crucial component of dense nuclear matter.

  3. Chiral asymmetry of the Fermi surface in dense relativistic matter in a magnetic field

    SciTech Connect (OSTI)

    Gorbar, E. V.; Miransky, V. A.; Shovkovy, I. A.

    2009-09-15

    It is revealed that in the normal phase of dense relativistic matter in a magnetic field, there exists a contribution to the axial current associated with a relative shift of the longitudinal momenta in the dispersion relations of opposite chirality fermions. Unlike the topological contribution in the axial current at the lowest Landau level, recently discussed in the literature, the dynamical one appears only in interacting matter and affects the fermions in all Landau levels, including those around the Fermi surface. The induced axial current and the shift of the Fermi surfaces of the left-handed and right-handed fermions are expected to play an important role in transport and emission properties of matter in various types of compact stars as well as in heavy ion collisions.

  4. The Cold Dark Matter Search test stand warm electronics card

    SciTech Connect (OSTI)

    Hines, Bruce; Hansen, Sten; Huber, Martin; Kiper, Terry; Rau, Wolfgang; Saab, Tarek; Seitz, Dennis; Sundqvist, Kyle; Mandic, Vuk; /Minnesota U.

    2010-11-01

    A card which does the signal processing for four SQUID amplifiers and two charge sensitive channels is described. The card performs the same functions as is presently done with two custom 9U x 280mm Eurocard modules, a commercial multi-channel VME digitizer, a PCI to GPIB interface, a PCI to VME interface and a custom built linear power supply. By integrating these functions onto a single card and using the power over Ethernet standard, the infrastructure requirements for instrumenting a Cold Dark Matter Search (CDMS) detector test stand are significantly reduced.

  5. Equation of state and transport property measurements of warm dense matter.

    SciTech Connect (OSTI)

    Knudson, Marcus D.; Desjarlais, Michael Paul

    2009-10-01

    Location of the liquid-vapor critical point (c.p.) is one of the key features of equation of state models used in simulating high energy density physics and pulsed power experiments. For example, material behavior in the location of the vapor dome is critical in determining how and when coronal plasmas form in expanding wires. Transport properties, such as conductivity and opacity, can vary an order of magnitude depending on whether the state of the material is inside or outside of the vapor dome. Due to the difficulty in experimentally producing states near the vapor dome, for all but a few materials, such as Cesium and Mercury, the uncertainty in the location of the c.p. is of order 100%. These states of interest can be produced on Z through high-velocity shock and release experiments. For example, it is estimated that release adiabats from {approx}1000 GPa in aluminum would skirt the vapor dome allowing estimates of the c.p. to be made. This is within the reach of Z experiments (flyer plate velocity of {approx}30 km/s). Recent high-fidelity EOS models and hydrocode simulations suggest that the dynamic two-phase flow behavior observed in initial scoping experiments can be reproduced, providing a link between theory and experiment. Experimental identification of the c.p. in aluminum would represent the first measurement of its kind in a dynamic experiment. Furthermore, once the c.p. has been experimentally determined it should be possible to probe the electrical conductivity, opacity, reflectivity, etc. of the material near the vapor dome, using a variety of diagnostics. We propose a combined experimental and theoretical investigation with the initial emphasis on aluminum.

  6. Normal ground state of dense relativistic matter in a magnetic field

    SciTech Connect (OSTI)

    Gorbar, E. V.; Miransky, V. A.; Shovkovy, I. A.

    2011-04-15

    The properties of the ground state of relativistic matter in a magnetic field are examined within the framework of a Nambu-Jona-Lasinio model. The main emphasis of this study is the normal ground state, which is realized at sufficiently high temperatures and/or sufficiently large chemical potentials. In contrast to the vacuum state, which is characterized by the magnetic catalysis of chiral symmetry breaking, the normal state is accompanied by the dynamical generation of the chiral shift parameter {Delta}. In the chiral limit, the value of {Delta} determines a relative shift of the longitudinal momenta (along the direction of the magnetic field) in the dispersion relations of opposite chirality fermions. We argue that the chirality remains a good approximate quantum number even for massive fermions in the vicinity of the Fermi surface and, therefore, the chiral shift is expected to play an important role in many types of cold dense relativistic matter, relevant for applications in compact stars. The qualitative implications of the revealed structure of the normal ground state on the physics of protoneutron stars are discussed. A noticeable feature of the {Delta} parameter is that it is insensitive to temperature when T<<{mu}{sub 0}, where {mu}{sub 0} is the chemical potential, and increases with temperature for T>{mu}{sub 0}. The latter implies that the chiral shift parameter is also generated in the regime relevant for heavy ion collisions.

  7. Proceedings of RIKEN BNL Research Center Workshop: P- and CP-odd Effects in Hot and Dense Matter

    SciTech Connect (OSTI)

    Deshpande, A.; Fukushima, K.; Kharzeev, D.; Warringa, H.; Voloshin, S.

    2010-04-26

    This volume contains the proceedings of the RBRC/CATHIE workshop on 'P- and CP-odd Effects in Hot and Dense Matter' held at the RIKEN-BNL Research Center on April 26-30, 2010. The workshop was triggered by the experimental observation of charge correlations in heavy ion collisions at RHIC, which were predicted to occur due to local parity violation (P- and CP-odd fluctuations) in hot and dense QCD matter. This experimental result excited a significant interest in the broad physics community, inspired a few alternative interpretations, and emphasized the need for a deeper understanding of the role of topology in QCD vacuum and in hot and dense quark-gluon matter. Topological effects in QCD are also closely related to a number of intriguing problems in condensed matter physics, cosmology and astrophysics. We therefore felt that a broad cross-disciplinary discussion of topological P- and CP-odd effects in various kinds of matter was urgently needed. Such a discussion became the subject of the workshop. Specific topics discussed at the workshop include the following: (1) The current experimental results on charge asymmetries at RHIC and the physical interpretations of the data; (2) Quantitative characterization of topological effects in QCD matter including both analytical (perturbative and non-perturbative using gauge/gravity duality) and numerical (lattice-QCD) calculations; (3) Topological effects in cosmology of the Early Universe (including baryogenesis and dark energy); (4) Topological effects in condensed matter physics (including graphene and superfiuids); and (5) Directions for the future experimental studies of P- and CP-odd effects at RHIC and elsewhere. We feel that the talks and intense discussions during the workshop were extremely useful, and resulted in new ideas in both theory and experiment. We hope that the workshop has contributed to the progress in understanding the role of topology in QCD and related fields. We thank all the speakers and

  8. A Unified Equation for the Reaction Rate in Dense Matter Stars

    SciTech Connect (OSTI)

    Gasques, L. R.; Wiescher, M.; Yakovlev, D. G.

    2007-10-26

    We analyze thermonuclear and pycnonuclear reaction rates in multi-component dense stellar plasma. First we describe calculations of the astrophysical S-factor at low energies using the Sao Paulo potential on the basis of the barrier penetration model. Then we present a simple phenomenological expression for a reaction rate. The expression contains several fit parameters which we adjust to reproduce the best microscopic calculations available in the literature.

  9. LPM Interference and Cherenkov-like Gluon Bremsstrahlung in DenseMatter

    SciTech Connect (OSTI)

    Majumder, Abhijit; Wang, Xin-Nian

    2005-07-26

    Gluon bremsstrahlung induced by multiple parton scattering in a finite dense medium has a unique angular distribution with respect to the initial parton direction. A dead-cone structure with an opening angle; theta2{sub 0}; approx 2(1-z)/(zLE) for gluons with fractional energy z arises from the Landau-Pomeran chuck-Migdal (LPM) interference. In a medium where the gluon's dielectric constant is; epsilon>1, the LPM interference pattern is shown to become Cherenkov-like with an increased opening angle determined by the dielectric constant$/cos2/theta{sub c}=z+(1-z)//epsilon$. For a large dielectric constant/epsilon; gg 1+2/z2LE, the corresponding total radiative parton energy loss is about twice that from normal gluon bremsstrahlung. Implications of this Cherenkov-like gluon bremsstrahlung to the jet correlation pattern in high-energy heavy-ion collisions is discussed.

  10. Probing properties of hot and dense QCD matter with heavy flavor in the PHENIX experiment at RHIC

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

    Nouicer, Rachid

    2015-05-29

    Hadrons carrying heavy quarks, i.e. charm or bottom, are important probes of the hot and dense medium created in relativistic heavy ion collisions. Heavy quark-antiquark pairs are mainly produced in initial hard scattering processes of partons. While some of the produced pairs form bound quarkonia, the vast majority hadronize into particles carrying open heavy flavor. Heavy quark production has been studied by the PHENIX experiment at RHIC via measurements of single leptons from semi-leptonic decays in both the electron channel at mid-rapidity and in the muon channel at forward rapidity. A large suppression and azimuthal anisotropy of single electrons havemore » been observed in Au + Au collisions at 200 GeV. These results suggest a large energy loss and flow of heavy quarks in the hot, dense matter. The PHENIX experiment has also measured J/ψ production at 200 GeV in p + p, d + Au, Cu + Cu and Au + Au collisions, both at mid- and forward-rapidities, and additionally Cu + Au and U + U at forward-rapidities. In the most energetic collisions, more suppression is observed at forward rapidity than at central rapidity. This can be interpreted either as a sign of quark recombination, or as a hint of additional cold nuclear matter effects. The centrality dependence of nuclear modification factor, RAA(pT), for J/ψ in U + U collisions at √sNN = 193 GeV shows a similar trend to the lighter systems, Au + Au and Cu + Cu, at similar energy 200 GeV.« less

  11. Probing properties of hot and dense QCD matter with heavy flavor in the PHENIX experiment at RHIC

    SciTech Connect (OSTI)

    Nouicer, Rachid

    2015-05-29

    Hadrons carrying heavy quarks, i.e. charm or bottom, are important probes of the hot and dense medium created in relativistic heavy ion collisions. Heavy quark-antiquark pairs are mainly produced in initial hard scattering processes of partons. While some of the produced pairs form bound quarkonia, the vast majority hadronize into particles carrying open heavy flavor. Heavy quark production has been studied by the PHENIX experiment at RHIC via measurements of single leptons from semi-leptonic decays in both the electron channel at mid-rapidity and in the muon channel at forward rapidity. A large suppression and azimuthal anisotropy of single electrons have been observed in Au + Au collisions at 200 GeV. These results suggest a large energy loss and flow of heavy quarks in the hot, dense matter. The PHENIX experiment has also measured J/ψ production at 200 GeV in p + p, d + Au, Cu + Cu and Au + Au collisions, both at mid- and forward-rapidities, and additionally Cu + Au and U + U at forward-rapidities. In the most energetic collisions, more suppression is observed at forward rapidity than at central rapidity. This can be interpreted either as a sign of quark recombination, or as a hint of additional cold nuclear matter effects. The centrality dependence of nuclear modification factor, RAA(pT), for J/ψ in U + U collisions at √sNN = 193 GeV shows a similar trend to the lighter systems, Au + Au and Cu + Cu, at similar energy 200 GeV.

  12. Uniform heating of materials into the warm dense matter regime with laser-driven quasimonoenergetic ion beams

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

    Bang, W.; Albright, B. J.; Bradley, P. A.; Vold, E. L.; Boettger, J. C.; Fernández, J. C.

    2015-12-01

    In a recent experiment at the Trident laser facility, a laser-driven beam of quasimonoenergetic aluminum ions was used to heat solid gold and diamond foils isochorically to 5.5 and 1.7 eV, respectively. Here theoretical calculations are presented that suggest the gold and diamond were heated uniformly by these laser-driven ion beams. According to calculations and SESAME equation-of-state tables, laser-driven aluminum ion beams achievable at Trident, with a finite energy spread of ΔE/E~20%, are expected to heat the targets more uniformly than a beam of 140-MeV aluminum ions with zero energy spread. As a result, the robustness of the expected heatingmore » uniformity relative to the changes in the incident ion energy spectra is evaluated, and expected plasma temperatures of various target materials achievable with the current experimental platform are presented.« less

  13. Uniform heating of materials into the warm dense matter regime with laser-driven quasimonoenergetic ion beams

    SciTech Connect (OSTI)

    Bang, W.; Albright, B. J.; Bradley, P. A.; Vold, E. L.; Boettger, J. C.; Fernández, J. C.

    2015-12-01

    In a recent experiment at the Trident laser facility, a laser-driven beam of quasimonoenergetic aluminum ions was used to heat solid gold and diamond foils isochorically to 5.5 and 1.7 eV, respectively. Here theoretical calculations are presented that suggest the gold and diamond were heated uniformly by these laser-driven ion beams. According to calculations and SESAME equation-of-state tables, laser-driven aluminum ion beams achievable at Trident, with a finite energy spread of ΔE/E~20%, are expected to heat the targets more uniformly than a beam of 140-MeV aluminum ions with zero energy spread. As a result, the robustness of the expected heating uniformity relative to the changes in the incident ion energy spectra is evaluated, and expected plasma temperatures of various target materials achievable with the current experimental platform are presented.

  14. Transport properties and equation of state for HCNO mixtures in and beyond the warm dense matter regime

    SciTech Connect (OSTI)

    Ticknor, Christopher; Collins, Lee A.; Kress, Joel D.

    2015-08-04

    We present simulations of a four component mixture of HCNO with orbital free molecular dynamics (OFMD). These simulations were conducted for 5200 eV with densities ranging between 0.184 and 36.8 g/cm3. We extract the equation of state from the simulations and compare to average atom models. We found that we only need to add a cold curve model to find excellent agreement. In addition, we studied mass transport properties. We present fits to the self-diffusion and shear viscosity that are able to reproduce the transport properties over the parameter range studied. We compare these OFMD results to models based on the Coulomb coupling parameter and one-component plasmas.

  15. Transport properties and equation of state for HCNO mixtures in and beyond the warm dense matter regime

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

    Ticknor, Christopher; Collins, Lee A.; Kress, Joel D.

    2015-08-04

    We present simulations of a four component mixture of HCNO with orbital free molecular dynamics (OFMD). These simulations were conducted for 5–200 eV with densities ranging between 0.184 and 36.8 g/cm3. We extract the equation of state from the simulations and compare to average atom models. We found that we only need to add a cold curve model to find excellent agreement. In addition, we studied mass transport properties. We present fits to the self-diffusion and shear viscosity that are able to reproduce the transport properties over the parameter range studied. We compare these OFMD results to models based onmore » the Coulomb coupling parameter and one-component plasmas.« less

  16. Transport properties and equation of state for HCNO mixtures in and beyond the warm dense matter regime

    SciTech Connect (OSTI)

    Ticknor, Christopher; Collins, Lee A.; Kress, Joel D.

    2015-08-04

    We present simulations of a four component mixture of HCNO with orbital free molecular dynamics (OFMD). These simulations were conducted for 5–200 eV with densities ranging between 0.184 and 36.8 g/cm3. We extract the equation of state from the simulations and compare to average atom models. We found that we only need to add a cold curve model to find excellent agreement. In addition, we studied mass transport properties. We present fits to the self-diffusion and shear viscosity that are able to reproduce the transport properties over the parameter range studied. We compare these OFMD results to models based on the Coulomb coupling parameter and one-component plasmas.

  17. Unraveling resistive versus collisional contributions to relativistic electron beam stopping power in cold-solid and in warm-dense plasmas

    SciTech Connect (OSTI)

    Vauzour, B.; Laboratoire d'Optique Applique, ENSTA-CNRS-Ecole Polytechnique, UMR 7639, 91761 Palaiseau ; Debayle, A.; CEA, DAM, DIF, F-91297 Arpajon ; Vaisseau, X.; Hulin, S.; Nicola, Ph.; Dorchies, F.; Fourment, C.; D'Humires, E.; Tikhonchuk, V. T.; Santos, J. J.; Schlenvoigt, H.-P.; Baton, S. D.; Yahia, V.; Dipartimento di Fisica, Universit di Milano-Bicocca, Milano 20126 ; Honrubia, J. J.; Beg, F. N.; Chawla, S.; Jarrot, L. C.; Benocci, R.; Volpe, L.; and others

    2014-03-15

    We present results on laser-driven relativistic electron beam propagation through aluminum samples, which are either solid and cold or compressed and heated by laser-induced shock. A full numerical description of fast electron generation and transport is found to reproduce the experimental absolute K{sub ?} yield and spot size measurements for varying target thicknesses, and to sequentially quantify the collisional and resistive electron stopping powers. The results demonstrate that both stopping mechanisms are enhanced in compressed Al samples and are attributed to the increase in the medium density and resistivity, respectively. For the achieved time- and space-averaged electronic current density, ?j{sub h}??810{sup 10}?A/cm{sup 2} in the samples, the collisional and resistive stopping powers in warm and compressed Al are estimated to be 1.5?keV/?m and 0.8?keV/?m, respectively. By contrast, for cold and solid Al, the corresponding estimated values are 1.1?keV/?m and 0.6?keV/?m. Prospective numerical simulations involving higher j{sub h} show that the resistive stopping power can reach the same level as the collisional one. In addition to the effects of compression, the effect of the transient behavior of the resistivity of Al during relativistic electron beam transport becomes progressively more dominant, and for a significantly high current density, j{sub h}?10{sup 12}?A/cm{sup 2}, cancels the difference in the electron resistive stopping power (or the total stopping power in units of areal density) between solid and compressed samples. Analytical calculations extend the analysis up to j{sub h}=10{sup 14}?A/cm{sup 2} (representative of the full-scale fast ignition scenario of inertial confinement fusion), where a very rapid transition to the Spitzer resistivity regime saturates the resistive stopping power, averaged over the electron beam duration, to values of ?1?keV/?m.

  18. Warm Dense Crystallography: Digging Deeper into WDM

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

    Department of Energy Want a Tax Credit for a Small Wind System? Be Sure It's Certified! Want a Tax Credit for a Small Wind System? Be Sure It's Certified! August 3, 2015 - 3:54pm Addthis A small wind turbine can produce enough energy to cover the electricity costs of the average American home. | Photo from Bergey Windpower Co., Inc.; NREL 13830 A small wind turbine can produce enough energy to cover the electricity costs of the average American home. | Photo from Bergey Windpower Co., Inc.;

  19. Dynamic compression of dense oxide (Gd3Ga5O12) from 0.4 to 2.6 TPa: Universal Hugoniot of fluid metals

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

    Ozaki, N.; Nellis, W. J.; Mashimo, T.; Ramzan, M.; Ahuja, R.; Kaewmaraya, T.; Kimura, T.; Knudson, M.; Miyanishi, K.; Sakawa, Y.; et al

    2016-05-19

    Materials at high pressures and temperatures are of great current interest for warm dense matter physics, planetary sciences, and inertial fusion energy research. Shock-compression equation-of-state data and optical reflectivities of the fluid dense oxide, Gd3Ga5O12 (GGG), were measured at extremely high pressures up to 2.6 TPa (26 Mbar) generated by high-power laser irradiation and magnetically-driven hypervelocity impacts. Above 0.75 TPa, the GGG Hugoniot data approach/reach a universal linear line of fluid metals, and the optical reflectivity most likely reaches a constant value indicating that GGG undergoes a crossover from fluid semiconductor to poor metal with minimum metallic conductivity (MMC). Thesemore » results suggest that most fluid compounds, e.g., strong planetary oxides, reach a common state on the universal Hugoniot of fluid metals (UHFM) with MMC at sufficiently extreme pressures and temperatures. Lastly, the systematic behaviors of warm dense fluid would be useful benchmarks for developing theoretical equation-of-state and transport models in the warm dense matter regime in determining computational predictions.« less

  20. A Seemingly Simple Task: Filling a Solenoid Volume in Vacuum with Dense Plasma

    SciTech Connect (OSTI)

    Anders, Andre; Kauffeldt, Marina; Roy, Prabir; Oks, Efim

    2010-06-24

    Space-charge neutralization of a pulsed, high-current ion beam is required to compress and focus the beam on a target for warm dense matter physics or heavy ion fusion experiments. We described attempts to produce dense plasma in and near the final focusing solenoid through which the ion beam travels, thereby providing an opportunity for the beam to acquire the necessary charge-compensating electrons. Among the options are plasma injection from four pulsed vacuum arc sources located outside the solenoid, and using a high current (> 4 kA) pulsed vacuum arc plasma from a ring cathode near the edge of the solenoid. The plasma distribution is characterized by photographic means and by an array of movable Langmuir probes. The plasma is produced at several cathode spots distributed azimuthally on the ring cathode. Beam neutralization and compression are accomplished, though issues of density, uniformity, and pulse-to-pulse reproducibly remain to be solved.

  1. Dense Metal Plasma in a Solenoid for Ion Beam Neutralization

    SciTech Connect (OSTI)

    Anders, Andre; Kauffeldt, Marina; Oks, Efim M.; Roy, Prabir K.

    2010-10-30

    Space-charge neutralization is required to compress and focus a pulsed, high-current ion beam on a target for warm dense matter physics or heavy ion fusion experiments. We described approaches to produce dense plasma in and near the final focusing solenoid through which the ion beam travels, thereby providing an opportunity for the beam to acquire the necessary space-charge compensating electrons. Among the options are plasma injection from pulsed vacuum arc sources located outside the solenoid, and using a high current (> 4 kA) pulsed vacuum arc plasma from a ring cathode near the edge of the solenoid. The plasma distribution is characterized by photographic means, by an array of movable Langmuir probes, by a small single probe, and by evaluating Stark broadening of the Balmer H beta spectral line. In the main approach described here, the plasma is produced at several cathode spots distributed azimuthally on the ring cathode. It is shown that the plasma is essentially hollow, as determined by the structure of the magnetic field, though the plasma density exceeds 1014 cm-3 in practically all zones of the solenoid volume if the ring electrode is placed a few centimeters off the center of the solenoid. The plasma is non-uniform and fluctuating, however, since its density exceeds the ion beam density it is believed that this approach could provide a practical solution to the space charge neutralization challenge.

  2. Probing warm-dense Silica with LCLS and betatron radiation

    SciTech Connect (OSTI)

    Kotick, Jordan

    2015-08-27

    In this paper, a study of Silica is presented using a novel X-ray probe. The value of this X-ray source will be clearly defined, and diagnostic results will be presented.

  3. Self-similar expansion of a warm dense plasma

    SciTech Connect (OSTI)

    Djebli, Mourad; Moslem, Waleed M.

    2013-07-15

    The properties of an expanding plasma composed of degenerate electron fluid and non-degenerate ions are studied. For our purposes, we use fluid equations for ions together with the electron momentum equation that include quantum forces (e.g., the quantum statistical pressure, forces due to the electron-exchange and electron correlations effects) and the quasi-neutrality condition. The governing equation is written in a tractable form by using a self-similar transformation. Numerical results for typical beryllium plasma parameters revealed that, during the expansion, the ion acoustic speed decreases for both isothermal and adiabatic ion pressure. When compared with classical hydrodynamic plasma expansion model, the electrons and ions are found to initially escape faster in vacuum creating thus an intense electric field that accelerates most of the particles into the vacuum ahead of the plasma expansion. The relevancy of the present model to beryllium plasma produced by a femto-second laser is highlighted.

  4. Quantum dense key distribution

    SciTech Connect (OSTI)

    Degiovanni, I.P.; Ruo Berchera, I.; Castelletto, S.; Rastello, M.L.; Bovino, F.A.; Colla, A.M.; Castagnoli, G.

    2004-03-01

    This paper proposes a protocol for quantum dense key distribution. This protocol embeds the benefits of a quantum dense coding and a quantum key distribution and is able to generate shared secret keys four times more efficiently than the Bennet-Brassard 1984 protocol. We hereinafter prove the security of this scheme against individual eavesdropping attacks, and we present preliminary experimental results, showing its feasibility.

  5. Coalescence preference in densely packed microbubbles

    SciTech Connect (OSTI)

    Kim, Yeseul; Lim, Su Jin; Gim, Bopil; Weon, Byung Mook

    2015-01-13

    A bubble merged from two parent bubbles with different size tends to be placed closer to the larger parent. This phenomenon is known as the coalescence preference. Here we demonstrate that the coalescence preference can be blocked inside a densely packed cluster of bubbles. We utilized high-speed high-resolution X-ray microscopy to clearly visualize individual coalescence events inside densely packed microbubbles with a local packing fraction of ~40%. Thus, the surface energy release theory predicts an exponent of 5 in a relation between the relative coalescence position and the parent size ratio, whereas our observation for coalescence in densely packed microbubbles shows a different exponent of 2. We believe that this result would be important to understand the reality of coalescence dynamics in a variety of packing situations of soft matter.

  6. Coalescence preference in densely packed microbubbles

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

    Kim, Yeseul; Lim, Su Jin; Gim, Bopil; Weon, Byung Mook

    2015-01-13

    A bubble merged from two parent bubbles with different size tends to be placed closer to the larger parent. This phenomenon is known as the coalescence preference. Here we demonstrate that the coalescence preference can be blocked inside a densely packed cluster of bubbles. We utilized high-speed high-resolution X-ray microscopy to clearly visualize individual coalescence events inside densely packed microbubbles with a local packing fraction of ~40%. Thus, the surface energy release theory predicts an exponent of 5 in a relation between the relative coalescence position and the parent size ratio, whereas our observation for coalescence in densely packed microbubblesmore » shows a different exponent of 2. We believe that this result would be important to understand the reality of coalescence dynamics in a variety of packing situations of soft matter.« less

  7. Dense gas-compatible enzymes

    DOE Patents [OSTI]

    Kao, Fu-jung; Laintz, Kenneth E.; Sawan, Samuel P.; Sivils, L. Dale; Spall, W. Dale

    1998-07-21

    An enzymatic reaction system including a modified enzyme, and a dense gas system; modified enzymes; and methods of reacting modified enzymes in a dense gas system or liquid carbon dioxide.

  8. ARM - Global Warming

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

    Barrow, Alaska Tropical Western Pacific Site Tours Contacts Students Study Hall About ARM Global Warming FAQ Just for Fun Meet our Friends Cool Sites Teachers Teachers' Toolbox ...

  9. Kubo–Greenwood approach to conductivity in dense plasmas with average atom models

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

    Starrett, C. E.

    2016-06-01

    In this study, a new formulation of the Kubo–Greenwood conductivity for average atom models is given. The new formulation improves upon previous treatments by explicitly including the ionic-structure factor. Calculations based on this new expression lead to much improved agreement with ab initio results for DC conductivity of warm dense hydrogen and beryllium, and for thermal conductivity of hydrogen. We also give and test a slightly modified Ziman–Evans formula for the resistivity that includes a non-free electron density of states, thus removing an ambiguity in the original Ziman–Evans formula. Again, results based on this expression are in good agreement withmore » ab initio simulations for warm dense beryllium and hydrogen. However, for both these expressions, calculations of the electrical conductivity of warm dense aluminum lead to poor agreement at low temperatures compared to ab initio simulations.« less

  10. Confederated Tribes of Warm Springs - Biomass Project

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

    05 June 2005 A Case Study: A Case Study: Warm Springs Warm Springs Cal Mukumoto Cal Mukumoto Warm Springs Forest Warm Springs Forest Products Industries Products Industries Warm Springs Indian Warm Springs Indian Reservation of Oregon Reservation of Oregon Warm Springs Forest Warm Springs Forest Products Industries (WSFPI) Products Industries (WSFPI) Enterprise of the Confederated Enterprise of the Confederated Tribes of the Warm Springs Tribes of the Warm Springs Reservation of Oregon

  11. Collaborative Research: Neutrinos and Nucleosynthesis in Hot and Dense Matter

    SciTech Connect (OSTI)

    Alford, Mark

    2015-05-31

    The Topical Collaboration funded one of Prof. Alford's graduate students, Jun (Sophia) Han, by providing 75% of her support. The work reported here was wholly or partly supported by the Topical Collaboration. Additional support, e.g. for postdoc Kai Schwenzer, came from Nuclear Theory grant #DE-FG02-05ER41375.

  12. Distinct optical properties of relativistically degenerate matter

    SciTech Connect (OSTI)

    Akbari-Moghanjoughi, M.

    2014-06-15

    In this paper, we use the collisional quantum magnetohydrodynamic (CQMHD) model to derive the transverse dielectric function of a relativistically degenerate electron fluid and investigate various optical parameters, such as the complex refractive index, the reflection and absorption coefficients, the skin-depth and optical conductivity. In this model we take into accounts effects of many parameters such as the atomic-number of the constituent ions, the electron exchange, electron diffraction effect and the electron-ion collisions. Study of the optical parameters in the solid-density, the warm-dense-matter, the big-planetary core, and the compact star number-density regimes reveals that there are distinct differences between optical characteristics of the latter and the former cases due to the fundamental effects of the relativistic degeneracy and other quantum mechanisms. It is found that in the relativistic degeneracy plasma regime, such as found in white-dwarfs and neutron star crusts, matter possess a much sharper and well-defined step-like reflection edge beyond the x-ray electromagnetic spectrum, including some part of gamma-ray frequencies. It is also remarked that the magnetic field intensity only significantly affects the plasma reflectivity in the lower number-density regime, rather than the high density limit. Current investigation confirms the profound effect of relativistic degeneracy on optical characteristics of matter and can provide an important plasma diagnostic tool for studying the physical processes within the wide scope of quantum plasma regimes be it the solid-density, inertial-confined, or astrophysical compact stars.

  13. ARM - What Causes Global Warming?

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

    ThinkersWhat Causes Global Warming? Outreach Home Room News Publications Traditional Knowledge Kiosks Barrow, Alaska Tropical Western Pacific Site Tours Contacts Students Study Hall About ARM Global Warming FAQ Just for Fun Meet our Friends Cool Sites Teachers Teachers' Toolbox Lesson Plans What Causes Global Warming? What is the basis for the predictions concerning global warming? There are several gases in the air, collectively called greenhouse gases, that trap the infrared radiation emitted

  14. Dense, finely, grained composite materials

    DOE Patents [OSTI]

    Dunmead, Stephen D. (Davis, CA); Holt, Joseph B. (San Jose, CA); Kingman, Donald D. (Danville, CA); Munir, Zuhair A. (Davis, CA)

    1990-01-01

    Dense, finely grained composite materials comprising one or more ceramic phase or phase and one or more metallic and/or intermetallic phase or phases are produced by combustion synthesis. Spherical ceramic grains are homogeneously dispersed within the matrix. Methods are provided, which include the step of applying mechanical pressure during or immediately after ignition, by which the microstructures in the resulting composites can be controllably selected.

  15. Global warming from HFC

    SciTech Connect (OSTI)

    Johnson, E.

    1998-11-01

    Using a variety of public sources, a computer model of hydrofluorocarbon (HFC) refrigerant emissions in the UK has been developed. This model has been used to estimate and project emissions in 2010 under three types of scenarios: (1) business as usual; (2) voluntary agreements to reduce refrigerant leakage; and (3) comprehensive regulations to reduce refrigerant leakage. This resulting forecast is that UK emissions of HFC refrigerants in 2010 will account for 2% to 4% of the UK`s 1990 baseline global warming contribution.

  16. ARM - What is Global Warming?

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

    is Global Warming? Outreach Home Room News Publications Traditional Knowledge Kiosks Barrow, Alaska Tropical Western Pacific Site Tours Contacts Students Study Hall About ARM Global Warming FAQ Just for Fun Meet our Friends Cool Sites Teachers Teachers' Toolbox Lesson Plans What is Global Warming? Our earth's average temperature stays pretty much the same from year to year. Sometimes it gets very cold in the winter and very hot in the summer where you live. And some years may be a little hotter

  17. ARM - What is Global Warming?

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

    is Global Warming? Outreach Home Room News Publications Traditional Knowledge Kiosks Barrow, Alaska Tropical Western Pacific Site Tours Contacts Students Study Hall About ARM Global Warming FAQ Just for Fun Meet our Friends Cool Sites Teachers Teachers' Toolbox Lesson Plans What is Global Warming? The surface temperature of each of the planets in our solar system depends on a process called the heat budget. This budget, like any other type of budget, remains balanced if the amount (of energy)

  18. ARM - Lesson Plans: Global Warming

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

    Global Warming Outreach Home Room News Publications Traditional Knowledge Kiosks Barrow, Alaska Tropical Western Pacific Site Tours Contacts Students Study Hall About ARM Global ...

  19. New experimental platform to study high density laser-compressed matter

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

    Doppner, T.; LePape, S.; Ma, T.; Pak, A.; Gauthier, M.; Fletcher, L. B.; Ravasio, A.; Galtier, E.; Gamboa, E. J.; Granados, E.; et al

    2014-09-26

    We have developed a new experimental platform at the Linac Coherent Light Source (LCLS) which combines simultaneous angularly and spectrally resolved x-ray scatteringmeasurements. This technique offers a new insights on the structural and thermodynamic properties of warm dense matter. The < 50 fs temporal duration of the x-ray pulse provides near instantaneous snapshots of the dynamics of the compression. We present a proof of principle experiment for this platform to characterize a shock-compressed plastic foil. We observe the disappearance of the plastic semi-crystal structure and the formation of a compressed liquid ion-ion correlation peak. As a result, the plasma parametersmore » of shock-compressed plastic can be measured as well, but requires an averaging over a few tens of shots.« less

  20. Uniformly dense polymeric foam body

    DOE Patents [OSTI]

    Whinnery, Jr., Leroy

    2003-07-15

    A method for providing a uniformly dense polymer foam body having a density between about 0.013 g/cm.sup.3 to about 0.5 g/cm.sup.3 is disclosed. The method utilizes a thermally expandable polymer microsphere material wherein some of the microspheres are unexpanded and some are only partially expanded. It is shown that by mixing the two types of materials in appropriate ratios to achieve the desired bulk final density, filling a mold with this mixture so as to displace all or essentially all of the internal volume of the mold, heating the mold for a predetermined interval at a temperature above about 130.degree. C., and then cooling the mold to a temperature below 80.degree. C. the molded part achieves a bulk density which varies by less then about .+-.6% everywhere throughout the part volume.

  1. Matter under extreme conditions experiments at the Linac Coherent Light Source

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

    Glenzer, S. H.; Fletcher, L. B.; Galtier, E.; Nagler, B.; Alonso-Mori, R.; Barbrel, B.; Brown, S. B.; Chapman, D. A.; Chen, Z.; Curry, C. B.; et al

    2016-04-22

    The matter in extreme conditions end station at the Linac Coherent Light Source (LCLS) is a new tool enabling accurate pump–probe measurements for studying the physical properties of matter in the high-energy density (HED) physics regime. This instrument combines the world's brightest x-ray source, the LCLS x-ray beam, with high-power lasers consisting of two nanosecond Nd:glass laser beams and one short-pulse Ti:sapphire laser. Moreover, these lasers produce short-lived states of matter with high pressures, high temperatures or high densities with properties that are important for applications in nuclear fusion research, laboratory astrophysics and the development of intense radiation sources. Inmore » the first experiments, we have performed highly accurate x-ray diffraction and x-ray Thomson scattering measurements on shock-compressed matter resolving the transition from compressed solid matter to a co-existence regime and into the warm dense matter state. These complex charged-particle systems are dominated by strong correlations and quantum effects. They exist in planetary interiors and laboratory experiments, e.g., during high-power laser interactions with solids or the compression phase of inertial confinement fusion implosions. Applying record peak brightness x-rays resolves the ionic interactions at atomic (Ångstrom) scale lengths and measure the static structure factor, which is a key quantity for determining equation of state data and important transport coefficients. Simultaneously, spectrally resolved measurements of plasmon features provide dynamic structure factor information that yield temperature and density with unprecedented precision at micron-scale resolution in dynamic compression experiments. Likewise, these studies have demonstrated our ability to measure fundamental thermodynamic properties that determine the state of matter in the HED physics regime.« less

  2. Exploring Mbar shock conditions and isochorically heated aluminum at the Matter in Extreme Conditions end station of the Linac Coherent Light Source

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

    Doppner, T.; LePape, S.; Ma, T.; Pak, A.; Turnbull, D.; Fletcher, L. B.; Lee, H. J.; Galtier, E.; Nagler, B.; Gauthier, M.; et al

    2014-08-11

    Recent experiments performed at the Matter in Extreme Conditions end station of the Linac Coherent Light Source (LCLS) have demonstrated the first spectrally resolved measurements of plasmons from isochorically heated aluminum. The experiments have been performed using a seeded 8-keV x-ray laser beam as a pump and probe to both volumetrically heat and scatterx-rays from aluminum. Collective x-ray Thomson scattering spectra show a well-resolved plasmon feature that is down-shifted in energy by 19 eV. In addition, Mbar shock pressures from laser-compressed aluminum foils using velocity interferometer system for any reflector have been measured. Furthermore, the combination of experiments fully demonstratesmore » the possibility to perform warm dense matter studies at the LCLS with unprecedented accuracy and precision.« less

  3. Military implications of global warming. Strategy research project

    SciTech Connect (OSTI)

    Greene, P.E.

    1999-05-20

    The 1998 National Security Strategy repeatedly cites global environmental issues as key to the long-term security of the United States. Similarly, US environmental issues also have important global implications. This paper analyzes current US Policy as it pertains to global warming and climate change. It discusses related economic factors and environmental concerns. It assesses current White House policy as it relates to the US military. It reviews the Department of Defense strategy for energy conservation and reduction of greenhouse gases. Finally, it offers recommendations and options for military involvement to reduce global warming. Global warming and other environmental issues are important to the US military. As the United States leadership in environmental matters encourages global stability, the US military will be able to focus more on readiness and on military training and operations.

  4. X-ray Thomson Scattering from Dense Plasmas

    SciTech Connect (OSTI)

    Glenzer, S

    2007-05-14

    Advances in the development of laser-produced x-ray sources have enabled a new class of high-energy density physics experiments. Powerful narrow-bandwidth x rays penetrate through short-lived hot dense states of matter and probe the physical properties with spectrally resolved x-ray scattering. Experiments from isochorically-heated plasmas with electron densities in the range of solid density and above have been demonstrated allowing for the first time exploration of the microscopic properties of dense matter regime close to strongly-coupled and Fermi degenerate conditions. Backscatter measurements have accessed the non-collective Compton scattering regime, which provides accurate diagnostic information on the temperature, density and ionization states. The forward scattering spectrum has been shown to measure the collective plasmon oscillations. Besides extracting the standard plasma parameters, density and temperature, forward scattering yields new observables such as a direct measure of collisions, quantum effects and detailed balance. In this talk, we will discuss new results important for applications of this technique for novel experiments in a wide range of research areas such as inertial confinement fusion, radiation-hydrodynamics, material science, and laboratory astrophysics.

  5. Solenoid transport of a heavy ion beam for warm dense matterstudies and inertial confinement fusion

    SciTech Connect (OSTI)

    Armijo, Julien

    2006-10-01

    From February to July 2006, I have been doing research as a guest at Lawrence Berkeley National Laboratory (LBNL), in the Heavy Ion Fusion group. This internship, which counts as one semester in my master's program in France, I was very pleased to do it in a field that I consider has the beauty of fundamental physics, and at the same time the special appeal of a quest for a long-term and environmentally-respectful energy source. During my stay at LBNL, I have been involved in three projects, all of them related to Neutralized Drift Compression Experiment (NDCX). The first one, experimental and analytical, has consisted in measuring the effects of the eddy currents induced by the pulsed magnets in the conducting plates of the source and diagnostic chambers of the Solenoid Transport Experiment (STX, which is a subset of NDCX). We have modeled the effect and run finite-element simulations that have reproduced the perturbation to the field. Then, we have modified WARP, the Particle-In-Cell code used to model the whole experiment, in order to import realistic fields including the eddy current effects and some details of each magnet. The second project has been to take part in a campaign of WARP simulations of the same experiment to understand the leakage of electrons that was observed in the experiment as a consequence to some diagnostics and the failure of the electrostatic electron trap. The simulations have shown qualitative agreement with the measured phenomena, but are still in progress. The third project, rather theoretical, has been related to the upcoming target experiment of a thin aluminum foil heated by a beam to the 1-eV range. At the beginning I helped by analyzing simulations of the hydrodynamic expansion and cooling of the heated material. But, progressively, my work turned into making estimates for the nature of the liquid/vapor two-phase flow. In particular, I have been working on criteria and models to predict the formation of droplets, their size, and their partial or total evaporation in the expanding flow.

  6. Warm Springs Greenhouses Greenhouse Low Temperature Geothermal...

    Open Energy Info (EERE)

    Warm Springs Greenhouses Greenhouse Low Temperature Geothermal Facility Jump to: navigation, search Name Warm Springs Greenhouses Greenhouse Low Temperature Geothermal Facility...

  7. ARM - What Causes Global Warming?

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

    Teachers' Toolbox Lesson Plans What Causes Global Warming? On earth we get energy from the sun's light. As you know, it gets hot outside if the sun is shining brightly on a summer ...

  8. Global Warming and Human Health

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

    American Geophysical Union Global Warming and Human Health WHEN: Jul 27, 2015 5:30 PM - ... Event Description The main reason we are concerned about human-induced climate change is ...

  9. Rapid heating of materials using high power lasers

    SciTech Connect (OSTI)

    Bang, Woosuk

    2015-12-01

    Presentation covering uniform & rapid heating of a target, study of warm dense matter, study of nuclear fusion reactions

  10. METHOD OF PRODUCING DENSE CONSOLIDATED METALLIC REGULUS

    DOE Patents [OSTI]

    Magel, T.T.

    1959-08-11

    A methcd is presented for reducing dense metal compositions while simultaneously separating impurities from the reduced dense metal and casting the reduced parified dense metal, such as uranium, into well consolidated metal ingots. The reduction is accomplished by heating the dense metallic salt in the presence of a reducing agent, such as an alkali metal or alkaline earth metal in a bomb type reacting chamber, while applying centrifugal force on the reacting materials. Separation of the metal from the impurities is accomplished essentially by the incorporation of a constricted passageway at the vertex of a conical reacting chamber which is in direct communication with a collecting chamber. When a centrifugal force is applled to the molten metal and slag from the reduction in a direction collinear with the axis of the constricted passage, the dense molten metal is forced therethrough while the less dense slag is retained within the reaction chamber, resulting in a simultaneous separation of the reduced molten metal from the slag and a compacting of the reduced metal in a homogeneous mass.

  11. Cosmic Rays and Global Warming

    SciTech Connect (OSTI)

    Sloan, T.; Wolfendale, A. W.

    2008-01-24

    Some workers have claimed that the observed temporal correlations of (low level) terrestrial cloud cover with the cosmic ray intensity changes, due to solar modulation, are causal. The possibility arises, therefore, of a connection between cosmic rays and Global Warming. If true, the implications would be very great. We have examined this claim in some detail. So far, we have not found any evidence in support and so our conclusions are to doubt it. From the absence of corroborative evidence we estimate that less than 15% at the 95% confidence level, of the 11-year cycle warming variations are due to cosmic rays and less than 2% of the warming over the last 43 years is due to this cause. The origin of the correlation itself is probably the cycle of solar irradiance although there is, as yet, no certainty.

  12. Implementation and Re nement of a Comprehensive Model for Dense...

    Office of Scientific and Technical Information (OSTI)

    Model for Dense Granular Flows Dense granular ows are ubiquitous in both natural and industrial processes. They manifest three di erent ow regimes, each exhibiting its own...

  13. Computer Simulations Indicate Calcium Carbonate Has a Dense Liquid...

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

    Computer Simulations Indicate Calcium Carbonate Has a Dense Liquid Phase Computer Simulations Indicate Calcium Carbonate Has a Dense Liquid Phase Berkeley Lab research could help...

  14. Warming up to solar energy

    SciTech Connect (OSTI)

    Biondo, B.

    1996-07-01

    Increasingly alarmed by threats to their financial security posed by an escalating number of weather-related catastrophes, major insurance companaies, particularly those in Europe and Asia, are starting to support a variety of measures that would slowe the production of grenhouse gases worlwide. As the insurance and banking industries turn their attention to global warming, investments in solar energy take on growing appeal.

  15. Microclimatic performance of a free-air warming and CO₂ enrichment experiment in windy Wyoming, USA

    SciTech Connect (OSTI)

    LeCain, Daniel; Smith, David; Morgan, Jack; Kimball, Bruce A.; Pendall, Elise; Miglietta, Franco; Liang, Wenju

    2015-02-06

    In order to plan for global changing climate experiments are being conducted in many countries, but few have monitored the effects of the climate change treatments (warming, elevated CO₂) on the experimental plot microclimate. During three years of an eight year study with year-round feedback-controlled infra-red heater warming (1.5/3.0°C day/night) and growing season free-air CO₂ enrichment (600 ppm) in the mixed-grass prairie of Wyoming, USA, we monitored soil, leaf, canopy-air, above-canopy-air temperatures and relative humidity of control and treated experimental plots and evaluated ecologically important temperature differentials. Leaves were warmed somewhat less than the target settings (1.1 & 1.5°C day/night) but soil was warmed more creating an average that matched the target settings extremely well both during the day and night plus the summer and winter. The site typically has about 50% bare or litter covered soil, therefore soil heat transfer is more critical than in dense canopy ecosystems. The Wyoming site commonly has strong winds (5 ms⁻¹ average) and significant daily and seasonal temperature fluctuations (as much as 30°C daily) but the warming system was nearly always able to maintain the set temperatures regardless of abiotic variation. The within canopy-air was only slightly warmed and above canopy-air was not warmed by the system, therefore convective warming was minor. Elevated CO₂ had no direct effect nor interaction with the warming treatment on microclimate. Relative humidity within the plant canopy was only slightly reduced by warming. Soil water content was reduced by warming but increased by elevated CO₂. This study demonstrates the importance of monitoring the microclimate in manipulative field global change experiments so that critical physiological and ecological conclusions can be determined. Highly variable energy demand fluctuations showed that passive IR heater warming systems will not maintain desired warming for much

  16. Microclimatic performance of a free-air warming and CO₂ enrichment experiment in windy Wyoming, USA

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

    LeCain, Daniel; Smith, David; Morgan, Jack; Kimball, Bruce A.; Pendall, Elise; Miglietta, Franco; Liang, Wenju

    2015-02-06

    In order to plan for global changing climate experiments are being conducted in many countries, but few have monitored the effects of the climate change treatments (warming, elevated CO₂) on the experimental plot microclimate. During three years of an eight year study with year-round feedback-controlled infra-red heater warming (1.5/3.0°C day/night) and growing season free-air CO₂ enrichment (600 ppm) in the mixed-grass prairie of Wyoming, USA, we monitored soil, leaf, canopy-air, above-canopy-air temperatures and relative humidity of control and treated experimental plots and evaluated ecologically important temperature differentials. Leaves were warmed somewhat less than the target settings (1.1 & 1.5°C day/night)more » but soil was warmed more creating an average that matched the target settings extremely well both during the day and night plus the summer and winter. The site typically has about 50% bare or litter covered soil, therefore soil heat transfer is more critical than in dense canopy ecosystems. The Wyoming site commonly has strong winds (5 ms⁻¹ average) and significant daily and seasonal temperature fluctuations (as much as 30°C daily) but the warming system was nearly always able to maintain the set temperatures regardless of abiotic variation. The within canopy-air was only slightly warmed and above canopy-air was not warmed by the system, therefore convective warming was minor. Elevated CO₂ had no direct effect nor interaction with the warming treatment on microclimate. Relative humidity within the plant canopy was only slightly reduced by warming. Soil water content was reduced by warming but increased by elevated CO₂. This study demonstrates the importance of monitoring the microclimate in manipulative field global change experiments so that critical physiological and ecological conclusions can be determined. Highly variable energy demand fluctuations showed that passive IR heater warming systems will not maintain desired warming

  17. Warming trends: Adapting to nonlinear change

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

    Jonko, Alexandra K.

    2015-01-28

    As atmospheric carbon dioxide concentrations rise, some regions are expected to warm more than others. Research suggests that whether warming will intensify or slow down over time also depends on location.

  18. Hydrological consequences of global warming

    SciTech Connect (OSTI)

    Miller, Norman L.

    2009-06-01

    The 2007 Intergovernmental Panel for Climate Change indicates there is strong evidence that the atmospheric concentration of carbon dioxide far exceeds the natural range over the last 650,000 years, and this recent warming of the climate system is unequivocal, resulting in more frequent extreme precipitation events, earlier snowmelt runoff, increased winter flood likelihoods, increased and widespread melting of snow and ice, longer and more widespread droughts, and rising sea level. The effects of recent warming has been well documented and climate model projections indicate a range of hydrological impacts with likely to very likely probabilities (67 to 99 percent) of occurring with significant to severe consequences in response to a warmer lower atmosphere with an accelerating hydrologic cycle.

  19. Dark Matters

    ScienceCinema (OSTI)

    Joseph Silk

    2010-01-08

    One of the greatest mysteries in the cosmos is that it is mostly dark.  Astronomers and particle physicists today are seeking to unravel the nature of this mysterious, but pervasive dark matter which has profoundly influenced the formation of structure in the universe.  I will describe the complex interplay between galaxy formation and dark matter detectability and review recent attempts to measure particle dark matter by direct and indirect means.

  20. Preparation of a dense, polycrystalline ceramic structure

    DOE Patents [OSTI]

    Cooley, Jason; Chen, Ching-Fong; Alexander, David

    2010-12-07

    Ceramic nanopowder was sealed inside a metal container under a vacuum. The sealed evacuated container was forced through a severe deformation channel at an elevated temperature below the melting point of the ceramic nanopowder. The result was a dense nanocrystalline ceramic structure inside the metal container.

  1. Dense high temperature ceramic oxide superconductors

    DOE Patents [OSTI]

    Landingham, R.L.

    1993-10-12

    Dense superconducting ceramic oxide articles of manufacture and methods for producing these articles are described. Generally these articles are produced by first processing these superconducting oxides by ceramic processing techniques to optimize materials properties, followed by reestablishing the superconducting state in a desired portion of the ceramic oxide composite.

  2. Dense high temperature ceramic oxide superconductors

    DOE Patents [OSTI]

    Landingham, Richard L.

    1993-01-01

    Dense superconducting ceramic oxide articles of manufacture and methods for producing these articles are described. Generally these articles are produced by first processing these superconducting oxides by ceramic processing techniques to optimize materials properties, followed by reestablishing the superconducting state in a desired portion of the ceramic oxide composite.

  3. Integrated assessment of global warming

    SciTech Connect (OSTI)

    Ott, K.O.

    1996-12-31

    The anomalies of sea surface temperatures, which show a warming trend since the 1850s through the decade 1960/70 of {Delta}SST {approximately} 0.3 C, are complemented by changes of the ground surface temperature ({Delta}GST). The global surface temperature change, based on these data, allows an integrated assessment of the associated increase in black-body irradiance and a comparison with the enhanced greenhouse-gas back-scattering. Information on the GST history is obtained from unfolding analyses of underground temperature distributions measured in 90 boreholes in Alaskan permafrost and Canadian bedrock. These analyses show GST increases ({Delta}GST) since the 19th century through 1960/70 of 3 C on average, with standard deviations of +1.8 C and {minus}0.9 C on the high and low end respectively. The onset of the warming trend, which is uncertain in the GST data, is timed more accurately by detailed length records of large valley glaciers in the US and the Alps. Evaluation of the heat capacities and heat transfer indicates that the temperature response to an increase in radiative forcing must be much larger on land than on the sea. Conversely, the observed large ratio of {Delta}GST and {Delta}SST can only be explained by increased radiative forcing. From 1960/70 through the warmest decade on record, 1980/90, global {Delta}SST and {Delta}SAT have further increased to 0.6 C and 0.8 C respectively, But, the most recent GST data are not accurate enough to extend the comparison through 1990. Calculation of the increase of radiative forcing from back-scattering of greenhouse gases for 1850 to 1970 yields 1.3 W/cm{sup 2}. The increase in black-body irradiance from 3.6 C warming on land and 0.3 C on sea provides the required balance. The warming on land of 3.6 C is larger than the average value of 3.0 C, but well within the observed range.

  4. Structures for dense, crack free thin films

    DOE Patents [OSTI]

    Jacobson, Craig P.; Visco, Steven J.; De Jonghe, Lutgard C.

    2011-03-08

    The process described herein provides a simple and cost effective method for making crack free, high density thin ceramic film. The steps involve depositing a layer of a ceramic material on a porous or dense substrate. The deposited layer is compacted and then the resultant laminate is sintered to achieve a higher density than would have been possible without the pre-firing compaction step.

  5. Oxygen ion-conducting dense ceramic

    DOE Patents [OSTI]

    Balachandran, Uthamalingam; Kleefisch, Mark S.; Kobylinski, Thaddeus P.; Morissette, Sherry L.; Pei, Shiyou

    1998-01-01

    Preparation, structure, and properties of mixed metal oxide compositions and their uses are described. Mixed metal oxide compositions of the invention have stratified crystalline structure identifiable by means of powder X-ray diffraction patterns. In the form of dense ceramic membranes, the present compositions demonstrate an ability to separate oxygen selectively from a gaseous mixture containing oxygen and one or more other volatile components by means of ionic conductivities.

  6. Shear dispersion in dense granular flows

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

    Christov, Ivan C.; Stone, Howard A.

    2014-04-18

    We formulate and solve a model problem of dispersion of dense granular materials in rapid shear flow down an incline. The effective dispersivity of the depth-averaged concentration of the dispersing powder is shown to vary as the Péclet number squared, as in classical Taylor–Aris dispersion of molecular solutes. An extension to generic shear profiles is presented, and possible applications to industrial and geological granular flows are noted.

  7. Dark Matter

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

    Dark Matter Scientists are using the underground of the Waste Isolation Pilot Plant to try to solve the universe's major missing mass problem. He is enjoying his search They are searching for the presence of particles that may have mass but hardly interact with other matter. Based on observations of the relationships between mass and gravity and the speed of the stars and other cosmological systems, scientists believe that more than 90 percent of the universe's mass is "missing." A

  8. Global Warming Solutions Inc previously Southern Investments...

    Open Energy Info (EERE)

    Solutions Inc previously Southern Investments Inc Jump to: navigation, search Name: Global Warming Solutions Inc (previously Southern Investments Inc) Place: Houston, Texas...

  9. Nuclear energy output slows as climate warms

    SciTech Connect (OSTI)

    Kramer, David

    2014-06-01

    New reports from the Intergovernmental Panel on Climate Change and the US government say the window is closing for actions to avert the worst effects of warming.

  10. End Calorimeter Warm Tube Heater

    SciTech Connect (OSTI)

    Primdahl, K.; /Fermilab

    1991-08-06

    The Tevatron accelerator beam tube must pass through the End Calorimeter cryostats of the D-Zero Collider Detector. Furthermore, the End Calorimeter cryostats must be allowed to roll back forty inches without interruption of the vacuum system; hence, the Tev tube must slide through the End Calorimeter cryostat as it is rolled back. The Tev pass through the End Calorimeter can actually be thought of as a cluster of concentric tubes: Tev tube, warm (vacuum vessel) tube, IS layers of superinsulation, cold tube (argon vessel), and Inner Hadronic center support tube. M. Foley generated an ANSYS model to study the heat load. to the cryostat. during collider physics studies; that is, without operation of the heater. A sketch of the model is included in the appendix. The vacuum space and superinsulation was modeled as a thermal solid, with conductivity derived from tests performed at Fermilab. An additional estimate was done. by this author, using data supplied by NR-2. a superinsulation manufacturer. The ANSYS result and hand calculation are in close agreement. The ANSYS model was modified. by this author. to incorporate the effect of the heater. Whereas the earlier model studied steady state operation only. the revised model considers the heater-off steady state mode as the initial condition. then performs a transient analysis with a final load step for time tending towards infinity. Results show the thermal gradient as a function of time and applied voltage. It should be noted that M. Foley's model was generated for one half the warm tube. implying the tube to be symmetric. In reality. the downstream connection (relative to the collision point) attachment to the vacuum shell is via several convolutions of a 0.020-inch wall bellows; hence. a nearly adiabatic boundary condition. Accordingly. the results reported in the table reflect extrapolation of the curves to the downstream end of the tube. Using results from the ANSYS analysis, that is, tube temperature and

  11. Electrical and thermal conductivities in dense plasmas

    SciTech Connect (OSTI)

    Faussurier, G. Blancard, C.; Combis, P.; Videau, L.

    2014-09-15

    Expressions for the electrical and thermal conductivities in dense plasmas are derived combining the Chester-Thellung-Kubo-Greenwood approach and the Kramers approximation. The infrared divergence is removed assuming a Drude-like behaviour. An analytical expression is obtained for the Lorenz number that interpolates between the cold solid-state and the hot plasma phases. An expression for the electrical resistivity is proposed using the Ziman-Evans formula, from which the thermal conductivity can be deduced using the analytical expression for the Lorenz number. The present method can be used to estimate electrical and thermal conductivities of mixtures. Comparisons with experiment and quantum molecular dynamics simulations are done.

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

    SciTech Connect (OSTI)

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

    2014-12-01

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

  13. Solids flow rate measurement in dense slurries

    SciTech Connect (OSTI)

    Porges, K.G.; Doss, E.D.

    1993-09-01

    Accurate and rapid flow rate measurement of solids in dense slurries remains an unsolved technical problem, with important industrial applications in chemical processing plants and long-distance solids conveyance. In a hostile two-phase medium, such a measurement calls for two independent parameter determinations, both by non-intrusive means. Typically, dense slurries tend to flow in laminar, non-Newtonian mode, eliminating most conventional means that usually rely on calibration (which becomes more difficult and costly for high pressure and temperature media). These issues are reviewed, and specific solutions are recommended in this report. Detailed calculations that lead to improved measuring device designs are presented for both bulk density and average velocity measurements. Cross-correlation, chosen here for the latter task, has long been too inaccurate for practical applications. The cause and the cure of this deficiency are discussed using theory-supported modeling. Fluid Mechanics are used to develop the velocity profiles of laminar non-Newtonian flow in a rectangular duct. This geometry uniquely allows the design of highly accurate `capacitive` devices and also lends itself to gamma transmission densitometry on an absolute basis. An absolute readout, though of less accuracy, is also available from a capacitive densitometer and a pair of capacitive sensors yields signals suitable for cross-correlation velocity measurement.

  14. Global warming, insurance losses and financial industry

    SciTech Connect (OSTI)

    Low, N.C.

    1996-12-31

    Global warming causes extremely bad weather in the near term. They have already caught the attention of the insurance industry, as they suffered massive losses in the last decade. Twenty-one out of the 25 largest catastrophes in the US, mainly in the form of hurricanes have occurred in the last decade. The insurance industry has reacted by taking the risk of global warming in decisions as to pricing and underwriting decisions. But they have yet to take a more active role in regulating the factors that contributes to global warming. How global warming can impact the financial industry and the modern economy is explored. Insurance and modern financial derivatives are key to the efficient functioning of the modern economy, without which the global economy can still function but will take a giant step backward. Any risk as global warming that causes economic surprises will hamper the efficient working of the financial market and the modern economy.

  15. Insulation Troubles: A Story of a House That Never Stayed Warm, Part 2 |

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

    Department of Energy 2 Insulation Troubles: A Story of a House That Never Stayed Warm, Part 2 November 10, 2015 - 4:37pm Addthis An insulated door was an easy upgrade from the steel cellar door that let cold air into our house. Photo by Elizabeth Spencer An insulated door was an easy upgrade from the steel cellar door that let cold air into our house. Photo by Elizabeth Spencer Our contractors layered radiant barriers with dense-pack insulation and sealed air vents. Photo by Elizabeth

  16. Development and Benchmarking of a Hybrid PIC Code For Dense Plasmas and Fast Ignition

    SciTech Connect (OSTI)

    Witherspoon, F. Douglas; Welch, Dale R.; Thompson, John R.; MacFarlane, Joeseph J.; Phillips, Michael W.; Bruner, Nicki; Mostrom, Chris; Thoma, Carsten; Clark, R. E.; Bogatu, Nick; Kim, Jin-Soo; Galkin, Sergei; Golovkin, Igor E.; Woodruff, P. R.; Wu, Linchun; Messer, Sarah J.

    2014-05-20

    Radiation processes play an important role in the study of both fast ignition and other inertial confinement schemes, such as plasma jet driven magneto-inertial fusion, both in their effect on energy balance, and in generating diagnostic signals. In the latter case, warm and hot dense matter may be produced by the convergence of a plasma shell formed by the merging of an assembly of high Mach number plasma jets. This innovative approach has the potential advantage of creating matter of high energy densities in voluminous amount compared with high power lasers or particle beams. An important application of this technology is as a plasma liner for the flux compression of magnetized plasma to create ultra-high magnetic fields and burning plasmas. HyperV Technologies Corp. has been developing plasma jet accelerator technology in both coaxial and linear railgun geometries to produce plasma jets of sufficient mass, density, and velocity to create such imploding plasma liners. An enabling tool for the development of this technology is the ability to model the plasma dynamics, not only in the accelerators themselves, but also in the resulting magnetized target plasma and within the merging/interacting plasma jets during transport to the target. Welch pioneered numerical modeling of such plasmas (including for fast ignition) using the LSP simulation code. Lsp is an electromagnetic, parallelized, plasma simulation code under development since 1995. It has a number of innovative features making it uniquely suitable for modeling high energy density plasmas including a hybrid fluid model for electrons that allows electrons in dense plasmas to be modeled with a kinetic or fluid treatment as appropriate. In addition to in-house use at Voss Scientific, several groups carrying out research in Fast Ignition (LLNL, SNL, UCSD, AWE (UK), and Imperial College (UK)) also use LSP. A collaborative team consisting of HyperV Technologies Corp., Voss Scientific LLC, FAR-TECH, Inc., Prism

  17. Oxygen ion-conducting dense ceramic

    DOE Patents [OSTI]

    Balachandran, Uthamalingam; Kleefisch, Mark S.; Kobylinski, Thaddeus P.; Morissette, Sherry L.; Pei, Shiyou

    1996-01-01

    Preparation, structure, and properties of mixed metal oxide compositions containing at least strontium, cobalt, iron and oxygen are described. The crystalline mixed metal oxide compositions of this invention have, for example, structure represented by Sr.sub..alpha. (Fe.sub.1-x Co.sub.x).sub..alpha.+.beta. O.sub..delta. where x is a number in a range from 0.01 to about 1, .alpha. is a number in a range from about 1 to about 4, .beta. is a number in a range upward from 0 to about 20, and .delta. is a number which renders the compound charge neutral, and wherein the composition has a non-perovskite structure. Use of the mixed metal oxides in dense ceramic membranes which exhibit oxygen ionic conductivity and selective oxygen separation, are described as well as their use in separation of oxygen from an oxygen-containing gaseous mixture.

  18. Oxygen ion-conducting dense ceramic

    DOE Patents [OSTI]

    Balachandran, Uthamalingam; Kleefisch, Mark S.; Kobylinski, Thaddeus P.; Morissette, Sherry L.; Pei, Shiyou

    1997-01-01

    Preparation, structure, and properties of mixed metal oxide compositions containing at least strontium, cobalt, iron and oxygen are described. The crystalline mixed metal oxide compositions of this invention have, for example, structure represented by Sr.sub..alpha. (Fe.sub.1-x Co.sub.x).sub..alpha.+.beta. O.sub..delta. where x is a number in a range from 0.01 to about 1, .alpha. is a number in a range from about 1 to about 4, .beta. is a number in a range upward from 0 to about 20, and .delta. is a number which renders the compound charge neutral, and wherein the composition has a non-perovskite structure. Use of the mixed metal oxides in dense ceramic membranes which exhibit oxygen ionic conductivity and selective oxygen separation, are described as well as their use in separation of oxygen from an oxygen-containing gaseous mixture.

  19. Computer Simulations Indicate Calcium Carbonate Has a Dense Liquid Phase

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

    Computer Simulations Indicate Calcium Carbonate Has a Dense Liquid Phase Computer Simulations Indicate Calcium Carbonate Has a Dense Liquid Phase Berkeley Lab research could help scientists predict how carbon is stored underground August 22, 2013 Dan Krotz 510-486-4019 dakrotz@lbl.gov red2.jpg Artistic rendition of liquid-liquid separation in a supersaturated calcium carbonate solution. New research suggests that a dense liquid phase (shown in red in the background and in full atomistic detail

  20. Femtosecond Population Inversion and Stimulated Emission of Dense...

    Office of Scientific and Technical Information (OSTI)

    Femtosecond Population Inversion and Stimulated Emission of Dense Dirac Fermions in Graphene Citation Details In-Document Search Title: Femtosecond Population Inversion and...

  1. Continuum modeling of diffusion and dispersion in dense granular...

    Office of Scientific and Technical Information (OSTI)

    Title: Continuum modeling of diffusion and dispersion in dense granular flows Authors: Christov, Ivan C 1 ; Stone, Howard A 2 + Show Author Affiliations Los Alamos National ...

  2. Solid State Processing of Fully Dense Anistropic Nanocomposition...

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

    Solid State Processing of Fully Dense Anistropic Nanocomposition Magnets Research Personnel Characterization The project proposes a new solid state processing technology which will...

  3. Wildfires may contribute more to global warming than previously...

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

    Wildfires may contribute more to global warming Wildfires may contribute more to global warming than previously predicted They suggest that fire emissions could contribute a lot...

  4. North Florida Global Warming Study Group | Open Energy Information

    Open Energy Info (EERE)

    Global Warming Study Group Jump to: navigation, search Name: North Florida Global Warming Study Group Address: 8342 Compass Rose Dr S Place: Jacksonville, Florida Zip: 32216 Year...

  5. Confederated Tribes of the Warm Springs Reservation- 2007 Wind Project

    Broader source: Energy.gov [DOE]

    Warm Springs Power and Water Enterprises (WSPWE) is a corporate entity owned by the Confederated Tribes of the Warm Springs Reservation, located in central Oregon.

  6. Warm Springs Resort Pool & Spa Low Temperature Geothermal Facility...

    Open Energy Info (EERE)

    Pool & Spa Low Temperature Geothermal Facility Jump to: navigation, search Name Warm Springs Resort Pool & Spa Low Temperature Geothermal Facility Facility Warm Springs Resort...

  7. Thermodynamic Evaluation of Low-Global Warming Potential Refrigerants...

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

    Credit: National Institute of Standards Thermodynamic Evaluation of Low-Global Warming Potential Refrigerants Research & Development Roadmap: Next-Generation Low Global Warming ...

  8. Wildfires may contribute more to global warming than previously...

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

    Wildfires may contribute more to global warming Wildfires may contribute more to global warming than previously predicted They suggest that fire emissions could contribute a lot ...

  9. Potential Effect of Pollutantn Emissions on Global Warming: First...

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

    Potential Effect of Pollutantn Emissions on Global Warming: First Comparisong Using External Costs on Urban Buses Potential Effect of Pollutantn Emissions on Global Warming: First ...

  10. Scientific American: "Tall Trees Sucked Dry by Global Warming...

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

    Scientific American: "Tall Trees Sucked Dry by Global Warming" Scientific American: "Tall Trees Sucked Dry by Global Warming" Climate change will challenge tall trees like ...

  11. Scientific American: "Tall Trees Sucked Dry by Global Warming...

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

    Scientific American: "Tall Trees Sucked Dry by Global Warming" June 7, 2015 Scientific American: "Tall Trees Sucked Dry by Global Warming" A well-known scientific principle ...

  12. Confederated Tribes of the Warm Springs Reservation- 2007 Project

    Broader source: Energy.gov [DOE]

    Warm Springs Power and Water Enterprises (WSPWE) is a corporate entity owned by the Confederated Tribes of the Warm Springs Reservation, located in central Oregon.

  13. Direct Imaging of Warm Extrasolar Planets (Technical Report)...

    Office of Scientific and Technical Information (OSTI)

    Technical Report: Direct Imaging of Warm Extrasolar Planets Citation Details In-Document ... companions to young stars, we can see thermal emission from planets that are still warm ...

  14. Global warming and nuclear power

    SciTech Connect (OSTI)

    Wood, L., LLNL

    1998-07-10

    -fold reduction might be attained. Even the first such halving of carbon intensivity of stationary-source energy production world-wide might permit continued slow power-demand growth in the highly developed countries and rapid development of the other 80% of the world, both without active governmental suppression of fossil fuel usage - while also stabilizing carbon input-rates into the Earth`s atmosphere. The second two-fold reduction might obviate most global warming concerns.

  15. Dense ceramic membranes for methane conversion

    SciTech Connect (OSTI)

    Balachandran, U.; Mieville, R.L.; Ma, B.; Udovich, C.A.

    1996-05-01

    This report focuses on a mechanism for oxygen transport through mixed- oxide conductors as used in dense ceramic membrane reactors for the partial oxidation of methane to syngas (CO and H{sub 2}). The in-situ separation of O{sub 2} from air by the membrane reactor saves the costly cryogenic separation step that is required in conventional syngas production. The mixed oxide of choice is SrCo{sub 0.5}FeO{sub x}, which exhibits high oxygen permeability and has been shown in previous studies to possess high stability in both oxidizing and reducing conditions; in addition, it can be readily formed into reactor configurations such as tubes. An understanding of the electrical properties and the defect dynamics in this material is essential and will help us to find the optimal operating conditions for the conversion reactor. In this paper, we discuss the conductivities of the SrFeCo{sub 0.5}O{sub x} system that are dependent on temperature and partial pressure of oxygen. Based on the experimental results, a defect model is proposed to explain the electrical properties of this system. The oxygen permeability of SrFeCo{sub 0.5}O{sub x} is estimated by using conductivity data and is compared with that obtained from methane conversion reaction.

  16. Interparticle interaction and transport processes in dense semiclassical plasmas

    SciTech Connect (OSTI)

    Baimbetov, F.B.; Giniyatova, Sh.G.

    2005-04-15

    On the basis of the density response formalism an expression for the pseudopotential of dense semiclassical plasma, which takes account of quantum-mechanical effects, local field corrections, and electronic screening effects is obtained. The static structure factors taking into account both local fields and quantum-mechanical effects are calculated. An electrical conductivity, thermal conductivity, and viscosity of dense semiclassical plasma are studied.

  17. Development of dense-phase pneumatic transport of coal

    SciTech Connect (OSTI)

    Horisaka, S.; Ikemiya, H.; Kajiwara, T.

    1996-12-31

    Dense phase pneumatic transport system has been developed to reduce entrained particles as is seen in the belt conveyor system. High mass flow rate and dense phase (Loading ratio = 50--100kg-coal/kg-N{sub 2}) transport has been achieved by applying this plug flow system to pneumatic conveying of coal (Average particle diameter = 2.5 mm).

  18. Confederated Tribes of Warm Springs - Geothermal Feasibility Study

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

    Water Enterprises Geothermal Power Development Feasibility Study Warm Springs Indian Reservation US Department of Energy Tribal Energy Program Review October 23-27 2006 Confederated Tribes of Warm Springs Warm Springs, Oregon Project Participants Project Participants * * Jim Manion, GM, Warm Springs Power & Water Ent. Jim Manion, GM, Warm Springs Power & Water Ent. * * David McClain, DW McClain Associates David McClain, DW McClain Associates * * GeothermEx Inc. GeothermEx Inc. * * Power

  19. Global warming: Science or politics. Part 1

    SciTech Connect (OSTI)

    Dorweiler, V.P.

    1998-04-01

    ``The balance of evidence suggests that there has been a discernible influence of human activity on global climate`` is a statement employed as the foundation basis to intervene on behalf of the globe and the future. That statement, as scientific evidence of human-produced greenhouse gases (primarily CO{sub 2}) having a warming effect on global climate is a political statement only. Further, the Kyoto conference to consider intervention in human activities regarding global warming was a political conference. Political and treaty issues were the focus; scientific issues were not much discussed. What change is needed then to scientifically determine global warming and to ascertain whether human activity is involved? A better understanding of the natural climate variations related to solar variation can improve understanding of an anthropogenic greenhouse effect on the climate. The purpose of this article is to pose the scientific question. Part 2 will present an answer.

  20. Restoration of UA(1) symmetry and meson spectrum in hot or dense matter

    SciTech Connect (OSTI)

    Costa, P.; Ruivo, M.C.; Sousa, C.A. de; Kalinovsky, Yu.L.

    2005-06-14

    We explore the effects of breaking and restoration of chiral and axial symmetries using an extended three-flavor Nambu-Jona-Lasinio model that incorporates explicitly the axial anomaly through the 't Hooft interaction. We implement a temperature (density) dependence of the anomaly coefficient motivated by lattice results for the topological susceptibility. The spectrum of scalar and pseudoscalar mesons is analyzed bearing in mind the identification of chiral partners and the study of its convergence. We also concentrate on the behavior of the mixing angles that give us relevant information on the issue under discussion. The results suggest that the axial part of the symmetry is restored before the possible restoration of the full U(3)xU(3) chiral symmetry might occur.

  1. Quantifying properties of hot and dense QCD matter through systematic model-to-data comparison

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

    Bernhard, Jonah E.; Marcy, Peter W.; Coleman-Smith, Christopher E.; Huzurbazar, Snehalata; Wolpert, Robert L.; Bass, Steffen A.

    2015-05-22

    We systematically compare an event-by-event heavy-ion collision model to data from the CERN Large Hadron Collider. Using a general Bayesian method, we probe multiple model parameters including fundamental quark-gluon plasma properties such as the specific shear viscosity ?/s, calibrate the model to optimally reproduce experimental data, and extract quantitative constraints for all parameters simultaneously. Furthermore, the method is universal and easily extensible to other data and collision models.

  2. Quantifying properties of hot and dense QCD matter through systematic model-to-data comparison

    SciTech Connect (OSTI)

    Bernhard, Jonah E.; Marcy, Peter W.; Coleman-Smith, Christopher E.; Huzurbazar, Snehalata; Wolpert, Robert L.; Bass, Steffen A.

    2015-05-22

    We systematically compare an event-by-event heavy-ion collision model to data from the CERN Large Hadron Collider. Using a general Bayesian method, we probe multiple model parameters including fundamental quark-gluon plasma properties such as the specific shear viscosity η/s, calibrate the model to optimally reproduce experimental data, and extract quantitative constraints for all parameters simultaneously. Furthermore, the method is universal and easily extensible to other data and collision models.

  3. Carbonyl sulfide: No remedy for global warming

    SciTech Connect (OSTI)

    Taubman, S.J.; Kasting, J.F. [Pennsylvania State Univ., University Park, PA (United States)] [Pennsylvania State Univ., University Park, PA (United States)

    1995-04-01

    The authors look at the possibility of counteracting global warming forces by the injection of carbonyl sulfide (OCS) into the stratosphere at levels high enough to balance the impact say of a doubling of carbon dioxide concentrations, which are projected to result in a global 3{degrees} C warming. OCS injections at densities to provide such cooling will result a 30 percent impact of global ozone, whereas the carbon dioxide only made a 5% impact. In addition levels which would be found on the earths surface would be in the range 10 ppmv which is questionable as a safe exposure limit for humans, in addition to its impact on the ph of rainwater.

  4. SSAP Annual_13may2013.indb

    National Nuclear Security Administration (NNSA)

    ... Z-pinch Research on Radiation, Atomic and Plasma Physics Low Energy Nuclear Science 8 ... nonlinear optics of plasmas and laser-plasma interactions, and warm dense matter. ...

  5. Resolving Ultrafast Heating of Dense Cryogenic Hydrogen (Journal...

    Office of Scientific and Technical Information (OSTI)

    Dense Cryogenic Hydrogen Citation Details In-Document ... 1249390 Report Number(s): SLAC-REPRINT-2016-003 DOE Contract Number: AC02-76SF00515 Resource Type: Journal Article ...

  6. Reply to 'Comment on 'Quantum dense key distribution''

    SciTech Connect (OSTI)

    Degiovanni, I.P.; Berchera, I. Ruo; Castelletto, S.; Rastello, M.L.; Bovino, F.A.; Colla, A.M.; Castagnoli, G.

    2005-01-01

    In this Reply we propose a modified security proof of the quantum dense key distribution protocol, detecting also the eavesdropping attack proposed by Wojcik in his Comment [Wojcik, Phys. Rev. A 71, 016301 (2005)].

  7. DENSE MEDIUM CYCLONE OPTIMIZATON (Technical Report) | SciTech...

    Office of Scientific and Technical Information (OSTI)

    that cannot be upgraded in static dense medium separators, can be found in most modern coal plants and in a variety of mineral plants treating iron ore, dolomite, diamonds, potash...

  8. Nanoscale selective area growth of thick, dense, uniform, In...

    Office of Scientific and Technical Information (OSTI)

    Title: Nanoscale selective area growth of thick, dense, uniform, In-rich, InGaN nanostructure arrays on GaNsapphire template Authors: Sundaram, S. 1 ; Puybaret, R. 2 ; El ...

  9. SUPPORTED DENSE CERAMIC MEMBRANES FOR OXYGEN SEPARATION

    SciTech Connect (OSTI)

    Timothy L. Ward

    2002-07-01

    Mixed-conducting ceramics have the ability to conduct oxygen with perfect selectivity at elevated temperatures, making them extremely attractive as membrane materials for oxygen separation and membrane reactor applications. While the conductivity of these materials can be quite high at elevated temperatures (typically 800-1000 C), much higher oxygen fluxes, or, alternatively, equivalent fluxes at lower temperatures, could be provided by supported thin or thick film membrane layers. Based on that motivation, the objective of this project was to explore the use of ultrafine aerosol-derived powder of a mixed-conducting ceramic material for fabrication of supported thick-film dense membranes. The project focused on the mixed-conducting ceramic composition SrCo{sub 0.5}FeO{sub x} (SCFO) because of the desirable permeability and stability of that material, as reported in the literature. Appropriate conditions to produce the submicron SrCo{sub 0.5}FeO{sub x} powder using aerosol pyrolysis were determined. Porous supports of the same composition were produced by partial sintering of a commercially obtained powder that possessed significantly larger particle size than the aerosol-derived powder. The effects of sintering conditions (temperature, atmosphere) on the porosity and microstructure of the porous discs were studied, and a standard support fabrication procedure was adopted. Subsequently, a variety of paste and slurry formulations were explored utilizing the aerosol-derived SCFO powder. These formulations were applied to the porous SCFO support by a doctor blade or spin coating procedure. Sintering of the supported membrane layer was then conducted, and additional layers were deposited and sintered in some cases. The primary characterization methods were X-ray diffraction and scanning electron microscopy, and room-temperature nitrogen permeation was used to assess defect status of the membranes.We found that non-aqueous paste/slurry formulations incorporating

  10. Warm Hydroforming of Lightweight Metal Sheets

    SciTech Connect (OSTI)

    Aginagalde, A.; Orus, A.; Esnaola, J. A.; Torca, I.; Galdos, L.; Garcia, C.

    2007-05-17

    Hydroforming is well known in steel applications for automotive industry, where complicated shapes can be get with high strength to weight ratios. Nevertheless, the poor formability of light alloys at room temperature has limited the application of hydroforming technology for aluminum and magnesium parts. Increasing the temperature of these materials allows substantially greater elongation without fracture. Warm forming strategy is applied in conventional processes, such as rolling and forging, in order to get complex shapes, but still rare in hydroforming technology. This is the technical base of this research project: the development of the hydroforming process at warm working temperatures. The main tasks of the initial phases of the research were the material characterization, and the heated fluid and tooling system design and set up for warm hydroforming of lightweight alloys. Once these goals were accomplished the present paper shows the obtained results. The uniaxial tensile deformation of 5754H111, 6082-T6, 6082-O and AZ31B at the temperature range of 25 deg. C - 250 deg. C is presented as the output of the material characterization task. Both the system features and the results obtained for a bulge test geometry carried out with a warm hydroforming system are also presented. The selected alloys show an improvement in formability at the studied temperature range under both uniaxial and biaxial state of stress.

  11. Dark Matter Theory

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

    Dark Matter Theory Dark Matter Theory Understanding discoveries at the Energy, Intensity, and Cosmic Frontiers Get Expertise Rajan Gupta (505) 667-7664 Email Bruce Carlsten (505) ...

  12. Confederated Tribes of Warm Springs - Wind Energy Power Development

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

    Springs Power and Water Enterprise Use of DOE Grant DE-PS36-06GO96037 For Engineering Cost Assessment For Wind Energy Power Development On The Warm Springs Indian Reservation of Oregon. Prepared by: Warm Springs Power & Water Enterprises The Confederated Tribes of Warm Springs * Home of the Warm Springs, Wasco, and Paiute tribes, the Warm Springs Reservation is inhabited by nearly 4,500 tribal members, most of whom live in or around the town of Warm Springs. * Within the community, the

  13. Optimization of High-Volume Warm Forming for Lightweight Sheet...

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

    High-Volume Warm Forming for Lightweight Sheet Alloys Optimization of High-Volume Warm Forming for Lightweight Sheet Alloys 2012 DOE Hydrogen and Fuel Cells Program and Vehicle ...

  14. Confederated Tribes of the Warm Springs Reservation- 2002 Project

    Broader source: Energy.gov [DOE]

    Warm Springs Power Enterprises, a corporate entity owned and operated by the Confederated Tribes of Warm Springs, will conduct a 36-month comprehensive wind energy resource assessment and development feasibility study.

  15. Confederated Tribes of Warm Springs - Human Capacity Building

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

    Grant DE-PS36-06G096038 Human Capacity Building for Renewable Energy Development. Warm Spring Power and Water Enterprise Mark K. Johnson Jr. Prepared by: Warm Springs Power & Water ...

  16. Confederated Tribes of Warm Springs - Wind Feasibility Study

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

    Water Enterprises Wind Energy Development Feasibility Study Warm Springs Indian Reservation Oregon Confederated Tribes of Warm Springs Warm Springs, Oregon US Department of Energy Tribal Energy Program Review October 23-27 2006 Project Participants * Warm Springs Power & Water Enterprises * CTWS Dept. of Natural Resources * DW McClain and Associates: Project Management * OSU Energy Research Laboratory: Wind Modeling * Elcon Associates: Transmission System Studies * Northwest Wildlife

  17. Melting of ice wedges adds to arctic warming

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

    Can we someday predict earthquakes? Melting of ice wedges adds to arctic warming New ways of looking at seismic information and innovative laboratory experiments are offering tantalizing clues to what triggers earthquakes-and when. March 14, 2016 Ice throughout the Arctic is vanishing due to a rapidly warming climate. Ice throughout the Arctic is vanishing due to a rapidly warming climate. Melting of ice wedges adds to arctic warming Ice wedges are a particularly cool surface feature in the

  18. Latitudinal distribution of the recent Arctic warming

    SciTech Connect (OSTI)

    Chylek, Petr; Lesins, Glen K; Wang, Muyin

    2010-12-08

    Increasing Arctic temperature, disappearance of Arctic sea ice, melting of the Greenland ice sheet, sea level rise, increasing strength of Atlantic hurricanes are these impending climate catastrophes supported by observations? Are the recent data really unprecedented during the observational records? Our analysis of Arctic temperature records shows that the Arctic and temperatures in the 1930s and 1940s were almost as high as they are today. We argue that the current warming of the Arctic region is affected more by the multi-decadal climate variability than by an increasing concentration of carbon dioxide. Unfortunately, none of the existing coupled Atmosphere-Ocean General Circulation Models used in the IPCC 2007 cIimate change assessment is able to reproduce neither the observed 20th century Arctic cIimate variability nor the latitudinal distribution of the warming.

  19. A global warning for global warming

    SciTech Connect (OSTI)

    Paepe, R.

    1996-12-31

    The problem of global warming is a complex one not only because it is affecting desert areas such as the Sahel leading to famine disasters of poor rural societies, but because it is an even greater threat to modern well established industrial societies. Global warming is a complex problem of geographical, economical and societal factors together which definitely are biased by local environmental parameters. There is an absolute need to increase the knowledge of such parameters, especially to understand their limits of variance. The greenhouse effect is a global mechanism which means that in changing conditions at one point of the Earth, it will affect all other regions of the globe. Industrial pollution and devastation of the forest are quoted as similar polluting anthropogenic activities in far apart regions of the world with totally different societies and industrial compounds. The other important factor is climatic cyclicity which means that droughts are bound to natural cycles. These natural cycles are numerous as is reflected in the study of geo-proxydata from several sequential geological series on land, ice and deepsea. Each of these cycles reveals a drought cycle which occasionally interfere at the same time. It is believed that the present drought might well be a point of interference between the natural cycles of 2,500 and 1,000 years and the man induced cycle of the last century`s warming up. If the latter is the only cycle involved, man will be able to remediate. If not, global warming will become even more disastrous beyond the 21st century.

  20. Computer modeling of the global warming effect

    SciTech Connect (OSTI)

    Washington, W.M.

    1993-12-31

    The state of knowledge of global warming will be presented and two aspects examined: observational evidence and a review of the state of computer modeling of climate change due to anthropogenic increases in greenhouse gases. Observational evidence, indeed, shows global warming, but it is difficult to prove that the changes are unequivocally due to the greenhouse-gas effect. Although observational measurements of global warming are subject to ``correction,`` researchers are showing consistent patterns in their interpretation of the data. Since the 1960s, climate scientists have been making their computer models of the climate system more realistic. Models started as atmospheric models and, through the addition of oceans, surface hydrology, and sea-ice components, they then became climate-system models. Because of computer limitations and the limited understanding of the degree of interaction of the various components, present models require substantial simplification. Nevertheless, in their present state of development climate models can reproduce most of the observed large-scale features of the real system, such as wind, temperature, precipitation, ocean current, and sea-ice distribution. The use of supercomputers to advance the spatial resolution and realism of earth-system models will also be discussed.

  1. Weatherization Installer/Technician Fundamentals 2.0 - Dense Pack Sidewall

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

    Insulation | Department of Energy Dense Pack Sidewall Insulation Weatherization Installer/Technician Fundamentals 2.0 - Dense Pack Sidewall Insulation Dense Pack Sidewall Insulation - Complete (10.56 MB) Lesson Plan: Dense Pack Sidewall Insulation (126.47 KB) PowerPoint: Dense Pack Sidewall Insulation (10.92 MB) More Documents & Publications Energy Auditor - Single Family 2.0: Building Shell Retrofit Strategies Weatherization Installer/Technician Fundamentals 2.0 - Identifying and Air

  2. Quasimolecules and spectral line broadening in dense plasmas

    SciTech Connect (OSTI)

    Arranz, J. P.; Butaux, J.; Nguyen, H.; Reggadi, A.

    1997-01-05

    The energy levels and transition probabilities for transient diatomic molecules have been obtained by means of a self-consistent field method and used to compute the static and dynamical NeX Lyman {alpha} and Lyman {beta} line profiles emitted from dense plasmas. The typical excitation of molecular satellite lines is pointed out.

  3. Global warming: Science or politics? Part 2

    SciTech Connect (OSTI)

    Dorweiler, V.P.

    1998-05-01

    Supplementing the conclusion that ``there has been a discernible influence of human activity on global climate`` is a set of dire consequences to the globe and human population. One consequence is the spread of tropical diseases. It has not been concluded whether the spread of disease is due to global conditions or to opening of tropical forests to commerce, allowing spread by travelers. Whether these forecasts abet the claimed relation of human activity to global warming, they are not a new phenomenon. In the space of several decades, dire consequences have been forecast in three sectors: natural resource consumption, energy resources and environmental fate. These three areas are reviewed.

  4. Asymmetric dark matter

    SciTech Connect (OSTI)

    Kumar, Jason

    2014-06-24

    We review the theoretical framework underlying models of asymmetric dark matter, describe astrophysical constraints which arise from observations of neutron stars, and discuss the prospects for detecting asymmetric dark matter.

  5. The Hubble Web: The Dark Matter Problem and Cosmic Strings

    SciTech Connect (OSTI)

    Alexander, Stephon

    2009-07-06

    I propose a reinterpretation of cosmic dark matter in which a rigid network of cosmic strings formed at the end of inflation. The cosmic strings fulfill three functions: At recombination they provide an accretion mechanism for virializing baryonic and warm dark matter into disks. These cosmic strings survive as configurations which thread spiral and elliptical galaxies leading to the observed flatness of rotation curves and the Tully-Fisher relation. We find a relationship between the rotational velocity of the galaxy and the string tension and discuss the testability of this model.

  6. Particulate Matter Aerosols

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

    particulate matter aerosols Particulate Matter Aerosols The study of atmospheric aerosols is important because of its adverse effects on health, air quality, visibility, cultural heritage, and Earth's radiation balance. Techniques that can help better characterize particulate matter are required to better understand the constituents, causes and sources of particulate matter (PM) aerosols. Carbon is one of the main constituents of atmospheric aerosols. Radiocarbon (14C) measurement performed on

  7. Black carbon contribution to global warming

    SciTech Connect (OSTI)

    Chylek, P.; Johnson, B.; Kou, L.; Wong, J.

    1996-12-31

    Before the onset of industrial revolution the only important source of black carbon in the atmosphere was biomass burning. Today, black carbon production is divided between the biomass and fossil fuel burning. Black carbon is a major agent responsible for absorption of solar radiation by atmospheric aerosols. Thus black carbon makes other aerosols less efficient in their role of reflecting solar radiation and cooling the earth-atmosphere system. Black carbon also contributes to the absorption of solar radiation by clouds and snow cover. The authors present the results of black carbon concentrations measurements in the atmosphere, in cloud water, in rain and snow melt water collected during the 1992--1996 time period over the southern Nova Scotia. Their results are put into the global and historical perspective by comparing them with the compilation of past measurements at diverse locations and with their measurements of black carbon concentrations in the Greenland and Antarctic ice cores. Black carbon contribution to the global warming is estimated, and compared to the carbon dioxide warming, using the radiative forcing caused by the black carbon at the top of the atmosphere.

  8. {sup 85}Kr induced global warming

    SciTech Connect (OSTI)

    Zakharov, V.I.

    1996-12-31

    It`s well known that the trace atmospheric constituent as {sup 85}Kr is at present about 10{sup 6} cm{sup {minus}3} and increasing considerably (twice every 8--10 years) as a result of nuclear fuel utilization. This paper presents the model of influence of {sup 85}Kr accumulation in the earth atmosphere on climate perturbation and global warming. The process of increasing the concentrations in the troposphere due to the anthropogenic emission of {sup 85}Kr and its radioactive decay is analyzed, based on master kinetic equations. Results indicate that anthropogenic emissions contributing to the total equilibrium concentration of tropospheric ions due to {sup 85}Kr is about equal to the natural level of tropospheric ions. The influence of atmospheric electricity on the transformation between water vapor and clouds which result in an increase in the concentration of ions in troposphere is investigated. The paper shows that the process of anthropogenic accumulation of {sup 85}Kr in the troposphere at present rate up to 2005--2010 increases the mean of the dew-point temperature several degrees on the global scale. Relevant change of height for the lower level of clouds has been obtained. Positive feedback between the process of warming of the lower atmosphere and the concentration of tropospheric ions has been considered.

  9. A warm air poultry brooding system

    SciTech Connect (OSTI)

    Nulte, W.H.

    1980-12-01

    As the energy crisis escalated during the mid-70's, it became apparent that energy intensive industries must seek alternate fuel sources. Georgia Tech realized that one of these industries was the poultry industry. Consequently, a demonstration project of a wood-fired, warm air poultry brooding system was designed and built. Since its completion in mid-1978, the system has demonstrated considerable cost savings as well as being a very functional and reliable system. The system consists of 3 main components--a wood burning furnace, a supply distribution and return duct, and 20 flexible ducts which simulate the function of the propane brooders by providing warm air close to the ground. A separate structure houses the furnace and wood supply. This house is located at the midpoint of the growout house to allow symmetrical and naturally balanced air distribution. Since the system became operational, 16 flocks of birds have been brooded. During this time, wood usage has averaged approximately 30 cords per year while in a neighboring house, that is used as a control house, the propane usage has averaged 3,800 gallons per year. In the area of Georgia where the demonstration project is located, the cost of fuelwood has remained stable over the last 2 years, whereas the price of propane has continually increased. Thus the grower has the benefit of constantly increasing cost savings while utilizing a renewable resource as fuel.

  10. Big Questions: Dark Matter

    ScienceCinema (OSTI)

    Lincoln, Don

    2014-08-07

    Carl Sagan's oft-quoted statement that there are "billions and billions" of stars in the cosmos gives an idea of just how much "stuff" is in the universe. However scientists now think that in addition to the type of matter with which we are familiar, there is another kind of matter out there. This new kind of matter is called "dark matter" and there seems to be five times as much as ordinary matter. Dark matter interacts only with gravity, thus light simply zips right by it. Scientists are searching through their data, trying to prove that the dark matter idea is real. Fermilab's Dr. Don Lincoln tells us why we think this seemingly-crazy idea might not be so crazy after all.

  11. Big Questions: Dark Matter

    SciTech Connect (OSTI)

    Lincoln, Don

    2013-12-05

    Carl Sagan's oft-quoted statement that there are "billions and billions" of stars in the cosmos gives an idea of just how much "stuff" is in the universe. However scientists now think that in addition to the type of matter with which we are familiar, there is another kind of matter out there. This new kind of matter is called "dark matter" and there seems to be five times as much as ordinary matter. Dark matter interacts only with gravity, thus light simply zips right by it. Scientists are searching through their data, trying to prove that the dark matter idea is real. Fermilab's Dr. Don Lincoln tells us why we think this seemingly-crazy idea might not be so crazy after all.

  12. Thermodynamic Evaluation of Low-Global Warming Potential Refrigerants -

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

    2013 Peer Review | Department of Energy Thermodynamic Evaluation of Low-Global Warming Potential Refrigerants - 2013 Peer Review Thermodynamic Evaluation of Low-Global Warming Potential Refrigerants - 2013 Peer Review Emerging Technologies Project for the 2013 Building Technologies Office's Program Peer Review emrgtech13_mclinden_040213.pdf (2.18 MB) More Documents & Publications Credit: National Institute of Standards Thermodynamic Evaluation of Low-Global Warming Potential Refrigerants

  13. Picture of the Week: Climate feedbacks from a warming arctic

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

    8 Climate feedbacks from a warming arctic Los Alamos National Laboratory scientists work to understand the fate of this carbon using computer simulations such as this model of snowmelt draining from polygonal ground near Barrow, Alaska. April 26, 2015 Climate feedbacks from a warming arctic x Arctic soils currently store nearly 20 years worth of human emissions of carbon in frozen permafrost, but the Arctic is warming faster than most of the rest of the Earth, meaning that this carbon may soon

  14. Wildfires may contribute more to global warming than previously predicted

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

    Wildfires may contribute more to global warming Wildfires may contribute more to global warming than previously predicted They suggest that fire emissions could contribute a lot more to the observed climate warming than current estimates show. July 9, 2013 Haze of smoke emanating from the 2011 Las Conchas, NM fire. Haze of smoke emanating from the 2011 Las Conchas, NM fire. Contact Nancy Ambrosiano Communications Office (505) 667-0471 Email "The fact that we are experiencing more fires and

  15. Confederated Tribes of Warm Springs - Geothermal Feasibility Study

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

    Springs The Confederated Tribes Of Warm Springs Presentation to DOE Department of Renewable Energy Presentation to DOE Department of Renewable Energy October, 2005 for Geothermal Development Potential on Confederated Tribes of Warm Springs Reservation of Oregon repared by: Warm Springs Power Enterprises History with Energy Developments History with Energy Developments * * Intro to Power business in 1955 with the development of the Pelt Intro to Power business in 1955 with the development of the

  16. Confederated Tribes of Warm Springs - Geothermal Feasibility Study

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

    Springs Presentation to DOE Department of Renewable Energy October , 2007 For Geothermal Development Potential On Confederated Tribes of Warm Springs Reservation of Oregon Lands Prepared by: Warm Springs Power & Water Enterprises History With Energy Developments Intro to Power business in 1955 with the development of the Pelton Project. 1970 with the installation of three 3 MW steam turbines at Warm Springs Forest Products Industries (WSFPI). 1982 completed the installation of the Pelton

  17. ARM - Possible Benefits of Global Warming on Agriculture

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

    ListPossible Benefits of Global Warming on Agriculture Outreach Home Room News Publications Traditional Knowledge Kiosks Barrow, Alaska Tropical Western Pacific Site Tours Contacts Students Study Hall About ARM Global Warming FAQ Just for Fun Meet our Friends Cool Sites Teachers Teachers' Toolbox Lesson Plans Possible Benefits of Global Warming on Agriculture Pros and Cons Given the need for caution, it may still be possible to make a few general comments. With more carbon dioxide in the

  18. ARM - What Are the Effects of Global Warming?

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

    Are the Effects of Global Warming? Outreach Home Room News Publications Traditional Knowledge Kiosks Barrow, Alaska Tropical Western Pacific Site Tours Contacts Students Study Hall About ARM Global Warming FAQ Just for Fun Meet our Friends Cool Sites Teachers Teachers' Toolbox Lesson Plans What Are the Effects of Global Warming? Changes in Crop and Plant Life In the mid-latitudes (this includes most of the United States), the amount of moisture in the soil will probably decrease in the summer.

  19. ARM - What Are the Effects of Global Warming?

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

    Outreach Home Room News Publications Traditional Knowledge Kiosks Barrow, Alaska Tropical Western Pacific Site Tours Contacts Students Study Hall About ARM Global Warming FAQ Just for Fun Meet our Friends Cool Sites Teachers Teachers' Toolbox Lesson Plans What Are the Effects of Global Warming? As greenhouse gases continue to increase, the earth may experience significant climate changes. In addition, there are many other impacts that global warming can have on the earth. You can learn more

  20. ARM - What Will Happen as a Result of Global Warming?

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

    What Will Happen as a Result of Global Warming? Outreach Home Room News Publications Traditional Knowledge Kiosks Barrow, Alaska Tropical Western Pacific Site Tours Contacts Students Study Hall About ARM Global Warming FAQ Just for Fun Meet our Friends Cool Sites Teachers Teachers' Toolbox Lesson Plans What Will Happen as a Result of Global Warming? Major Stratospheric Cooling Virtually certain. Because there is erosion of upper stratospheric ozone by chlorofluorocarbons (CFCs), there is less

  1. 100 LPW 800 Lm Warm White LED

    SciTech Connect (OSTI)

    Sun, Decai

    2010-10-31

    An illumination grade warm white (WW) LED, having correlated color temperature (CCT) between 2800 K and 3500K and capable of producing 800 lm output at 100 lm/W, has been developed in this program. The high power WW LED is an ideal source for use as replacement for incandescent, and Halogen reflector and general purpose lamps of similar lumen value. Over the two year period, we have made following accomplishments: developed a high power warm white LED product and made over 50% improvements in light output and efficacy. The new high power WW LED product is a die on ceramic surface mountable LED package. It has four 1x1 mm{sup 2} InGaN pump dice flip chip attached to a ceramic submount in 2x2 array, covered by warm white phosphor ceramic platelets called Lumiramica and an overmolded silicone lens encapsulating the LED array. The performance goal was achieved through breakthroughs in following key areas: (1) High efficiency pump LED development through pump LED active region design and epi growth quality improvement (funded by internal programs). (2) Increase in injection efficiency (IE) represented by reduction in forward voltage (V{sub f}) through the improvement of the silver-based p-contact and a reduction in spreading resistance. The injection efficiency was increased from 80% at the start of the program to 96% at the end of the program at 700 mA/mm{sup 2}. (3) Improvement in thermal design as represented by reduction in thermal resistance from junction to case, through improvement of the die to submount connection in the thin film flip chip (TFFC) LED and choosing the submount material of high thermal conductivity. A thermal resistance of 1.72 K/W was demonstrated for the high power LED package. (4) Improvement in extraction efficiency from the LED package through improvement of InGaN die level and package level optical extraction efficiency improvement. (5) Improvement in phosphor system efficiency by improving the lumen equivalent (LE) and phosphor package

  2. Roosevelt Warm Springs Institute for Rehab. Pool & Spa Low Temperature...

    Open Energy Info (EERE)

    Low Temperature Geothermal Facility Jump to: navigation, search Name Roosevelt Warm Springs Institute for Rehab. Pool & Spa Low Temperature Geothermal Facility Facility...

  3. Theory of factors limiting high gradient operation of warm acceleratin...

    Office of Scientific and Technical Information (OSTI)

    Theory of factors limiting high gradient operation of warm accelerating structures Citation Details In-Document Search Title: Theory of factors limiting high gradient operation of ...

  4. Warm Springs State Hospital Space Heating Low Temperature Geothermal...

    Open Energy Info (EERE)

    State Hospital Space Heating Low Temperature Geothermal Facility Jump to: navigation, search Name Warm Springs State Hospital Space Heating Low Temperature Geothermal Facility...

  5. Roosevelt Warm Springs Institute for Rehab. Space Heating Low...

    Open Energy Info (EERE)

    Space Heating Low Temperature Geothermal Facility Jump to: navigation, search Name Roosevelt Warm Springs Institute for Rehab. Space Heating Low Temperature Geothermal Facility...

  6. Call for emission limits heats debate on global warming

    SciTech Connect (OSTI)

    Singer, S.F.

    1997-08-01

    Emission limits on carbon dioxide is recommended by an Intergovernmental Panel in a discussion on global warming. (AIP) {copyright} {ital 1997 American Institute of Physics.}

  7. The Tropical Warm Pool International Cloud Experiment: Overview

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

    The Tropical Warm Pool International Cloud Experiment: Overview May, Peter Bureau or Meteorology Research Centre Mather, James Pacific Northwest National Laboratory Jakob,...

  8. Thermodynamic Evaluation of Low-Global Warming Potential Refrigerants...

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

    Warming Potential Refrigerants Mechanical Solutions, Inc.'s ultra-small centrifugal compressor concept will facilitate low-GWP refrigerant adoption.
    Photo Credit: Mechanical ...

  9. Water trees to beat drought and global warming

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

    Water trees to beat drought and global warming Community Connections: Your link to news and opportunities from Los Alamos National Laboratory Latest Issue: September 1, 2016 all issues All Issues » submit Water trees to beat drought and global warming Large trees are at risk in Northern New Mexico. May 2, 2016 Drought combined with global warming is a major threat to our trees in Northern New Mexico-and around the world-says LANL ecologist Nate McDowell. Drought combined with global warming is

  10. Warm Springs Water District District Heating Low Temperature...

    Open Energy Info (EERE)

    Water District District Heating Low Temperature Geothermal Facility Jump to: navigation, search Name Warm Springs Water District District Heating Low Temperature Geothermal...

  11. Research & Development Roadmap: Next-Generation Low Global Warming...

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

    Low Global Warming Potential Refrigerants Research & Development Roadmap: Next-Generation ... This research and development (R&D) roadmap for next-generation low-GWP refrigerants ...

  12. Water trees to beat drought and global warming

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

    Water trees to beat drought and global warming Community Connections: Your link to news ... Latest Issue: September 1, 2016 all issues All Issues submit Water trees to beat ...

  13. COMPARING DENSE GALAXY CLUSTER REDSHIFT SURVEYS WITH WEAK-LENSING MAPS

    SciTech Connect (OSTI)

    Hwang, Ho Seong; Geller, Margaret J.; Zahid, H. Jabran; Diaferio, Antonaldo; Rines, Kenneth J. E-mail: mgeller@cfa.harvard.edu E-mail: diaferio@ph.unito.it

    2014-12-20

    We use dense redshift surveys of nine galaxy clusters at z ∼ 0.2 to compare the galaxy distribution in each system with the projected matter distribution from weak lensing. By combining 2087 new MMT/Hectospec redshifts and the data in the literature, we construct spectroscopic samples within the region of weak-lensing maps of high (70%-89%) and uniform completeness. With these dense redshift surveys, we construct galaxy number density maps using several galaxy subsamples. The shape of the main cluster concentration in the weak-lensing maps is similar to the global morphology of the number density maps based on cluster members alone, mainly dominated by red members. We cross-correlate the galaxy number density maps with the weak-lensing maps. The cross-correlation signal when we include foreground and background galaxies at 0.5z {sub cl} < z < 2z {sub cl} is 10%-23% larger than for cluster members alone at the cluster virial radius. The excess can be as high as 30% depending on the cluster. Cross-correlating the galaxy number density and weak-lensing maps suggests that superimposed structures close to the cluster in redshift space contribute more significantly to the excess cross-correlation signal than unrelated large-scale structure along the line of sight. Interestingly, the weak-lensing mass profiles are not well constrained for the clusters with the largest cross-correlation signal excesses (>20% for A383, A689, and A750). The fractional excess in the cross-correlation signal including foreground and background structures could be a useful proxy for assessing the reliability of weak-lensing cluster mass estimates.

  14. 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.

  15. Ultra-Efficient and Power-Dense Electric Motors

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

    Ultra-Efficient and Power-Dense Electric Motors Advanced Electric Motors Offer Large Energy Savings in Industrial Applications Pumps, fans, and compressors use more than 60% of industrial electric motor energy in the United States. The most widely used motors in these applications are constant-speed motors that are started and run across the line. In some applications, variable- speed motors, powered from an open-loop variable-speed drive, are utilized without any rotor position feedback device

  16. Method for making dense crack free thin films

    DOE Patents [OSTI]

    Jacobson, Craig P.; Visco, Steven J.; De Jonghe, Lutgard C.

    2007-01-16

    The process described herein provides a simple and cost effective method for making crack free, high density thin ceramic film. The steps involve depositing a layer of a ceramic material on a porous or dense substrate. The deposited layer is compacted and then the resultant laminate is sintered to achieve a higher density than would have been possible without the pre-firing compaction step.

  17. Compacting Plastic-Bonded Explosive Molding Powders to Dense Solids

    SciTech Connect (OSTI)

    B. Olinger

    2005-04-15

    Dense solid high explosives are made by compacting plastic-bonded explosive molding powders with high pressures and temperatures for extended periods of time. The density is influenced by manufacturing processes of the powders, compaction temperature, the magnitude of compaction pressure, pressure duration, and number of repeated applications of pressure. The internal density variation of compacted explosives depends on method of compaction and the material being compacted.

  18. Global warming, global research, and global governing

    SciTech Connect (OSTI)

    Preining, O.

    1997-12-31

    The anticipated dangers of Global Warming can be mitigated by reducing atmospheric greenhouse gas concentrations, especially CO{sub 2}. To reach acceptable, constant levels within the next couple of centuries it might be necessary to accept stabilization levels higher than present ones, The annual CO{sub 2} emissions must be reduced far below today`s values. This is a very important result of the models discussed in the 1995 IPCC report. However, any even very modest scenario for the future must take into account a substantial increase in the world population which might double during the 21st century, There is a considerable emission reduction potential of the industrialized world due to efficiency increase, However, the demand for energy services by the growing world population will, inspite of the availability of alternative energy resources, possibly lead to a net increase in fossil fuel consumption. If the climate models are right, and the science community believes they are, we will experience a global warming of the order of a couple of degrees over the next century; we have to live with it. To be prepared for the future it is essential for us to use new research techniques embracing not only the familiar fields of hard sciences but also social, educational, ethical and economic aspects, We must find a way to build up the essential intellectual capacities needed to deal with these kinds of general problems within all nations and all societies. But this is not Although, we also have to find the necessary dynamical and highly flexible structures for a global governing using tools such as the environmental regime. The first step was the Framework Convention On Climate Change, UN 1992; for resolution of questions regarding implementations the Conference of the Parties was established.

  19. PROTON-CONDUCTING DENSE CERAMIC MEMBRANES FOR HYDROGEN SEPARATION

    SciTech Connect (OSTI)

    Jerry Y. S. Lin; Scott Cheng; Vineet Gupta

    2003-12-01

    Dense perovskite-type structured ceramic membranes, SrCe{sub 0.95}Tm{sub 0.05}O{sub 3} (SCTm), of different thickness, were prepared by the dry-press method. Membrane thickness was varied from 3 mm to 150 {micro}m. The hydrogen permeation flux was found to be inversely proportional to the thickness of the dense films, indicating that the bulk diffusion rather than the surface reaction played a dominant role in the H{sub 2} transport through these dense membranes within the studied thickness range. Hydrogen permeation flux increases with increasing upstream hydrogen partial pressure and decreasing downstream hydrogen partial pressure. The activation energy for hydrogen permeation through the SCTm membrane is about 116 kJ/mol in 600-700 C and 16 kJ/mol in 750-950 C. This indicates a change in the electrical and protonic conduction mechanism at around 700 C. Pd-Cu thin films were synthesized with elemental palladium and copper targets by the sequential R.F. sputter deposition on porous substrates. Pd-Cu alloy films could be formed after proper annealing. The deposited Pd-Cu films were gas-tight. This result demonstrated the feasibility of obtaining an ultrathin SCTm film by the sequential sputter deposition of Sr, Ce and Tm metals followed by proper annealing and oxidation. Such ultrathin SCTm membranes will offer sufficiently high hydrogen permeance for practical applications.

  20. Enhanced Productivity of Chemical Processes Using Dense Fluidized Beds

    SciTech Connect (OSTI)

    Sibashis Banerjee; Alvin Chen; Rutton Patel; Dale Snider; Ken Williams; Timothy O'Hern; Paul Tortora

    2008-02-29

    The work detailed in this report addresses Enabling Technologies within Computational Technology by integrating a breakthrough particle-fluid computational technology into traditional Process Science and Engineering Technology. The work completed under this DOE project addresses five major development areas 1) gas chemistry in dense fluidized beds 2) thermal cracking of liquid film on solids producing gas products 3) liquid injection in a fluidized bed with particle-to-particle liquid film transport 4) solid-gas chemistry and 5) first level validation of models. Because of the nature of the research using tightly coupled solids and fluid phases with a Lagrangian description of the solids and continuum description of fluid, the work provides ground-breaking advances in reactor prediction capability. This capability has been tested against experimental data where available. The commercial product arising out of this work is called Barracuda and is suitable for a wide (dense-to-dilute) range of industrial scale gas-solid flows with and without reactions. Commercial applications include dense gas-solid beds, gasifiers, riser reactors and cyclones.

  1. PROTON-CONDUCTING DENSE CERAMIC MEMBRANES FOR HYDROGEN SEPARATION

    SciTech Connect (OSTI)

    Jerry Y.S. Lin; Vineet Gupta; Scott Cheng

    2004-11-01

    Dense thin films of SrCe{sub 0.95}Tm{sub 0.05}O{sub 3-{delta}} (SCTm) with perovskite structure were prepared on porous alumina or SCTm substrates by the methods of (1) polymeric-gel casting and (2) dry-pressing. The polymeric-gel casting method includes preparation of mixed metal oxide gel and coating of the gel on a macroporous alumina support. Micrometer thick SCTm films of the perovskite structure can be obtained by the polymeric-gel casting method. However, the deposited films are not hermetic and it may require about 50 coatings in order to obtain gas-tight SCTm films by this method. Pd-Cu thin films were synthesized with elemental palladium and copper targets by the sequential R.F. sputter deposition on porous substrates. Pd-Cu alloy films could be formed after proper annealing. The deposited Pd-Cu films were gas-tight. This result demonstrated the feasibility of obtaining an ultrathin SCTm film by the sequential sputter deposition of Sr, Ce and Tm metals followed by proper annealing and oxidation. Such ultrathin SCTm membranes will offer sufficiently high hydrogen permeance for practical applications. Thin gas-tight SCTm membranes were synthesized on porous SCTm supports by the dry-pressing method. In this method, the green powder of SCTm was prepared by wet chemical method using metal nitrates as the precursors. Particle size of the powder was revealed to be a vital factor in determining the porosity and shrinkage of the sintered disks. Small particle size formed the dense film while large particle size produced porous substrates. The SCTm film thickness was varied from 1 mm to 0.15 mm by varying the amount of the target powder. A close match between the shrinkage of the substrate and the dense film led to the defect free-thin films. The selectivity of H{sub 2} over He with these films was infinite. The chemical environment on each side of the membrane influenced the H{sub 2} permeation flux as it had concurrent effects on the driving force and electronic

  2. Fully Kinetic Simulations of MegaJoule-Scale Dense Plasma Focus...

    Office of Scientific and Technical Information (OSTI)

    Journal Article: Fully Kinetic Simulations of MegaJoule-Scale Dense Plasma Focus Citation Details In-Document Search Title: Fully Kinetic Simulations of MegaJoule-Scale Dense ...

  3. Ghost dark matter

    SciTech Connect (OSTI)

    Furukawa, Tomonori; Yokoyama, Shuichiro; Ichiki, Kiyotomo; Sugiyama, Naoshi; Mukohyama, Shinji E-mail: shu@a.phys.nagoya-u.ac.jp E-mail: naoshi@a.phys.nagoya-u.ac.jp

    2010-05-01

    We revisit ghost dark matter, the possibility that ghost condensation may serve as an alternative to dark matter. In particular, we investigate the Friedmann-Robertson-Walker (FRW) background evolution and the large-scale structure (LSS) in the ΛGDM universe, i.e. a late-time universe dominated by a cosmological constant and ghost dark matter. The FRW background of the ΛGDM universe is indistinguishable from that of the standard ΛCDM universe if M∼>1eV, where M is the scale of spontaneous Lorentz breaking. From the LSS we find a stronger bound: M∼>10eV. For smaller M, ghost dark matter would have non-negligible sound speed after the matter-radiation equality, and thus the matter power spectrum would significantly differ from observation. These bounds are compatible with the phenomenological upper bound M∼<100GeV known in the literature.

  4. Neutrinos and dark matter

    SciTech Connect (OSTI)

    Ibarra, Alejandro

    2015-07-15

    Neutrinos could be key particles to unravel the nature of the dark matter of the Universe. On the one hand, sterile neutrinos in minimal extensions of the Standard Model are excellent dark matter candidates, producing potentially observable signals in the form of a line in the X-ray sky. On the other hand, the annihilation or the decay of dark matter particles produces, in many plausible dark matter scenarios, a neutrino flux that could be detected at neutrino telescopes, thus providing non-gravitational evidence for dark matter. More conservatively, the non-observation of a significant excess in the neutrino fluxes with respect to the expected astrophysical backgrounds can be used to constrain dark matter properties, such as the self-annihilation cross section, the scattering cross section with nucleons and the lifetime.

  5. Materials/Condensed Matter

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

    Materials/Condensed Matter Materials/Condensed Matter Print Materials research provides the foundation on which the economic well being of our high-tech society rests. The impact of advanced materials ranges dramatically over every aspect of our modern world from the minutiae of daily life to the grand scale of our national economy. Invariably, however, breakthroughs to new technologies trace their origin both to fundamental research in the basic properties of condensed matter and to applied

  6. Dark Matter Theory

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

    Dark Matter Theory Dark Matter Theory Understanding discoveries at the Energy, Intensity, and Cosmic Frontiers Get Expertise Rajan Gupta (505) 667-7664 Email Bruce Carlsten (505) 667-5657 Email Dark Matter Theory The existence of dark matter can be traced back to the pioneering discoveries of Fritz Zwicky and Jan Oort that the motion of galaxies in the Coma cluster, and of nearby stars in our own Galaxy, do not follow the expected motion based on Newton's law of gravity and the observed visible

  7. Cosmology with Mimetic Matter

    SciTech Connect (OSTI)

    Chamseddine, Ali H.; Mukhanov, Viatcheslav; Vikman, Alexander E-mail: viatcheslav.Mukhanov@lmu.de

    2014-06-01

    We consider minimal extensions of the recently proposed Mimetic Dark Matter and show that by introducing a potential for the mimetic non-dynamical scalar field we can mimic nearly any gravitational properties of the normal matter. In particular, the mimetic matter can provide us with inflaton, quintessence and even can lead to a bouncing nonsingular universe. We also investigate the behaviour of cosmological perturbations due to a mimetic matter. We demonstrate that simple mimetic inflation can produce red-tilted scalar perturbations which are largely enhanced over gravity waves.

  8. Science on Tap - Matter

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

    Science on Tap - Matter Science on Tap - Matter WHEN: Feb 18, 2016 5:30 PM - 7:00 PM WHERE: UnQuarked Wine Room 145 Central Park Square, Los Alamos, New Mexico 87544 USA SPEAKER: Jack Shlachter CONTACT: Linda Anderman (505) 665-9196 CATEGORY: Bradbury INTERNAL: Calendar Login Event Description Mark your calendars for this event held every third Thursday from 5:30 to 7 p.m. A short presentation is followed by a lively discussion on a different subject each month. What's the Matter with Matter?

  9. Energy Matters Mailbag

    Broader source: Energy.gov [DOE]

    This edition of the mailbag tackles follow-up questions from our Energy Matters discussion on breaking our reliance on foreign oil.

  10. Magnetization of neutron matter

    SciTech Connect (OSTI)

    Bigdeli, M.

    2011-09-21

    In this paper, we compute magnetization of neutron matter at strong magnetic field using the lowest order constrained variational (LOCV) technique.

  11. 1991 US-Japan workshop on Nuclear Fusion in Dense Plasmas. Proceedings

    SciTech Connect (OSTI)

    Ichimaru, S.; Tajima, T.

    1991-10-01

    The scientific areas covered at the Workshop may be classified into the following subfields: (1) basic theory of dense plasma physics and its interface with atomic physics and nuclear physics; (2) physics of dense z-pinches, ICF plasmas etc; (3) stellar interior plasmas; (4) cold fusion; and (5) other dense plasmas.

  12. Time-Resolved

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

    Ultrafast Spectroscopy of Warm Dense Matter Real-Time Chemical Imaging of Bacterial Biofilm Development Using Light to Control How X Rays Interact with Matter X-Ray Imaging of...

  13. The Tropical Warm Pool International Cloud Experiment

    SciTech Connect (OSTI)

    May, Peter T.; Mather, James H.; Vaughan, Geraint; Jakob, Christian; McFarquhar, Greg; Bower, Keith; Mace, Gerald G.

    2008-05-01

    One of the most complete data sets describing tropical convection ever collected will result from the upcoming Tropical Warm Pool International Cloud Experiment (TWP-ICE) in the area around Darwin, Northern Australia in January and February 2006. The aims of the experiment, which will be operated in conjunction with the DOE Atmospheric Radiation Measurement (ARM) site in Darwin, will be to examine convective cloud systems from their initial stages through to the decay of the cirrus generated and to measure their impact on the environment. The experiment will include an unprecedented network of ground-based observations (soundings, active and passive remote sensors) combined with low, mid and high altitude aircraft for in-situ and remote sensing measurements. A crucial outcome of the experiment will be a data set suitable to provide the forcing and evaluation data required by cloud resolving and single column models as well as global climate models (GCMs) with the aim to contribute to parameterization development. This data set will provide the necessary link between the observed cloud properties and the models that are attempting to simulate them. The experiment is a large multi-agency experiment including substantial contributions from the United States DOE ARM program, ARM-UAV program, NASA, the Australian Bureau of Meteorology, CSIRO, EU programs and many universities.

  14. Parallel Access of Out-Of-Core Dense Extendible Arrays

    SciTech Connect (OSTI)

    Otoo, Ekow J; Rotem, Doron

    2007-07-26

    Datasets used in scientific and engineering applications are often modeled as dense multi-dimensional arrays. For very large datasets, the corresponding array models are typically stored out-of-core as array files. The array elements are mapped onto linear consecutive locations that correspond to the linear ordering of the multi-dimensional indices. Two conventional mappings used are the row-major order and the column-major order of multi-dimensional arrays. Such conventional mappings of dense array files highly limit the performance of applications and the extendibility of the dataset. Firstly, an array file that is organized in say row-major order causes applications that subsequently access the data in column-major order, to have abysmal performance. Secondly, any subsequent expansion of the array file is limited to only one dimension. Expansions of such out-of-core conventional arrays along arbitrary dimensions, require storage reorganization that can be very expensive. Wepresent a solution for storing out-of-core dense extendible arrays that resolve the two limitations. The method uses a mapping function F*(), together with information maintained in axial vectors, to compute the linear address of an extendible array element when passed its k-dimensional index. We also give the inverse function, F-1*() for deriving the k-dimensional index when given the linear address. We show how the mapping function, in combination with MPI-IO and a parallel file system, allows for the growth of the extendible array without reorganization and no significant performance degradation of applications accessing elements in any desired order. We give methods for reading and writing sub-arrays into and out of parallel applications that run on a cluster of workstations. The axial-vectors are replicated and maintained in each node that accesses sub-array elements.

  15. Interaction of fast magnetoacoustic solitons in dense plasmas

    SciTech Connect (OSTI)

    Jahangir, R.; Saleem, Khalid; Masood, W.; Siddiq, M.; Batool, Nazia

    2015-09-15

    One dimensional propagation of fast magnetoacoustic solitary waves in dense plasmas with degenerate electrons is investigated in this paper in the small amplitude limit. In this regard, Korteweg deVries equation is derived and discussed using the plasma parameters that are typically found in white dwarf stars. The interaction of fast magnetoacoustic solitons is explored by using the Hirota bilinear formalism, which admits multi soliton solutions. It is observed that the values of the propagation vectors determine the interaction of solitary waves. It is further noted that the amplitude of the respective solitary waves remain unchanged after the interaction; however, they do experience a phase shift.

  16. Complex Dark Matter

    SciTech Connect (OSTI)

    Lincoln, Don

    2015-04-16

    After a century of study, scientists have come to the realization that the ordinary matter made of atoms is a minority in the universe. In order to explain observations, it appears that there exists a new and undiscovered kind of matter, called dark matter, that is five times more prevalent than ordinary matter. The evidence for this new matter’s existence is very strong, but scientists know only a little about its nature. In today’s video, Fermilab’s Dr. Don Lincoln talks about an exciting and unconventional idea, specifically that dark matter might have a very complex set of structures and interactions. While this idea is entirely speculative, it is an interesting hypothesis and one that scientists are investigating.

  17. Ultrafast electron kinetics in short pulse laser-driven dense hydrogen

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

    Zastrau, U.; Sperling, P.; Fortmann-Grote, C.; Becker, A.; Bornath, T.; Bredow, R.; Doppner, T.; Fennel, T.; Fletcher, L. B.; Forster, E.; et al

    2015-09-25

    Dense cryogenic hydrogen is heated by intense femtosecond infrared laser pulses at intensities ofmore » $${10}^{15}-{10}^{16}\\;$$ W cm–2. Three-dimensional particle-in-cell (PIC) simulations predict that this heating is limited to the skin depth, causing an inhomogeneously heated outer shell with a cold core and two prominent temperatures of about $25$ and $$40\\;\\mathrm{eV}$$ for simulated delay times up to $$+70\\;\\mathrm{fs}$$ after the laser pulse maximum. Experimentally, the time-integrated emitted bremsstrahlung in the spectral range of 8–18 nm was corrected for the wavelength-dependent instrument efficiency. The resulting spectrum cannot be fit with a single temperature bremsstrahlung model, and the best fit is obtained using two temperatures of about 13 and $$30\\;$$eV. The lower temperatures in the experiment can be explained by missing energy-loss channels in the simulations, as well as the inclusion of hot, non-Maxwellian electrons in the temperature calculation. In conclusion, we resolved the time-scale for laser-heating of hydrogen, and PIC results for laser–matter interaction were successfully tested against the experiment data.« less

  18. Ultrafast electron kinetics in short pulse laser-driven dense hydrogen

    SciTech Connect (OSTI)

    Zastrau, U.; Sperling, P.; Fortmann-Grote, C.; Bornath, T.; Bredow, R.; Doppner, T.; Fennel, T.; Fletcher, L. B.; Forster, E.; Gode, S.; Gregori, G.; Harmand, M.; Hilbert, V.; Laarmann, T.; Lee, H. J.; Ma, T.; Meiwes-Broer, K. H.; Mithen, J. P.; Murphy, C. D.; Nakatsutsumi, M.; Neumayer, P.; Przystawik, A.; Skruszewicz, S.; Tiggesbaumker, J.; Toleikis, S.; White, T. G.; Glenzer, S. H.; Redmer, R.; Tschentscher, T.

    2015-09-25

    Dense cryogenic hydrogen is heated by intense femtosecond infrared laser pulses at intensities of ${10}^{15}-{10}^{16}\\;$ W cm–2. Three-dimensional particle-in-cell (PIC) simulations predict that this heating is limited to the skin depth, causing an inhomogeneously heated outer shell with a cold core and two prominent temperatures of about $25$ and $40\\;\\mathrm{eV}$ for simulated delay times up to $+70\\;\\mathrm{fs}$ after the laser pulse maximum. Experimentally, the time-integrated emitted bremsstrahlung in the spectral range of 8–18 nm was corrected for the wavelength-dependent instrument efficiency. The resulting spectrum cannot be fit with a single temperature bremsstrahlung model, and the best fit is obtained using two temperatures of about 13 and $30\\;$eV. The lower temperatures in the experiment can be explained by missing energy-loss channels in the simulations, as well as the inclusion of hot, non-Maxwellian electrons in the temperature calculation. In conclusion, we resolved the time-scale for laser-heating of hydrogen, and PIC results for laser–matter interaction were successfully tested against the experiment data.

  19. Small inner companions of warm Jupiters: Lifetimes and legacies

    SciTech Connect (OSTI)

    Van Laerhoven, Christa; Greenberg, Richard

    2013-12-01

    Although warm Jupiters are generally too far from their stars for tides to be important, the presence of an inner planetary companion to a warm Jupiter can result in tidal evolution of the system. Insight into the process and its effects comes form classical secular theory of planetary perturbations. The lifetime of the inner planet may be shorter than the age of the system, because the warm Jupiter maintains its eccentricity and hence promotes tidal migration into the star. Thus a warm Jupiter observed to be alone in its system might have previously cleared away any interior planets. Before its demise, even if an inner planet is of terrestrial scale, it may promote damping of the warm Jupiter's eccentricity. Thus any inferences of the initial orbit of an observed warm Jupiter must include the possibility of a greater initial eccentricity than would be estimated by assuming it had always been alone. Tidal evolution involving multiple planets also enhances the internal heating of the planets, which readily exceeds that of stellar radiation for the inner planet, and may be great enough to affect the internal structure of warm Jupiters. Secular theory gives insight into the tidal processes, providing, among other things, a way to constrain eccentricities of transiting planets based on estimates of the tidal parameter Q.

  20. A policy synthesis approach for slowing global warming

    SciTech Connect (OSTI)

    Timilsina, G.R.

    1996-12-31

    Global warming is a burning environmental issue today but confronting with subjective as well as policy conflicts. The findings of various studies indicate that developed countries that are capable of affording effective measures towards the global warming mitigation have fewer incentives for doing so because they will have a minimal damage from global warming. The developing countries, although they will have greater damage, are unlikely to divert their development budget for taking preventive actions towards global warming. The only solution in this situation is to design a policy that encourages all the nation in the world to participate in the programs for slowing global warming. Without active participation of all nations, it seems unlikely to reduce the global warming problem in an effective way. This study presents a qualitative policy recommendation extracted from a comprehensive analysis of the findings of several studies conducted so far in this field. This study has categorized the policy approaches for mitigating the global warming in three groups: Engineering approach, forestry approach and economic approach.

  1. Thermophysical properties of multi-shock compressed dense argon

    SciTech Connect (OSTI)

    Chen, Q. F. Zheng, J.; Gu, Y. J.; Chen, Y. L.; Cai, L. C.; Shen, Z. J.

    2014-02-21

    In contrast to the single shock compression state that can be obtained directly via experimental measurements, the multi-shock compression states, however, have to be calculated with the aid of theoretical models. In order to determine experimentally the multiple shock states, a diagnostic approach with the Doppler pins system (DPS) and the pyrometer was used to probe multiple shocks in dense argon plasmas. Plasma was generated by a shock reverberation technique. The shock was produced using the flyer plate impact accelerated up to ∼6.1 km/s by a two-stage light gas gun and introduced into the plenum argon gas sample, which was pre-compressed from the environmental pressure to about 20 MPa. The time-resolved optical radiation histories were determined using a multi-wavelength channel optical transience radiance pyrometer. Simultaneously, the particle velocity profiles of the LiF window was measured with multi-DPS. The states of multi-shock compression argon plasma were determined from the measured shock velocities combining the particle velocity profiles. We performed the experiments on dense argon plasmas to determine the principal Hugonoit up to 21 GPa, the re-shock pressure up to 73 GPa, and the maximum measure pressure of the fourth shock up to 158 GPa. The results are used to validate the existing self-consistent variational theory model in the partial ionization region and create new theoretical models.

  2. Lattice cluster theory for dense, thin polymer films

    SciTech Connect (OSTI)

    Freed, Karl F.

    2015-04-07

    While the application of the lattice cluster theory (LCT) to study the miscibility of polymer blends has greatly expanded our understanding of the monomer scale molecular details influencing miscibility, the corresponding theory for inhomogeneous systems has not yet emerged because of considerable technical difficulties and much greater complexity. Here, we present a general formulation enabling the extension of the LCT to describe the thermodynamic properties of dense, thin polymer films using a high dimension, high temperature expansion. Whereas the leading order of the LCT for bulk polymer systems is essentially simple Flory-Huggins theory, the highly non-trivial leading order inhomogeneous LCT (ILCT) for a film with L layers already involves the numerical solution of 3(L − 1) coupled, highly nonlinear equations for the various density profiles in the film. The new theory incorporates the essential “transport” constraints of Helfand and focuses on the strict imposition of excluded volume constraints, appropriate to dense polymer systems, rather than the maintenance of chain connectivity as appropriate for lower densities and as implemented in self-consistent theories of polymer adsorption at interfaces. The ILCT is illustrated by presenting examples of the computed profiles of the density, the parallel and perpendicular bonds, and the chain ends for free standing and supported films as a function of average film density, chain length, temperature, interaction with support, and chain stiffness. The results generally agree with expected general trends.

  3. Understanding neutron production in the deuterium dense plasma focus

    SciTech Connect (OSTI)

    Appelbe, Brian E-mail: j.chittenden@imperial.ac.uk; Chittenden, Jeremy E-mail: j.chittenden@imperial.ac.uk

    2014-12-15

    The deuterium Dense Plasma Focus (DPF) can produce copious amounts of MeV neutrons and can be used as an efficient neutron source. However, the mechanism by which neutrons are produced within the DPF is poorly understood and this limits our ability to optimize the device. In this paper we present results from a computational study aimed at understanding how neutron production occurs in DPFs with a current between 70 kA and 500 kA and which parameters can affect it. A combination of MHD and kinetic tools are used to model the different stages of the DPF implosion. It is shown that the anode shape can significantly affect the structure of the imploding plasma and that instabilities in the implosion lead to the generation of large electric fields at stagnation. These electric fields can accelerate deuterium ions within the stagnating plasma to large (>100 keV) energies leading to reactions with ions in the cold dense plasma. It is shown that the electromagnetic fields present can significantly affect the trajectories of the accelerated ions and the resulting neutron production.

  4. PROCEEDINGS OF RIKEN/BNL RESEARCH CENTER WORKSHOP, EQUILIBRIUM AND NON-EQUILIBRIM ASPECTS OF HOT, DENSE QCD, VOLUME 28.

    SciTech Connect (OSTI)

    De Vega, H.J.; Boyanovsky, D.

    2000-07-17

    The Relativistic Heavy Ion Collider (RHIC) at Brookhaven, beginning operation this year, and the Large Hadron Collider (LHC) at CERN, beginning operation {approximately}2005, will provide an unprecedented range of energies and luminosities that will allow us to probe the Gluon-Quark plasma. At RHIC and LHC, at central rapidity typical estimates of energy densities and temperatures are e * 1-10 GeV/fm3 and T0 * 300 - 900 MeV. Such energies are well above current estimates for the GQ plasma. Initially, this hot, dense plasma is far from local thermal equilibrium, making the theoretical study of transport phenomena, kinetic and chemical equilibration in dense and hot plasmas, and related issues a matter of fundamental importance. During the last few years a consistent framework to study collective effects in the Gluon-Quark plasma, and a microscopic description of transport in terms of the hard thermal (and dense) loops resummation program has emerged. This approach has the potential of providing a microscopic formulation of transport, in the regime of temperatures and densities to be achieved at RHIC and LHC. A parallel development over the last few years has provided a consistent formulation of non-equilibrium quantum field theory that provides a real-time description of phenomena out of equilibrium. Novel techniques including non-perturbative approaches and the dynamical renormalization group techniques lead to new insights into transport and relaxation. A deeper understanding of collective.excitations and transport phenomena in the GQ plasma could lead to recognize novel potential experimental signatures. New insights into small-c physics reveals a striking similarity between small-c and hard thermal loops, and novel real-time numerical simulations have recently studied the parton distributions and their thermalizations in the initial stages of a heavy ion collision.

  5. PROCEEDINGS OF RIKEN/BNL RESEARCH CENTER WORKSHOP, EQUILIBRIUM AND NON-EQUILIBRIM ASPECTTS OF HOT, DENSE QCD, VOLUME 28.

    SciTech Connect (OSTI)

    DE VEGA,H.J.; BOYANOVSKY,D.

    2000-07-17

    The Relativistic Heavy Ion Collider (RHIC) at Brookhaven, beginning operation this year, and the Large Hadron Collider (LHC) at CERN, beginning operation {approximately}2005, will provide an unprecedented range of energies and luminosities that will allow us to probe the Gluon-Quark plasma. At RHIC and LHC, at central rapidity typical estimates of energy densities and temperatures are e * 1-10 GeV/fm3 and T0 * 300 - 900 MeV. Such energies are well above current estimates for the GQ plasma. Initially, this hot, dense plasma is far from local thermal equilibrium, making the theoretical study of transport phenomena, kinetic and chemical equilibration in dense and hot plasmas, and related issues a matter of fundamental importance. During the last few years a consistent framework to study collective effects in the Gluon-Quark plasma, and a microscopic description of transport in terms of the hard thermal (and dense) loops resummation program has emerged. This approach has the potential of providing a microscopic formulation of transport, in the regime of temperatures and densities to be achieved at RHIC and LHC. A parallel development over the last few years has provided a consistent formulation of non-equilibrium quantum field theory that provides a real-time description of phenomena out of equilibrium. Novel techniques including non-perturbative approaches and the dynamical renormalization group techniques lead to new insights into transport and relaxation. A deeper understanding of collective.excitations and transport phenomena in the GQ plasma could lead to recognize novel potential experimental signatures. New insights into small-c physics reveals a striking similarity between small-c and hard thermal loops, and novel real-time numerical simulations have recently studied the parton distributions and their thermalizations in the initial stages of a heavy ion collision.

  6. Rising Sea Levels Due to Global Warming Are Unstoppable

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

    Rising Sea Levels Due to Global Warming Are Unstoppable Rising Sea Levels Due to Global Warming Are Unstoppable Mitigation can slow down but not prevent sea level rise for centuries to come August 5, 2013 Contact: Linda Vu, Lvu@lbl.gov, +1 510 495 2402 washington.jpg Because seawater absorbs heat more slowly than the atmosphere above it, our oceans won't feel the full impact of the greenhouse gases already in the air for hundreds of years. Warm water expands, raising sea levels. (Courtesy W.

  7. Cold weather encourages warm hearts in Kansas City | National Nuclear

    National Nuclear Security Administration (NNSA)

    Security Administration | (NNSA) Cold weather encourages warm hearts in Kansas City Tuesday, January 19, 2016 - 12:00am NNSA Blog Most of us just reach into the closet to pull on a warm coat to shield us from the winter weather, but for thousands of needy children in the Kansas City area who have outgrown their coats, it's not so simple. Thanks to the Coats for Kids program, which provides new and gently used coats for children who need them, many of these children will be toasty warm. Each

  8. Measuring and Mitigating Urban Warming in a Northern Metropolitan Area |

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

    Argonne Leadership Computing Facility Measuring and Mitigating Urban Warming in a Northern Metropolitan Area Event Sponsor: Environmental Science Seminar Start Date: Aug 25 2016 - 11:00am Building/Room: Building 240/Room 4301 Location: Argonne National Laboratory Speaker(s): Peter Snyder Speaker(s) Title: University of Minnesota In the United States and much of the rest of the world, cities are warming at twice the rate of outlying rural areas and the planet as a whole. While the warming can

  9. WARM MOLECULAR GAS IN LUMINOUS INFRARED GALAXIES

    SciTech Connect (OSTI)

    Lu, N.; Zhao, Y.; Xu, C. K.; Mazzarella, J. M.; Howell, J.; Appleton, P.; Lord, S.; Schulz, B.; Gao, Y.; Armus, L.; Daz-Santos, T.; Surace, J.; Isaak, K. G.; Petric, A. O.; Charmandaris, V.; Evans, A. S.; Inami, H.; Iwasawa, K.; Leech, J.; Sanders, D. B.; and others

    2014-06-01

    We present our initial results on the CO rotational spectral line energy distribution (SLED) of the J to J1 transitions from J = 4 up to 13 from Herschel SPIRE spectroscopic observations of 65 luminous infrared galaxies (LIRGs) in the Great Observatories All-Sky LIRG Survey. The observed SLEDs change on average from one peaking at J ? 4 to a broad distribution peaking around J ? 6 to 7 as the IRAS 60-to-100?m color, C(60/100), increases. However, the ratios of a CO line luminosity to the total infrared luminosity, L {sub IR}, show the smallest variation for J around 6 or 7. This suggests that, for most LIRGs, ongoing star formation (SF) is also responsible for a warm gas component that emits CO lines primarily in the mid-J regime (5 ? J ? 10). As a result, the logarithmic ratios of the CO line luminosity summed over CO(54), (65), (76), (87) and (109) transitions to L {sub IR}, log R {sub midCO}, remain largely independent of C(60/100), and show a mean value of 4.13 (?log?R{sub midCO}{sup SF}) and a sample standard deviation of only 0.10 for the SF-dominated galaxies. Including additional galaxies from the literature, we show, albeit with a small number of cases, the possibility that galaxies, which bear powerful interstellar shocks unrelated to the current SF, and galaxies, in which an energetic active galactic nucleus contributes significantly to the bolometric luminosity, have their R {sub midCO} higher and lower than R{sub midCO}{sup SF}, respectively.

  10. Denitrifying and diazotrophic community responses to artificial warming in permafrost and tallgrass prairie soils

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

    Penton, Christopher R.; St. Louis, Derek; Pham, Amanda; Cole, James R.; Wu, Liyou; Luo, Yiqi; Schuur, E. A. G.; Zhou, Jizhong; Tiedje, James M.

    2015-07-21

    Increasing temperatures have been shown to impact soil biogeochemical processes, although the corresponding changes to the underlying microbial functional communities are not well understood. Alterations in the nitrogen (N) cycling functional component are particularly important as N availability can affect microbial decomposition rates of soil organic matter and influence plant productivity. To assess changes in the microbial component responsible for these changes, the composition of the N-fixing (nifH), and denitrifying (nirS, nirK, nosZ) soil microbial communities was assessed by targeted pyrosequencing of functional genes involved in N cycling in two major biomes where the experimental effect of climate warming ismore » under investigation, a tallgrass prairie in Oklahoma (OK) and the active layer above permafrost in Alaska (AK). Raw reads were processed for quality, translated with frameshift correction, and a total of 313,842 amino acid sequences were clustered and linked to a nearest neighbor using reference datasets. The number of OTUs recovered ranged from 231 (NifH) to 862 (NirK). The N functional microbial communities of the prairie, which had experienced a decade of experimental warming were the most affected with changes in the richness and/or overall structure of NifH, NirS, NirK and NosZ. In contrast, the AK permafrost communities, which had experienced only 1 year of warming, showed decreased richness and a structural change only with the nirK-harboring bacterial community. A highly divergent nirK-harboring bacterial community was identified in the permafrost soils, suggesting much novelty, while other N functional communities exhibited similar relatedness to the reference databases, regardless of site. Lastly, prairie and permafrost soils also harbored highly divergent communities due mostly to differing major populations.« less