Sample records for international thermonuclear experimental

  1. ITER --"INTERNATIONAL THERMONUCLEAR EXPERIMENTAL RESEARCH PROGRAM".

    E-Print Network [OSTI]

    ITER -- "INTERNATIONAL THERMONUCLEAR EXPERIMENTAL RESEARCH PROGRAM". ORGANIZATION TO DIRECT WORLD plasmas and thermonuclear burn processes (cost -$1.5-36)2. (2) An expanded, more ambitious international Thermonuclear Experimental Research Program" by L. J. Perkins #12;NORMAL-CONDUCTING COPPER OPTIONS FOR THE ITER

  2. TRANSP simulations of International Thermonuclear Experimental Reactor plasmas

    E-Print Network [OSTI]

    Budny, Robert

    TRANSP simulations of International Thermonuclear Experimental Reactor plasmas R. V. Budny, D. C-consistent models for plasmas within the separatrix surface in the International Thermonuclear Experimental Reactor. INTRODUCTION One of the goals for the International Thermonuclear Experimental Reactor ITER is the production

  3. PUBLISHED VERSION Design, performance, and grounding aspects of the International Thermonuclear Experimental

    E-Print Network [OSTI]

    PUBLISHED VERSION Design, performance, and grounding aspects of the International Thermonuclear, performance, and grounding aspects of the International Thermonuclear Experimental Reactor ion cyclotron range Thermonuclear Experimental Reactor ion cyclotron range of frequencies antenna F. Durodie,1,a) P. Dumortier,1 M

  4. Industrial opportunities on the International Thermonuclear Experimental Reactor (ITER) project

    SciTech Connect (OSTI)

    Ellis, W.R. [Raytheon Engineers and Constructors, New York, NY (United States)

    1996-12-01T23:59:59.000Z

    Industry has been a long-term contributor to the magnetic fusion program, playing a variety of important roles over the years. Manufacturing firms, engineering-construction companies, and the electric utility industry should all be regarded as legitimate stakeholders in the fusion energy program. In a program focused primarily on energy production, industry`s future roles should follow in a natural way, leading to the commercialization of the technology. In a program focused primarily on science and technology, industry`s roles, in the near term, should be, in addition to operating existing research facilities, largely devoted to providing industrial support to the International Thermonuclear Experimental Reactor (ITER) Project. Industrial opportunities on the ITER Project will be guided by the amount of funding available to magnetic fusion generally, since ITER is funded as a component of that program. The ITER Project can conveniently be discussed in terms of its phases, namely, the present Engineering Design Activities (EDA) phase, and the future (as yet not approved) construction phase. 2 refs., 3 tabs.

  5. ITER: The International Thermonuclear Experimental Reactor and the Nuclear Weapons Proliferation

    E-Print Network [OSTI]

    André Gsponer; Jean-pierre Hurni

    2004-01-01T23:59:59.000Z

    militarytechnical reasons and implications of the very probable siting of ITER (the International Thermonuclear

  6. ITER: The International Thermonuclear Experimental Reactor and the Nuclear Weapons Proliferation Implications of Thermonuclear-Fusion Energy Systems

    E-Print Network [OSTI]

    André Gsponer; Jean-pierre Hurni

    2004-01-01T23:59:59.000Z

    This paper contains two parts: (I) A list of “points ” highlighting the strategic-political and militarytechnical reasons and implications of the very probable siting of ITER (the International Thermonuclear Experimental Reactor) in Japan, which should be confirmed sometimes in early 2004. (II) A technical analysis of the nuclear weapons proliferation implications of inertial- and magnetic-confinement fusion systems substantiating the technical points highlighted in the first part, and showing that while full access to the physics of thermonuclear weapons is the main implication of ICF, full access to large-scale tritium technology is the main proliferation impact of MCF. The conclusion of the paper is that siting ITER in a country such as Japan, which already has a large separated-plutonium stockpile, and an ambitious laser-driven ICF program (comparable in size and quality to those of the United States or France) will considerably increase its latent (or virtual) nuclear weapons proliferation status, and foster further nuclear proliferation throughout the world. The safety and environmental problems related to the operation of largescale fusion facilities such as ITER (which contain massive amounts of hazardous and/or radioactive materials such as tritium, lithium, and beryllium, as well as neutron-activated structural materials) are not addressed in this paper.

  7. US ITER (International Thermonuclear Experimental Reactor) shield and blanket design activities

    SciTech Connect (OSTI)

    Baker, C.C.

    1988-08-01T23:59:59.000Z

    This paper summarizes nuclear-related work in support of the US effort for the International Thermonuclear Experimental Reactor (ITER) Study. Primary tasks carried out during the past year include design improvements of the inboard shield developed for the TIBER concept, scoping studies of a variety of tritium breeding blanket options, development of necessary design guidelines and evaluation criteria for the blanket options, further safety considerations related to nuclear components, and issues regarding structural materials for an ITER device. The blanket concepts considered are the aqueous/Li salt solution, a water-cooled, solid breeder blanket, a helium-cooled, solid-breeder blanket, a blanket cooled by helium containing lithium-bearing particulates, and a blanket concept based on breeding tritium from He/sup 3/. 1 ref., 2 tabs.

  8. Review of the International Thermonuclear Experimental Reactor (ITER) detailed design report

    SciTech Connect (OSTI)

    NONE

    1997-04-18T23:59:59.000Z

    Dr. Martha Krebs, Director, Office of Energy Research at the US Department of Energy (DOE), wrote to the Fusion Energy Sciences Advisory Committee (FESAC), in letters dated September 23 and November 6, 1996, requesting that FESAC review the International Thermonuclear Experimental Reactor (ITER) Detailed Design Report (DDR) and provide its view of the adequacy of the DDR as part of the basis for the United States decision to enter negotiations with the other interested Parties regarding the terms and conditions for an agreement for the construction, operations, exploitation and decommissioning of ITER. The letter from Dr. Krebs, referred to as the Charge Letter, provided context for the review and a set of questions of specific interest.

  9. ROLE OF FUSION ENERGY FOR THE 21 CENTURY ENERGY MARKET AND DEVELOPMENT STRATEGY WITH INTERNATIONAL THERMONUCLEAR EXPERIMENTAL

    E-Print Network [OSTI]

    THERMONUCLEAR EXPERIMENTAL REACTOR Rôle de l'énergie de fusion dans la production énergétique du 21 e siècle etROLE OF FUSION ENERGY FOR THE 21 CENTURY ENERGY MARKET AND DEVELOPMENT STRATEGY WITH INTERNATIONAL be improved to contribute to this issue. Fusion is an energy source of the Sun and the Star. It is a quite

  10. Economic impacts on the United States of siting decisions for the international thermonuclear experimental reactor

    SciTech Connect (OSTI)

    Peerenboom, J.P.; Hanson, M.E.; Huddleston, J.R. [and others

    1996-08-01T23:59:59.000Z

    This report presents the results of a study that examines and compares the probable short-term economic impacts of the International Thermonuclear Experimental Reactor (ITER) on the United States (U.S.) if (1) ITER were to be sited in the U.S., or (2) ITER were to be sited in one of the other countries that, along with the U.S., is currently participating in the ITER program. Life-cycle costs associated with ITER construction, operation, and decommissioning are analyzed to assess their economic impact. A number of possible U.S. host and U.S. non-host technology and cost-sharing arrangements with the other ITER Parties are examined, although cost-sharing arrangements and the process by which the Parties will select a host country and an ITER site remain open issues. Both national and local/regional economic impacts, as measured by gross domestic product, regional output, employment, net exports, and income, are considered. These impacts represent a portion of the complex, interrelated set of economic considerations that characterize U.S. host and U.S. non-host participation in ITER. A number of other potentially important economic and noneconomic considerations are discussed qualitatively.

  11. The Japan Times Printer Friendly Articles France has won the competition to host the International Thermonuclear Experimental Reactor (ITER), the world's first nuclear-

    E-Print Network [OSTI]

    the International Thermonuclear Experimental Reactor (ITER), the world's first nuclear- fusion reactor. Japan fought wins by withdrawing ITER bid Thermonuclear fusion utilizes the same process that powers the sun -- nuclear-fusion reactions -- to produce energy. Scientists at the ITER plant will create nuclear-fusion

  12. First operation with the JET International Thermonuclear Experimental Reactor-like wall

    SciTech Connect (OSTI)

    Neu, R. [EFDA-CSU, Boltzmannstr. 2, 85748 Garching (Germany) [EFDA-CSU, Boltzmannstr. 2, 85748 Garching (Germany); Max-Planck-Institut für Plasmaphysik, Euratom Association, Boltzmannstr. 2, 85748 Garching (Germany); Arnoux, G.; Beurskens, M.; Challis, C.; Giroud, C.; Lomas, P.; Maddison, G.; Matthews, G.; Mayoral, M.-L.; Meigs, A.; Rimini, F. [Euratom/CCFE Fusion Association, Culham Science Centre, Abingdon OX14 3DB (United Kingdom)] [Euratom/CCFE Fusion Association, Culham Science Centre, Abingdon OX14 3DB (United Kingdom); Bobkov, V.; Dux, R.; Hobirk, J.; Lang, P.; Maggi, C.; Pütterich, T.; Sertoli, M.; Sieglin, B. [Max-Planck-Institut für Plasmaphysik, Euratom Association, Boltzmannstr. 2, 85748 Garching (Germany)] [Max-Planck-Institut für Plasmaphysik, Euratom Association, Boltzmannstr. 2, 85748 Garching (Germany); Brezinsek, S. [IEK-4, Association EURATOM/Forschungszentrum Jülich GmbH, Jülich 52425 (Germany)] [IEK-4, Association EURATOM/Forschungszentrum Jülich GmbH, Jülich 52425 (Germany); and others

    2013-05-15T23:59:59.000Z

    To consolidate International Thermonuclear Experimental Reactor (ITER) design choices and prepare for its operation, Joint European Torus (JET) has implemented ITER's plasma facing materials, namely, Be for the main wall and W in the divertor. In addition, protection systems, diagnostics, and the vertical stability control were upgraded and the heating capability of the neutral beams was increased to over 30 MW. First results confirm the expected benefits and the limitations of all metal plasma facing components (PFCs) but also yield understanding of operational issues directly relating to ITER. H-retention is lower by at least a factor of 10 in all operational scenarios compared to that with C PFCs. The lower C content (? factor 10) has led to much lower radiation during the plasma burn-through phase eliminating breakdown failures. Similarly, the intrinsic radiation observed during disruptions is very low, leading to high power loads and to a slow current quench. Massive gas injection using a D{sub 2}/Ar mixture restores levels of radiation and vessel forces similar to those of mitigated disruptions with the C wall. Dedicated L-H transition experiments indicate a 30% power threshold reduction, a distinct minimum density, and a pronounced shape dependence. The L-mode density limit was found to be up to 30% higher than for C allowing stable detached divertor operation over a larger density range. Stable H-modes as well as the hybrid scenario could be re-established only when using gas puff levels of a few 10{sup 21} es{sup ?1}. On average, the confinement is lower with the new PFCs, but nevertheless, H factors up to 1 (H-Mode) and 1.3 (at ?{sub N}?3, hybrids) have been achieved with W concentrations well below the maximum acceptable level.

  13. Progress in preparing scenarios for operation of the International Thermonuclear Experimental Reactor

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

    Sips, A. C. C.; Giruzzi, G.; Ide, S.; Kessel, C.; Luce, T. C.; Snipes, J. A.; Stober, J. K.

    2015-02-01T23:59:59.000Z

    The development of operating scenarios is one of the key issues in the research for ITER which aims to achieve a fusion gain (Q) of ~10, while producing 500MW of fusion power for ?300 s. The ITER Research plan proposes a success oriented schedule starting in hydrogen and helium, to be followed by a nuclear operation phase with a rapid development towards Q ~ 10 in deuterium/tritium. The Integrated Operation Scenarios Topical Group of the International Tokamak Physics Activity initiates joint activities among worldwide institutions and experiments to prepare ITER operation. Plasma formation studies report robust plasma breakdown in devicesmore »with metal walls over a wide range of conditions, while other experiments use an inclined EC launch angle at plasma formation to mimic the conditions in ITER. Simulations of the plasma burn-through predict that at least 4MW of Electron Cyclotron heating (EC) assist would be required in ITER. For H-modes at q??~ 3, many experiments have demonstrated operation with scaled parameters for the ITER baseline scenario at ne/nGW ~ 0.85. Most experiments, however, obtain stable discharges at H??(y,2) ~ 1.0 only for bN = 2.0–2.2. For the rampup in ITER, early X-point formation is recommended, allowing auxiliary heating to reduce the flux consumption. A range of plasma inductance (li(3)) can be obtained from 0.65 to 1.0, with the lowest values obtained in H-mode operation. For the rampdown, the plasma should stay diverted maintaining H-mode together with a reduction of the elongation from 1.85 to 1.4. Simulations show that the proposed rampup and rampdown schemes developed since 2007 are compatible with the present ITER design for the poloidal field coils. At 13–15 MA and densities down to ne/nGW ~ 0.5, long pulse operation (>1000 s) in ITER is possible at Q ~ 5, useful to provide neutron fluence for Test Blanket Module assessments. ITER scenario preparation in hydrogen and helium requires high input power (>50 MW). H-mode operation in helium may be possible at input powers above 35MW at a toroidal field of 2.65T, for studying H-modes and ELM mitigation. In hydrogen, H-mode operation is expected to be marginal, even at 2.65T with 60MW of input power. Simulation code benchmark studies using hybrid and steady state scenario parameters have proved to be a very challenging and lengthy task of testing suites of codes, consisting of tens of sophisticated modules. Nevertheless, the general basis of the modelling appears sound, with substantial consistency among codes developed by different groups. For a hybrid scenario at 12 MA, the code simulations give a range for Q = 6.5–8.3, using 30MW neutral beam injection and 20MW ICRH. For non-inductive operation at 7–9 MA, the simulation results show more variation. At high edge pedestal pressure (Tped ~ 7 keV), the codes predict Q = 3.3–3.8 using 33MW NB, 20MW EC, and 20MW ion cyclotron to demonstrate the feasibility of steady-state operation with the day-1 heating systems in ITER. Simulations using a lower edge pedestal temperature (~3 keV) but improved core confinement obtain Q = 5–6.5, when ECCD is concentrated at mid-radius and ~ 20MW off-axis current drive (ECCD or LHCD) is added. Several issues remain to be studied, including plasmas with dominant electron heating, mitigation of transient heat loads integrated in scenario demonstrations and (burn) control simulations in ITER scenarios.« less

  14. A E Costley, US/ITER Town meeting, San Diego, 22 April 2004 N 55 IP 57 04-04-30 F 1 International Thermonuclear Experimental Reactor

    E-Print Network [OSTI]

    Thermonuclear Experimental Reactor Overview of ITER Diagnostics and Progress Towards Procurement A E Costley/C) Reflectometers for Divertor Plasma Optical/IR Systems Fast Wave Reflectometry (N/C) Thomson Scattering (Core Interferom./Polarimetric System Residual Gas Analyzers Polarimetric System (Pol. Field Meas) IR Thermography

  15. Implications of Thermonuclear-Fusion Energy Systems

    E-Print Network [OSTI]

    André Gsponer; Jean-pierre Hurni

    2004-01-01T23:59:59.000Z

    militarytechnical reasons and implications of the very probable siting of ITER (the International Thermonuclear

  16. Thermonuclear fusion

    E-Print Network [OSTI]

    Thermonuclear fusion is a way to achieve nuclear fusion by using extremely high temperatures. There are two forms of thermonuclear fusion: uncontrolled, in which the resulting energy is released in an uncontrolled manner, as it is in thermonuclear weapon...

  17. http://www3.nhk.or.jp/news/2003/12/27/k20031227000018.html 3 national visits related to proposed site for experimental reactor

    E-Print Network [OSTI]

    Minister communication meeting on Japanese Proposed site for Thermonuclear fusion experimental reactor realize the Japanese proposed site for the international thermonuclear fusion experimental reactor (ITER international support for experimental reactor ITER of the fusion centering on proposed site in Aomori

  18. Feedback control of major disruptions in International Thermonuclear Experimental Reactor

    SciTech Connect (OSTI)

    Sen, A. K. [Plasma Physics Laboratory, Columbia University, New York, New York 10026 (United States)

    2011-08-15T23:59:59.000Z

    It is argued that major disruptions in ITER can be avoided by the feedback control of the causative MHD precursors. The sensors will be 2D-arrays of ECE detectors and the suppressors will be modulated ECH beams injected radially to produce non-thermal radial pressures to counter the radial dynamics of MHD modes. The appropriate amplitude and phase of this signal can stabilize the relevant MHD modes and prevent their evolution to a major disruption. For multimode MHD precursors, an optimal feedback scheme with a Kalman filter is discussed.

  19. 03/01/2006 09:51 AMLoading "People's Daily Online --Chinese experimental thermonuclear reactor on discharge test in July" Page 1 of 1http://english.people.com.cn/200603/01/print20060301_247035.html

    E-Print Network [OSTI]

    experimental thermonuclear reactor on discharge test in July China's new generation experimental Tokamak fusion03/01/2006 09:51 AMLoading "People's Daily Online -- Chinese experimental thermonuclear reactor successful, it would be the world's first experimental nuclear fusion device to come into operation. Li

  20. Astrophysical thermonuclear functions

    E-Print Network [OSTI]

    W. J. Anderson; H. J. Haubold; A. M. Mathai

    1994-02-08T23:59:59.000Z

    As theoretical knowledge and experimental verification of nuclear cross sections increases it becomes possible to refine analytic representations for nuclear reaction rates. In this paper mathematical/statistical techniques for deriving closed-form representations of thermonuclear functions are summarized and numerical results for them are given.The purpose of the paper is also to compare numerical results for approximate and closed-form representations of thermonuclear functions.

  1. Astrophysical thermonuclear functions

    E-Print Network [OSTI]

    William J. Anderson; Hans J. Haubold; Arak Mathai Mathai

    1993-08-23T23:59:59.000Z

    Stars are gravitationally stabilized fusion reactors changing their chemical composition while transforming light atomic nuclei into heavy ones. The atomic nuclei are supposed to be in thermal equilibrium with the ambient plasma. The majority of reactions among nuclei leading to a nuclear transformation are inhibited by the necessity for the charged participants to tunnel through their mutual Coulomb barrier. As theoretical knowledge and experimental verification of nuclear cross sections increases it becomes possible to refine analytic representations for nuclear reaction rates. Over the years various approaches have been made to derive closed-form representations of thermonuclear reaction rates (Critchfield 1972, Haubold and John 1978, Haubold, Mathai and Anderson 1987). They show that the reaction rate contains the astrophysical cross section factor and its derivatives which has to be determined experimentally, and an integral part of the thermonuclear reaction rate independent from experimental results which can be treated by closed-form representation techniques in terms of generalized hypergeometric functions. In this paper mathematical/statistical techniques for deriving closed-form representations of thermonuclear functions will be summarized and numerical results for them will be given. The separation of thermonuclear functions from thermonuclear reaction rates is our preferred result. The purpose of the paper is also to compare numerical results for approximate and closed-form representations of thermonuclear functions. This paper completes the work of Haubold, Mathai, and Anderson (1987).

  2. alamos thermonuclear weapon: Topics by E-print Network

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

    Thermonuclear Experimental Reactor and the Nuclear Weapons Proliferation Implications of Thermonuclear-Fusion Energy Systems CiteSeer Summary: This paper contains two parts: (I) A...

  3. aspects experimental developments: Topics by E-print Network

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

    Amit 10 PUBLISHED VERSION Design, performance, and grounding aspects of the International Thermonuclear Experimental Plasma Physics and Fusion Websites Summary: PUBLISHED VERSION...

  4. Thermonuclear Supernovae

    E-Print Network [OSTI]

    F. K. Roepke

    2008-04-14T23:59:59.000Z

    The application of Type Ia supernovae (SNe Ia) as distance indicators in cosmology calls for a sound understanding of these objects. Recent years have seen a brisk development of astrophysical models which explain SNe Ia as thermonuclear explosions of white dwarf stars. While the evolution of the progenitor is still uncertain, the explosion mechanism certainly involves the propagation of a thermonuclear flame through the white dwarf star. Three-dimensional hydrodynamical simulations allowed to study a wide variety of possibilities involving subsonic flame propagation (deflagrations), flames accelerated by turbulence, and supersonic detonations. These possibilities lead to a variety of scenarios. I review the currently discussed approaches and present some recent results from simulations of the turbulent deflagration model and the delayed detonation model.

  5. New concept for internal heat production in hot Jupiter exo-planets, thermonuclear ignition of dark

    E-Print Network [OSTI]

    J. Marvin Herndon

    2008-01-01T23:59:59.000Z

    Discovery of hot Jupiter exo-planets, those with anomalously inflated size and low density relative to Jupiter, has evoked much discussion as to possible sources of internal heat production. But to date, no explanations have come forth that are generally applicable. The explanations advanced typically involve presumed tidal dissipation and/or converted incident stellar radiation. The present, brief communication suggests a novel interfacial nuclear fission-fusion source of internal heat production for hot Jupiters that has been overlooked by theoreticians and which has potentially general applicability.

  6. ASTROPHYSICAL THERMONUCLEAR FUNCTIONS

    E-Print Network [OSTI]

    W. J. Anderson; H. J. Haubold; A. M. Mathai

    1993-01-01T23:59:59.000Z

    approaches have been made to derive closed-form representations of thermonuclear reaction rates (Critchfield

  7. Experimental measurements of the O15(alpha,gamma)Ne19 reaction rate and the stability of thermonuclear burning on accreting neutron stars

    E-Print Network [OSTI]

    Jacob Lund Fisker; Wanpeng Tan; Joachim Goerres; Michael Wiescher; Randall L. Cooper

    2007-05-07T23:59:59.000Z

    Neutron stars in close binary star systems often accrete matter from their companion stars. Thermonuclear ignition of the accreted material in the atmosphere of the neutron star leads to a thermonuclear explosion which is observed as an X-ray burst occurring periodically between hours and days depending on the accretion rate. The ignition conditions are characterized by a sensitive interplay between the accretion rate of the fuel supply and its depletion rate by nuclear burning in the hot CNO cycle and the rp-process. For accretion rates close to stable burning the burst ignition therefore depends critically on the hot CNO breakout reaction, O15(alpha,gamma)Ne19, that regulates the flow between the hot CNO cycle and the rapid proton capture process. Until recently, the O15(alpha,gamma)Ne19-reaction rate was not known experimentally and the theoretical estimates carried significant uncertainties. In this paper we perform a parameter study of the uncertainty of this reaction rate and determine the astrophysical consequences of the first measurement of this reaction rate. Our results corroborate earlier predictions and show that theoretically burning remains unstable up to accretion rates near the Eddington limit, in contrast to astronomical observations.

  8. Radiation-Resistant WDM Optical Link for Thermonuclear Fusion Reactor Instrumentation

    E-Print Network [OSTI]

    A. Fernandez Fernandez; Ez Fern; P. Borgermans; B. Brichard; P. Borgermans; A. I. Gusarov; M. Van Uffelen; P. Megret; M. Decréton; M. Blondel; A. Delchambre

    2001-01-01T23:59:59.000Z

    The future International Thermonuclear Experimental Reactor (ITER) is a complex installation that will require permanent monitoring and frequent maintenance operations. The high-gamma dose rates, the high neutron fluence, and other radiological hazards call for the use of remote-handled equipment

  9. astrophysical thermonuclear reactions: Topics by E-print Network

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

    well as experimental investigations are motivated. T. Rauscher 1998-10-15 4 Astrophysical thermonuclear functions Astrophysics (arXiv) Summary: Stars are gravitationally stabilized...

  10. Physics modeling support for the International Thermonuclear Experimental Reactor: Final report

    SciTech Connect (OSTI)

    Not Available

    1988-09-30T23:59:59.000Z

    There are two major sections to this report. The first section of the report is an executive summary of the work done this year. For each task, the major results are condensed for the reader's convenience. The major result of each memo, report or presentation is summarized briefly in this section. The second section of the report is a collection of appendices containing reports, memos, and presentations written this year. Here, the interested reader can investigate any topic discussed in the summary in more detail. The documentation is presented in chronological order, and we would like to note that the content of later documents may supercede that of earlier ones. The summaries are divided into sections, corresponding to the tasks outlined in the original proposal for the work. These sections are: MUMAK code development and application; Alfven wave stability problem; TETRA systems code development and application; lower hybrid heating and current drive; and advanced blanket modeling.

  11. ITER vacuum vessel fabrication plan and cost study (D 68) for the international thermonuclear experimental reactor

    SciTech Connect (OSTI)

    NONE

    1995-01-01T23:59:59.000Z

    ITER Task No. 8, Vacuum Vessel Fabrication Plan and Cost Study (D68), was initiated to assess ITER vacuum vessel fabrication, assembly, and cost. The industrial team of Raytheon Engineers & Constructors and Chicago Bridge & Iron (Raytheon/CB&I) reviewed the current vessel basis and prepared a manufacturing plan, assembly plan, and cost estimate commensurate with the present design. The guidance for the Raytheon/CB&I assessment activities was prepared by the ITER Garching Work Site. This guidance provided in the form of work descriptions, sketches, drawings, and costing guidelines for each of the presently identified vacuum vessel Work Breakdown Structure (WBS) elements was compiled in ITER Garching Joint Work Site Memo (Draft No. 9 - G 15 MD 01 94-17-05 W 1). A copy of this document is provided as Appendix 1 to this report. Additional information and clarifications required for the Raytheon/CB&I assessments were coordinated through the US Home Team (USHT) and its technical representative. Design details considered essential to the Task 8 assessments but not available from the ITER Joint Central Team (JCT) were generated by Raytheon/CB&I and documented accordingly.

  12. IN TODAY'S PAPER International

    E-Print Network [OSTI]

    India's participation in the multi-billion-dollar International Thermonuclear Reactor project which aims

  13. Nucleosynthesis in Thermonuclear Supernovae

    SciTech Connect (OSTI)

    Claudia, Travaglio [Istituto Nazionale di Astrofisica, Osservatorio Astronomico di Torino; Hix, William Raphael [ORNL

    2013-01-01T23:59:59.000Z

    We review our understanding of the nucleosynthesis that occurs in thermonuclear supernovae and their contribution to Galactic Chemical evolution. We discuss the prospects to improve the modeling of the nucleosynthesis within simulations of these events.

  14. Elastic-plastic analysis of the transition divertor joint for high performance divertor target plate

    E-Print Network [OSTI]

    Navaei, Dara

    2011-01-01T23:59:59.000Z

    CER) 8. International Thermonuclear Experimental Reactor (to International Thermonuclear Experimental Reactor (International Thermonuclear Experimental Reactor (ITER) is a

  15. Thermonuclear reactor may begin to be built 2004 21.02.2004, 00.55

    E-Print Network [OSTI]

    Thermonuclear reactor may begin to be built 2004 21.02.2004, 00.55 MOSCOW, February 20 (Itar-Tass) -- Construction of what may become the world's first-ever thermonuclear experimental reactor (ITER) may begin Institute, which developed the thermonuclear reactor, Yevgeny Velikhov said. The Russian panel at the Vienna

  16. Prediction of Thermonuclear Reaction Rates in Astrophysics

    E-Print Network [OSTI]

    T. Rauscher

    1998-10-15T23:59:59.000Z

    Recent improvements and remaining problems in the prediction of thermonuclear rates are reviewed. The main emphasis is on statistical model calculations, but the challenge to include direct reactions close to the driplines is also briefly addressed. Further theoretical as well as experimental investigations are motivated.

  17. Thermonuclear Ignition of Dark Galaxies

    E-Print Network [OSTI]

    J. Marvin Herndon

    2006-01-01T23:59:59.000Z

    thermonuclear ignition of stars by nuclear fission, and the corollary, non-ignition of stars. The possibility of

  18. Macroscopic implications from phase space dynamics of tokamak turbulence : relaxation, transport, and flow generation

    E-Print Network [OSTI]

    Kosuga, Yusuke

    2012-01-01T23:59:59.000Z

    for the International Thermonuclear Experimental Reactor (for the International Thermonuclear Experimental Reactor (

  19. A high-speed beam of lithium droplets for collecting diverted energy and particles in ITER (International Thermonuclear Experimental Reactor)

    SciTech Connect (OSTI)

    Werley, K.A.

    1989-01-01T23:59:59.000Z

    A high-speed (160m/s) beam (0.14 {times} 0.86m) of liquid-lithium droplets passing through the divertor region(s) below (and above) the main plasma has the potential to replace and out-perform conventional'' solid divertor plates in both heat and particle removal. In addition to superior heat-collection properties, the lithium beam would: remove impurities; require low power to circulate the lithium; exhibit low-recycle divertor operation compatible with lower-hybrid current drive, H-mode plasma confinement, and no flow reversal in the edge plasma; be insensitive to plasma shifts; and finally protect solid structures from the plasma thermal energy for those disruptions that deposit energy preferentially into the divertor while simultaneously being rapidly re-established after a major disruption. Scoping calculations identifying the beam configuration and the droplet dynamics, including formation, MHD effects, gravitational effects, thermal response and hydrodynamics, are presented. Limitations and uncertainties are also discussed. 20 refs., 6 figs., 3 tabs.

  20. Electron Screening Effect on Stellar Thermonuclear Fusion

    E-Print Network [OSTI]

    K. -h. Spatschek; M. Bonitz; T. Klinger; U. Ebert; C. Franck; A. V. Keudell; D. Naujoks; M. Dewitz; A. Y. Potekhin; G. Chabrier

    2012-01-01T23:59:59.000Z

    thermonuclear fusions and show that these scenarios do not apply to stellar conditions. c ? 2013 WILEY

  1. Thermonuclear Reflect AB-Reactor

    E-Print Network [OSTI]

    Alexander Bolonkin

    2008-03-26T23:59:59.000Z

    The author offers a new kind of thermonuclear reflect reactor. The remarkable feature of this new reactor is a three net AB reflector, which confines the high temperature plasma. The plasma loses part of its energy when it contacts with the net but this loss can be compensated by an additional permanent plasma heating. When the plasma is rarefied (has a small density), the heat flow to the AB reflector is not large and the temperature in the triple reflector net is lower than 2000 - 3000 K. This offered AB-reactor has significantly less power then the currently contemplated power reactors with magnetic or inertial confinement (hundreds-thousands of kW, not millions of kW). But it is enough for many vehicles and ships and particularly valuable for tunnelers, subs and space apparatus, where air to burn chemical fuel is at a premium or simply not available. The author has made a number of innovations in this reactor, researched its theory, developed methods of computation, made a sample computation of typical project. The main point of preference for the offered reactor is its likely cheapness as a power source. Key words: Micro-thermonuclear reactor, Multi-reflex AB-thermonuclear reactor, Self-magnetic AB-thermonuclear reactor, aerospace thermonuclear engine.

  2. EU to build experimental fusion reactor Associated Press, THE JERUSALEM POST Sep 25, 2006

    E-Print Network [OSTI]

    EU to build experimental fusion reactor Associated Press, THE JERUSALEM POST Sep 25, 2006 European Union nations on Monday endorsed a pact to build an experimental fusion reactor with the aim, China, Japan, South Korea and Russia - also aim to ratify the International Thermonuclear Experimental

  3. President Truman Orders Development of Thermonuclear Weapon ...

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

    Orders Development of Thermonuclear Weapon | National Nuclear Security Administration Facebook Twitter Youtube Flickr RSS People Mission Managing the Stockpile Preventing...

  4. Approaches to modeling thermonuclear flames

    E-Print Network [OSTI]

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

    Turbulence-flame interactions of thermonuclear fusion flames occurring in Type Ia Supernovae were studied by means of incompressible DNS with a highly simplified flame description. The flame is treated as a single diffusive scalar field with a nonlinear source term. It is characterized by its

  5. New Views of Thermonuclear Bursts

    E-Print Network [OSTI]

    Tod Strohmayer; Lars Bildsten

    2003-05-06T23:59:59.000Z

    Since the advent of powerful new X-ray observatories, NASA's Rossi X-ray Timing Explorer (RXTE), the Italian - Dutch BeppoSAX mission, XMM-Newton and Chandra, a number of entirely new phenomena associated with thermonuclear burning on neutron stars have been discovered. These include: (i) the discovery of millisecond (300 - 600 Hz) oscillations during bursts, so called ``burst oscillations'', (ii) a new regime of nuclear burning on neutron stars which manifests itself through the generation of hours long flares about once a decade, now referred to as ``superbursts'',(iii) discoveries of bursts from low accretion rate neutron stars, and (iv) new evidence for discrete spectral features from bursting neutron stars. In this article we review our current understanding of thermonuclear bursts on neutron stars, with a focus on these new phenomena.

  6. Thermonuclear Ignition of Dark Galaxies

    E-Print Network [OSTI]

    J. Marvin Herndon

    2006-04-13T23:59:59.000Z

    Dark matter is thought to be at least an order of magnitude more abundant than luminous matter in the Universe, but there has yet to be an unambiguous identification of a wholly dark, galactic-scale structure. There is, however, increasing evidence that VIRGOHI 21 may be a dark galaxy. If VIRGOHI 21 turns out to be composed of dark stars, having approximately the same mass of stars found in luminous galaxies, it will pose an enigma within the framework of current astrophysical models, but will provide strong support for my concept, published in 1994 in the Proceedings of the Royal Society of London, of the thermonuclear ignition of stars by nuclear fission, and the corollary, non-ignition of stars. The possibility of galactic thermonuclear ignition is discussed from that framework and leads to my suggestion that the distribution of luminous stars in a galaxy may simply be a reflection of the galactic distribution of the heavy elements.

  7. Lower hybrid current drive at densities required for thermonuclear reactors R. Cesario 1), L. Amicucci 2), M. L. Apicella 1), G. Calabr 1), A. Cardinali 1), C. Castaldo 1),

    E-Print Network [OSTI]

    Vlad, Gregorio

    EXW/P7-02 Lower hybrid current drive at densities required for thermonuclear reactors R@frascati.enea.it Abstract. For the progress of the thermonuclear fusion energy research based on the tokamak concept in ITER (International Thermonuclear Experiment Reactor) at relatively high plasma densities also

  8. Experimental Highlights - 2014

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

    weapons as they age or are subjected to the immense pressures and temperatures of a thermonuclear explosion. By providing experimental data to compare to computer models of...

  9. atypical thermonuclear supernovae: Topics by E-print Network

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

    Websites Summary: White dwarf mergers,White dwarf mergers, thermonuclear supernovae,thermonuclear supernovae fusion is ignited. Degenerate, hence runaway. 12;CO white dwarf...

  10. Workshop on Thermonuclear Reaction Rates for Astrophysics Applications

    E-Print Network [OSTI]

    Workshop on Thermonuclear Reaction Rates for Astrophysics Applications 24-25 November 2011, Athensrd and final circular for the Workshop on Thermonuclear Reaction Rates for Astrophysics Applications

  11. Greenpeace International Jun 28, 2005 @ 11:06 am

    E-Print Network [OSTI]

    archive Posted on: Nuclear fusion reactor project in France: an expensive and senseless nuclear stupidity Paris, 28 June 2005 - Greenpeace deplores the agreement by the Representatives of the Parties to the International Thermonuclear Experimental Reactor (ITER) (1) to construct one of the world's largest nuclear

  12. Energy chief tells Jersey: Fusion's back Secretary, at top research lab in Plainsboro, says country resuming international effort

    E-Print Network [OSTI]

    plan to build a $5 billion fusion reactor, called the International Thermonuclear Experimental ReactorEnergy chief tells Jersey: Fusion's back Secretary, at top research lab in Plainsboro, says country States plans to resume participation in an international collaboration to develop fusion energy

  13. On thermonuclear ignition criterion at the National Ignition Facility

    SciTech Connect (OSTI)

    Cheng, Baolian; Kwan, Thomas J. T.; Wang, Yi-Ming; Batha, Steven H. [Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States)

    2014-10-15T23:59:59.000Z

    Sustained thermonuclear fusion at the National Ignition Facility remains elusive. Although recent experiments approached or exceeded the anticipated ignition thresholds, the nuclear performance of the laser-driven capsules was well below predictions in terms of energy and neutron production. Such discrepancies between expectations and reality motivate a reassessment of the physics of ignition. We have developed a predictive analytical model from fundamental physics principles. Based on the model, we obtained a general thermonuclear ignition criterion in terms of the areal density and temperature of the hot fuel. This newly derived ignition threshold and its alternative forms explicitly show the minimum requirements of the hot fuel pressure, mass, areal density, and burn fraction for achieving ignition. Comparison of our criterion with existing theories, simulations, and the experimental data shows that our ignition threshold is more stringent than those in the existing literature and that our results are consistent with the experiments.

  14. Statistical Methods for Thermonuclear Reaction Rates and Nucleosynthesis Simulations

    E-Print Network [OSTI]

    Iliadis, Christian; Coc, Alain; Timmes, F X; Champagne, Art E

    2014-01-01T23:59:59.000Z

    Rigorous statistical methods for estimating thermonuclear reaction rates and nucleosynthesis are becoming increasingly established in nuclear astrophysics. The main challenge being faced is that experimental reaction rates are highly complex quantities derived from a multitude of different measured nuclear parameters (e.g., astrophysical S-factors, resonance energies and strengths, particle and gamma-ray partial widths). We discuss the application of the Monte Carlo method to two distinct, but related, questions. First, given a set of measured nuclear parameters, how can one best estimate the resulting thermonuclear reaction rates and associated uncertainties? Second, given a set of appropriate reaction rates, how can one best estimate the abundances from nucleosynthesis (i.e., reaction network) calculations? The techniques described here provide probability density functions that can be used to derive statistically meaningful reaction rates and final abundances for any desired coverage probability. Examples ...

  15. Thermonuclear burst physics with RXTE

    E-Print Network [OSTI]

    D. K. Galloway; D. Chakrabarty; A. Cumming; E. Kuulkers; L. Bildsten; R. Rothschild

    2004-04-22T23:59:59.000Z

    Recently we have made measurements of thermonuclear burst energetics and recurrence times which are unprecedented in their precision, largely thanks to the sensitivity of the Rossi X-ray Timing Explorer. In the "Clocked Burster", GS 1826-24, hydrogen burns during the burst via the rapid-proton (rp) process, which has received particular attention in recent years through theoretical and modelling studies. The burst energies and the measured variation of alpha (the ratio of persistent to burst flux) with accretion rate strongly suggests solar metallicity in the neutron star atmosphere, although this is not consistent with the corresponding variation of the recurrence time. Possible explanations include extra heating between the bursts, or a change in the fraction of the neutron star over which accretion takes place. I also present results from 4U 1746-37, which exhibits regular burst trains which are interrupted by "out of phase" bursts.

  16. Tidally-induced thermonuclear Supernovae

    E-Print Network [OSTI]

    S. Rosswog; E. Ramirez-Ruiz; W. R. Hix

    2008-11-13T23:59:59.000Z

    We discuss the results of 3D simulations of tidal disruptions of white dwarfs by moderate-mass black holes as they may exist in the cores of globular clusters or dwarf galaxies. Our simulations follow self-consistently the hydrodynamic and nuclear evolution from the initial parabolic orbit over the disruption to the build-up of an accretion disk around the black hole. For strong enough encounters (pericentre distances smaller than about 1/3 of the tidal radius) the tidal compression is reversed by a shock and finally results in a thermonuclear explosion. These explosions are not restricted to progenitor masses close to the Chandrasekhar limit, we find exploding examples throughout the whole white dwarf mass range. There is, however, a restriction on the masses of the involved black holes: black holes more massive than $2\\times 10^5$ M$_\\odot$ swallow a typical 0.6 M$_\\odot$ dwarf before their tidal forces can overwhelm the star's self-gravity. Therefore, this mechanism is characteristic for black holes of moderate masses. The material that remains bound to the black hole settles into an accretion disk and produces an X-ray flare close to the Eddington limit of $L_{\\rm Edd} \\simeq 10^{41} {\\rm erg/s} M_{\\rm bh}/1000 M$_\\odot$), typically lasting for a few months. The combination of a peculiar thermonuclear supernova together with an X-ray flare thus whistle-blows the existence of such moderate-mass black holes. The next generation of wide field space-based instruments should be able to detect such events.

  17. Electron screening effect on stellar thermonuclear fusion

    E-Print Network [OSTI]

    Potekhin, A Y

    2013-01-01T23:59:59.000Z

    We study the impact of plasma correlation effects on nonresonant thermonuclear reactions for various stellar objects, namely in the liquid envelopes of neutron stars, and the interiors of white dwarfs, low-mass stars, and substellar objects. We examine in particular the effect of electron screening on the enhancement of thermonuclear reactions in dense plasmas within and beyond the linear mixing rule approximation as well as the corrections due to quantum effects at high density. In addition, we examine some recent unconventional (Yukawa-potential and "quantum-tail") theoretical results on stellar thermonuclear fusions and show that these scenarios do not apply to stellar conditions.

  18. The physics of antimatter induced fusion and thermonuclear explosions

    E-Print Network [OSTI]

    Andre Gsponer; Jean-pierre Hurni

    triggering large scale thermonuclear explosions is investigated. The number of antiproton annihilations

  19. Workshop on Thermonuclear Reaction Rates for Astrophysics Applications

    E-Print Network [OSTI]

    Workshop on Thermonuclear Reaction Rates for Astrophysics Applications 24-25 November 2011, Athens circular for the Workshop on Thermonuclear Reaction Rates for Astrophysics Applications, to be held of thermonuclear reaction rates. The topics of the workshop, in relation with thermonuclear reaction rates

  20. Thermonuclear Fusion Research Progress and the Way to the Reactor

    SciTech Connect (OSTI)

    Koch, Raymond [Laboratory for Plasma Physics, Royal Military Academy, Association EURATOM - Belgian State, 1000 Brussels (Belgium)

    2006-06-08T23:59:59.000Z

    The paper reviews the progress of fusion research and its prospects for electricity generation. It starts with a reminder of the principles of thermonuclear fusion and a brief discussion of its potential role in the future of the world energy production. The reactions allowing energy production by fusion of nuclei in stars and on earth and the conditions required to sustain them are reviewed. At the high temperatures required for fusion (hundred millions kelvins), matter is completely ionized and has reached what is called its 4th state: the plasma state. The possible means to achieve these extreme temperatures is discussed. The remainder of the paper focuses on the most promising of these approaches, magnetic confinement. The operating principles of the presently most efficient machine of this type -- the tokamak -- is described in some detail. On the road to producing energy with fusion, a number of obstacles have to be overcome. The plasma, a fluid that reacts to electromagnetic forces and carries currents and charges, is a complex medium. Fusion plasma is strongly heated and is therefore a good example of a system far from equilibrium. A wide variety of instabilities can grow in this system and lead to self-organized structures and spontaneous cycles. Turbulence is generated that degrades the confinement and hinders easy achievement of long lasting hot plasmas. Physicists have learned how to quench turbulence, thereby creating sort of insulating bottles inside the plasma itself to circumvent this problem. The recent history of fusion performance is outlined and the prospect of achieving power generation by fusion in a near future is discussed in the light of the development of the 'International Tokamak Experimental Reactor' project ITER.

  1. UV Light Curves of Thermonuclear Supernovae

    E-Print Network [OSTI]

    S. I. Blinnikov; E. I. Sorokina

    2000-03-17T23:59:59.000Z

    Ultraviolet light curves are calculated for several thermonuclear supernova models using a multifrequency radiation hydrodynamic code. It is found that Chandrasekhar-mass models produce very similar light curves both for detonation and deflagration. Sub-Chandrasekhar-mass models essentially differ from ``normal'' Chandrasekhar ones regarding behaviour of their UV fluxes. Differences in absolute brightness and in shape of light curves of thermonuclear supernovae could be detectable up to 300 Mpc with modern UV space telescopes.

  2. White dwarf mergers,White dwarf mergers, thermonuclear supernovae,thermonuclear supernovae,

    E-Print Network [OSTI]

    Hinton, Jim

    White dwarf mergers,White dwarf mergers, thermonuclear supernovae,thermonuclear supernovae fusion is ignited. Degenerate, hence runaway. #12;CO white dwarf accretes, either from companion, or from disk after merger. As it approaches maximum mass, C fusion is ignited. Degenerate, hence runaway. SN Ia

  3. The Development and Experimentation of an International Standard for Very Small Entities

    E-Print Network [OSTI]

    Québec, Université du

    . ISO/IEC JTC 1/SC7 = International Organization for Standardization/ International ElectrotechnicalThe Development and Experimentation of an International Standard for Very Small Entities Involved) ­ Survey of VSEs worldwide (2006) · Phase 3 - Development ­ The Development of International Standards

  4. Antimatter induced fusion and thermonuclear explosions

    E-Print Network [OSTI]

    Gsponer, A; Gsponer, Andre; Hurni, Jean-Pierre

    1987-01-01T23:59:59.000Z

    The feasibility of using antihydrogen for igniting inertial confinement fusion pellets or triggering large scale thermonuclear explosions is investigated. The number of antiproton annihilations required to start a thermonuclear burn wave in either DT or Li_2DT is found to be about 10^{21}/k^2, where k is the compression factor of the fuel to be ignited. In the second part, the technologies for producing antiprotons with high energy accelerator systems and the means for manipulating and storing microgram amounts of antihydrogen are examined. While there seems to be no theoretical obstacles to the production of 10^{18} antiprotons per day (the amount required for triggering one thermonuclear bomb), the construction of such a plant involves several techniques which are between 3 and 4 orders of magnitude away from present day technology.

  5. The Development and Experimentation of an International Standard for Very Small Entities

    E-Print Network [OSTI]

    Québec, Université du

    The Development and Experimentation of an International Standard for Very Small Entities Involved are enterprises, projects or departments having up to 25 people. ISO/IEC JTC 1/SC 7 = International Organization for Standardization/ International Electrotechnical Commission Joint Technical Committee 1/Sub Committee 7. #12

  6. THE POSSIBILITY OF PRODUCING THERMONUCLEAR REACTIONS IN A GASEOUS DISCHARGE*

    E-Print Network [OSTI]

    THE POSSIBILITY OF PRODUCING THERMONUCLEAR REACTIONS IN A GASEOUS DISCHARGE* I.V. Kurchatov of the energy of thermonuclear reactions. Physicists the world over are attracted by the extraordinarily interest- ing and very difficult task of controlling thermonuclear reactiom. Investigations in this field

  7. New AB-Thermonuclear Reactor for Aerospace

    E-Print Network [OSTI]

    Alexander Bolonkin

    2007-06-14T23:59:59.000Z

    There are two main methods of nulcear fusion: inertial confinement fusion (ICF) and magnetic confinement fusion (MCF). Existing thermonuclear reactors are very complex, expensive, large, and heavy. They cannot achieve the Lawson creterion. The author offers an innovation. ICF has on the inside surface of the shell-shaped combustion chamber a covering of small Prism Reflectors (PR) and plasma reflector. These prism reflectors have a noteworthy advantage, in comparison with conventional mirror and especially with conventional shell: they multi-reflect the heat and laser radiation exactly back into collision with the fuel target capsule (pellet). The plasma reflector reflects the Bremsstrahlung radiation. The offered innovation decreases radiation losses, creates significant radiation pressure and increases the reaction time. The Lawson criterion increases by hundreds of times. The size, cost, and weight of a typical installation will decrease by tens of times. The author is researching the efficiency of these innovations. Keywords: Thermonuclear reactor, Multi-reflex AB-thermonuclear reactor, aerospace thermonuclear engine. This work is presented as paper AIAA-2006-7225 to Space-2006 Conference, 19-21 September, 2006, San Jose, CA, USA.

  8. Introduction to Magnetic Thermonuclear Fusion and

    E-Print Network [OSTI]

    Shihadeh, Alan

    Introduction to Magnetic Thermonuclear Fusion and Related Research Projects Ghassan Antar Fusion 2. Research on Turbulence (Theory and Experiment) 3. Research on Disruptions 4. Research on Plasma Facing Components #12;Ghassan Y. ANTAR 3 Fusion Occurs when Two Nuclei Unite to Form One The Energy

  9. Resonances and the thermonuclear reaction rate

    E-Print Network [OSTI]

    M. S. Hussein; M. Ueda; A. J. Sargeant; M. P. Pato

    2003-07-21T23:59:59.000Z

    We present an approximate analytic expression for thermonuclear reaction rate of charged particles when the cross section contains a single narrow or wide resonance described by a Breit-Wigner shape. The resulting expression is uniformly valid as the effective energy and resonance energy coalesce. We use our expressions to calculate the reaction rate for $^{12}$C(p,$\\gamma$)$^{13}$N.

  10. Micro -Thermonuclear AB-Reactors for Aerospace

    E-Print Network [OSTI]

    Alexander Bolonkin

    2007-01-08T23:59:59.000Z

    The author offers several innovations that he first suggested publicly early in 1983 for the AB multi-reflex engine, space propulsion, getting energy from plasma, etc. (see: A. Bolonkin, Non-Rocket Space Launch and Flight, Elsevier, London, 2006, Chapters 12, 3A). It is the micro-thermonuclear AB-Reactors. That is new micro-thermonuclear reactor with very small fuel pellet that uses plasma confinement generated by multi-reflection of laser beam or its own magnetic field. The Lawson criterion increases by hundreds of times. The author also suggests a new method of heating the power-making fuel pellet by outer electric current as well as new direct method of transformation of ion kinetic energy into harvestable electricity. These offered innovations dramatically decrease the size, weight and cost of thermonuclear reactor, installation, propulsion system and electric generator. Non-industrial countries can produce these researches and constructions. Currently, the author is researching the efficiency of these innovations for two types of the micro-thermonuclear reactors: multi-reflection reactor (ICF) and self-magnetic reactor (MCF).

  11. Neutron capture of 26Mg at thermonuclear energies

    E-Print Network [OSTI]

    P. Mohr; H. Beer; H. Oberhummer; G. Staudt

    1998-05-20T23:59:59.000Z

    The neutron capture cross section of 26Mg was measured relative to the known gold cross section at thermonuclear energies using the fast cyclic activation technique. The experiment was performed at the 3.75 MV Van-de-Graaff accelerator, Forschungszentrum Karlsruhe. The experimental capture cross section is the sum of resonant and direct contributions. For the resonance at E(n,lab) = 220 keV our new results are in disagreement with the data from Weigmann et al. An improved Maxwellian averaged capture cross section is derived from the new experimental data taking into account s- and p-wave capture and resonant contributions. The properties of so-called potential resonances which influence the p-wave neutron capture of 26}Mg are discussed in detail.

  12. Theoretical and experimental study of nonlinear internal gravity wave beams

    E-Print Network [OSTI]

    Tabaei Befrouei, Ali, 1974-

    2005-01-01T23:59:59.000Z

    Continuously stratified fluids, like the atmosphere and the oceans, support internal gravity waves due to the effect of buoyancy. This type of wave motion is anisotropic since gravity provides a preferred direction. As a ...

  13. Statistical Methods for Thermonuclear Reaction Rates and Nucleosynthesis Simulations

    E-Print Network [OSTI]

    Christian Iliadis; Richard Longland; Alain Coc; F. X. Timmes; Art E. Champagne

    2014-09-19T23:59:59.000Z

    Rigorous statistical methods for estimating thermonuclear reaction rates and nucleosynthesis are becoming increasingly established in nuclear astrophysics. The main challenge being faced is that experimental reaction rates are highly complex quantities derived from a multitude of different measured nuclear parameters (e.g., astrophysical S-factors, resonance energies and strengths, particle and gamma-ray partial widths). We discuss the application of the Monte Carlo method to two distinct, but related, questions. First, given a set of measured nuclear parameters, how can one best estimate the resulting thermonuclear reaction rates and associated uncertainties? Second, given a set of appropriate reaction rates, how can one best estimate the abundances from nucleosynthesis (i.e., reaction network) calculations? The techniques described here provide probability density functions that can be used to derive statistically meaningful reaction rates and final abundances for any desired coverage probability. Examples are given for applications to s-process neutron sources, core-collapse supernovae, classical novae, and big bang nucleosynthesis.

  14. Merging White Dwarfs and Thermonuclear Supernovae

    E-Print Network [OSTI]

    van Kerkwijk, Marten H

    2012-01-01T23:59:59.000Z

    Thermonuclear supernovae result when interaction with a companion reignites nuclear fusion in a carbon-oxygen white dwarf, causing a thermonuclear runaway, a catastrophic gain in pressure, and the disintegration of the whole white dwarf. It is usually thought that fusion is reignited in near-pycnonuclear conditions when the white dwarf approaches the Chandrasekhar mass. I briefly describe two long-standing problems faced by this scenario, and our suggestion that these supernovae instead result from mergers of carbon-oxygen white dwarfs, including those that produce sub-Chandrasekhar mass remnants. I then turn to possible observational tests, in particular those that test the absence or presence of electron captures during the burning.

  15. Experimental assessment of the internal flow behavior of supercritical carbon dioxide

    E-Print Network [OSTI]

    Yang, David, S.M. Massachusetts Institute of Technology

    2014-01-01T23:59:59.000Z

    This thesis presents an experimental assessment of the internal flow behavior of supercritical carbon dioxide. The investigation focused mainly on assessing condensation onset during rapid expansion of CO? into the two-phase ...

  16. Solar Models and NACRE thermonuclear reaction rates

    E-Print Network [OSTI]

    P. Morel; B. Pichon; J. Provost; G. Berthomieu

    1999-07-27T23:59:59.000Z

    Using the most recent updated physics, calibrated solar models have been computed with the new thermonuclear reaction rates of NACRE, the recently available European compilation. Comparisons with models computed with the reaction rates of Caughlan & Fowler (\\cite{cf88}) and of Adelberger et al. (\\cite{a98}) are made for global structure, expected neutrinos fluxes, chemical composition and sound speed profiles, helioseismological properties of p-modes and g-modes.

  17. Thermonuclear processes of the Universe

    E-Print Network [OSTI]

    Sergey B. Dubovichenko

    2011-08-12T23:59:59.000Z

    The book considers some theoretical questions of nuclear astro-physics thermal energies and light atomic nuclei. For the analysis of re-actions is used potential two cluster model of light nuclei with classifica-tion of states by orbital schemes. On its basis photonuclear processes in p2H, p3H, p6Li, p7Li, p9Be and p12C, and also 2H4He, 3H4He, 3He4He and 4He12C channels are considered and astrophysical S - factors corre-sponding to them are calculated. It is shown, that used methods allow to describe well available experimental data in the field of astrophysical energies. This Book is written in Russian, but will perhaps present certain interest.

  18. Stars as thermonuclear reactors: their fuels and ashes

    E-Print Network [OSTI]

    A. Ray

    2004-05-28T23:59:59.000Z

    Atomic nuclei are transformed into each other in the cosmos by nuclear reactions inside stars: -- the process of nucleosynthesis. The basic concepts of determining nuclear reaction rates inside stars and how they manage to burn their fuel so slowly most of the time are discussed. Thermonuclear reactions involving protons in the hydrostatic burning of hydrogen in stars are discussed first. This is followed by triple alpha reactions in the helium burning stage and the issues of survival of carbon and oxygen in red giant stars connected with nuclear structure of oxygen and neon. Advanced stages of nuclear burning in quiescent reactions involving carbon, neon, oxygen and silicon are discussed. The role of neutron induced reactions in nucleosynthesis beyond iron is discussed briefly, as also the experimental detection of neutrinos from SN 1987A which confirmed broadly the ideas concerning gravitational collapse leading to a supernova.

  19. EXPERIMENTAL OBSERVATION OF INTERNAL AND EXTERNAL KINKS IN THE

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOEThe Bonneville Power AdministrationField Campaign:INEA :Work4/11 ENVIROISSUESEVALUATINGG7.0 AttachmentINTERNAL

  20. Convective heating analysis of an IFE target in a high temperature, low Reynolds number xenon environment

    E-Print Network [OSTI]

    Holdener, Dain Steffen

    2011-01-01T23:59:59.000Z

    conditions required for thermonuclear burn lies on the edgeThe International Thermonuclear Experimental Reactor (ITER)is successful in achieving thermonuclear burn. While NIF is

  1. Probing thermonuclear supernova explosions with neutrinos

    E-Print Network [OSTI]

    A. Odrzywolek; T. Plewa

    2011-03-27T23:59:59.000Z

    Aims: We present neutrino light curves and energy spectra for two representative type Ia supernova explosion models: a pure deflagration and a delayed detonation. Methods: We calculate the neutrino flux from $\\beta$ processes using nuclear statistical equilibrium abundances convoluted with approximate neutrino spectra of the individual nuclei and the thermal neutrino spectrum (pair+plasma). Results: Although the two considered thermonuclear supernova explosion scenarios are expected to produce almost identical electromagnetic output, their neutrino signatures appear vastly different, which allow an unambiguous identification of the explosion mechanism: a pure deflagration produces a single peak in the neutrino light curve, while the addition of the second maximum characterizes a delayed-detonation. We identified the following main contributors to the neutrino signal: (1) weak electron neutrino emission from electron captures (in particular on the protons Co55 and Ni56) and numerous beta-active nuclei produced by the thermonuclear flame and/or detonation front, (2) electron antineutrinos from positron captures on neutrons, and (3) the thermal emission from pair annihilation. We estimate that a pure deflagration supernova explosion at a distance of 1 kpc would trigger about 14 events in the future 50 kt liquid scintillator detector and some 19 events in a 0.5 Mt water Cherenkov-type detector. Conclusions: While in contrast to core-collapse supernovae neutrinos carry only a very small fraction of the energy produced in the thermonuclear supernova explosion, the SN Ia neutrino signal provides information that allows us to unambiguously distinguish between different possible explosion scenarios. These studies will become feasible with the next generation of proposed neutrino observatories.

  2. The Fractional Kinetic Equation and Thermonuclear Functions

    E-Print Network [OSTI]

    H. J. Haubold; A. M. Mathai

    2000-01-16T23:59:59.000Z

    The paper discusses the solution of a simple kinetic equation of the type used for the computation of the change of the chemical composition in stars like the Sun. Starting from the standard form of the kinetic equation it is generalized to a fractional kinetic equation and its solutions in terms of H-functions are obtained. The role of thermonuclear functions, which are also represented in terms of G- and H-functions, in such a fractional kinetic equation is emphasized. Results contained in this paper are related to recent investigations of possible astrophysical solutions of the solar neutrino problem.

  3. New material for thermonuclear fusion reactors | EurekAlert! Science News

    E-Print Network [OSTI]

    ... Jan-2012 New material for thermonuclear fusion reactors ... to develop new materials for thermonuclear fusion reactors. Their research focuses ... to develop new materials for thermonuclear fusion reactors. Their research focuses ...

  4. NASA's RXTE captures thermonuclear behavior of unique neutron star | EurekAlert! Science ..

    E-Print Network [OSTI]

    ... 2012 NASA's RXTE captures thermonuclear behavior of unique neutron star ... powered by a barrage of thermonuclear explosions on the star's ... minutes and caused by a thermonuclear explosion on the neutron star ...

  5. Oscillations During Thermonuclear X-ray Bursts

    E-Print Network [OSTI]

    Tod E. Strohmayer

    2001-01-12T23:59:59.000Z

    High amplitude, nearly coherent X-ray brightness oscillations during thermonuclear X-ray bursts were discovered with the Rossi X-ray Timing Explorer (RXTE) in early 1996. Spectral and timing evidence strongly supports the conclusion that these oscillations are caused by rotational modulation of the burst emission and that they reveal the spin frequency of neutron stars in low mass X-ray binaries, a long sought goal of X-ray astronomy. Studies carried out over the past year have led to the discovery of burst oscillations in four new sources, bringing to ten the number with confirmed burst oscillations. I review the status of our knowledge of these oscillations and indicate how they can be used to probe the physics of neutron stars. For a few burst oscillation sources it has been proposed that the strongest and most ubiquitous frequency is actually the first overtone of the spin frequency and hence that two nearly antipodal hot spots are present on the neutron star. This inference has important implications for both the physics of thermonuclear burning as well as the mass - radius relation for neutron stars, so its confirmation is crucial. I discuss recent attempts to confirm this hypothesis for 4U 1636-53, the source for which a signal at the putative fundamental (290 Hz) has been claimed.

  6. The physics of antimatter induced fusion and thermonuclear explosions

    E-Print Network [OSTI]

    Andre Gsponer; Jean-pierre Hurni

    The feasibility of using antihydrogen for igniting inertial confinement fusion pellets or triggering large scale thermonuclear explosions is investigated. The number of antiproton annihilations required to start a thermonuclear burn wave in either DT or Li2DT is found to be about 10 21 /k 2, where

  7. Thermonuclear Fusion Energy : Assessment and Next Step Ren Pellat

    E-Print Network [OSTI]

    Thermonuclear Fusion Energy : Assessment and Next Step René Pellat High Commissioner at the French 2000, Rome Abstract Fifty years of thermonuclear fusion work with no insurmountable road blocks have allowed to continuously progress towards the fusion reactor which stays a physics and technology ambitious

  8. Simplest AB-Thermonuclear Space Propulsion and Electric Generator

    E-Print Network [OSTI]

    Alexander Bolonkin

    2007-01-19T23:59:59.000Z

    The author applies, develops and researches mini-sized Micro- AB Thermonuclear Reactors for space propulsion and space power systems. These small engines directly convert the high speed charged particles produced in the thermonuclear reactor into vehicle thrust or vehicle electricity with maximum efficiency. The simplest AB-thermonuclear propulsion offered allows spaceships to reach speeds of 20,000 50,000 km/s (1/6 of light speed) for fuel ratio 0.1 and produces a huge amount of useful electric energy. Offered propulsion system permits flight to any planet of our Solar system in short time and to the nearest non-Sun stars by E-being or intellectual robots during a single human life period. Key words: AB-propulsion, thermonuclear propulsion, space propulsion, thermonuclear power system.

  9. The physics of antimatter induced fusion and thermonuclear explosions

    E-Print Network [OSTI]

    Gsponer, A; Gsponer, Andre; Hurni, Jean-Pierre

    1987-01-01T23:59:59.000Z

    The possibility of using antihydrogen for igniting inertial confinement fusion pellets or triggering large scale thermonuclear explosions is investigated. The number of antiproton annihilations required to start a thermonuclear burn wave in either D or Li_2DT is found to be about 10^{21}/k^2, where k is the compression factor of the fuel to be ignited. We conclude that the financial and energy investments needed to produce such amounts of antiprotons would confine applications of antimatter triggered thermonuclear devices to the military domain.

  10. Numerical simulations of welds of thick steel pieces of interest for the thermonuclear fusion ITER machine

    E-Print Network [OSTI]

    Carmignani, B

    2005-01-01T23:59:59.000Z

    Numerical simulations of welds of thick steel pieces of interest for the thermonuclear fusion ITER machine

  11. explosion: Role of hydrogen thermonuclear explosion in support of cometary hypothesis

    E-Print Network [OSTI]

    Y. E. Kim

    2008-01-01T23:59:59.000Z

    deuteron fusion rates and that a thermonuclear explosion may compete with a thermo-chemical explosion

  12. EXTENSION OF THERMONUCLEAR FUNCTIONS THROUGH THE PATHWAY MODEL INCLUDING MAXWELL-BOLTZMANN AND

    E-Print Network [OSTI]

    H. J. Haubold

    of respective thermonuclear functions is being conducted with the help of statistical techniques. The

  13. Recent Steps Towards a Controlled Thermonuclear Fusion Reactor with Results from the JET Tokamak Device

    E-Print Network [OSTI]

    Recent Steps Towards a Controlled Thermonuclear Fusion Reactor with Results from the JET Tokamak Device

  14. Measurement of the Fractional Thermonuclear Neutron Yield during Deuterium Neutral-Beam Injection into Deuterium Plasmas

    E-Print Network [OSTI]

    Measurement of the Fractional Thermonuclear Neutron Yield during Deuterium Neutral-Beam Injection into Deuterium Plasmas

  15. Thermonuclear 42Ti(p,gamma)43V rate in type I X-ray bursts

    E-Print Network [OSTI]

    He, J J; Brown, B A; Rauscher, T; Hou, S Q; Zhang, Y H; Zhou, X H; Xu, H S

    2014-01-01T23:59:59.000Z

    The thermonuclear rate of the $^{42}$Ti($p$,$\\gamma$)$^{43}$V reaction has been reevaluated based on a recent precise proton separation energy measurement of $S_p$($^{43}$V)=83$\\pm$43 keV. The astrophysical impact of our new rates has been investigated through one-zone postprocessing type I x-ray burst calculations. It shows that the new experimental value of $S_p$ significantly affects the yields of species between A$\\approx$40--45. As well, the precision of the recent experimental $S_p$ value constrains these yields to better than a factor of three.

  16. Thermonuclear Reaction Rate of 23Mg(p,gamma)24$Al

    E-Print Network [OSTI]

    H. Herndl; M. Fantini; C. Iliades; P. M. Endt; H. Oberhummer

    1998-06-05T23:59:59.000Z

    Updated stellar rates for the reaction 23Mg(p,gamma)24Al are calculated by using all available experimental information on 24Al excitation energies. Proton and gamma-ray partial widths for astrophysically important resonances are derived from shell model calculations. Correspondences of experimentally observed 24Al levels with shell model states are based on application of the isobaric multiplet mass equation. Our new rates suggest that the 23Mg(p,gamma)24Al reaction influences the nucleosynthesis in the mass A>20 region during thermonuclear runaways on massive white dwarfs.

  17. Thermonuclear 42Ti(p,gamma)43V rate in type I X-ray bursts

    E-Print Network [OSTI]

    J. J. He; A. Parikh; B. A. Brown; T. Rauscher; S. Q. Hou; Y. H. Zhang; X. H. Zhou; H. S. Xu

    2014-03-10T23:59:59.000Z

    The thermonuclear rate of the $^{42}$Ti($p$,$\\gamma$)$^{43}$V reaction has been reevaluated based on a recent precise proton separation energy measurement of $S_p$($^{43}$V)=83$\\pm$43 keV. The astrophysical impact of our new rates has been investigated through one-zone postprocessing type I x-ray burst calculations. It shows that the new experimental value of $S_p$ significantly affects the yields of species between A$\\approx$40--45. As well, the precision of the recent experimental $S_p$ value constrains these yields to better than a factor of three.

  18. Modeling Combustion in Current Candidate Scenarios for Thermonuclear...

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

    Combustion in Current Candidate Scenarios for Thermonuclear Supernovae Mar 26 2015 03:00 PM - 04:00 PM Dean M. Townsley, The University of Alabama, Tuscaloosa Physics Division...

  19. Numerical and experimental investigation of melting with internal heat generation within cylindrical enclosures

    SciTech Connect (OSTI)

    Amber Shrivastava; Brian Williams; Ali S. Siahpush; Bruce Savage; John Crepeau

    2014-06-01T23:59:59.000Z

    There have been significant efforts by the heat transfer community to investigate the melting phenomenon of materials. These efforts have included the analytical development of equations to represent melting, numerical development of computer codes to assist in modeling the phenomena, and collection of experimental data. The understanding of the melting phenomenon has application in several areas of interest, for example, the melting of a Phase Change Material (PCM) used as a thermal storage medium as well as the melting of the fuel bundle in a nuclear power plant during an accident scenario. The objective of this research is two-fold. First a numerical investigation, using computational fluid dynamics (CFD), of melting with internal heat generation for a vertical cylindrical geometry is presented. Second, to the best of authors knowledge, there are very limited number of engineering experimental results available for the case of melting with Internal Heat Generation (IHG). An experiment was performed to produce such data using resistive, or Joule, heating as the IHG mechanism. The numerical results are compared against the experimental results and showed favorable correlation. Uncertainties in the numerical and experimental analysis are discussed. Based on the numerical and experimental analysis, recommendations are made for future work.

  20. DEPARTMENT OF ENERGY Since 2001, the Administration

    E-Print Network [OSTI]

    Gen, the Carbon Sequestration Leadership Forum, and the International Thermonuclear Experimental Reactor fusion to the International Thermonuclear Experimental Reactor fusion energy project. Accelerating Breakthroughs

  1. IAEA-CN-SO/F-I-4 ITER: CONCEPT DEFINITION*

    E-Print Network [OSTI]

    way. 1. INTRODUCTION The activity of the International Thermonuclear Experimental Reactor (ITER. * The activity of the International Thermonuclear Experimental Reactor (ITER) is conducted under the auspices

  2. Senate Appropriations Committee Report FY04 Energy and Water Development Act

    E-Print Network [OSTI]

    as a viable energy source. International Thermonuclear Experimental Reactor - The Committee recommendation negotiations aimed at building the International Thermonuclear Experimental Reactor (ITER), a burning plasma

  3. If a dispute with the United States,

    E-Print Network [OSTI]

    proposed by France for the 10-billion-euro (12-billion-dollar) International Thermonuclear Experimental Research Minister Francois D Aubert International Iter Framework International Thermonuclear Site

  4. Thermonuclear Burning on Rapidly Accreting Neutron Stars

    E-Print Network [OSTI]

    Lars Bildsten

    1997-09-10T23:59:59.000Z

    Neutron stars in mass-transferring binaries are accreting the hydrogen and helium rich matter from the surfaces of their companions. This article simply explains the physics associated with how that material eventually fuses to form heavier nuclei and the observations of the time dependent phenomena (such as Type I X-ray bursts) associated with the thermally unstable thermonuclear reactions. We explain how the outcome depends on the composition of the accreting matter, the accretion rate and the mass, radius and thermal state of the neutron star. We also introduce many new analytic relations that are convenient for comparisons to both observations and computational results. After explaining nuclear burning for spherically symmetric accretion onto neutron stars, we discuss the possibility of asymmetric burning. In particular, we discuss some of the mysteries from EXOSAT observations of Type I X-Ray bursts and how the solution to these puzzles may lie in considering the lateral propagation of nuclear burning fronts around the star. Fully understanding this problem requires knowledge of parameters previously neglected such as the distribution of fresh fuel on the star, the magnetic field strength, and the stellar rotation. Recent RXTE observations of bursters may finally tell us some of these parameters.

  5. Thermonuclear supernova simulations with stochastic ignition

    E-Print Network [OSTI]

    W. Schmidt; J. C. Niemeyer

    2005-10-14T23:59:59.000Z

    We apply an ad hoc model for dynamical ignition in three-dimensional numerical simulations of thermonuclear supernovae assuming pure deflagrations. The model makes use of the statistical description of temperature fluctuations in the pre-supernova core proposed by Wunsch & Woosley (2004). Randomness in time is implemented by means of a Poisson process. We are able to vary the explosion energy and nucleosynthesis depending on the free parameter of the model which controls the rapidity of the ignition process. However, beyond a certain threshold, the strength of the explosion saturates and the outcome appears to be robust with respect to number of ignitions. In the most energetic explosions, we find about 0.75 solar masses of iron group elements. Other than in simulations with simultaneous multi-spot ignition, the amount of unburned carbon and oxygen at radial velocities of a few 1000 km/s tends to be reduced for an ever increasing number of ignition events and, accordingly, more pronounced layering results.

  6. Iran cannot have claimed to be building a thermonuclear reactor -To build a thermonuclear reactor by its own efforts is a task absolutely beyond Iran's

    E-Print Network [OSTI]

    Iran cannot have claimed to be building a thermonuclear reactor - expert To build a thermonuclear at the Institute of Nuclear Fusion of the Russian Research Center Kurchatov Institute, said: "Our specialists misunderstood." Work to create a thermonuclear reactor has been pursued in all leading countries for several

  7. Thermonuclear reaction rate of $^{18}$Ne($?$,$p$)$^{21}$Na from Monte-Carlo calculations

    E-Print Network [OSTI]

    P. Mohr; R. Longland; C. Iliadis

    2014-12-14T23:59:59.000Z

    The $^{18}$Ne($\\alpha$,$p$)$^{21}$Na reaction impacts the break-out from the hot CNO-cycles to the $rp$-process in type I X-ray bursts. We present a revised thermonuclear reaction rate, which is based on the latest experimental data. The new rate is derived from Monte-Carlo calculations, taking into account the uncertainties of all nuclear physics input quantities. In addition, we present the reaction rate uncertainty and probability density versus temperature. Our results are also consistent with estimates obtained using different indirect approaches.

  8. Thermonuclear reaction rate of $^{18}$Ne($\\alpha$,$p$)$^{21}$Na from Monte-Carlo calculations

    E-Print Network [OSTI]

    Mohr, P; Iliadis, C

    2014-01-01T23:59:59.000Z

    The $^{18}$Ne($\\alpha$,$p$)$^{21}$Na reaction impacts the break-out from the hot CNO-cycles to the $rp$-process in type I X-ray bursts. We present a revised thermonuclear reaction rate, which is based on the latest experimental data. The new rate is derived from Monte-Carlo calculations, taking into account the uncertainties of all nuclear physics input quantities. In addition, we present the reaction rate uncertainty and probability density versus temperature. Our results are also consistent with estimates obtained using different indirect approaches.

  9. Generation of uniform plasmas by crossed internal oscillating current sheets: Key concepts and experimental verification

    SciTech Connect (OSTI)

    Tsakadze, E.L.; Ostrikov, K.; Tsakadze, Z.L.; Xu, S. [Plasma Sources and Applications Center, NIE, Nanyang Technological University, 1 Nanyang Walk, 637616 Singapore and Optics and Plasma Research Department, Risoe National Laboratory, P.O. Box 49, DK-4000 Roskilde (Denmark); School of Physics, The University of Sydney, New South Wales 2006 (Australia); Plasma Sources and Applications Center, NIE, Nanyang Technological University, 1 Nanyang Walk, 637616 Singapore (Singapore)

    2005-01-01T23:59:59.000Z

    The results of comprehensive experimental studies of the operation, stability, and plasma parameters of the low-frequency (0.46 MHz) inductively coupled plasmas sustained by the internal oscillating rf current are reported. The rf plasma is generated by using a custom-designed configuration of the internal rf coil that comprises two perpendicular sets of eight currents in each direction. Various diagnostic tools, such as magnetic probes, optical emission spectroscopy, and an rf-compensated Langmuir probe were used to investigate the electromagnetic, optical, and global properties of the argon plasma in wide ranges of the applied rf power and gas feedstock pressure. It is found that the uniformity of the electromagnetic field inside the plasma reactor is improved as compared to the conventional sources of inductively coupled plasmas with the external flat coil configuration. A reasonable agreement between the experimental data and computed electromagnetic field topography inside the chamber is reported. The Langmuir probe measurements reveal that the spatial profiles of the electron density, the effective electron temperature, plasma potential, and electron energy distribution/probability functions feature a high degree of the radial and axial uniformity and a weak azimuthal dependence, which is consistent with the earlier theoretical predictions. As the input rf power increases, the azimuthal dependence of the global plasma parameters vanishes. The obtained results demonstrate that by introducing the internal oscillated rf currents one can noticeably improve the uniformity of electromagnetic field topography, rf power deposition, and the plasma density in the reactor.

  10. Measurement of neutron capture on $^{48}$Ca at thermal and thermonuclear energies

    E-Print Network [OSTI]

    H. Beer; C. Coceva; P. V. Sedyshev; Yu. P. Popov; H. Herndl; R. Hofinger; P. Mohr; H. Oberhummer

    1996-08-07T23:59:59.000Z

    At the Karlsruhe pulsed 3.75\\,MV Van de Graaff accelerator the thermonuclear $^{48}$Ca(n,$\\gamma$)$^{49}$Ca(8.72\\,min) cross section was measured by the fast cyclic activation technique via the 3084.5\\,keV $\\gamma$-ray line of the $^{49}$Ca-decay. Samples of CaCO$_3$ enriched in $^{48}$Ca by 77.87\\,\\% were irradiated between two gold foils which served as capture standards. The capture cross-section was measured at the neutron energies 25, 151, 176, and 218\\,keV, respectively. Additionally, the thermal capture cross-section was measured at the reactor BR1 in Mol, Belgium, via the prompt and decay $\\gamma$-ray lines using the same target material. The $^{48}$Ca(n,$\\gamma$)$^{49}$Ca cross-section in the thermonuclear and thermal energy range has been calculated using the direct-capture model combined with folding potentials. The potential strengths are adjusted to the scattering length and the binding energies of the final states in $^{49}$Ca. The small coherent elastic cross section of $^{48}$Ca+n is explained through the nuclear Ramsauer effect. Spectroscopic factors of $^{49}$Ca have been extracted from the thermal capture cross-section with better accuracy than from a recent (d,p) experiment. Within the uncertainties both results are in agreement. The non-resonant thermal and thermonuclear experimental data for this reaction can be reproduced using the direct-capture model. A possible interference with a resonant contribution is discussed. The neutron spectroscopic factors of $^{49}$Ca determined from shell-model calculations are compared with the values extracted from the experimental cross sections for $^{48}$Ca(d,p)$^{49}$Ca and $^{48}$Ca(n,$\\gamma$)$^{49}$Ca.

  11. Thermonuclear Fusion with the Sheared Flow Stabilized Z-Pinch

    E-Print Network [OSTI]

    Winterberg, F

    2008-01-01T23:59:59.000Z

    Two basic approaches to producing thermonuclear fusion with a sheared flow stabilized z-pinch are considered. One consists of heating the entire length of the z-pinch column to the required temperatures. The other basic approach considered here involves the concept of fast ignition. A localized "hot-spot" is produced under the proper conditions to ignite a thermonuclear burn wave in the z-pinch plasma. Here we demonstrate that sheared flow stabilization is more efficient in the fast-ignition method with isentropic compression then in a z-pinch where the entire plasma column is heated.

  12. Thermonuclear Supernovae: Simulations of the Deflagration Stage and Their Implications

    E-Print Network [OSTI]

    V. N. Gamezo; A. M. Khokhlov; E. S. Oran; A. Y. Chtchelkanova; R. O. Rosenberg

    2002-12-03T23:59:59.000Z

    Large-scale three-dimensional numerical simulations of the deflagration stage of a thermonuclear supernova explosion show the formation and evolution of a highly convoluted turbulent flame in a gravitational field of an expanding carbon-oxygen white dwarf. The flame dynamics is dominated by the gravity-induced Rayleigh-Taylor instability that controls the burning rate. The thermonuclear deflagration releases enough energy to produce a healthy explosion. The turbulent flame, however, leaves large amounts of unburnt and partially burnt material near the star center, whereas observations imply these materials only in outer layers. This disagreement could be resolved if the deflagration triggers a detonation.

  13. Thermonuclear explosions of Chandrasekhar-mass C+O white dwarfs

    E-Print Network [OSTI]

    M. Reinecke; W. Hillebrandt

    1998-01-01T23:59:59.000Z

    thermonuclear burning, by means of a new two-dimensional numerical code. Since in the interior of such a massive

  14. Thermonuclear Supernovae: Simulations of the Deflagration Stage and Their Implications

    E-Print Network [OSTI]

    V. N. Gamezo; A. M. Khokhlov; E. S. Oran; A. Y. Chtchelkanova; R. O. Rosenberg

    2003-01-01T23:59:59.000Z

    Large-scale three-dimensional numerical simulations of the deflagration stage of a thermonuclear supernova explosion show the formation and evolution of a highly convoluted turbulent flame in a gravitational field of an expanding carbon-oxygen white dwarf. The flame dynamics is dominated by the

  15. The LOFT perspective on neutron star thermonuclear bursts

    E-Print Network [OSTI]

    Zand, J J M in 't; Ballantyne, D R; Bhattacharyya, S; Brown, E F; Cavecchi, Y; Chakrabarty, D; Chenevez, J; Cumming, A; Degenaar, N; Falanga, M; Galloway, D K; Heger, A; José, J; Keek, L; Linares, M; Mahmoodifar, S; Malone, C M; Méndez, M; Miller, M C; Paerels, F B S; Poutanen, J; Rózanska, A; Schatz, H; Serino, M; Strohmayer, T E; Suleimanov, V F; Thielemann, F -K; Watts, A L; Weinberg, N N; Woosley, S E; Yu, W; Zhang, S; Zingale, M

    2015-01-01T23:59:59.000Z

    This is a White Paper in support of the mission concept of the Large Observatory for X-ray Timing (LOFT), proposed as a medium-sized ESA mission. We discuss the potential of LOFT for the study of thermonuclear X-ray bursts on accreting neutron stars. For a summary, we refer to the paper.

  16. Millisecond oscillations during thermonuclear X-ray bursts

    E-Print Network [OSTI]

    Muno, Michael Patrick, 1975-

    2002-01-01T23:59:59.000Z

    I analyze 68 oscillation trains detected in a search of 159 thermonuclear bursts from eight neutron star X-ray binaries observed with the Rossi X-ray Timing Explorer. I use all data that were public as of September 2001. ...

  17. Japan considers conceding ITER site to France TOKYO, May 4, Kyodo -(EDS: UPDATING WITH MACHIMURA MEETING WITH BARNIER IN

    E-Print Network [OSTI]

    the planned International Thermonuclear Experimental Reactor in Rokkasho, Aomori Prefecture, and bowing out plant is an experimental facility of thermonuclear fusion, at which nuclear fusion reactions that occur

  18. The Effects of Thermonuclear Reaction Rate Variations on Nova Nucleosynthesis: A Sensitivity Study

    E-Print Network [OSTI]

    Christian Iliadis; Art Champagne; Jordi Jose; Sumner Starrfield; Paul Tupper

    2002-06-03T23:59:59.000Z

    We investigate the effects of thermonuclear reaction rate uncertainties on nova nucleosynthesis. One-zone nucleosynthesis calculations have been performed by adopting temperature-density-time profiles of the hottest hydrogen-burning zone (i.e., the region in which most of the nucleosynthesis takes place). We obtain our profiles from 7 different, recently published, hydrodynamic nova simulations covering peak temperatures in the range from Tpeak=0.145-0.418 GK. For each of these profiles, we individually varied the rates of 175 reactions within their associated errors and analyzed the resulting abundance changes of 142 isotopes in the mass range below A=40. In total, we performed 7350 nuclear reaction network calculations. We use the most recent thermonuclear reaction rate evaluations for the mass ranges A=1-20 and A=20-40. For the theoretical astrophysicist, our results indicate the extent to which nova nucleosynthesis calculations depend on presently uncertain nuclear physics input, while for the experimental nuclear physicist our results represent at least a qualitative guide for future measurements at stable and radioactive ion beam facilities. We find that present reaction rate estimates are reliable for predictions of Li, Be, C and N abundances in nova nucleosynthesis. However, rate uncertainties of several reactions have to be reduced significantly in order to predict more reliable O, F, Ne, Na, Mg, Al, Si, S, Cl and Ar abundances. Results are presented in tabular form for each adopted nova simulation.

  19. Strong plasma screening in thermonuclear reactions: Electron drop model

    E-Print Network [OSTI]

    Kravchuk, P A

    2014-01-01T23:59:59.000Z

    We analyze enhancement of thermonuclear fusion reactions due to strong plasma screening in dense matter using a simple electron drop model. The model assumes fusion in a potential that is screened by an effective electron cloud around colliding nuclei (extended Salpeter ion-sphere model). We calculate the mean field screened Coulomb potentials for atomic nuclei with equal and nonequal charges, appropriate astrophysical S factors, and enhancement factors of reaction rates. As a byproduct, we study analytic behavior of the screening potential at small separations between the reactants. In this model, astrophysical S factors depend not only on nuclear physics but on plasma screening as well. The enhancement factors are in good agreement with calculations by other methods. This allows us to formulate the combined, pure analytic model of strong plasma screening in thermonuclear reactions. The results can be useful for simulating nuclear burning in white dwarfs and neutron stars.

  20. Strong plasma screening in thermonuclear reactions: Electron drop model

    E-Print Network [OSTI]

    P. A. Kravchuk; D. G. Yakovlev

    2014-01-11T23:59:59.000Z

    We analyze enhancement of thermonuclear fusion reactions due to strong plasma screening in dense matter using a simple electron drop model. The model assumes fusion in a potential that is screened by an effective electron cloud around colliding nuclei (extended Salpeter ion-sphere model). We calculate the mean field screened Coulomb potentials for atomic nuclei with equal and nonequal charges, appropriate astrophysical S factors, and enhancement factors of reaction rates. As a byproduct, we study analytic behavior of the screening potential at small separations between the reactants. In this model, astrophysical S factors depend not only on nuclear physics but on plasma screening as well. The enhancement factors are in good agreement with calculations by other methods. This allows us to formulate the combined, pure analytic model of strong plasma screening in thermonuclear reactions. The results can be useful for simulating nuclear burning in white dwarfs and neutron stars.

  1. Method of achieving the controlled release of thermonuclear energy

    DOE Patents [OSTI]

    Brueckner, Keith A. (Ann Arbor, MI)

    1986-01-01T23:59:59.000Z

    A method of achieving the controlled release of thermonuclear energy by illuminating a minute, solid density, hollow shell of a mixture of material such as deuterium and tritium with a high intensity, uniformly converging laser wave to effect an extremely rapid build-up of energy in inwardly traveling shock waves to implode the shell creating thermonuclear conditions causing a reaction of deuterons and tritons and a resultant high energy thermonuclear burn. Utilizing the resulting energy as a thermal source and to breed tritium or plutonium. The invention also contemplates a laser source wherein the flux level is increased with time to reduce the initial shock heating of fuel and provide maximum compression after implosion; and, in addition, computations and an equation are provided to enable the selection of a design having a high degree of stability and a dependable fusion performance by establishing a proper relationship between the laser energy input and the size and character of the selected material for the fusion capsule.

  2. Relativistic outflow from two thermonuclear shell flashes on neutron stars

    E-Print Network [OSTI]

    Zand, Jean in 't; Cavecchi, Yuri

    2014-01-01T23:59:59.000Z

    We study the exceptionally short (32-41 ms) precursors of two intermediate-duration thermonuclear X-ray bursts observed with RXTE from the neutron stars in 4U 0614+09 and 2S 0918-549. They exhibit photon fluxes that surpass those at the Eddington limit later in the burst by factors of 2.6 to 3.1. We are able to explain both the short duration and the super-Eddington flux by mildly relativistic outflow velocities of 0.1$c$ to 0.3$c$ subsequent to the thermonuclear shell flashes on the neutron stars. These are the highest velocities ever measured from any thermonuclear flash. The precursor rise times are also exceptionally short: about 1 ms. This is inconsistent with predictions for nuclear flames spreading laterally as deflagrations and suggests detonations instead. This is the first time that a detonation is suggested for such a shallow ignition column depth ($y_{\\rm ign}$ = 10$^{10}$ g cm$^{-2}$). The detonation would possibly require a faster nuclear reaction chain, such as bypassing the alpha-capture on $^...

  3. A methodology for experimentally verifying simulation models for distribution transformer internal faults

    E-Print Network [OSTI]

    Palmer-Buckle, Peter

    1999-01-01T23:59:59.000Z

    Internal winding faults comprise 70-80% of modem transformer breakdown. In this era of deregulation, this phenomenon is likely to increase since loading transformers to their optimum capacity is becoming normal practice. These internal faults result...

  4. Extension of thermonuclear functions through the pathway model including Maxwell-Boltzmann and Tsallis distributions

    E-Print Network [OSTI]

    H. J. Haubold; D. Kumar

    2007-08-16T23:59:59.000Z

    The Maxwell-Boltzmannian approach to nuclear reaction rate theory is extended to cover Tsallis statistics (Tsallis, 1988) and more general cases of distribution functions. An analytical study of respective thermonuclear functions is being conducted with the help of statistical techniques. The pathway model, recently introduced by Mathai (2005), is utilized for thermonuclear functions and closed-form representations are obtained in terms of H-functions and G-functions. Maxwell-Boltzmannian thermonuclear functions become particular cases of the extended thermonuclear functions. A brief review on the development of the theory of analytic representations of nuclear reaction rates is given.

  5. RECENT EXPERIMENTAL STUDIES OF EDGE AND INTERNAL TRANSPORT BARRIERS IN THE DIII-D TOKAMAK

    SciTech Connect (OSTI)

    P. GOHIL; L.R. BAYLOR; K.H. BURRELL; T.A. CASPER; E.J. DOYLE; C.M. GREENFIELD; T.C. JERNIGAN; J.E. KINSEY; C.J LASNIER; R.A. MOYER; M. MURAKAMI; T.L. RHODES; D.L. RUDAKOV; G.M. STAEBLER; G. WANG; J.G. WATKINS; W.P. WEST; L.ZENG

    2002-08-01T23:59:59.000Z

    Results from recent experiments on the DIII-D tokamak have revealed many important details on transport barriers at the plasma edge and in the plasma core. These experiments include: (a) the formation of the H-mode edge barrier directly by pellet injection; (b) the formation of a quiescent H-mode edge barrier (QH-mode) which is free from edge localized modes (ELMs), but which still exhibits good density and radiative power control; (c) the formation of multiple transport barriers, such as the quiescent double barrier (QDB) which combines a internal transport barrier with the quiescent H-mode edge barrier. Results from the pellet-induced H-mode experiments indicate that: (a) the edge temperature (electron or ion) is not a critical parameter for the formation of the H-mode barrier, (b) pellet injection leads to an increased gradient in the radial electric field, E{sub r}, at the plasma edge; (c) the experimentally determined edge parameters at barrier transition are well below the predictions of several theories on the formation of the H-mode barrier, (d) pellet injection can lower the threshold power required to form the H-mode barrier. The quiescent H-mode barrier exhibits good density control as the result of continuous magnetohydrodynamic (MHD) activity at the plasma edge called the edge harmonic oscillation (EHO). The EHO enhances the edge particle transport while maintaining a good energy transport barrier. The ability to produce multiple barriers in the QDB regime has led to long duration, high performance plasmas with {beta}{sub NH{sub 89}} values of 7 for up to 10 times the confinement time. Density profile control in the plasma core of QDB plasmas has been demonstrated using on-axis ECH.

  6. arabidopsis converts benzaldehyde: Topics by E-print Network

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

    CERN Preprints Summary: The International Thermonuclear Experimental Reactor (ITER) is a thermonuclear fusion experiment designed to provide long deuterium tritium burning...

  7. ac-line matrix-reactance converter: Topics by E-print Network

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

    CERN Preprints Summary: The International Thermonuclear Experimental Reactor (ITER) is a thermonuclear fusion experiment designed to provide long deuterium tritium burning...

  8. advanced converter reactors: Topics by E-print Network

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

    CERN Preprints Summary: The International Thermonuclear Experimental Reactor (ITER) is a thermonuclear fusion experiment designed to provide long deuterium tritium burning...

  9. alpha converting enzyme: Topics by E-print Network

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

    CERN Preprints Summary: The International Thermonuclear Experimental Reactor (ITER) is a thermonuclear fusion experiment designed to provide long deuterium tritium burning...

  10. MASSACHUSETTS INSTITUTE OF TECHNOLOGY PLASMA FUSI0.N CENTER

    E-Print Network [OSTI]

    . The International Thermonuclear Experimental Reactor (ITER), a superconducting device, is being designed to achieve transport processes and alpha heating effectiveness,[2] at the re- quired thermonuclear conditions

  11. Thermonuclear Explosions of Chandrasekhar-Mass White Dwarfs

    E-Print Network [OSTI]

    W. Hillebrandt; M. Reinecke; J. C. Niemeyer

    2000-05-16T23:59:59.000Z

    We present a new way of modeling turbulent thermonuclear deflagration fronts in Chandrasekhar-mass white dwarfs, consisting of carbon and oxygen, undergoing a type Ia supernova explosion. Our approach is a front capturing/tracking hybrid scheme, based on a level set method, which treats the front as a mathematical discontinuity and allows for full coupling between the front geometry and the flow field. First results of the method applied to the problem of type Ia supernovae are discussed. It will be shown that even in 2-D and even with a physically motivated sub-grid model numerically ``converged'' results are difficult to obtain.

  12. Simulations of Turbulent Thermonuclear Burning in Type Ia Supernovae

    E-Print Network [OSTI]

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

    2004-05-11T23:59:59.000Z

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

  13. On the Evolution of Thermonuclear Flames on Large Scales

    E-Print Network [OSTI]

    Ju Zhang; O. E. Bronson Messer; Alexei M. Khokhlov; Tomasz Plewa

    2006-10-05T23:59:59.000Z

    The thermonuclear explosion of a massive white dwarf in a Type Ia supernova explosion is characterized by vastly disparate spatial and temporal scales. The extreme dynamic range inherent to the problem prevents the use of direct numerical simulation and forces modelers to resort to subgrid models to describe physical processes taking place on unresolved scales. We consider the evolution of a model thermonuclear flame in a constant gravitational field on a periodic domain. The gravitational acceleration is aligned with the overall direction of the flame propagation, making the flame surface subject to the Rayleigh-Taylor instability. The flame evolution is followed through an extended initial transient phase well into the steady-state regime. The properties of the evolution of flame surface are examined. We confirm the form of the governing equation of the evolution suggested by Khokhlov (1995). The mechanism of vorticity production and the interaction between vortices and the flame surface are discussed. The results of our investigation provide the bases for revising and extending previous subgrid-scale model.

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

    E-Print Network [OSTI]

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

    2004-12-07T23:59:59.000Z

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

  15. Faint Thermonuclear Supernovae from AM Canum Venaticorum Binaries

    E-Print Network [OSTI]

    Lars Bildsten; Ken J. Shen; Nevin N. Weinberg; Gijs Nelemans

    2007-05-06T23:59:59.000Z

    Helium that accretes onto a Carbon/Oxygen white dwarf in the double white dwarf AM Canum Venaticorum (AM CVn) binaries undergoes unstable thermonuclear flashes when the orbital period is in the 3.5-25 minute range. At the shortest orbital periods (and highest accretion rates, Mdot > 10^-7 Msol/yr), the flashes are weak and likely lead to the Helium equivalent of classical nova outbursts. However, as the orbit widens and Mdot drops, the mass required for the unstable ignition increases, leading to progressively more violent flashes up to a final flash with Helium shell mass ~ 0.02-0.1 Msol. The high pressures of these last flashes allow the burning to produce the radioactive elements 48Cr, 52Fe, and 56Ni that power a faint (M_V in the range of -15 to -18) and rapidly rising (few days) thermonuclear supernova. Current galactic AM CVn space densities imply one such explosion every 5,000-15,000 years in 10^11 Msol of old stars (~ 2-6% of the Type Ia rate in E/SO galaxies). These ".Ia" supernovae (one-tenth as bright for one-tenth the time as a Type Ia supernovae) are excellent targets for deep (e.g. V=24) searches with nightly cadences, potentially yielding an all-sky rate of 1,000 per year.

  16. Cosmic and Galactic Neutrino Backgrounds from Thermonuclear Sources

    E-Print Network [OSTI]

    Cristiano Porciani; Silvia Petroni; Giovanni Fiorentini

    2003-11-20T23:59:59.000Z

    We estimate energy spectra and fluxes at the Earth's surface of the cosmic and Galactic neutrino backgrounds produced by thermonuclear reactions in stars. The extra-galactic component is obtained by combining the most recent estimates of the cosmic star formation history and the stellar initial mass function with accurate theoretical predictions of the neutrino yields all over the thermonuclear lifetime of stars of different masses. Models of the structure and evolution of the Milky Way are used to derive maps of the expected flux generated by Galactic sources as a function of sky direction. The predicted neutrino backgrounds depend only slightly on model parameters. In the relevant 50 keV-10 MeV window, the total flux of cosmic neutrinos ranges between 20 and 65 particles per square cm per s. Neutrinos reaching the Earth today have been typically emitted at redshift z~2. Their energy spectrum peaks at E~0.1-0.3 MeV. The energy and entropy densities of the cosmic background are negligible with respect to the thermal contribution of relic neutrinos originated in the early universe. In every sky direction, the cosmic background is outnumbered by the Galactic one, whose integrated flux amounts to 300-1000 particles per square cm per s. The emission from stars in the Galactic disk contributes more than 95 per cent of the signal.

  17. A time-delay approach for the modeling and control of plasma instabilities in thermonuclear fusion

    E-Print Network [OSTI]

    Sipahi, Rifat

    for thermonuclear fusion plasmas. Indeed, advanced plasma confinement scenarios, such as the ones considered1 A time-delay approach for the modeling and control of plasma instabilities in thermonuclear fusion Emmanuel WITRANT, Erik OLOFSSON, Silviu-Iulian NICULESCU, March 13, 2009. Abstract This letter

  18. On the thermonuclear runaway in Type Ia supernovae: How to run away

    E-Print Network [OSTI]

    P. Höflich; J. Stein

    2002-01-01T23:59:59.000Z

    Type Ia Supernovae are thought to be thermonuclear explosions of massive white dwarfs (WD). We present the first study of multi-dimensional effects during the final hours prior to the thermonuclear runaway which leads to the explosion. The calculations utilize an implicit, 2-D hydrodynamical code

  19. Astrophysical Thermonuclear Functions for Boltzmann-Gibbs Statistics and Tsallis Statistics

    E-Print Network [OSTI]

    R. K. Saxena; A. M. Mathai; H. J. Haubold

    2004-06-22T23:59:59.000Z

    We present an analytic proof of the integrals for astrophysical thermonuclear functions which are derived on the basis of Boltzmann-Gibbs statistical mechanics. Among the four different cases of astrophysical thermonuclear functions, those with a depleted high-energy tail and a cut-off at high energies find a natural interpretation in q-statistics.

  20. A Systematic Approach to the Design of a Large Scale Detritiation System for Controlled Thermonuclear Fusion Experiments

    E-Print Network [OSTI]

    A Systematic Approach to the Design of a Large Scale Detritiation System for Controlled Thermonuclear Fusion Experiments

  1. Thermonuclear rates of the 28Si(p, y) reaction M. Kicinska-Habior and T. Matulewicz

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    1881 Thermonuclear rates of the 28Si(p, y) reaction M. Kicinska-Habior and T. Matulewicz Institute Thermonuclear reaction rates NA av > are the quan- tities of essential importance for models of stellar in a much more extended energy range. The thermonuclear rates of the 28Si(p, y) reaction, although it does

  2. Tidally-induced thermonuclear Supernovae Stephan Rosswog1, Enrico Ramirez-Ruiz2, W. Raphael Hix3

    E-Print Network [OSTI]

    Rosswog, Stephan

    Tidally-induced thermonuclear Supernovae Stephan Rosswog1, Enrico Ramirez-Ruiz2, W. Raphael Hix3 1 in a thermonuclear explosion. These explosions are not restricted to progenitor masses close to the Chandrasekhar thermonuclear supernova together with an X-ray flare thus whistle-blows the existence of such moderate

  3. Experimental simulation of internal short circuit in Li-ion and Li-ion-Polymer cells

    SciTech Connect (OSTI)

    Cai, Wei [ORNL; Wang, Hsin [ORNL; Maleki, Hossein [Motorola Mobility; Howard, Jason [Motorola Mobility; Lara-Curzio, Edgar [ORNL

    2011-01-01T23:59:59.000Z

    A multi-parameter controlled pinch test was developed to study the occurrence of internal short circuits in Li-ion and Li-ion-polymer cells. By tuning the control parameters (i.e., cell voltage as well as pinching area, load, and speed), the pinch test can reproducibly create ~1 to 2 mm wide internal short between a cell jelly-roll s inner layer electrodes. This recreates conditions similar to those that may occur during service. Furthermore, the pinch test is used to determine thermal stability of two Li-ion-polymer cells of different designs built by the same manufacturer. The pinch test method can be used to help distinguish cells with design features or characteristics that lower risk of potential thermal events created by internal short circuits.

  4. On the stability of thermonuclear shell sources in stars

    E-Print Network [OSTI]

    S. -C. Yoon; N. Langer; M. van der Sluys

    2004-06-07T23:59:59.000Z

    We present a quantitative criterion for the thermal stability of thermonuclear shell sources. We find the thermal stability of shell sources to depend on exactly three factors: they are more stable when they are geometrically thicker, less degenerate and hotter. This confirms and unifies previously obtained results in terms of the geometry, temperature and density of the shell source, by a simplified but quantitative approach to the physics of shell nuclear burning. We present instability diagrams in the temperature-density plane for hydrogen and helium shell burning, which allow a simple evaluation of the stability conditions of such shell sources in stellar models. The performance of our stability criterion is demonstrated in various numerical models: in a 3 Msun AGB star, in helium accreting CO white dwarfs, in a helium white dwarf which is covered by a thin hydrogen envelope, and in a 1.0 Msun giant.

  5. The Periods Discovered by RXTE in Thermonuclear Flash Bursts

    E-Print Network [OSTI]

    T. E. Strohmayer; J. H. Swank; W. Zhang

    1998-01-23T23:59:59.000Z

    Oscillations in the X-ray flux of thermonuclear X-ray bursts have been observed with RXTE from at least 6 low-mass binaries, at frequencies from 330 Hz to 589 Hz. There appear to be preferred relations between the frequencies present during the bursts and those seen in the persistent flux. The amplitude of the oscillations can exceed 50 % near burst onset. Except for a systematic increase in oscillation frequency as the burst progresses, the frequency is stable. Time resolved spectra track increases in the X-ray emitting area due to propagation of the burning front over the neutron star surface, as well as radiation driven expansion of the photosphere. The neutron star mass, radius, and distance can be inferred when spectra are compared to theoretical expectations.

  6. Screening in Thermonuclear Reaction Rates in the Sun

    E-Print Network [OSTI]

    Andrei V. Gruzinov; John N. Bahcall

    1998-01-20T23:59:59.000Z

    We evaluate the effect of electrostatic screening by ions and electrons on low-Z thermonuclear reactions in the sun. We use a mean field formalism and calculate the electron density of the screening cloud using the appropriate density matrix equation of quantum statistical mechanics. Because of well understood physical effects that are included for the first time in our treatment, the calculated enhancement of reaction rates does not agree with the frequently used interpolation formulae. Our result does agree, within small uncertainties, with Salpeter's weak screening formula. If weak screening is used instead of the commonly employed screening prescription of Graboske et al., the predicted $^8$B neutrino flux is increased by 7% and the predicted chlorine rate is increased by 0.4 SNU.

  7. Experimental investigation of turbine blade platform film cooling and rotational effect on trailing edge internal cooling

    E-Print Network [OSTI]

    Wright, Lesley Mae

    2009-06-02T23:59:59.000Z

    The present work has been an experimental investigation to evaluate the applicability of gas turbine cooling technology. With the temperature of the mainstream gas entering the turbine elevated above the melting temperature of the metal components...

  8. Measurement of neutron capture on 50Ti at thermonuclear energies

    E-Print Network [OSTI]

    P. V. Sedyshev; P. Mohr; H. Beer; H. Oberhummer; Yu. P. Popov; W. Rochow

    1999-07-28T23:59:59.000Z

    At the Karlsruhe and Tuebingen 3.75 MV Van de Graaff accelerators the thermonuclear 50Ti(n,gamma)51Ti(5.8 min) cross section was measured by the fast cyclic activation technique via the 320.852 and 928.65 keV gamma-ray lines of the 51Ti-decay. Metallic Ti samples of natural isotopic composition and samples of TiO2 enriched in 50Ti by 67.53 % were irradiated between two gold foils which served as capture standards. The capture cross-section was measured at the neutron energies 25, 30, 52, and 145 keV, respectively. The direct capture cross section was determined to be 0.387 +/- 0.011 mbarn at 30 keV. We found evidence for a bound state s-wave resonance with an estimated radiative width of 0.34 eV which destructively interfers with direct capture. The strength of a suggested s-wave resonance at 146.8 keV was determined. The present data served to calculate, in addition to the directly measured Maxwellian averaged capture cross sections at 25 and 52 keV, an improved stellar 50Ti(n,gamma)51Ti rate in the thermonuclear energy region from 1 to 250 keV. The new stellar rate leads at low temperatures to much higher values than the previously recommended rate, e.g., at kT=8 keV the increase amounts to about 50 %. The new reaction rate therefore reduces the abundance of 50Ti due to s-processing in AGB stars.

  9. Detonating Failed Deflagration Model of Thermonuclear Supernovae I. Explosion Dynamics

    E-Print Network [OSTI]

    Tomasz Plewa

    2006-11-24T23:59:59.000Z

    We present a detonating failed deflagration model of Type Ia supernovae. In this model, the thermonuclear explosion of a massive white dwarf follows an off-center deflagration. We conduct a survey of asymmetric ignition configurations initiated at various distances from the stellar center. In all cases studied, we find that only a small amount of stellar fuel is consumed during deflagration phase, no explosion is obtained, and the released energy is mostly wasted on expanding the progenitor. Products of the failed deflagration quickly reach the stellar surface, polluting and strongly disturbing it. These disturbances eventually evolve into small and isolated shock-dominated regions which are rich in fuel. We consider these regions as seeds capable of forming self-sustained detonations that, ultimately, result in the thermonuclear supernova explosion. Preliminary nucleosynthesis results indicate the model supernova ejecta are typically composed of about 0.1-0.25 Msun of silicon group elements, 0.9-1.2 Msun of iron group elements, and are essentially carbon-free. The ejecta have a composite morphology, are chemically stratified, and display a modest amount of intrinsic asymmetry. The innermost layers are slightly egg-shaped with the axis ratio ~1.2-1.3 and dominated by the products of silicon burning. This central region is surrounded by a shell of silicon-group elements. The outermost layers of ejecta are highly inhomogeneous and contain products of incomplete oxygen burning with only small admixture of unburned stellar material. The explosion energies are ~1.3-1.5 10^51 erg.

  10. A bright thermonuclear X-ray burst simultaneously observed with Chandra and RXTE

    E-Print Network [OSTI]

    in ’t Zand, J. J. M.

    The prototypical accretion-powered millisecond pulsar SAX J1808.4?3658 was observed simultaneously with Chandra-LETGS and RXTE-PCA near the peak of a transient outburst in November 2011. A single thermonuclear (type-I) ...

  11. Application of variational techniques for parametric studies of steady-state controlled thermonuclear reactor blankets 

    E-Print Network [OSTI]

    Pearce, James David

    1975-01-01T23:59:59.000Z

    APPLICATION OF VARIATIONAL TECHNIQUES FOR PARAMETRIC STUDIES OF STEADY-STATE CONTROLLED THERMONUCLEAR REACTOR BLANKETS A Thesis JAMES DAVID PEARCE Submitted to the Graduate College of Texas A6M University in partial fulfillment... of the requirement for the degree of MASTER OP SCIENCE May 1975 Ma)or Subject: Nuclear Engineering APPLICATION OF VARIATIONAL TECHNIQUES FOR PARAMETRIC STUDIES OF STEADY-STATE CONTROLLED THERMONUCLEAR REACTOR BLANKETS A Thesis by JAMES DAVID PEARCE Approved...

  12. Application of variational techniques for parametric studies of steady-state controlled thermonuclear reactor blankets

    E-Print Network [OSTI]

    Pearce, James David

    1975-01-01T23:59:59.000Z

    APPLICATION OF VARIATIONAL TECHNIQUES FOR PARAMETRIC STUDIES OF STEADY-STATE CONTROLLED THERMONUCLEAR REACTOR BLANKETS A Thesis JAMES DAVID PEARCE Submitted to the Graduate College of Texas A6M University in partial fulfillment... of the requirement for the degree of MASTER OP SCIENCE May 1975 Ma)or Subject: Nuclear Engineering APPLICATION OF VARIATIONAL TECHNIQUES FOR PARAMETRIC STUDIES OF STEADY-STATE CONTROLLED THERMONUCLEAR REACTOR BLANKETS A Thesis by JAMES DAVID PEARCE Approved...

  13. Experimental determination of radiated internal wave power without pressure field data

    SciTech Connect (OSTI)

    Lee, Frank M.; Morrison, P. J. [Physics Department and Institute for Fusion Studies, The University of Texas at Austin, Austin, Texas 78712–1192 (United States)] [Physics Department and Institute for Fusion Studies, The University of Texas at Austin, Austin, Texas 78712–1192 (United States); Paoletti, M. S.; Swinney, Harry L. [Physics Department, The University of Texas at Austin, Austin, Texas 78712–1192 (United States)] [Physics Department, The University of Texas at Austin, Austin, Texas 78712–1192 (United States)

    2014-04-15T23:59:59.000Z

    We present a method to determine, using only velocity field data, the time-averaged energy flux (J) and total radiated power P for two-dimensional internal gravity waves. Both (J) and P are determined from expressions involving only a scalar function, the stream function ?. We test the method using data from a direct numerical simulation for tidal flow of a stratified fluid past a knife edge. The results for the radiated internal wave power given by the stream function method agree to within 0.5% with results obtained using pressure and velocity data from the numerical simulation. The results for the radiated power computed from the stream function agree well with power computed from the velocity and pressure if the starting point for the stream function computation is on a solid boundary, but if a boundary point is not available, care must be taken to choose an appropriate starting point. We also test the stream function method by applying it to laboratory data for tidal flow past a knife edge, and the results are found to agree with the direct numerical simulation. The supplementary material includes a Matlab code with a graphical user interface that can be used to compute the energy flux and power from two-dimensional velocity field data.

  14. Reaction Rate and Composition Dependence of the Stability of Thermonuclear Burning on Accreting Neutron Stars

    E-Print Network [OSTI]

    Keek, L; Heger, A

    2014-01-01T23:59:59.000Z

    The stability of thermonuclear burning of hydrogen and helium accreted onto neutron stars is strongly dependent on the mass accretion rate. The burning behavior is observed to change from Type I X-ray bursts to stable burning, with oscillatory burning occurring at the transition. Simulations predict the transition at a ten times higher mass accretion rate than observed. Using numerical models we investigate how the transition depends on the hydrogen, helium, and CNO mass fractions of the accreted material, as well as on the nuclear reaction rates of triple alpha and the hot-CNO breakout reactions 15O(a,g)19Ne and 18Ne(a,p)21Na. For a lower hydrogen content the transition is at higher accretion rates. Furthermore, most experimentally allowed reaction rate variations change the transition accretion rate by at most 10%. A factor ten decrease of the 15O(a,g)19Ne rate, however, produces an increase of the transition accretion rate of 35%. None of our models reproduce the transition at the observed rate, and depend...

  15. Nucleosynthesis in type Ia supernovae driven by asymmetric thermonuclear ignition

    SciTech Connect (OSTI)

    Maeda, Keiichi [Institute for the Physics and Mathematics of the Universe (IPMU), Todai Institutes for Advanced Study (TODIAS), University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8583 (Japan)

    2012-11-12T23:59:59.000Z

    Type Ia Supernovae (SNe Ia) are believed to be thermonuclear explosions of a white dwarf. They can be used as mature cosmological standardized candles, leading to the discovery of the accelerating expansion of the Universe. However, the explosion mechanism has not yet been fully clarified. In this paper, we first present nucleosynthetic features of a leading explosion scenario, namely a delayed-detonation scenario. Based on this, we propose a new and strong observational constraint on the explosion mechanism through emission lines from neutron-rich Fe-peaks. Especially, we show that an asymmetry in the explosion is likely a generic feature. We further argue that the diversity arising from various viewing angles can be an origin of observational diversities of SNe Ia seen in their spectral features (suspected possible biases in cosmology) and colors (related to the extinction estimate in cosmology). Using these new insights could open up a possibility of using SNe Ia as more precise distance indicators than currently employed.

  16. Wideband Heterodyne QWIP Receiver Development for Thermonuclear Fusion Measurements

    SciTech Connect (OSTI)

    Bennett, C.A.; Buchanan, M.; Hutchinson, D.P.; Liu, H.C.; Richards, R.K.; Simpson, M.L.

    1998-11-01T23:59:59.000Z

    Oak Ridge National Laboratory (ORNL) has been developing heterodyne receivers for plasma diagnostic applications for over 20 years. One area of this work has been the development of a diagnostic system for the measurement of the energy of alpha particles created in a thermonuclear fusion reactor. These particles originate with an energy of 3.5 MeV and cool to the thermal energy of the plasma (around 15 keV) after several seconds. To measure the velocity distribution of these alpha particles, a Thomson scattering diagnostic is under development based on a high power CO{sub 2} laser at 10 microns with a heterodyne receiver. The Doppler shift generated by Thomson scattering of the alpha particles requires a wideband heterodyne receiver (greater than 10 GHz). Because Mercury-Cadimum-Telluride (MCT) detectors are limited to a bandwidth of approximately 2 GHz, a Quantum Well Infrared Photodetector (QWIP) detector was obtained from the National Research Council of Canada (NRC) and evaluated for its heterodyne performance using the heterodyne testing facility developed at ORNL.

  17. The cooling rate of neutron stars after thermonuclear shell flashes

    E-Print Network [OSTI]

    Zand, J J M in 't; Triemstra, T L; Mateijsen, R A D A; Bagnoli, T

    2013-01-01T23:59:59.000Z

    Thermonuclear shell flashes on neutron stars are detected as bright X-ray bursts. Traditionally, their decay is modeled with an exponential function. However, this is not what theory predicts. The expected functional form for luminosities below the Eddington limit, at times when there is no significant nuclear burning, is a power law. We tested the exponential and power-law functional forms against the best data available: bursts measured with the high-throughput Proportional Counter Array (PCA) on board the Rossi X-ray Timing Explorer. We selected a sample of 35 'clean' and ordinary (i.e., shorter than a few minutes) bursts from 14 different neutron stars that 1) show a large dynamic range in luminosity, 2) are the least affected by disturbances by the accretion disk and 3) lack prolonged nuclear burning through the rp-process. We find indeed that for every burst a power law is a better description than an exponential function. We also find that the decay index is steep, 1.8 on average, and different for eve...

  18. The NACRE Thermonuclear Reaction Compilation and Big Bang Nucleosynthesis

    E-Print Network [OSTI]

    Richard H. Cyburt; Brian D. Fields; Keith A. Olive

    2001-05-17T23:59:59.000Z

    The theoretical predictions of big bang nucleosynthesis (BBN) are dominated by uncertainties in the input nuclear reaction cross sections. In this paper, we examine the impact on BBN of the recent compilation of nuclear data and thermonuclear reactions rates by the NACRE collaboration. We confirm that the adopted rates do not make large overall changes in central values of predictions, but do affect the magnitude of the uncertainties in these predictions. Therefore, we then examine in detail the uncertainties in the individual reaction rates considered by NACRE. When the error estimates by NACRE are treated as 1\\sigma limits, the resulting BBN error budget is similar to those of previous tabulations. We propose two new procedures for deriving reaction rate uncertainties from the nuclear data: one which sets lower limits to the error, and one which we believe is a reasonable description of the present error budget. We propagate these uncertainty estimates through the BBN code, and find that when the nuclear data errors are described most accurately, the resulting light element uncertainties are notably smaller than in some previous tabulations, but larger than others. Using these results, we derive limits on the cosmic baryon-to-photon ratio $\\eta$, and compare this to independent limits on $\\eta$ from recent balloon-borne measurements of the cosmic microwave background radiation (CMB). We discuss means to improve the BBN results via key nuclear reaction measurements and light element observations.

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

    E-Print Network [OSTI]

    Andrew Cumming

    2003-11-18T23:59:59.000Z

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

  20. Experimental Highlights

    E-Print Network [OSTI]

    Dainton, John

    2010-01-01T23:59:59.000Z

    Highlights at the 13th International Conference on Elastic & Diffractive Scattering (EDS09) of the presentations of new experimental results and developments are presented and discussed.

  1. The Sensitivity of Nucleosynthesis in Type I X-ray Bursts to Thermonuclear Reaction-Rate Variations

    E-Print Network [OSTI]

    Anuj Parikh; Jordi Jose; Fermin Moreno; Christian Iliadis

    2008-06-18T23:59:59.000Z

    We examine the sensitivity of nucleosynthesis in Type I X-ray bursts to variations in nuclear rates. As a large number of nuclear processes are involved in these phenomena -with the vast majority of reaction rates only determined theoretically due to the lack of any experimental information- our results can provide a means for determining which rates play significant roles in the thermonuclear runaway. These results may then motivate new experiments. For our studies, we have performed a comprehensive series of one-zone post-processing calculations in conjunction with various representative X-ray burst thermodynamic histories. We present those reactions whose rate variations have the largest effects on yields in our studies.

  2. Astrophysical S-factors of proton radiative capture for thermonuclear reactions

    E-Print Network [OSTI]

    S. B. Dubovichenko; A. V. Dzhazairov-Kakhramanov

    2011-12-09T23:59:59.000Z

    In this review we have considered the possibility to describe the astrophysical S-factors of radiative capture reactions with light atomic nuclei on the basis of the potential two-cluster model by taking into account the splitting the orbital states according to Young's schemes. Within this model, interaction of the nucleon clusters is described by local two-particle potential determined by fit to the scattering data and properties of bound states of these clusters. Many-body character of the problem is taken into account under some approximation, in terms of the allowed or forbidden by the Pauli principle states in intercluster potentials. An important feature of the approach is accounting for a dependence of interaction potential between clusters on the orbital Young scheme, which determines the permutation symmetry of the nucleon system. The astrophysical S-factors of the radiative capture processes in the p2H, p7Li and p12C systems are analyzed on the basis of this approach. It is shown that the approach allows one to describe quite reasonably experimental data available at low energies, when the phase shifts of cluster-cluster scattering are extracted from the data with minimal errors. In this connection the problem of experimental error decrease is exclusively urgent for the differential cross-sections of elastic scattering of light atomic nuclei at astrophysical energies and to perform a more accurate phase shift analysis. The increase in the accuracy will allow, in future, making more definite conclusions regarding the mechanisms and conditions of thermonuclear reactions, as well as understanding better their nature in general.

  3. Study of internal magnetic field via polarimetry in fusion plasmas

    E-Print Network [OSTI]

    Zhang, Jie

    2013-01-01T23:59:59.000Z

    Motivation Controlled thermonuclear fusion is a promising2007]. Controlled thermonuclear fusion is based on the

  4. Thermonuclear Stability of Material Accreting onto a Neutron Star

    E-Print Network [OSTI]

    Ramesh Narayan; Jeremy S. Heyl

    2003-08-22T23:59:59.000Z

    We present a global linear stability analysis of nuclear fuel accumulating on the surface of an accreting neutron star and we identify the conditions under which thermonuclear bursts are triggered. The analysis reproduces all the recognized regimes of hydrogen and helium bursts, and in addition shows that at high accretion rates, near the limit of stable burning, there is a regime of ``delayed mixed bursts'' which is distinct from the more usual ``prompt mixed bursts.'' In delayed mixed bursts, a large fraction of the fuel is burned stably before the burst is triggered. Bursts thus have longer recurrence times, but at the same time have somewhat smaller fluences. Therefore, the parameter alpha, which measures the ratio of the energy released via accretion to that generated through nuclear reactions in the burst, is up to an order of magnitude larger than for prompt bursts. This increase in alpha near the threshold of stable burning has been seen in observations. We explore a wide range of mass accretion rates, neutron star radii and core temperatures, and calculate a variety of burst properties. From a preliminary comparison with data, we suggest that bursting neutron stars may have hot cores, with T_{core} >~ 10^{7.5} K, consistent with interior cooling via the modified URCA or similar low-efficiency process, rather than T_{core} ~ 10^7 K, as expected for the direct URCA process. There is also an indication that neutron star radii are somewhat small <~ 10 km. Both of these conclusions need to be confirmed by comparing more careful calculations with better data.

  5. First direct evidence that filament fracture accompanies degradation of superconducting cables designed for the

    E-Print Network [OSTI]

    Weston, Ken

    designed for the International Thermonuclear Experimental Reactor (ITER) ­ The tokomak fusion reactor ITER generation from nuclear fusion. Eighteen toroidal field coils, each weighing 363 tons, will confine High Magnetic Field Laboratory; 2. International Thermonuclear Experimental Reactor (ITER) Organization

  6. Kinetic simulation of thermonuclear-neutron production by a 10{sup 7}-A deuterium Z pinch

    SciTech Connect (OSTI)

    Welch, D. R.; Rose, D. V.; Thoma, C.; Clark, R. E.; Mostrom, C. B. [Voss Scientific, LLC, Albuquerque, New Mexico 87108 (United States); Stygar, W. A.; Leeper, R. J. [Sandia National Laboratories, Albuquerque, New Mexico 87185-1196 (United States)

    2010-07-15T23:59:59.000Z

    Fully kinetic simulations have demonstrated that at sufficiently high currents, half of the neutrons produced by a deuterium Z-pinch are thermonuclear in origin. At 150-kA pinch current, O. A. Anderson et al. [Phys. Rev. 110, 1375 (1958)] clearly shows that essentially all of the neutrons produced by a deuterium pinch are not thermonuclear, but are initiated by an instability that creates beam-target neutrons. Since this paper, many subsequent authors have supported this result while others have claimed that pinch neutrons are, on the contrary, thermonuclear. To resolve this issue, fully kinetic, collisional, and electromagnetic simulations of the complete time evolution of a deuterium pinch have been performed. The simulations were performed with the implicit particle-in-cell code LSP, as described in D. R. Welch et al. [Phys. Rev. Lett. 103, 255002 (2009)]. At 10{sup 6} -A pinch currents, most of the neutrons are, indeed, beam-target in origin. At 15-MA current, half of the neutrons are thermonuclear and half are beam-target driven by instabilities that produce a power law fall off in the ion energy distribution function at large energy. Simulation results suggest that from 7- to 15-MA current, the fraction of thermonuclear neutrons is not sensitive to current and that the strong dependence of neutron yield on current will continue at currents greater than 15 MA.

  7. Experimental study of curved guide tubes for pellet injection

    SciTech Connect (OSTI)

    Combs, S.K.; Baylor, L.R.; Foust, C.R.; Gouge, M.J.; Jernigan, T.C.; Milora, S.L.

    1997-12-01T23:59:59.000Z

    The use of curved guide tubes for transporting frozen hydrogen pellets offers great flexibility for pellet injection into plasma devices. While this technique has been previously employed, an increased interest in its applicability has been generated with the recent ASDEX Upgrade experimental data for magnetic high-field side (HFS) pellet injection. In these innovative experiments, the pellet penetration appeared to be significantly deeper than for the standard magnetic low-field side injection scheme, along with corresponding greater fueling efficiencies. Thus, some of the major experimental fusion devices are planning experiments with HFS pellet injection. Because of the complex geometries of experimental fusion devices, installations with multiple curved guide tube sections will be required for HFS pellet injection. To more thoroughly understand and document the capability of curved guide tubes, an experimental study is under way at the Oak Ridge National Laboratory (ORNL). In particular, configurations and pellet parameters applicable for the DIII-D tokamak and the International Thermonuclear Experimental Reactor (ITER) were simulated in laboratory experiments. Initial test results with nominal 2.7- and 10-mm-diam deuterium pellets are presented and discussed.

  8. U.S. Department of Energy Office of Inspector General Annual...

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

    Carbon Fiber Technology Center The Department of Energy's International Thermonuclear Experimental Reactor (ITER) Responsibilities Depleted Uranium Operations at...

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

    E-Print Network [OSTI]

    F. K. Roepke; W. Hillebrandt

    2004-04-26T23:59:59.000Z

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

  10. English home Forum Photo Gallery Features Newsletter Archive About US Help Site Map languages Culture/Life

    E-Print Network [OSTI]

    to build its own thermonuclear experimental reactor A leading Chinese plasma physicist said Thursday China might build its own thermonuclear experimental reactor, which would be expected to supply sustained in thermonuclear reaction, Chinese scientists have already participated in the International Thermonuclear

  11. International Collaborations on Engineered Barrier Systems: Experiment...

    Energy Savers [EERE]

    International Collaborations on Engineered Barrier Systems: Experimental and Modeling Investigations International Collaborations on Engineered Barrier Systems: Experimental and...

  12. Contrib. Plasma Phys. 53, No. 45, 397 405 (2013) / DOI 10.1002/ctpp.201200094 Electron screening effect on stellar thermonuclear fusion

    E-Print Network [OSTI]

    2013-01-01T23:59:59.000Z

    effect on stellar thermonuclear fusion Alexander Y. Potekhin1,2 and Gilles Chabrier2,3 1 Ioffe Physical. In addition, we examine some recent unconventional theo- retical results on stellar thermonuclear fusionsA, Weinheim 1 Introduction Thermonuclear reactions play a crucial role in stellar evolution. Nuclear fusion

  13. Mon. Not. R. Astron. Soc. 401, 26 (2010) doi:10.1111/j.1365-2966.2009.15632.x Systematic variation in the apparent burning area of thermonuclear

    E-Print Network [OSTI]

    Miller, Cole

    2010-01-01T23:59:59.000Z

    in the apparent burning area of thermonuclear bursts and its implication for neutron star radius measurement Sudip area during the decay portions of thermonuclear (type I) X-ray bursts. However, this apparent area are challenging. Thermonuclear bursts provide one of the very few promising methods to measure the neutron star

  14. PHYS 390 Lecture 20 -Reactions III -Thermonuclear processes 20 -1 2001 by David Boal, Simon Fraser University. All rights reserved; further resale or copying is strictly prohibited.

    E-Print Network [OSTI]

    Boal, David

    PHYS 390 Lecture 20 - Reactions III - Thermonuclear processes 20 - 1 © 2001 by David Boal, Simon - Reactions III - Thermonuclear processes What's Important: · energy-dependent cross sections · complete rate 20 - Reactions III - Thermonuclear processes 20 - 2 © 2001 by David Boal, Simon Fraser University

  15. Toward the Development of Radiation-Tolerant Instrumentation Data Links for Thermonuclear Fusion Experiments

    E-Print Network [OSTI]

    Alberto Fernandez Fernandez; Ez Fern; F. Berghmans; B. Brichard; M. Decreton

    2002-01-01T23:59:59.000Z

    Thermonuclear reactors will require permanent monitoring under high-gamma dose rates and high neutron flux. We propose to get rid of the digital data transmission limitations in highly radioactive environments by implementing an analog fiber-optic link based on directly modulated vertical

  16. Complex workplace radiation fields at European high-energy accelerators and thermonuclear fusion facilities

    E-Print Network [OSTI]

    Bilski, P; D'Errico, F; Esposito, A; Fehrenbacher, G; Fernàndez, F; Fuchs, A; Golnik, N; Lacoste, V; Leuschner, A; Sandri, S; Silari, M; Spurny, F; Wiegel, B; Wright, P

    2006-01-01T23:59:59.000Z

    This report outlines the research needs and research activities within Europe to develop new and improved methods and techniques for the characterization of complex radiation fields at workplaces around high-energy accelerators and the next generation of thermonuclear fusion facilities under the auspices of the COordinated Network for RAdiation Dosimetry (CONRAD) project funded by the European Commission.

  17. Millihertz quasi-periodic oscillations and thermonuclear bursts from Terzan 5: A showcase of burning regimes

    E-Print Network [OSTI]

    Linares, M.

    We present a comprehensive study of the thermonuclear bursts and millihertz quasi-periodic oscillations (mHz QPOs) from the neutron star (NS) transient and 11 Hz X-ray pulsar IGR J17480–2446, located in the globular cluster ...

  18. Estimation of a Noise Level Using Coarse-Grained Entropy of Experimental Time Series of Internal Pressure in a Combustion Engine

    E-Print Network [OSTI]

    Grzegorz Litak; Rodolfo Taccani; Krzysztof Urbanowicz; Janusz A. Holyst; Miroslaw Wendeker; Alessandro Giadrossi

    2004-05-22T23:59:59.000Z

    We report our results on non-periodic experimental time series of pressure in a single cylinder spark ignition engine. The experiments were performed for different levels of loading. We estimate the noise level in internal pressure calculating the coarse-grained entropy from variations of maximal pressures in successive cycles. The results show that the dynamics of the combustion is a nonlinear multidimensional process mediated by noise. Our results show that so defined level of noise in internal pressure is not monotonous function of loading.

  19. Energy limits on runaway electrons in tokamak plasmas J. R. Martin-Solisa)

    E-Print Network [OSTI]

    Martín-Solís, José Ramón

    runaway electrons in JET and the projected International Thermonuclear Experimental Reactor ITER ITER EDA International Thermonuclear Experi- mental Reactor ITER 1 where larger amounts of runaway electrons than those

  20. Also on the agenda would be

    E-Print Network [OSTI]

    the multi- billion dollar International Thermonuclear Experimental Reactor (ITER), one of the most exciting the multi-billion dollar International Thermonuclear Experimental Reactor (ITER), one of the most exciting International Thermonuclear French President Jacques Chirac Six Month World Exposition Beijing Tiananmen Square

  1. CONDENSATION IN EJECTA FROM DENSE THERMONUCLEAR SUPERNOVAE. T. Yu1, B. S. Meyer1, A. V. Fedkin2, and L. Grossman2,3, 1Department of Physics and Astronomy, Clemson University, Clemson, SC

    E-Print Network [OSTI]

    Grossman, Lawrence

    CONDENSATION IN EJECTA FROM DENSE THERMONUCLEAR SUPERNOVAE. T. Yu1, B. S. Meyer1, A. V. Fedkin2 Thermonuclear Supernova Model: Thermonuclear (Type Ia) supernovae are explosions of white dwarf stars. Our model and then oxy- gen burning proceed under degenerate conditions, a thermonuclear runaway occurs, which leads

  2. A meeting is planned Tuesday

    E-Print Network [OSTI]

    Thermonuclear Experimental Reactor (ITER) -- a test bed for what is being billed as a safe and inexhaustible | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Google It: International Thermonuclear Spokesman Fabio Fabbi Questions Eu Optimism Experimental Reactor

  3. Charged-Particle Thermonuclear Reaction Rates: III. Nuclear Physics Input

    E-Print Network [OSTI]

    Christian Iliadis; Richard Longland; Art Champagne; Alain Coc

    2010-04-23T23:59:59.000Z

    The nuclear physics input used to compute the Monte Carlo reaction rates and probability density functions that are tabulated in the second paper of this series (Paper II) is presented. Specifically, we publish the input files to the Monte Carlo reaction rate code RatesMC, which is based on the formalism presented in the first paper of this series (Paper I). This data base contains overwhelmingly experimental nuclear physics information. The survey of literature for this review was concluded in November 2009.

  4. THE FERMI-GBM X-RAY BURST MONITOR: THERMONUCLEAR BURSTS FROM 4U 0614+09

    E-Print Network [OSTI]

    Connaughton, V.

    Thermonuclear bursts from slowly accreting neutron stars (NSs) have proven difficult to detect, yet they are potential probes of the thermal properties of the NS interior. During the first year of a systematic all-sky ...

  5. The development of an experimental procedure to determine the amount of active internal friction in a rotor-bearing system

    E-Print Network [OSTI]

    Parker, Jeffrey Scott

    1997-01-01T23:59:59.000Z

    frequency equivalent viscous friction coefficient (Coulomb friction) equivalent viscous friction coefficient (hys', cretic friction) Young's modulus (psi) internal friction force per unit length (lbs) total shaft internal friction force (lbs... friction force is now generally believed to be hysteretic (resistance to elongation and contraction of material fibers, also called anelasticity) or Coulomb (relative motion between two materials at a joint) rather ihan viscous. In 1976, II. F. Black...

  6. Thermonuclear fusion in dense stars: Electron screening, conductive cooling, and magnetic field effects

    E-Print Network [OSTI]

    Potekhin, A Y

    2012-01-01T23:59:59.000Z

    We study the plasma correlation effects on nonresonant thermonuclear reactions of carbon and oxygen in the interiors of white dwarfs and liquid envelopes of neutron stars. We examine the effects of electron screening on thermodynamic enhancement of thermonuclear reactions in dense plasmas beyond the linear mixing rule. Using these improved enhancement factors, we calculate carbon and oxygen ignition curves in white dwarfs and neutron stars. The energy balance and ignition conditions in neutron star envelopes are evaluated, taking their detailed thermal structure into account. The result is compared to the simplified "one-zone model," which is routinely used in the literature. We also consider the effect of strong magnetic fields on the ignition curves in the ocean of magnetars.

  7. Level set simulations of turbulent thermonuclear deflagration in degenerate carbon and oxygen

    E-Print Network [OSTI]

    Schmidt, W; Niemeyer, J C

    2005-01-01T23:59:59.000Z

    We study the dynamics of thermonuclear flames propagating in fuel stirred by stochastic forcing. The fuel consists of carbon and oxygen in a state which is encountered in white dwarfs close to the Chandrasekhar limit. The level set method is applied to represent the flame fronts numerically. The computational domain for the numerical simulations is cubic, and periodic boundary conditions are imposed. The goal is the development of a suitable flame speed model for the small-scale dynamics of turbulent deflagration in thermonuclear supernovae. Because the burning process in a supernova explosion is transient and spatially inhomogeneous, the localised determination of subgrid scale closure parameters is essential. We formulate a semi-localised model based on the dynamical equation for the subgrid scale turbulence energy $k_{\\mathrm{sgs}}$. The turbulent flame speed $s_{\\mathrm{t}}$ is of the order $\\sqrt{2k_{\\mathrm{sgs}}}$. In particular, the subgrid scale model features a dynamic procedure for the calculation ...

  8. Compression and combustion of non-cryogenic targets with a solid thermonuclear fuel for inertial fusion

    SciTech Connect (OSTI)

    Gus'kov, S. Yu., E-mail: guskov@sci.lebedev.ru [Russian Academy of Sciences, Lebedev Physical Institute (Russian Federation); Zmitrenko, N. V. [Russian Academy of Sciences, Keldysh Institute of Applied Mathematics (Russian Federation); Sherman, V. E. [St. Petersburg State Polytechnic University (Russian Federation)

    2013-04-15T23:59:59.000Z

    Variants of a target with a solid thermonuclear fuel in the form of deuterium-tritium hydrides of light metals for an inertial fusion have been proposed. The laser-pulse-induced compression of non-cryogenic targets, as well as ignition and combustion of such targets, has been examined. The numerical calculations show that, despite a decrease in the caloric content of the fuel and an increase in the energy losses on intrinsic radiation in the target containing deuterium-tritium hydrides of light metals as compared to the target containing deuterium-tritium ice, the non-cryogenic target can ensure the fusion gain sufficient for its use in the energy cycle of a thermonuclear power plant based on the inertial plasma confinement method.

  9. Oscillations During Thermonuclear X-ray Bursts: A New Probe of Neutron Stars

    E-Print Network [OSTI]

    Tod E. Strohmayer

    1999-11-19T23:59:59.000Z

    Observations of thermonuclear (Type I) X-ray bursts from neutron stars in low mass X-ray binaries (LMXB) with the Rossi X-ray Timing Explorer (RXTE) have revealed large amplitude, high coherence X-ray brightness oscillations with frequencies in the 300 - 600 Hz range. Substantial spectral and timing evidence point to rotational modulation of the X-ray burst flux as the cause of these oscillations, and it is likely that they reveal the spin frequencies of neutron stars in LMXB from which they are detected. Here I review the status of our knowledge of these oscillations and describe how they can be used to constrain the masses and radii of neutron stars as well as the physics of thermonuclear burning on accreting neutron stars.

  10. The variation of the fine structure constant: testing the dipole model with thermonuclear supernovae

    E-Print Network [OSTI]

    Kraiselburd, Lucila; Negrelli, Carolina; Berro, Enrique García

    2014-01-01T23:59:59.000Z

    The large-number hypothesis conjectures that fundamental constants may vary. Accordingly, the spacetime variation of fundamental constants has been an active subject of research for decades. Recently, using data obtained with large telescopes a phenomenological model in which the fine structure constant might vary spatially has been proposed. We test whether this hypothetical spatial variation of {\\alpha}, which follows a dipole law, is compatible with the data of distant thermonuclear supernovae. Unlike previous works, in our calculations we consider not only the variation of the luminosity distance when a varying {\\alpha} is adopted, but we also take into account the variation of the peak luminosity of Type Ia supernovae resulting from a variation of {\\alpha}. This is done using an empirical relation for the peak bolometric magnitude of thermonuclear supernovae that correctly reproduces the results of detailed numerical simulations. We find that there is no significant difference between the several phenome...

  11. A revised thermonuclear rate of $^{7}$Be($n$,$\\alpha$)$^{4}$He relevant to Big-Bang nucleosynthesis

    E-Print Network [OSTI]

    Hou, S Q; Kubono, S; Chen, Y S

    2015-01-01T23:59:59.000Z

    In the standard Big-Bang nucleosynthesis (BBN) model, the primordial $^7$Li abundance is overestimated by about a factor of 2--3 comparing to the astronomical observations, so called the pending cosmological lithium problem. The $^7$Be($n$,$\\alpha$)$^4$He reaction, which may affect the $^7$Li abundance, was regarded as the secondary important reaction in destructing the $^7$Be nucleus in BBN. However, the thermonuclear rate of $^7$Be($n$,$\\alpha$)$^4$He has not been well studied so far. This reaction rate was firstly estimated by Wagoner in 1969, which has been generally adopted in the current BBN simulations and the reaction rate library. This simple estimation involved only a direct-capture reaction mechanism, but the resonant contribution should be also considered according to the later experimental results. In this work, we have revised this rate based on the indirect cross-section data available for the $^4$He($\\alpha$,$n$)$^7$Be and $^4$He($\\alpha$,$p$)$^7$Li reactions, with the charge symmetry and deta...

  12. Hydrodynamic simulations of a combined hydrogen, helium thermonuclear runaway on a 10-km neutron star

    SciTech Connect (OSTI)

    Starrfield, S.; Kenyon, S.; Truran, J.W.; Sparks, W.M.

    1983-01-01T23:59:59.000Z

    We have used a Lagrangian, hydrodynamic stellar-evolution computer code to evolve a thermonuclear runaway in the accreted hydrogen rich envelope of a 1.0M, 10-km neutron star. Our simulation produced an outburst which lasted about 2000 sec and peak effective temperature was 3 keV. The peak luminosity exceeded 2 x 10/sup 5/ L. A shock wave caused a precursor in the light curve which lasted 10/sup -5/ sec.

  13. Application of a new screening model to thermonuclear reactions of the rp process

    E-Print Network [OSTI]

    Theodore Liolios

    2003-05-09T23:59:59.000Z

    A new screening model for astrophysical thermonuclear reactions was derived recently which improved Salpeter's weak-screening one. In the present work we prove that the new model can also give very reliable screening enhancement factors (SEFs) when applied to the rp process. According to the results of the new model, which agree well with Mitler's SEFs, the screened rp reaction rates can be, at most, twice as fast as the unscreened ones.

  14. MILLIHERTZ QUASI-PERIODIC OSCILLATIONS AND THERMONUCLEAR BURSTS FROM TERZAN 5: A SHOWCASE OF BURNING REGIMES

    SciTech Connect (OSTI)

    Linares, M.; Chakrabarty, D. [Massachusetts Institute of Technology, Kavli Institute for Astrophysics and Space Research, Cambridge, MA 02139 (United States); Altamirano, D. [Astronomical Institute 'Anton Pannekoek', University of Amsterdam and Center for High-Energy Astrophysics, P.O. BOX 94249, 1090 GE Amsterdam (Netherlands); Cumming, A. [Department of Physics, McGill University, 3600 Rue University, Montreal, QC H3A 2T8 (Canada); Keek, L. [School of Physics and Astronomy, University of Minnesota, 116 Church Street SE, Minneapolis, MN 55455 (United States)

    2012-04-01T23:59:59.000Z

    We present a comprehensive study of the thermonuclear bursts and millihertz quasi-periodic oscillations (mHz QPOs) from the neutron star (NS) transient and 11 Hz X-ray pulsar IGR J17480-2446, located in the globular cluster Terzan 5. The increase in burst rate that we found during its 2010 outburst, when persistent luminosity rose from 0.1 to 0.5 times the Eddington limit, is in qualitative agreement with thermonuclear burning theory yet contrary to all previous observations of thermonuclear bursts. Thermonuclear bursts gradually evolved into a mHz QPO when the accretion rate increased, and vice versa. The mHz QPOs from IGR J17480-2446 resemble those previously observed in other accreting NSs, yet they feature lower frequencies (by a factor {approx}3) and occur when the persistent luminosity is higher (by a factor 4-25). We find four distinct bursting regimes and a steep (close to inverse cubic) decrease of the burst recurrence time with increasing persistent luminosity. We compare these findings to nuclear burning models and find evidence for a transition between the pure helium and mixed hydrogen/helium ignition regimes when the persistent luminosity was about 0.3 times the Eddington limit. We also point out important discrepancies between the observed bursts and theory, which predicts brighter and less frequent bursts, and suggest that an additional source of heat in the NS envelope is required to reconcile the observed and expected burst properties. We discuss the impact of NS magnetic field and spin on the expected nuclear burning regimes, in the context of this particular pulsar.

  15. Lightcurves of thermonuclear supernovae as a probe of the explosion mechanism and their use in cosmology

    E-Print Network [OSTI]

    S. Blinnikov; E. Sorokina

    2002-12-30T23:59:59.000Z

    Thermonuclear supernovae are valuable for cosmology but their physics is not yet fully understood. Modeling the development and propagation of nuclear flame is complicated by numerous instabilities. The predictions of supernova light curves still involve some simplifying assumptions, but one can use the comparison of the computed fluxes with observations to constrain the explosion mechanism. In spite of great progress in recent years, a number of issues remains unsolved both in flame physics and light curve modeling.

  16. Thermonuclear Runaways on Accreting White Dwarfs: Models of Classical Novae Explosions

    E-Print Network [OSTI]

    Margarita Hernanz; Jordi Jose

    2000-01-11T23:59:59.000Z

    The mechanism of classical novae explosions is explained, together with some of their observational properties. The scarce but not null impact of novae in the chemical evolution of the Milky Way is analyzed, as well as their relevance for the radioactivity in the Galaxy. A special emphasis is given to the predicted gamma-ray emission from novae and its relationship with the thermonuclear model itself and its related nucleosynthesis.

  17. Thermonuclear explosion of rotating massive stars could explain core-collapse supernovae

    E-Print Network [OSTI]

    Kushnir, Doron

    2015-01-01T23:59:59.000Z

    It is widely thought that core-collapse supernovae (CCSNe), the explosions of massive stars following the collapse of the stars' iron cores, is obtained due to energy deposition by neutrinos. So far, this scenario was not demonstrated from first principles. Kushnir and Katz (2014) have recently shown, by using one-dimensional simulations, that if the neutrinos failed to explode the star, a thermonuclear explosion of the outer shells is possible for some (tuned) initial profiles. However, the energy released was small and negligible amounts of ejected $^{56}$Ni were obtained, implying that these one-dimensional collapse induced thermonuclear explosions (CITE) are unlikely to represent typical CCSNe. Here I provide evidence supporting a scenario in which the majority of CCSNe are the result of CITE. I use two-dimensional simulations to show that collapse of stars that include slowly (few percent of breakup) rotating $\\sim0.1-10\\,M_{\\odot}$ shells of mixed helium-oxygen, leads to an ignition of a thermonuclear d...

  18. Experimental Analysis of the Single-Phase Heat Transfer and Friction Factor inside the Horizontal Internally Micro-Fin Tube

    E-Print Network [OSTI]

    Ghajar, Afshin J.

    ; micro-fin tube I. INTRODUCTION Single-phase liquid flow in internally enhanced tubes is becoming more of tube is widely used in high flow rate applications because the heat transfer enhancement in high flow that the secondary flow inside the tube with longitudinal fins was insignificant in the laminar flow and the thermal

  19. U.S. and China Announce Cooperation on FutureGen and Sign Energy...

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

    a Hydrogen Economy; the Carbon Sequestration Leadership Forum; the International Thermonuclear Experimental Reactor; and the Generation IV International Forum. Secretary Bodman...

  20. Evidence for a New Path to the Self-Sustainment of the Thermonuclear Fusion Reactions in Magnetically Confined Burning Plasma Experiments

    E-Print Network [OSTI]

    Evidence for a New Path to the Self-Sustainment of the Thermonuclear Fusion Reactions in Magnetically Confined Burning Plasma Experiments

  1. Accepted Manuscript Making Tungsten Work

    E-Print Network [OSTI]

    Raffray, A. René

    Thermonuclear Experimental Reactor Organization, Cadarache, FRANCE 3 Plasma Science and Fusion Center at MIT International Thermonuclear Experimental Reactor Organization, Cadarache, FRANCE 3 Plasma Science and Fusion Thermonuclear Experimental Reactor). Tungsten (W) is the plasma-facing material of choice in several design

  2. A Characterization of the Brightness Oscillations During Thermonuclear Bursts From 4U 1636-536

    E-Print Network [OSTI]

    M. Coleman Miller

    1999-04-08T23:59:59.000Z

    The discovery of nearly coherent brightness oscillations during thermonuclear X-ray bursts from six neutron-star low-mass X-ray binaries has opened up a new way to study the propagation of thermonuclear burning, and may ultimately lead to greater understanding of thermonuclear propagation in other astrophysical contexts, such as in Type Ia supernovae. Here we report detailed analyses of the ~580 Hz brightness oscillations during bursts from 4U 1636-536. We investigate the bursts as a whole and, in more detail, the initial portions of the bursts. We analyze the ~580 Hz oscillations in the initial 0.75 seconds of the five bursts that were used in a previous search for a brightness oscillation at the expected ~290 Hz spin frequency, and find that if the same frequency model describes all five bursts there is insufficient data to require more than a constant frequency or, possibly, a frequency plus a frequency derivative. Therefore, although it is appropriate to use an arbitrarily complicated model of the ~580 Hz oscillations to generate a candidate waveform for the ~290 Hz oscillations, models with more than two parameters are not required by the data. For the bursts as a whole we show that the characteristics of the brightness oscillations vary greatly from burst to burst. We find, however, that in at least one of the bursts, and possibly in three of the four that have strong brightness oscillations throughout the burst, the oscillation frequency reaches a maximum several seconds into the burst and then decreases. This behavior has not been reported previously for burst brightness oscillations, and it poses a challenge to the standard burning layer expansion explanation for the frequency changes.

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

    E-Print Network [OSTI]

    P. Hoeflich; J. Stein

    2001-12-07T23:59:59.000Z

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

  4. Charged-Particle Thermonuclear Reaction Rates: IV. Comparison to Previous Work

    E-Print Network [OSTI]

    Christian Iliadis; Richard Longland; Art Champagne; Alain Coc

    2010-04-23T23:59:59.000Z

    We compare our Monte Carlo reaction rates (see Paper II of this series) to previous results that were obtained by using the classical method of computing thermonuclear reaction rates. For each reaction, the comparison is presented using two types of graphs: the first shows the change in reaction rate uncertainties, while the second displays our new results normalized to the previously recommended reaction rate. We find that the rates have changed significantly for almost all reactions considered here. The changes are caused by (i) our new Monte Carlo method of computing reaction rates (see Paper I of this series), and (ii) newly available nuclear physics information (see Paper III of this series).

  5. Enhancement of Resonant Thermonuclear Reaction Rates in Extremely Dense Stellar Plasmas

    E-Print Network [OSTI]

    Naoki Itoh; Nami Tomizawa; Shinya Wanajo; Satoshi Nozawa

    2002-12-06T23:59:59.000Z

    The enhancement factor of the resonant thermonuclear reaction rates is calculated for the extremely dense stellar plasmas in the liquid phase. In order to calculate the enhancement factor we use the screening potential which is deduced from the numerical experiment of the classical one-component plasma. It is found that the enhancement is tremendous for white dwarf densities if the ^{12}C + ^{12}C fusion cross sections show resonant behavior in the astrophysical energy range. We summarize our numerical results by accurate analytic fitting formulae.

  6. A revised thermonuclear rate of $^{7}$Be($n$,$?$)$^{4}$He relevant to Big-Bang nucleosynthesis

    E-Print Network [OSTI]

    S. Q. Hou; J. J. He; S. Kubono; Y. S. Chen

    2015-02-13T23:59:59.000Z

    In the standard Big-Bang nucleosynthesis (BBN) model, the primordial $^7$Li abundance is overestimated by about a factor of 2--3 comparing to the astronomical observations, so called the pending cosmological lithium problem. The $^7$Be($n$,$\\alpha$)$^4$He reaction, which may affect the $^7$Li abundance, was regarded as the secondary important reaction in destructing the $^7$Be nucleus in BBN. However, the thermonuclear rate of $^7$Be($n$,$\\alpha$)$^4$He has not been well studied so far. This reaction rate was firstly estimated by Wagoner in 1969, which has been generally adopted in the current BBN simulations and the reaction rate library. This simple estimation involved only a direct-capture reaction mechanism, but the resonant contribution should be also considered according to the later experimental results. In this work, we have revised this rate based on the indirect cross-section data available for the $^4$He($\\alpha$,$n$)$^7$Be and $^4$He($\\alpha$,$p$)$^7$Li reactions, with the charge symmetry and detailed-balance principle. Our new result shows that the previous rate (acting as an upper limit) is overestimated by about a factor of ten. The BBN simulation shows that the present rate leads to a 1.2\\% increase in the final $^7$Li abundance compared to the result using the Wagoner rate, and hence the present rate even worsens the $^7$Li problem. By the present estimation, the role of $^7$Be($n$,$\\alpha$)$^4$He in destroying $^7$Be is weakened from the secondary importance to the third, and the $^7$Be($d$,$p$)2$^4$He reaction becomes of secondary importance in destructing $^7$Be.

  7. thermonuclear functions

    E-Print Network [OSTI]

    M. Aslam Chaudhry

    1999-01-01T23:59:59.000Z

    Two representations of the extended gamma functions ? 2,0 0,2 [(b,x)] are proved. These representations are exploited to find a transformation relation between two Fox’s H-functions. These results are used to solve Fox’s H-function in terms of Meijer’s G-function for certain values of the parameters. A closed form representation of the kernel of the Bessel type integral transform is also proved. 1.

  8. Thermonuclear Flame Spreading on Rapidly Spinning Neutron Stars: Indications of the Coriolis Force?

    E-Print Network [OSTI]

    Sudip Bhattacharyya; Tod E. Strohmayer

    2007-08-27T23:59:59.000Z

    Millisecond period brightness oscillations during the intensity rise of thermonuclear X-ray bursts are likely caused by an azimuthally asymmetric, expanding burning region on the stellar surface. The time evolution of the oscillation amplitude during the intensity rise encodes information on how the thermonuclear flames spread across the stellar surface. This process depends on properties of the accreted burning layer, surface fluid motions, and the surface magnetic field structure, and thus can provide insight into these stellar properties. We present two examples of bursts from different sources that show a decrease in oscillation amplitude during the intensity rise. Using theoretical modeling, we demonstrate that the observed amplitude evolution of these bursts is not well described by a uniformly expanding circular burning region. We further show that by including in our model the salient aspects of the Coriolis force (as described by Spitkovsky, Levin, and Ushomirsky) we can qualitatively reproduce the observed evolution curves. Our modeling shows that the evolutionary structure of burst oscillation amplitude is sensitive to the nature of flame spreading, while the actual amplitude values can be very useful to constrain some source parameters.

  9. Relics of metal-free low mass stars exploding as thermonuclear supernovae

    E-Print Network [OSTI]

    Takuji Tsujimoto; Toshikazu Shigeyama

    2006-01-16T23:59:59.000Z

    Renewed interest in the first stars that were formed in the universe has led to the discovery of extremely iron-poor stars. Since several competing scenarios exist, our understanding of the mass range that determines the observed elemental abundances remains unclear. In this study, we consider three well-studied metal-poor stars in terms of the theoretical supernovae (SNe) model. Our results suggest that the observed abundance patterns in the metal-poor star BD +80 245 and the pair of stars HD 134439/40 agree strongly with the theoretical possibility that these stars inherited their heavy element abundance patterns from SNe initiated by thermonuclear runaways in the degenerate carbon-oxygen cores of primordial asymptotic giant branch stars with \\~3.5-5 solar masses. Recent theoretical calculations have predicted that such SNe could be originated from metal-free stars in the intermediate mass range. On the other hand, intermediate mass stars containing some metals would end their lives as white dwarfs after expelling their envelopes in the wind due to intense momentum transport from outgoing photons to heavy elements. This new pathway for the formation of SNe requires that stars are formed from the primordial gas. Thus, we suggest that stars of a few solar masses were formed from the primordial gas and that some of them caused thermonuclear explosions when the mass of their degenerate carbon-oxygen cores increased to the Chandrasekhar limit without experiencing efficient mass loss.

  10. Magnetic burial and the harmonic content of millisecond oscillations in thermonuclear X-ray bursts

    E-Print Network [OSTI]

    D. J. B. Payne; A. Melatos

    2006-07-11T23:59:59.000Z

    Matter accreting onto the magnetic poles of a neutron star spreads under gravity towards the magnetic equator, burying the polar magnetic field and compressing it into a narrow equatorial belt. Steady-state, Grad-Shafranov calculations with a self-consistent mass-flux distribution (and a semi-quantitative treatment of Ohmic diffusion) show that, for $\\Ma \\gtrsim 10^{-5}\\Msun$, the maximum field strength and latitudinal half-width of the equatorial magnetic belt are $B_{\\rm max} = 5.6\\times 10^{15} (\\Ma/10^{-4}\\Msun)^{0.32}$ G and $\\Delta\\theta = \\max[3^{\\circ} (\\Ma/10^{-4}\\Msun)^{-1.5},3^{\\circ} (\\Ma/10^{-4}\\Msun)^{0.5}(\\dot{M}_{\\rm a}/10^{-8}\\Msun {\\rm yr}^{-1})^{-0.5}]$ respectively, where $\\Ma$ is the total accreted mass and $\\dot{M}_{\\rm a}$ is the accretion rate. It is shown that the belt prevents north-south heat transport by conduction, convection, radiation, and ageostrophic shear. This may explain why millisecond oscillations observed in the tails of thermonuclear (type I) X-ray bursts in low-mass X-ray binaries are highly sinusoidal: the thermonuclear flame is sequestered in the magnetic hemisphere which ignites first. The model is also consistent with the occasional occurrence of closely spaced pairs of bursts. Time-dependent, ideal-magnetohydrodynamic simulations confirm that the equatorial belt is not disrupted by Parker and interchange instabilities.

  11. Level set simulations of turbulent thermonuclear deflagration in degenerate carbon and oxygen

    E-Print Network [OSTI]

    W. Schmidt; W. Hillebrandt; J. C. Niemeyer

    2005-08-02T23:59:59.000Z

    We study the dynamics of thermonuclear flames propagating in fuel stirred by stochastic forcing. The fuel consists of carbon and oxygen in a state which is encountered in white dwarfs close to the Chandrasekhar limit. The level set method is applied to represent the flame fronts numerically. The computational domain for the numerical simulations is cubic, and periodic boundary conditions are imposed. The goal is the development of a suitable flame speed model for the small-scale dynamics of turbulent deflagration in thermonuclear supernovae. Because the burning process in a supernova explosion is transient and spatially inhomogeneous, the localised determination of subgrid scale closure parameters is essential. We formulate a semi-localised model based on the dynamical equation for the subgrid scale turbulence energy $k_{\\mathrm{sgs}}$. The turbulent flame speed $s_{\\mathrm{t}}$ is of the order $\\sqrt{2k_{\\mathrm{sgs}}}$. In particular, the subgrid scale model features a dynamic procedure for the calculation of the turbulent energy transfer from resolved toward subgrid scales, which has been successfully applied to combustion problems in engineering. The options of either including or suppressing inverse energy transfer in the turbulence production term are compared. In combination with the piece-wise parabolic method for the hydrodynamics, our results favour the latter option. Moreover, different choices for the constant of proportionality in the asymptotic flame speed relation, $s_{\\mathrm{t}}\\propto\\sqrt{2k_{\\mathrm{sgs}}}$, are investigated.

  12. Relativistic collapse and explosion of rotating supermassive stars with thermonuclear effects

    E-Print Network [OSTI]

    Pedro J. Montero; Hans-Thomas Janka; Ewald Mueller

    2012-02-01T23:59:59.000Z

    We present results of general relativistic simulations of collapsing supermassive stars with and without rotation using the two-dimensional general relativistic numerical code Nada, which solves the Einstein equations written in the BSSN formalism and the general relativistic hydrodynamics equations with high resolution shock capturing schemes. These numerical simulations use an equation of state which includes effects of gas pressure, and in a tabulated form those associated with radiation and the electron-positron pairs. We also take into account the effect of thermonuclear energy released by hydrogen and helium burning. We find that objects with a mass of 5x10^{5} solar mass and an initial metallicity greater than Z_{CNO}~0.007 do explode if non-rotating, while the threshold metallicity for an explosion is reduced to Z_{CNO}~0.001 for objects uniformly rotating. The critical initial metallicity for a thermonuclear explosion increases for stars with mass ~10^{6} solar mass. For those stars that do not explode we follow the evolution beyond the phase of black hole formation. We compute the neutrino energy loss rates due to several processes that may be relevant during the gravitational collapse of these objects. The peak luminosities of neutrinos and antineutrinos of all flavors for models collapsing to a BH are ~10^{55} erg/s. The total radiated energy in neutrinos varies between ~10^{56} ergs for models collapsing to a BH, and ~10^{45}-10^{46} ergs for models exploding.

  13. Thermonuclear Burning on the Accreting X-Ray Pulsar GRO J1744-28

    E-Print Network [OSTI]

    Lars Bildsten; Edward F. Brown

    1996-09-23T23:59:59.000Z

    We investigate the thermal stability of nuclear burning on the accreting X-ray pulsar GRO J1744-28. The neutron star's dipolar magnetic field is thermonuclear instabilities are unlikely causes of the hourly bursts seen at very high accretion rates. We then discuss how the stability of the thermonuclear burning depends on both the global accretion rate and the neutron star's magnetic field strength. We emphasize that the appearance of the instability (i.e., whether it looks like a Type I X-ray burst or a flare lasting a few minutes) will yield crucial information on the neutron star's surface magnetic field and the role of magnetic fields in convection. We suggest that a thermal instability in the accretion disk is the origin of the long (~300 days) outburst and that the recurrence time of these outbursts is >50 years. We also discuss the nature of the binary and point out that a velocity measurement of the stellar companion (most likely a Roche-lobe filling giant with m_K>17) will constrain the neutron star mass.

  14. Contents of ITER deal revealed The Yomiuri Shimbun (May 27, 2005, 4 am)

    E-Print Network [OSTI]

    in thermonuclear fusion. The country also will supply 20 percent of workers to ITER facilities. The four other on the roles of host and non-hosting countries involved in the International Thermonuclear Experimental Reactor. The planned ITER is an experimental facility for a thermonuclear reactor designed to produce power by fusing

  15. Thermonuclear yield of targets under the action of high-power short-wavelength (lambda< or =1. mu. ) lasers

    SciTech Connect (OSTI)

    Basov, N.G.; Gus'kov, S.Y.; Danilova, G.V.; Demchenko, N.N.; Zmitrenko, N.V.; Karpov, V.Y.; Mishchenko, T.V.; Rozanov, V.B.; Samarskii, A.A.

    1985-06-01T23:59:59.000Z

    A unified optimization scheme is used in a numerical calculation of the dependences of the thermonuclear yield of two-layer shell targets on the absorbed laser energy in the range 0.3--10 mJ for lasers emitting radiation of wavelengths shorter than 1 ..mu...

  16. Spreading of thermonuclear flames on the neutron star in SAX J1808.4-3658: an observational tool

    E-Print Network [OSTI]

    Sudip Bhattacharyya; Tod E. Strohmayer

    2006-04-03T23:59:59.000Z

    We analyse archival Rossi X-Ray Timing Explorer (RXTE) proportional counter array (PCA) data of thermonuclear X-ray bursts from the 2002 outburst of the accreting millisecond pulsar SAX J1808.4-3658. We present evidence of nonmonotonic variations of oscillation frequency during burst rise, and correlations among the time evolution of the oscillation frequency, amplitude, and the inferred burning region area. We also discuss that the amplitude and burning region area evolutions are consistent with thermonuclear flame spreading on the neutron star surface. Based on this discussion, we infer that for the 2002 Oct. 15 thermonuclear burst, the ignition likely occured in the mid-latitudes, the burning region took ~ 0.2 s to nearly encircle the equatorial region of the neutron star, and after that the lower amplitude oscillation originated from the remaining asymmetry of the burning front in the same hemisphere where the burst ignited. Our observational findings and theoretical discussion indicate that studies of the evolution of burst oscillation properties during burst rise can provide a powerful tool to understand thermonuclear flame spreading on neutron star surfaces under extreme physical conditions.

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

    E-Print Network [OSTI]

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

    1999-05-07T23:59:59.000Z

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

  18. Lower hybrid current drive at plasma densities required for thermonuclear reactors

    SciTech Connect (OSTI)

    Cesario, R.; Cardinali, A.; Castaldo, C.; Tuccillo, A. A.; Amicucci, L. [Associazione EURATOM/ENEA sulla Fusione, Centro Ricerche Frascati, 00044 Frascati (Italy)

    2011-12-23T23:59:59.000Z

    Driving current in high-density plasmas is essential for the progress of thermonuclear fusion energy research based on the tokamak concept. The lower hybrid current drive (LHCD) effect, is potentially the most suitable tool for driving current at large plasma radii, consistent with the needs of ITER steady state scenario. Unfortunately, experiments at reactor grade high plasma densities with kinetic profiles approaching those required for ITER, have shown problems in penetration of the LH power into the core plasma. These plasmas represent a basic reference for designing possible methods useful for assessing the LHCD concept in ITER. On the basis of the phenomenology observed during LHCD experiments carried out in different machines, and model of the spectral broadening effect due to parametric instability, an interpretation and possible solution of the related important problem is presented.

  19. Astrophysics Simulations from the ASC/Alliances Center for Astrophysical Thermonuclear Flashes

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

    The "Flash Center" works to solve the long-standing problem of thermonuclear flashes on the surfaces of compact stars such as neutron stars and white dwarfs, and in the interior of white dwarfs (i.e., Type I supernovae). The physical conditions, and many of the physical phenomena, are similar to those confronted by the Department of Energy Stockpile Stewardship program. The (fully ionized) plasmas are at very high temperatures and densities; and the physical problems of nuclear ignition, deflagration or detonation, turbulent mixing, and interface dynamics for complex multicomponent fluids are common to the weapons program. Because virtually every aspect of this problem represents a computational Grand Challenge, large-scale numerical simulations are at the heart of its resolution (Taken from Executive Summary page). More than 35 simulations and computer animations developed through research at the "Flash Center" are available here. Each .avi or .mov file also references the related research paper or presentation and provides a link.

  20. Oxygen emission in remnants of thermonuclear supernovae as a probe for their progenitor system

    E-Print Network [OSTI]

    Kosenko, D; Kromer, M; Blinnikov, S I; Pakmor, R; Kaastra, J S

    2014-01-01T23:59:59.000Z

    Recent progress in numerical simulations of thermonuclear supernova explosions brings up a unique opportunity in studying the progenitors of Type Ia supernovae. Coupling state-of-the-art explosion models with detailed hydrodynamical simulations of the supernova remnant evolution and the most up-to-date atomic data for X-ray emission calculations makes it possible to create realistic synthetic X-ray spectra for the supernova remnant phase. Comparing such spectra with high quality observations of supernova remnants could allow to constrain the explosion mechanism and the progenitor of the supernova. The present study focuses in particular on the oxygen emission line properties in young supernova remnants, since different explosion scenarios predict a different amount and distribution of this element. Analysis of the soft X-ray spectra from supernova remnants in the Large Magellanic Cloud and confrontation with remnant models for different explosion scenarios suggests that SNR 0509-67.5 could originate from a de...

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

    E-Print Network [OSTI]

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

    2003-05-02T23:59:59.000Z

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

  2. Thermonuclear Burning Regimes and the Use of SNe Ia in Cosmology

    E-Print Network [OSTI]

    E. I. Sorokina; S. I. Blinnikov; O. S. Bartunov

    1999-10-02T23:59:59.000Z

    The calculations of the light curves of thermonuclear supernovae are carried out by a method of multi-group radiation hydrodynamics. The effects of spectral lines and expansion opacity are taken into account. The predictions for UBVI fluxes are given. The values of rise time for B and V bands found in our calculations are in good agreement with the observed values. We explain why our results for the rise time have more solid physical justification than those obtained by other authors. It is shown that small variations in the chemical composition of the ejecta, produced in the explosions with different regimes of nuclear burning, can influence drastically the light curve decline in the B band and, to a lesser extent, in the V band. We argue that recent results on positive cosmological constant Lambda, found from the high redshift supernova observations, could be wrong in the case of possible variations of the preferred mode of nuclear burning in the earlier Universe.

  3. Registration of the First Thermonuclear X-ray Burst from AX J1754.2-2754

    E-Print Network [OSTI]

    I. V. Chelovekov; S. A. Grebenev

    2007-10-30T23:59:59.000Z

    During the analysis of the INTEGRAL observatory archival data we found a powerful X-ray burst, registered by JEM-X and IBIS/ISGRI telescopes on April 16, 2005 from a weak and poorly known source AX J1754.2-2754. Analysis of the burst profiles and spectrum shows, that it was a type I burst, which result from thermonuclear explosion on the surface of nutron star. It means that we can consider AX J1754.2-2754 as an X-ray burster. Certain features of burst profile at its initial stage witness of a radiation presure driven strong expansion and a corresponding cooling of the nutron star photosphere. Assuming, that the luminosity of the source at this phase was close to the Eddington limit, we estimated the distance to the burst source d=6.6+/-0.3 kpc (for hidrogen atmosphere of the neutron star) and d=9.2+/-0.4 kpc (for helium atmosphere).

  4. The fastest unbound star in our Galaxy ejected by a thermonuclear supernova

    E-Print Network [OSTI]

    Geier, S; Ziegerer, E; Kupfer, T; Heber, U; Irrgang, A; Wang, B; Liu, Z; Han, Z; Sesar, B; Levitan, D; Kotak, R; Magnier, E; Smith, K; Burgett, W S; Chambers, K; Flewelling, H; Kaiser, N; Wainscoat, R; Waters, C

    2015-01-01T23:59:59.000Z

    Hypervelocity stars (HVS) travel with velocities so high, that they exceed the escape velocity of the Galaxy. Several acceleration mechanisms have been discussed. Only one HVS (US 708, HVS 2) is a compact helium star. Here we present a spectroscopic and kinematic analysis of US\\,708. Travelling with a velocity of $\\sim1200\\,{\\rm km\\,s^{-1}}$, it is the fastest unbound star in our Galaxy. In reconstructing its trajectory, the Galactic center becomes very unlikely as an origin, which is hardly consistent with the most favored ejection mechanism for the other HVS. Furthermore, we discovered US\\,708 to be a fast rotator. According to our binary evolution model it was spun-up by tidal interaction in a close binary and is likely to be the ejected donor remnant of a thermonuclear supernova.

  5. Thermonuclear Processes for Three Body System in the Potential Cluster Model

    E-Print Network [OSTI]

    Dubovichenko, S B

    2015-01-01T23:59:59.000Z

    The manuscript is devoted to the description of the results obtained in the frame of the modified potential cluster model with the classification of states according to Young tableaux for neutron and proton radiative capture processes on 2H at thermal and astrophysical energies. It demonstrates methods of application that were obtained on the basis of phase shift analysis and characteristics of the bound states of 2H potentials for consideration of the radiative capture processes. First reaction of the proton capture directly takes part in the pp solar cycle, where it is the second reaction. The neutron capture is not a part of usual thermonuclear cycles in the Sun and stars, but can take part in the processes of primordial nucleosynthesis, following at formation and evolution of our entire Universe.

  6. Thermonuclear Processes for Three Body System in the Potential Cluster Model

    E-Print Network [OSTI]

    S. B. Dubovichenko; A. V. Dzhazairov-Kakhramanov

    2015-04-19T23:59:59.000Z

    The manuscript is devoted to the description of the results obtained in the frame of the modified potential cluster model with the classification of states according to Young tableaux for neutron and proton radiative capture processes on 2H at thermal and astrophysical energies. It demonstrates methods of application that were obtained on the basis of phase shift analysis and characteristics of the bound states of 2H potentials for consideration of the radiative capture processes. First reaction of the proton capture directly takes part in the pp solar cycle, where it is the second reaction. The neutron capture is not a part of usual thermonuclear cycles in the Sun and stars, but can take part in the processes of primordial nucleosynthesis, following at formation and evolution of our entire Universe.

  7. Analysis of the Thermonuclear Instability including Low-Power ICRH Minority Heating in IGNITOR

    E-Print Network [OSTI]

    Cardinali, Alessandro

    2014-01-01T23:59:59.000Z

    The nonlinear thermal balance equation for classical plasma in a toroidal geometry is analytically and numerically investigated including ICRH power. The determination of the equilibrium temperature and the analysis of the stability of the solution are performed by solving the energy balance equation that includes the transport relations obtained by the kinetic theory. An estimation of the confinement time is also provided. We show that the ICRH heating in the IGNITOR experiment, among other applications, is expected to stabilize the power of the thermonuclear burning by automatic regulation of the RF coupled power. Here a scenario is considered where IGNITOR is led to operate in a slightly sub-critical regime by adding a small fraction of ${}^3He$ to the nominal 50-50 Deuterium-Tritium mixture. The difference between power lost and alpha heating is compensated by additional ICRH heating, which should be able to increase the global plasma temperature via collisions between ${}^3He$ minority and the background...

  8. Spiral Disk Instability Can Drive Thermonuclear Explosions in Binary White Dwarf Mergers

    E-Print Network [OSTI]

    Kashyap, Rahul; García-Berro, Enrique; Aznar-Siguán, Gabriela; Ji, Suoqing; Lorén-Aguilar, Pablo

    2015-01-01T23:59:59.000Z

    Thermonuclear, or Type Ia supernovae (SNe Ia), originate from the explosion of carbon-oxygen white dwarfs, and serve as standardizable cosmological candles. However, despite their importance, the nature of the progenitor systems which give rise to SNe Ia has not been hitherto elucidated. Observational evidence favors the double-degenerate channel, in which merging white dwarf binaries lead to SNe Ia. Furthermore, significant discrepancies exist between observations and theory, and to date, there has been no self-consistent merger model which yields a SNe Ia. Here we show that a spiral mode instability in the accretion disk formed during a binary white dwarf merger leads to a detonation on a dynamical timescale. This mechanism sheds light on how white dwarf mergers may frequently yield SNe Ia.

  9. RELATIVISTIC COLLAPSE AND EXPLOSION OF ROTATING SUPERMASSIVE STARS WITH THERMONUCLEAR EFFECTS

    SciTech Connect (OSTI)

    Montero, Pedro J.; Janka, Hans-Thomas; Mueller, Ewald, E-mail: montero@mpa-garching.mpg.de [Max-Planck-Institut fuer Astrophysik, Karl-Schwarzschild-Str. 1, D-85748 Garching (Germany)

    2012-04-10T23:59:59.000Z

    We present results of general relativistic simulations of collapsing supermassive stars with and without rotation using the two-dimensional general relativistic numerical code Nada, which solves the Einstein equations written in the BSSN formalism and the general relativistic hydrodynamic equations with high-resolution shock-capturing schemes. These numerical simulations use an equation of state that includes the effects of gas pressure and, in a tabulated form, those associated with radiation and the electron-positron pairs. We also take into account the effect of thermonuclear energy released by hydrogen and helium burning. We find that objects with a mass of Almost-Equal-To 5 Multiplication-Sign 10{sup 5} M{sub Sun} and an initial metallicity greater than Z{sub CNO} Almost-Equal-To 0.007 do explode if non-rotating, while the threshold metallicity for an explosion is reduced to Z{sub CNO} Almost-Equal-To 0.001 for objects uniformly rotating. The critical initial metallicity for a thermonuclear explosion increases for stars with a mass Almost-Equal-To 10{sup 6} M{sub Sun }. For those stars that do not explode, we follow the evolution beyond the phase of black hole (BH) formation. We compute the neutrino energy loss rates due to several processes that may be relevant during the gravitational collapse of these objects. The peak luminosities of neutrinos and antineutrinos of all flavors for models collapsing to a BH are L{sub {nu}} {approx} 10{sup 55} erg s{sup -1}. The total radiated energy in neutrinos varies between E{sub {nu}} {approx} 10{sup 56} erg for models collapsing to a BH and E{sub {nu}} {approx} 10{sup 45}-10{sup 46} erg for models exploding.

  10. State of Advancement of the International REVE Project: Computational Modelling of Irradiation-Induced Hardening in Reactor Pressure Vessel Steels and Relevant Experimental Validation Programme

    SciTech Connect (OSTI)

    Malerba, Lorenzo; Van Walle, Eric [SCK.CEN, Boeretang 200, 2400 Mol (Belgium); Domain, Christophe; Jumel, Stephanie; Van Duysen, Jean-Claude [EDR R and D (France)

    2002-07-01T23:59:59.000Z

    The REVE (Reactor for Virtual Experiments) project is an international joint effort aimed at developing multi-scale modelling computational toolboxes capable of simulating the behaviour of materials under irradiation at different time and length scales. Well grounded numerical techniques such as molecular dynamics (MD) and Monte Carlo (MC) algorithms, as well as rate equation (RE) and dislocation-defect interaction theory, form the basis on which the project is built. The goal is to put together a suite of integrated codes capable of deducing the changes in macroscopic properties starting from a detailed simulation of the microstructural changes produced by irradiation in materials. To achieve this objective, several European laboratories are closely collaborating, while exchanging data with American and Japanese laboratories currently pursuing similar approaches. The material chosen for the first phase of this project is reactor pressure vessel (RPV) steel, the target macroscopic magnitude to be predicted being the yield strength increase ({delta}{sigma}y) due, essentially, to irradiation-enhanced formation of intragranular solute atom precipitates or clouds, as well as irradiation induced defects in the matrix, such as point defect clusters and dislocation loops. A description of the methodological approach used in the project and its current state is given in the paper. The development of the simulation tools requires a continuous feedback from ad hoc experimental data. In the framework of the REVE project SCK EN has therefore performed a neutron irradiation campaign of model alloys of growing complexity (from pure Fe to binary and ternary systems and a real RPV steel) in the Belgian test reactor BR2 and is currently carrying on the subsequent materials characterisation using its hot cell facilities. The paper gives the details of this experimental programme - probably the first large-scale one devoted to the validation of numerical simulation tools - and presents and discusses the first available results, with a view to their use as feedback for the improvement of the computational modelling. (authors)

  11. --No Title--

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

    from national laboratories and universities. Leading the list was the International Thermonuclear Experimental Reactor, a facility capable of producing a "burning plasma"...

  12. Y-12s Building 9212 and the Uranium Processing Facility, part...

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

    is the ultimate answer to the world's ever increasing need for energy. Achieving the fusion of deuterium and tritium in the International Thermonuclear Experimental Reactor is...

  13. arsenal production reactor: Topics by E-print Network

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

    to total production in India V. Dinesh Kumar 42 TRANSP simulations of International Thermonuclear Experimental Reactor plasmas Plasma Physics and Fusion Websites Summary:...

  14. E-Print Network 3.0 - advanced research reactor Sample Search...

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

    to build the world's most advanced nuclear fusion reactor... ) International Thermonuclear Experimental Reactor (ITER), which will be built at Cadarache, near the...

  15. E-Print Network 3.0 - advanced reactor technology Sample Search...

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

    Op-ed Letters... to iron out their differences over the site of the International Thermonuclear Experimental Reactor... . Russia sticks to its guns, backs France for fusion...

  16. E-Print Network 3.0 - armoured actively cooled Sample Search...

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

    on the actively cooled plasma facing components (PFCs) of the International Thermonuclear Experimental Reactor... of the actively cooled component itself. These have...

  17. Struct Multidisc Optim (2006) 32: 473484 DOI 10.1007/s00158-006-0022-1

    E-Print Network [OSTI]

    Vel, Senthil

    2006-01-01T23:59:59.000Z

    for fusion reactors, and in critical engine components, such as intake and exhaust valves. Several studies investigated for plasma facing components of the International Thermonuclear Experimental Reactor (Ueda

  18. Igniting the Light Elements: The Los Alamos Thermonuclear Weapon Project, 1942-1952

    SciTech Connect (OSTI)

    Anne C. Fitzpatrick

    1999-07-01T23:59:59.000Z

    The American system of nuclear weapons research and development was conceived and developed not as a result of technological determinism, but by a number of individual architects who promoted the growth of this large technologically-based complex. While some of the technological artifacts of this system, such as the fission weapons used in World War II, have been the subject of many historical studies, their technical successors--fusion (or hydrogen) devices--are representative of the largely unstudied highly secret realms of nuclear weapons science and engineering. In the postwar period a small number of Los Alamos Scientific Laboratory's staff and affiliates were responsible for theoretical work on fusion weapons, yet the program was subject to both the provisions and constraints of the US Atomic Energy Commission, of which Los Alamos was a part. The Commission leadership's struggle to establish a mission for its network of laboratories, least of all to keep them operating, affected Los Alamos's leaders' decisions as to the course of weapons design and development projects. Adapting Thomas P. Hughes's ''large technological systems'' thesis, I focus on the technical, social, political, and human problems that nuclear weapons scientists faced while pursuing the thermonuclear project, demonstrating why the early American thermonuclear bomb project was an immensely complicated scientific and technological undertaking. I concentrate mainly on Los Alamos Scientific Laboratory's Theoretical, or T, Division, and its members' attempts to complete an accurate mathematical treatment of the ''Super''--the most difficult problem in physics in the postwar period--and other fusion weapon theories. Although tackling a theoretical problem, theoreticians had to address technical and engineering issues as well. I demonstrate the relative value and importance of H-bomb research over time in the postwar era to scientific, politician, and military participants in this project. I analyze how and when participants in the H-bomb project recognized both blatant and subtle problems facing the project, how scientists solved them, and the relationship this process had to official nuclear weapons policies. Consequently, I show how the practice of nuclear weapons science in the postwar period became an extremely complex, technologically-based endeavor.

  19. Failure of a neutrino-driven explosion after core-collapse may lead to a thermonuclear supernova

    E-Print Network [OSTI]

    Kushnir, Doron

    2014-01-01T23:59:59.000Z

    We demonstrate that $\\sim10$ seconds after core-collapse of a massive star, a thermonuclear explosion of the outer shells is possible for some (tuned) initial density and composition profiles, assuming the neutrinos failed to explode the star. The explosion may lead to a successful supernova, as first suggested by Burbidge, Burbidge, Fowler and Hoyle (1957). We perform a series of one-dimensional (1D) calculations of collapsing massive stars with simplified initial density profiles (similar to the results of stellar evolution calculations) and various compositions (not similar to 1D stellar evolution calculations). We assume that the neutrinos escaped with negligible effect on the outer layers, which inevitably collapse. As the shells collapse, they compress and heat up adiabatically, enhancing the rate of thermonuclear burning. In some cases, where significant shells of mixed helium and oxygen are present with pre-collapsed burning times of $\\lesssim100\\,\\textrm{s}$ ($\\approx10$ times the free-fall time), a ...

  20. NACRE II: an update of the NACRE compilation of charged-particle-induced thermonuclear reaction rates for nuclei with mass number $A < 16$

    E-Print Network [OSTI]

    Yi Xu; Kohji Takahashi; Stephane Goriely; Marcel Arnould; Masahisa Ohta; Hiroaki Utsunomiya

    2013-10-26T23:59:59.000Z

    An update of the NACRE compilation [Angulo et al., Nucl. Phys. A 656 (1999) 3] is presented. This new compilation, referred to as NACRE II, reports thermonuclear reaction rates for 34 charged-particle induced, two-body exoergic reactions on nuclides with mass number $A<16$, of which fifteen are particle-transfer reactions and the rest radiative capture reactions. When compared with NACRE, NACRE II features in particular (1) the addition to the experimental data collected in NACRE of those reported later, preferentially in the major journals of the field by early 2013, and (2) the adoption of potential models as the primary tool for extrapolation to very low energies of astrophysical $S$-factors, with a systematic evaluation of uncertainties. As in NACRE, the rates are presented in tabular form for temperatures in the $10^{6}$ $\\simeq\\leq$ T $\\leq$ $10^{10}$ K range. Along with the 'adopted' rates, their low and high limits are provided. The new rates are available in electronic form as part of the Brussels Library (BRUSLIB) of nuclear data. The NACRE II rates also supersede the previous NACRE rates in the Nuclear Network Generator (NETGEN) for astrophysics. [http://www.astro.ulb.ac.be/databases.html.

  1. Russian scientists to join round-the-world computer network ring. 28.01.2004, 21.08

    E-Print Network [OSTI]

    in order to exchange with their foreign colleagues information on thermonuclear fusion and the creation thermonuclear experimental reactor (ITER) project have an opportunity to offer technical solutions for building of ITER, Velikhov said the decision on the site for the world' s first international thermonuclear

  2. ON THE COOLING TAILS OF THERMONUCLEAR X-RAY BURSTS: THE IGR J17480-2446 LINK

    SciTech Connect (OSTI)

    Linares, M.; Chakrabarty, D. [Massachusetts Institute of Technology, Kavli Institute for Astrophysics and Space Research, Cambridge, MA 02139 (United States); Van der Klis, M. [Astronomical Institute 'Anton Pannekoek', University of Amsterdam and Center for High-Energy Astrophysics, P.O. Box 94249, 1090 GE Amsterdam (Netherlands)

    2011-06-01T23:59:59.000Z

    The neutron star transient and 11 Hz X-ray pulsar IGR J17480-2446, recently discovered in the globular cluster Terzan 5, showed unprecedented bursting activity during its 2010 October-November outburst. We analyzed all X-ray bursts detected with the Rossi X-ray Timing Explorer and find strong evidence that they all have a thermonuclear origin, despite the fact that many do not show the canonical spectral softening along the decay imprinted on type I X-ray bursts by the cooling of the neutron star photosphere. We show that the persistent-to-burst power ratio is fully consistent with the accretion-to-thermonuclear efficiency ratio along the whole outburst, as is typical for type I X-ray bursts. The burst energy, peak luminosity, and daily-averaged spectral profiles all evolve smoothly throughout the outburst, in parallel with the persistent (non-burst) luminosity. We also find that the peak-burst to persistent luminosity ratio determines whether or not cooling is present in the bursts from IGR J17480-2446, and argue that the apparent lack of cooling is due to the 'non-cooling' bursts having both a lower peak temperature and a higher non-burst (persistent) emission. We conclude that the detection of cooling along the decay is a sufficient, but not a necessary condition to identify an X-ray burst as thermonuclear. Finally, we compare these findings with X-ray bursts from other rapidly accreting neutron stars.

  3. Relics of metal-free low mass stars exploding as thermonuclear supernovae

    E-Print Network [OSTI]

    Tsujimoto, T; Tsujimoto, Takuji; Shigeyama, Toshikazu

    2006-01-01T23:59:59.000Z

    Renewed interest in the first stars that were formed in the universe has led to the discovery of extremely iron-poor stars. Since several competing scenarios exist, our understanding of the mass range that determines the observed elemental abundances remains unclear. In this study, we consider three well-studied metal-poor stars in terms of the theoretical supernovae (SNe) model. Our results suggest that the observed abundance patterns in the metal-poor star BD +80 245 and the pair of stars HD 134439/40 agree strongly with the theoretical possibility that these stars inherited their heavy element abundance patterns from SNe initiated by thermonuclear runaways in the degenerate carbon-oxygen cores of primordial asymptotic giant branch stars with \\~3.5-5 solar masses. Recent theoretical calculations have predicted that such SNe could be originated from metal-free stars in the intermediate mass range. On the other hand, intermediate mass stars containing some metals would end their lives as white dwarfs after ex...

  4. Thermonuclear explosions of Chandrasekhar-mass C+O white dwarfs

    E-Print Network [OSTI]

    M. Reinecke; W. Hillebrandt; J. C. Niemeyer

    1999-04-23T23:59:59.000Z

    First results of simulations are presented which compute the dynamical evolution of a Chandrasekhar-mass white dwarf, consisting of equal amounts of carbon and oxygen, from the onset of violent thermonuclear burning, by means of a new two-dimensional numerical code. Since in the interior of such a massive white dwarf nuclear burning progresses on microscopic scales as a sharp discontinuity, a so-called flamelet, which cannot be resolved by any numerical scheme, and since on macroscopic scales the burning front propagates due to turbulence, we make an attempt to model both effects explicitly in the framework of a finite-volume hydrodynamics code. Turbulence is included by a sub-grid model, following the spirit of large eddy simulations, and the well-localized burning front is treated by means of a level set, which allows us to compute the geometrical structure of the front more accurately than with previous methods. The only free parameters of our simulations are the location and the amount of nuclear fuel that is ignited as an initial perturbation. We find that models in which explosive carbon burning is ignited at the center remain bound by the time the front reaches low densities, where we stopped the computations because our description of combustion is no longer applicable. In contrast, off-center ignition models give rise to explosions which, however, are still too weak for typical Type Ia supernovae. Possible reasons for this rather disappointing result are discussed.

  5. On the applicability of the level set method beyond the flamelet regime in thermonuclear supernova simulations

    E-Print Network [OSTI]

    W. Schmidt

    2007-01-15T23:59:59.000Z

    In thermonuclear supernovae, intermediate mass elements are mostly produced by distributed burning provided that a deflagration to detonation transition does not set in. Apart from the two-dimensional study by Roepke & Hillebrandt (2005), very little attention has been payed so far to the correct treatment of this burning regime in numerical simulations. In this article, the physics of distributed burning is reviewed from the literature on terrestrial combustion and differences which arise from the very small Prandtl numbers encountered in degenerate matter are pointed out. Then it is shown that the level set method continues to be applicable beyond the flamelet regime as long as the width of the flame brush does not become smaller than the numerical cutoff length. Implementing this constraint with a simple parameterisation of the effect of turbulence onto the energy generation rate, the production of intermediate mass elements increases substantially compared to previous simulations, in which the burning process was stopped once the mass density dropped below 10^7 g/cm^3. Although these results depend on the chosen numerical resolution, an improvement of the constraints on the the total mass of burning products in the pure deflagration scenario can be achieved.

  6. Rotational effects in thermonuclear Type I Bursts: equatorial crossing and directionality of flame spreading

    E-Print Network [OSTI]

    Cavecchi, Yuri; Levin, Yuri; Braithwaite, Jonathan

    2014-01-01T23:59:59.000Z

    In a previous study on thermonuclear (Type I) Bursts on accreting neutron stars we addressed and demonstrated the importance of the effects of rotation, through the Coriolis force, on the propagation of the burning flame. However, that study only analysed cases of longitudinal propagation, where the Coriolis force coefficient $2\\Omega\\cos\\theta$ was constant. In this paper, we study the effects of rotation on propagation in the meridional (latitudinal) direction, where the Coriolis force changes from its maximum at the poles to zero at the equator. We find that the zero Coriolis force at the equator, while affecting the structure of the flame, does not prevent its propagation from one hemisphere to another. We also observe structural differences between the flame propagating towards the equator and that propagating towards the pole, the second being faster. In the light of the recent discovery of the low spin frequency of burster IGR~J17480-2446 rotating at 11 Hz (for which Coriolis effects should be negligib...

  7. Evidence for enhanced persistent emission during sub-Eddington thermonuclear bursts

    E-Print Network [OSTI]

    Worpel, Hauke; Price, Daniel J

    2015-01-01T23:59:59.000Z

    The standard approach for time-resolved X-ray spectral analysis of thermonuclear bursts involves subtraction of the pre-burst emission as background. This approach implicitly assumes that the persistent flux remains constant throughout the burst. We reanalyzed 332 photospheric radius expansion bursts observed from 40 sources by the Rossi X-ray Timing Explorer, introducing a multiplicative factor $f_a$ to the persistent emission contribution in our spectral fits. We found that for the majority of spectra the best-fit value of $f_a$ is significantly greater than 1, suggesting that the persistent emission typically increases during a burst. Elevated $f_a$ values were not found solely during the radius expansion interval of the burst, but were also measured in the cooling tail. The modified model results in a lower average value of the $\\chi^2$ fit statistic, indicating superior spectral fits, but not yet to the level of formal statistical consistency for all the spectra. We interpret the elevated $f_a$ values as...

  8. Thermonuclear reaction rate of 18O(p,gamma)19F

    E-Print Network [OSTI]

    M. Q. Buckner; C. Iliadis; J. M. Cesaratto; C. Howard; T. B. Clegg; A. E. Champagne; S. Daigle

    2012-12-05T23:59:59.000Z

    For stars between 0.8-8.0 solar masses, nucleosynthesis enters its final phase during the asymptotic giant branch (AGB) stage. During this evolutionary period, grain condensation occurs in the stellar atmosphere, and the star experiences significant mass loss. The production of presolar grains can often be attributed to this unique stellar environment. A subset of presolar oxide grains features dramatic 18O depletion that cannot be explained by the standard AGB star burning stages and dredge-up models. An extra mixing process, referred to as "cool bottom processing" (CBP), was proposed for low-mass AGB stars. The 18O depletion observed within certain stellar environments and within presolar grain samples may result from the 18O+p processes during CBP. We report here on a study of the 18O(p,gamma)19F reaction at low energies. Based on our new results, we found that the resonance at Er = 95 keV (lab) has a negligible affect on the reaction rate at the temperatures associated with CBP. We also determined that the direct capture S-factor is almost a factor of 2 lower than the previously recommended value at low energies. An improved thermonuclear reaction rate for 18O(p,gamma)19F is presented.

  9. The progenitors of core-collapse supernovae suggest thermonuclear origin for the explosions

    E-Print Network [OSTI]

    Kushnir, Doron

    2015-01-01T23:59:59.000Z

    Core-collapse supernovae (CCSNe) are the explosions of massive stars following the collapse of the stars' iron cores. Poznanski (2013) has recently suggested an observational correlation between the ejecta velocities and the inferred masses of the red supergiant progenitors of type II-P explosions, which implies that the kinetic energy of the ejecta ($E_{\\textrm{kin}}$) increases with the mass of the progenitor. I point out that the same conclusion can be reached from the model-free observed correlation between the ejected $^{56}$Ni masses ($M_{\\textrm{Ni}}$) and the luminosities of the progenitors for type II supernovae, which was reported by Fraser et al. (2011). This correlation is in an agreement with the predictions of the collapse-induced thermonuclear explosions (CITE) for CCSNe and in a possible contradiction with the predictions of the neutrino mechanism. I show that a correlation between $M_{\\textrm{Ni}}$ and $E_{\\textrm{kin}}$ holds for all types of CCSNe (including type Ibc). This correlation sugg...

  10. Evidence of thermonuclear flame spreading on neutron stars from burst rise oscillations

    E-Print Network [OSTI]

    Chakraborty, Manoneeta

    2014-01-01T23:59:59.000Z

    Burst oscillations during the rising phases of thermonuclear X-ray bursts are usually believed to originate from flame spreading on the neutron star surface. However, the decrease of fractional oscillation amplitude with rise time, which provides a main observational support for the flame spreading model, have so far been reported from only a few bursts. Moreover, the non-detection and intermittent detections of rise oscillations from many bursts are not yet understood considering the flame spreading scenario. Here, we report the decreasing trend of fractional oscillation amplitude from an extensive analysis of a large sample of Rossi X-ray Timing Explorer Proportional Counter Array bursts from ten neutron star low-mass X-ray binaries. This trend is 99.99% significant for the best case, which provides, to the best of our knowledge, by far the strongest evidence of such trend. Moreover, it is important to note that an opposite trend is not found from any of the bursts. The concave shape of the fractional ampli...

  11. Screened thermonuclear reactions and predictive stellar evolution of detached double-lined eclipsing binaries

    E-Print Network [OSTI]

    Theodore Liolios; Theocharis Kosmas

    2005-07-06T23:59:59.000Z

    The low energy fusion cross sections of charged-particle nuclear reactions (and the respective reaction rates) in stellar plasmas are enhanced due to plasma screening effects. We study the impact of those effects on predictive stellar evolution simulations for detached double-lined eclipsing binaries. We follow the evolution of binary systems (pre-main sequence or main sequence stars) with precisely determined radii and masses from 1.1Mo to 23Mo (from their birth until their present state). The results indicate that all the discrepancies between the screened and unscreened models (in terms of luminosity, stellar radius, and effective temperature) are within the observational uncertainties. Moreover, no nucleosynthetic or compositional variation was found due to screening corrections. Therefore all thermonuclear screening effects on the charged-particle nuclear reactions that occur in the binary stars considered in this work (from their birth until their present state) can be totally disregarded. In other words, all relevant charged-particle nuclear reactions can be safely assumed to take place in a vacuum, thus simplifying and accelerating the simulation processes.

  12. Charged-Particle Thermonuclear Reaction Rates: I. Monte Carlo Method and Statistical Distributions

    E-Print Network [OSTI]

    Richard Longland; Christian Iliadis; Art Champagne; Joe Newton; Claudio Ugalde; Alain Coc; Ryan Fitzgerald

    2010-04-23T23:59:59.000Z

    A method based on Monte Carlo techniques is presented for evaluating thermonuclear reaction rates. We begin by reviewing commonly applied procedures and point out that reaction rates that have been reported up to now in the literature have no rigorous statistical meaning. Subsequently, we associate each nuclear physics quantity entering in the calculation of reaction rates with a specific probability density function, including Gaussian, lognormal and chi-squared distributions. Based on these probability density functions the total reaction rate is randomly sampled many times until the required statistical precision is achieved. This procedure results in a median (Monte Carlo) rate which agrees under certain conditions with the commonly reported recommended "classical" rate. In addition, we present at each temperature a low rate and a high rate, corresponding to the 0.16 and 0.84 quantiles of the cumulative reaction rate distribution. These quantities are in general different from the statistically meaningless "minimum" (or "lower limit") and "maximum" (or "upper limit") reaction rates which are commonly reported. Furthermore, we approximate the output reaction rate probability density function by a lognormal distribution and present, at each temperature, the lognormal parameters miu and sigma. The values of these quantities will be crucial for future Monte Carlo nucleosynthesis studies. Our new reaction rates, appropriate for bare nuclei in the laboratory, are tabulated in the second paper of this series (Paper II). The nuclear physics input used to derive our reaction rates is presented in the third paper of this series (Paper III). In the fourth paper of this series (Paper IV) we compare our new reaction rates to previous results.

  13. THE FERMI-GBM X-RAY BURST MONITOR: THERMONUCLEAR BURSTS FROM 4U 0614+09

    SciTech Connect (OSTI)

    Linares, M.; Chakrabarty, D. [Massachusetts Institute of Technology, Kavli Institute for Astrophysics and Space Research, Cambridge, MA 02139 (United States); Connaughton, V.; Bhat, P. N.; Briggs, M. S.; Preece, R. [CSPAR and Physics Department, University of Alabama in Huntsville, Huntsville, AL 35899 (United States); Jenke, P.; Kouveliotou, C.; Wilson-Hodge, C. A. [Space Science Office, VP62, NASA/Marshall Space Flight Center, Huntsville, AL 35812 (United States); Van der Horst, A. J. [Astronomical Institute 'Anton Pannekoek', University of Amsterdam, NL-1090-GE Amsterdam (Netherlands); Camero-Arranz, A.; Finger, M.; Paciesas, W. S. [Universities Space Research Association, Huntsville, AL 35805 (United States); Beklen, E. [Physics Department, Suleyman Demirel University, 32260 Isparta (Turkey); Von Kienlin, A. [Max Planck Institute for Extraterrestrial Physics, Giessenbachstrasse, Postfach 1312, D-85748 Garching (Germany)

    2012-12-01T23:59:59.000Z

    Thermonuclear bursts from slowly accreting neutron stars (NSs) have proven difficult to detect, yet they are potential probes of the thermal properties of the NS interior. During the first year of a systematic all-sky search for X-ray bursts using the Gamma-ray Burst Monitor aboard the Fermi Gamma-ray Space Telescope we have detected 15 thermonuclear bursts from the NS low-mass X-ray binary 4U 0614+09 when it was accreting at nearly 1% of the Eddington limit. We measured an average burst recurrence time of 12 {+-} 3 days (68% confidence interval) between 2010 March and 2011 March, classified all bursts as normal duration bursts and placed a lower limit on the recurrence time of long/intermediate bursts of 62 days (95% confidence level). We discuss how observations of thermonuclear bursts in the hard X-ray band compare to pointed soft X-ray observations and quantify such bandpass effects on measurements of burst radiated energy and duration. We put our results for 4U 0614+09 in the context of other bursters and briefly discuss the constraints on ignition models. Interestingly, we find that the burst energies in 4U 0614+09 are on average between those of normal duration bursts and those measured in long/intermediate bursts. Such a continuous distribution in burst energy provides a new observational link between normal and long/intermediate bursts. We suggest that the apparent bimodal distribution that defined normal and long/intermediate duration bursts during the last decade could be due to an observational bias toward detecting only the longest and most energetic bursts from slowly accreting NSs.

  14. IOP PUBLISHING and INTERNATIONAL ATOMIC ENERGY AGENCY NUCLEAR FUSION Nucl. Fusion 50 (2010) 014002 (10pp) doi:10.1088/0029-5515/50/1/014002

    E-Print Network [OSTI]

    2010-01-01T23:59:59.000Z

    Harnessing the energy of thermonuclear fusion reactions is one of the greatest challenges of our time. FusionIOP PUBLISHING and INTERNATIONAL ATOMIC ENERGY AGENCY NUCLEAR FUSION Nucl. Fusion 50 (2010) 014002 (10pp) doi:10.1088/0029-5515/50/1/014002 ITER on the road to fusion energy Kaname Ikeda Director

  15. The Effects of Variations in Nuclear Interactions on Nucleosynthesis in Thermonuclear Supernovae

    E-Print Network [OSTI]

    Anuj Parikh; Jordi Jose; Ivo R. Seitenzahl; Friedrich K. Roepke

    2013-06-25T23:59:59.000Z

    The impact of nuclear physics uncertainties on nucleosynthesis in thermonuclear supernovae has not been fully explored using comprehensive and systematic studies with multiple models. To better constrain predictions of yields from these phenomena, we have performed a sensitivity study by post-processing thermodynamic histories from two different hydrodynamic, Chandrasekhar-mass explosion models. We have individually varied all input reaction and, for the first time, weak interaction rates by a factor of ten and compared the yields in each case to yields using standard rates. Of the 2305 nuclear reactions in our network, we find that the rates of only 53 reactions affect the yield of any species with an abundance of at least 10^-8 M_sun by at least a factor of two, in either model. The rates of the 12C(a,g), 12C+12C, 20Ne(a,p), 20Ne(a,g) and 30Si(p,g) reactions are among those that modify the most yields when varied by a factor of ten. From the individual variation of 658 weak interaction rates in our network by a factor of ten, only the stellar 28Si(b+)28Al, 32S(b+)32P and 36Ar(b+)36Cl rates significantly affect the yields of species in a model. Additional tests reveal that reaction rate changes over temperatures T > 1.5 GK have the greatest impact, and that ratios of radionuclides that may be used as explosion diagnostics change by a factor of less than two from the variation of individual rates by a factor of 10. Nucleosynthesis in the two adopted models is relatively robust to variations in individual nuclear reaction and weak interaction rates. Laboratory measurements of a limited number of reactions would help to further constrain predictions. As well, we confirm the need for a consistent treatment for relevant stellar weak interaction rates since simultaneous variation of these rates (as opposed to individual variation) has a significant effect on yields in our models.

  16. INTERNATIONAL International Internship for

    E-Print Network [OSTI]

    Napier, Terrence

    OFFICE OF INTERNATIONAL AFFAIRS International Internship for Global Leadership Program Student Portugal ­ Laura Sieger Ukraine ­ Mary Brune 2012 Internship Locations #12;Dear Friends and Colleagues of Lehigh University: The International Internship for Global Leadership Program provides Lehigh students

  17. On the Frequency Evolution of X-ray Brightness Oscillations During Thermonuclear X-ray Bursts: Evidence for Coherent Oscillations

    E-Print Network [OSTI]

    Tod E. Strohmayer; Craig B. Markwardt

    1999-03-03T23:59:59.000Z

    We investigate the time dependence of the frequency of X-ray brightness oscillations during thermonuclear bursts from several neutron star low mass X-ray binaries. We find that the oscillation frequencies in the cooling tails of X-ray bursts from 4U 1702-429 and 4U 1728-34 are well described by an exponential "chirp" model. With this model we demonstrate that the pulse trains in the cooling tails of many bursts are highly phase coherent, having oscillation quality factors as high as Q ~ 4000. We use this model of the frequency evolution to search sensitively for significant power at the harmonics and first sub-harmonic of the 330 and 363 Hz signals in bursts from 4U 1702-429 and 4U 1728-34, respectively, but find not evidence for significant power at any harmonic or the sub-harmonic. We argue that the high coherence favors stellar rotation as the source of the oscillations. We briefly discuss the frequency evolution in terms of rotational motion of an angular momentum conserving thermonuclear shell. we discuss how the limits on harmonic content can be used to infer properties of the neutron star.

  18. JOURNAL DE PHYSIQUE Colloque C1, supplkment au no2, Tome 40,fkvr~er1979, page C1-73 ATOMIC, IONIC AND MOLECULAR DATA IN THERMO-NUCLEAR FUSION RESEARCH

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    AND MOLECULAR DATA IN THERMO-NUCLEAR FUSION RESEARCH H.W. Drawin Association EURATOM-CEA DQpartement de Physique section deals with molecular data which are of interest in thermo-nuclear fusion research. 1. INTRODUCTION In order to achieve controlled thermo- nuclear fusion of deuterium and tritium one needs both high

  19. PPPL3171 Preprint Date: May 1996, UC421, 423, 427 Simulations of alpha particle ripple loss from the

    E-Print Network [OSTI]

    International Thermonuclear Experimental Reactor (ITER) [Plasma Physics and Controlled Nuclear Fusion Research from the International Thermonuclear Experimental Reactor M. H. Redi, R. V. Budny, D. C. McCune, C. O of the ripple minimum for D shaped ripple contours. In contrast to alpha loss simulations for the Tokamak Fusion

  20. U.S. to join research effort for fusion power Friday, January 31, 2003 file:///Macintosh%20HD/Desktop%20Folder/ITER%20Negotiations/MSNBC/

    E-Print Network [OSTI]

    , the International Thermonuclear Experimental Reactor, is a fusion research project that is already a joint operationU.S. to join research effort for fusion power Friday, January 31, 2003 file:///Macintosh%20HD view of the proposed International Thermonuclear Experimental Reactor, with a central containment

  1. PPPL-3171 -Preprint Date: May 1996, UC-421, 423, 427 Simulations of alpha particle ripple loss from the

    E-Print Network [OSTI]

    Thermonuclear Experimental Reactor (ITER) [Plasma Physics and Controlled Nuclear Fusion Research (International from the International Thermonuclear Experimental Reactor M. H. Redi, R. V. Budny, D. C. McCune, C. O for D shaped ripple contours. In contrast to alpha loss simulations for the Tokamak Fusion Test Reactor

  2. Concept of a thermonuclear reactor based on gravity retention of high-temperature plasma

    E-Print Network [OSTI]

    S. I. Fisenko; I. S. Fisenko

    2007-05-27T23:59:59.000Z

    In the present paper the realization of the obtained results in relation to the dense high- temperature plasma of multivalent ions including experimental data interpretation is discussed.

  3. 4/20/14 12:35 PMSenators Request GAO Investigation of Costs at Experimental Fusion React...tems -Newsroom -U.S. Senate Committee on Energy and Natural Resources Page 1 of 2http://www.energy.senate.gov/public/index.cfm/featured-items?ID=854ad0a0-fe2a-4a04-

    E-Print Network [OSTI]

    Thermonuclear Experimental Reactor and its effect on U.S. fusion programs. Senators Ron Wyden, D-Ore., Lisa4/20/14 12:35 PMSenators Request GAO Investigation of Costs at Experimental Fusion React.S. fusion energy science programs and user facilities have, and may continue to be, cut to pay

  4. IOP PUBLISHING and INTERNATIONAL ATOMIC ENERGY AGENCY NUCLEAR FUSION Nucl. Fusion 50 (2010) 014003 (8pp) doi:10.1088/0029-5515/50/1/014003

    E-Print Network [OSTI]

    2010-01-01T23:59:59.000Z

    . They formulated the principles of magnetic confinement of high temperature plasmas, that would allow the development of a thermonuclear reactor. Following this, experimental research on plasma initiation and heating centre, formulated the initial principles of magnetic confinement of high temperature plasma

  5. On the Effect of Explosive Thermonuclear Burning on the Accreted Envelopes of White Dwarfs in Cataclysmic Variables

    E-Print Network [OSTI]

    Sion, Edward M

    2014-01-01T23:59:59.000Z

    The detection of heavy elements at suprasolar abundances in the atmospheres of some accreting white dwarfs in cataclysmic variables, coupled with the high temperatures needed to produce these elements requires explosive thermonuclear burning. The central temperatures of any formerly more massive secondary stars in CVs undergoing hydrostatic CNO burning are far too low to produce these elements. Evidence is presented that at least some cataclysmic variables contain donor secondaries that have been contaminated by repeated novae ejecta and are transferring this material back to the white dwarf. This scenario does not exclude the channel in which formerly more massive donor stars underwent CNO processing in ystems that underwent thermal timescale mass transfer. Implications for the progenitors of CVs are discussed.

  6. Model based multivariable controller for large scale compression stations. Design and experimental validation on the LHC 18KW cryorefrigerator

    SciTech Connect (OSTI)

    Bonne, François; Bonnay, Patrick [INAC, SBT, UMR-E 9004 CEA/UJF-Grenoble, 17 rue des Martyrs, 38054 Grenoble (France); Alamir, Mazen [Gipsa-Lab, Control Systems Department, CNRS-University of Grenoble, 11, rue des Mathématiques, BP 46, 38402 Saint Martin d'Hères (France); Bradu, Benjamin [CERN, CH-1211 Genève 23 (Switzerland)

    2014-01-29T23:59:59.000Z

    In this paper, a multivariable model-based non-linear controller for Warm Compression Stations (WCS) is proposed. The strategy is to replace all the PID loops controlling the WCS with an optimally designed model-based multivariable loop. This new strategy leads to high stability and fast disturbance rejection such as those induced by a turbine or a compressor stop, a key-aspect in the case of large scale cryogenic refrigeration. The proposed control scheme can be used to have precise control of every pressure in normal operation or to stabilize and control the cryoplant under high variation of thermal loads (such as a pulsed heat load expected to take place in future fusion reactors such as those expected in the cryogenic cooling systems of the International Thermonuclear Experimental Reactor ITER or the Japan Torus-60 Super Advanced fusion experiment JT-60SA). The paper details how to set the WCS model up to synthesize the Linear Quadratic Optimal feedback gain and how to use it. After preliminary tuning at CEA-Grenoble on the 400W@1.8K helium test facility, the controller has been implemented on a Schneider PLC and fully tested first on the CERN's real-time simulator. Then, it was experimentally validated on a real CERN cryoplant. The efficiency of the solution is experimentally assessed using a reasonable operating scenario of start and stop of compressors and cryogenic turbines. This work is partially supported through the European Fusion Development Agreement (EFDA) Goal Oriented Training Program, task agreement WP10-GOT-GIRO.

  7. Results of an international study on a high-volume plasma-based neutron source for fusion blanket development

    SciTech Connect (OSTI)

    Abdou, M.A.; Ying, A. [Univ. of California, Los Angeles, CA (United States); Berk, S.E. [Department of Energy, Washington, DC (United States)] [and others

    1996-01-01T23:59:59.000Z

    A number of scenarios for fusion facilities were evaluated using a cost/benefit/risk analysis approach. Blanket tests in the International Thermonuclear Experimental Reactor (ITER) alone with a fluence of 1 MW.yr/m{sup 2} can address most of the needs for concept verification, but it cannot adequately address the blanket component reliability growth/demonstration testing requirements. An effective path to fusion DEMO is suggested. It involves two parallel facilities: (a) ITER to provide data on plasma performance, plasma support technology, and system integration and (b) a high-volume plasma-based neutron source (HVPNS) dedicated to testing, developing, and qualifying fusion nuclear components and material combinations for DEMO. For HVPNS to be attractive and cost effective, its capital cost must be significantly lower than ITER, and it should have low fusion power (nearly 150 MW). Exploratory studies indicate the presence of a design window with a highly driven plasma. A testing and development strategy that includes HVPNS would decisively reduce the high risk of initial DEMO operation with a poor blanket system availability and would make it possible - if operated parallel to the ITER basic performance phase - to meet the goal of DEMO operation by the year 2025. Such a scenario with HVPNS parallel to ITER provides substantial savings in the overall R&D cost toward DEMO compared with an ITER-alone strategy. 75 refs., 13 figs., 31 tabs.

  8. Experimental verification of effects of barrier dopings on the internal electric fields and the band structure in InGaN/GaN light emitting diodes

    SciTech Connect (OSTI)

    Song, Jung-Hoon; Kim, Tae-Soo; Park, Ki-Nam; Lee, Jin-Gyu [Department of Physics, Kongju National University, Kongju, Chungnam 314-701 (Korea, Republic of); Hong, Soon-Ku, E-mail: soonku@cnu.ac.kr [Department of Advanced Materials Engineering, Chungnam National University, Daejeon 305-764 (Korea, Republic of); Cho, Sung-Royng; Lee, Seogwoo; Whan Cho, Meoung [Wasvesquare Co., Inc., Yongin, Gyeonggi 449-863 (Korea, Republic of)

    2014-03-24T23:59:59.000Z

    We experimentally clarify the effects of barrier dopings on the polarization induced electric fields and the band structure in InGaN/GaN blue light emitting diodes. Both effects were independently verified by using electric field modulated reflectance and capacitance-voltage measurement. It is shown that the Si barrier doping does reduce the polarization induced electric field in the quantum wells. But the benefit of Si-doping is nullified by modification of the band structure and depletion process. With increased number of doped barriers, smaller number of quantum wells remains in the depletion region at the onset of the diffusion process, which can reduce the effective active volume and enhance the electron overflow.

  9. Two days of negotiations in

    E-Print Network [OSTI]

    France or Japan would host the revolutionary International Thermonuclear Experimental Reactor (ITER to secure an agreement on whether France or Japan would host the revolutionary International Thermonuclear, deputy director of Japan's Office of Fusion Energy, told AFP. "What we have proposed is that the host

  10. The thermonuclear rate for the 19F(a,p)22Ne reaction at stellar temperatures

    E-Print Network [OSTI]

    Claudio Ugalde; Richard Azuma; Aaron Couture; Joachim Görres; Hye-Young Lee; Edward Stech; Elizabeth Strandberg; Wanpeng Tan; Michael Wiescher

    2008-03-04T23:59:59.000Z

    The $^{19}$F($\\alpha$,p)$^{22}$Ne reaction is considered to be one of the main sources of fluorine depletion in AGB and Wolf-Rayet stars. The reaction rate still retains large uncertainties due to the lack of experimental studies available. In this work the yields for both exit channels to the ground state and first excited state of $^{22}$Ne have been measured and several previously unobserved resonances have been found in the energy range E$_{lab}$=792-1993 keV. The level parameters have been determined through a detailed R-matrix analysis of the reaction data and a new reaction rate is provided on the basis of the available experimental information.

  11. ORNL Environmental Monitoring Programs 5-1 5. ORNL Environmental Monitoring Programs

    E-Print Network [OSTI]

    Pennycook, Steve

    future includes hosting the U.S. project office for the International Thermonuclear Experimental Reactor international fusion experiment and the Office of Science-sponsored Bioenergy Science Center. 5.1 Description

  12. TB, AP, UK, JPhysB/330302, 29/12/2009 IOP PUBLISHING JOURNAL OF PHYSICS B: ATOMIC, MOLECULAR AND OPTICAL PHYSICS

    E-Print Network [OSTI]

    Johnson, Walter R.

    Thermonuclear Experimental Reactor. (Some figures in this article are in colour only in the electronic version for future experiments at the International Thermonuclear Experimental Reactor (ITER). The effect, spectroscopy of highly charged tungsten ions relevant to fusion plasmas was recently discussed by Biedermann et

  13. The longest thermonuclear X-ray burst ever observed? (A BeppoSAX Wide Field Camera observation of 4U 1735-44)

    E-Print Network [OSTI]

    R. Cornelisse; J. Heise; E. Kuulkers; F. Verbunt; J. J. M. in 't Zand

    2000-03-30T23:59:59.000Z

    A long flux enhancement, with an exponential decay time of 86 min, is detected in 4U 1735-44 with the BeppoSAX Wide Field Cameras. We argue that this is a type-I X-ray burst, making it the longest such burst ever observed. Current theories for thermonuclear bursts predict shorter and more frequent bursts for the observed persistent accretion rate.

  14. International Policy International Development

    E-Print Network [OSTI]

    Watson, Andrew

    Research Strategy 2006-2009 International Policy Energy Adaptation International Development Coasts Change Research. Our strategy builds upon our previous work on integrated assessment, energy, adaptation of time. In this spirit, the Centre reconfirms its vision statement: "The Tyndall Centre is the UK network

  15. The Long Term Stability of Oscillations During Thermonuclear X-ray Bursts: Constraining the Binary X-ray Mass Function

    E-Print Network [OSTI]

    Tod E. Strohmayer; William Zhang; Jean H. Swank; Iosif Lapidus

    1998-06-18T23:59:59.000Z

    We report on the long term stability of the millisecond oscillations observed with the Rossi X-ray Timing Explorer (RXTE) during thermonuclear X-ray bursts from the low mass X-ray binaries (LMXB) 4U 1728-34 and 4U 1636-53. We show that bursts from 4U 1728-34 spanning more than 1.5 years have observed asymptotic oscillation periods which are within 0.2 microsec. of each other, well within the magnitude which could be produced by the orbital motion of the neutron star in a typical LMXB. This stability implies a timescale to change the oscillation period of > 23,000 years, suggesting a highly stable process such as stellar rotation as the oscillation mechanism. We show that period offsets in three distinct bursts from 4U 1636-53 can be plausibly interpreted as due to orbital motion of the neutron star in this 3.8 hour binary system. We discuss the constraints on the mass function which can in principle be derived using this technique.

  16. Systematic variation in the apparent burning area of thermonuclear bursts and its implication for neutron star radius measurement

    E-Print Network [OSTI]

    Sudip Bhattacharyya; M. Coleman Miller; Duncan K. Galloway

    2009-08-28T23:59:59.000Z

    Precision measurements of neutron star radii can provide a powerful probe of the properties of cold matter beyond nuclear density. Beginning in the late 1970s it was proposed that the radius could be obtained from the apparent or inferred emitting area during the decay portions of thermonuclear (type I) X-ray bursts. However, this apparent area is generally not constant, preventing reliable measurement of the source radius. Here we report for the first time a correlation between the variation of the inferred area and the burst properties, measured in a sample of almost 900 bursts from 43 sources. We found that the rate of change of the inferred area during decay is anticorrelated with the burst decay duration. A Spearman rank correlation test shows that this relation is significant at the <10^{-45} level for our entire sample, and at the 7x10^{-37} level for the 625 bursts without photospheric radius expansion. This anticorrelation is also highly significant for individual sources exhibiting a wide range of burst durations, such as 4U 1636-536 and Aql X-1. We suggest that variations in the colour factor, which relates the colour temperature resulted from the scattering in the neutron star atmosphere to the effective temperature of the burning layer, may explain the correlation. This in turn implies significant variations in the composition of the atmosphere between bursts with long and short durations.

  17. Charged-Particle Thermonuclear Reaction Rates: II. Tables and Graphs of Reaction Rates and Probability Density Functions

    E-Print Network [OSTI]

    Christian Iliadis; Richard Longland; Art Champagne; Alain Coc; Ryan Fitzgerald

    2010-04-23T23:59:59.000Z

    Numerical values of charged-particle thermonuclear reaction rates for nuclei in the A=14 to 40 region are tabulated. The results are obtained using a method, based on Monte Carlo techniques, that has been described in the preceding paper of this series (Paper I). We present a low rate, median rate and high rate which correspond to the 0.16, 0.50 and 0.84 quantiles, respectively, of the cumulative reaction rate distribution. The meaning of these quantities is in general different from the commonly reported, but statistically meaningless expressions, "lower limit", "nominal value" and "upper limit" of the total reaction rate. In addition, we approximate the Monte Carlo probability density function of the total reaction rate by a lognormal distribution and tabulate the lognormal parameters {\\mu} and {\\sigma} at each temperature. We also provide a quantitative measure (Anderson-Darling test statistic) for the reliability of the lognormal approximation. The user can implement the approximate lognormal reaction rate probability density functions directly in a stellar model code for studies of stellar energy generation and nucleosynthesis. For each reaction, the Monte Carlo reaction rate probability density functions, together with their lognormal approximations, are displayed graphically for selected temperatures in order to provide a visual impression. Our new reaction rates are appropriate for bare nuclei in the laboratory. The nuclear physics input used to derive our reaction rates is presented in the subsequent paper of this series (Paper III). In the fourth paper of this series (Paper IV) we compare our new reaction rates to previous results.

  18. Investigation of thermonuclear $^{18}$Ne($?$,$p$)$^{21}$Na rate via resonant elastic scattering of $^{21}$Na+$p$

    E-Print Network [OSTI]

    L. Y. Zhang; J. J. He; A. Parikh; S. W. Xu; H. Yamaguchi; D. Kahl; S. Kubono; P. Mohr; J. Hu; P. Ma; S. Z. Chen; Y. Wakabayashi; H. W. Wang; W. D. Tian; R. F. Chen; B. Guo; T. Hashimoto; Y. Togano; S. Hayakawa; T. Teranishi; N. Iwasa; T. Yamada; T. Komatsubara; Y. H. Zhang; X. H. Zhou

    2014-03-19T23:59:59.000Z

    The $^{18}$Ne($\\alpha$,$p$)$^{21}$Na reaction is thought to be one of the key breakout reactions from the hot CNO cycles to the rp-process in type I x-ray bursts. In this work, the resonant properties of the compound nucleus $^{22}$Mg have been investigated by measuring the resonant elastic scattering of $^{21}$Na+$p$. An 89 MeV $^{21}$Na radioactive beam delivered from the CNS Radioactive Ion Beam Separator bombarded an 8.8 mg/cm$^2$ thick polyethylene (CH$_{2}$)$_{n}$ target. The $^{21}$Na beam intensity was about 2$\\times$10$^{5}$ pps, with a purity of about 70% on target. The recoiled protons were measured at the center-of-mass scattering angles of $\\theta_{c.m.}$$\\approx$175.2${^\\circ}$, 152.2${^\\circ}$, and 150.5${^\\circ}$ by three sets of $\\Delta E$-$E$ telescopes, respectively. The excitation function was obtained with the thick-target method over energies $E_x$($^{22}$Mg)=5.5--9.2 MeV. In total, 23 states above the proton-threshold in $^{22}$Mg were observed, and their resonant parameters were determined via an $R$-matrix analysis of the excitation functions. We have made several new $J^{\\pi}$ assignments and confirmed some tentative assignments made in previous work. The thermonuclear $^{18}$Ne($\\alpha$,$p$)$^{21}$Na rate has been recalculated based on our recommended spin-parity assignments. The astrophysical impact of our new rate has been investigated through one-zone postprocessing x-ray burst calculations. We find that the $^{18}$Ne($\\alpha$,$p$)$^{21}$Na rate significantly affects the peak nuclear energy generation rate, reaction fluxes, as well as the onset temperature of this breakout reaction in these astrophysical phenomena.

  19. Sandia National Laboratories: International Tokamak Experimental...

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

    Analysis, Systems Engineering Sandian Dean Buchenauer (in Sandia's Hydrogen and Metallurgy Science Dept.) and Professor David Q. Hwang (UC Davis, School of Engineering) will...

  20. International Collaborations on Engineered Barrier Systems: Experimental

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels DataDepartment of Energy Your Density Isn't YourTransport(FactDepartment of EnergyIndustry15Among Statesfor a Smart Grid (JulySupply

  1. Method and system to directly produce electrical power within the lithium blanket region of a magnetically confined, deuterium-tritium (DT) fueled, thermonuclear fusion reactor

    DOE Patents [OSTI]

    Woolley, Robert D. (Belle Mead, NJ)

    1999-01-01T23:59:59.000Z

    A method for integrating liquid metal magnetohydrodynamic power generation with fusion blanket technology to produce electrical power from a thermonuclear fusion reactor located within a confining magnetic field and within a toroidal structure. A hot liquid metal flows from a liquid metal blanket region into a pump duct of an electromagnetic pump which moves the liquid metal to a mixer where a gas of predetermined pressure is mixed with the pressurized liquid metal to form a Froth mixture. Electrical power is generated by flowing the Froth mixture between electrodes in a generator duct. When the Froth mixture exits the generator the gas is separated from the liquid metal and both are recycled.

  2. Deadlock in ITER talks must end Tatsuo Nakajima Yomiuri Shimbun Staff Writer

    E-Print Network [OSTI]

    Japan and the European Union over where to construct the International Thermonuclear Experimental flights home, leaving before those in attendance were able to schedule the next meeting. A thermonuclear fusion, which is more efficient than nuclear fission reactors. In what will be the world's first

  3. Seminar 1b-1.letnik, II.stopnja Deuterium depth profiling with

    E-Print Network [OSTI]

    ?umer, Slobodan

    of most critical issues in the construction of thermonuclear reactor based on magnetic confiment of the deuterium-tritium operation of International Thermonuclear Experimental Reactor (ITER). ITER walls-facing materials in nuclear fusion research resulted in an increasing interest in quantitative profiling

  4. ITER site contest counts down Junichi Miura

    E-Print Network [OSTI]

    Thermonuclear Experimental Reactor (ITER), an international project to use nuclear fusion energy for electric on a site for the project. The ITER project envisions using thermonuclear fusion to generate huge amounts heavy hydrogen and tritium used for fuel in the fusion reaction are heated in a vacuum receptacle at 100

  5. Doubts Rise Over the Great Nuclear Promise Julio Godoy

    E-Print Network [OSTI]

    that a thermonuclear reactor poses three technical problems: production of the elements to undergo fusion (deuterium over a decision to base the International Thermonuclear Experimental Reactor (ITER) in France seems to introduce new nuclear technology. It will seek a nuclear fusion of two hydrogen isotopes (deuterium which

  6. Experimental Study of Pellet Delivery to the ITER Inner Wall through a Curved Guide Tube at Steady-State Pressure

    SciTech Connect (OSTI)

    Combs, Stephen Kirk [ORNL; Baylor, Larry R [ORNL; Caughman, John B [ORNL; Fehling, Dan T [ORNL; Foust, Charles R [ORNL; Maruyama, S. [ITER International Team, Garching, Germany; McGill, James M [ORNL; Rasmussen, David A [ORNL

    2006-01-01T23:59:59.000Z

    Injection of solid hydrogen pellets from the magnetic high-field side will be the primary technique for depositing fuel particles into the core of International Thermonuclear Experimental Reactor (ITER) burning plasmas. This injection scheme will require the use of a curved guide tube to route the pellets from the acceleration device, under the divertor, and to the inside wall launch location. In an initial series of pellet tests in support of ITER, single 5.3-mm-diam cylindrical D2 pellets were shot through a mock-up of the planned ITER curved guide tube. Those data showed that the pellet speed had to be limited to ?300 m/s for reliable delivery of intact pellets. Also, microwave cavity mass detectors located upstream and downstream of the test tube indicated that ?10% of the pellet mass was lost in the guide tube at 300 m/s. The tube base pressure for that test series was ?10-4 torr. However, for steady-state pellet fueling on ITER, the guide tube will operate at an elevated pressure due to the pellet erosion in the tube. Assuming the present design values for ITER pellet fueling rates/vacuum pumping and a 10% pellet mass loss during flight in the tube, calculations suggest a steadystate operating pressure in the range of 10-20 torr. Thus, experiments to ascertain the pellet integrity and mass loss under these conditions have been carried out. Also, some limited test data were collected at a tube pressure of ?100 torr. No significant detrimental effects have been observed at the higher tube pressures. The new test results are presented and compared to the baseline data previously reported.

  7. On Thermonuclear Reaction Rates

    E-Print Network [OSTI]

    H. J. Haubold; A. M. Mathai

    1996-12-02T23:59:59.000Z

    Nuclear reactions govern major aspects of the chemical evolution od galaxies and stars. Analytic study of the reaction rates and reaction probability integrals is attempted here. Exact expressions for the reaction rates and reaction probability integrals for nuclear reactions in the case of nonresonant, modified nonresonant, screened nonresonant and resonant cases are given. These are expressed in terms of H-functions, G-functions and in computable series forms. Computational aspects are also discussed.

  8. SYSTEMATIC UNCERTAINTIES IN THE SPECTROSCOPIC MEASUREMENTS OF NEUTRON-STAR MASSES AND RADII FROM THERMONUCLEAR X-RAY BURSTS. II. EDDINGTON LIMIT

    SciTech Connect (OSTI)

    Guever, Tolga; Oezel, Feryal; Psaltis, Dimitrios [Department of Astronomy, University of Arizona, 933 North Cherry Avenue, Tucson, AZ 85721 (United States)

    2012-03-01T23:59:59.000Z

    Time-resolved X-ray spectroscopy of thermonuclear bursts observed from low-mass X-ray binaries offer a unique tool to measure neutron-star masses and radii. In this paper, we continue our systematic analysis of all the X-ray bursts observed with Rossi X-ray Timing Explorer from X-ray binaries. We determine the events that show clear evidence for photospheric radius expansion and measure the Eddington limits for these accreting neutron stars using the bolometric fluxes attained at the touchdown moments of each X-ray burst. We employ a Bayesian technique to investigate the degree to which the Eddington limit for each source remains constant between bursts. We find that for sources with a large number of radius expansion bursts, systematic uncertainties are at a 5%-10% level. Moreover, in six sources with only pairs of Eddington-limited bursts, the distribution of fluxes is consistent with a {approx}10% fractional dispersion. This indicates that the spectroscopic measurements of neutron-star masses and radii using thermonuclear X-ray bursts can reach the level of accuracy required to distinguish between different neutron-star equations of state, provided that uncertainties related to the overall flux calibration of X-ray detectors are of comparable magnitude.

  9. Research project -Master Thesis Investigation of mixed rare earth

    E-Print Network [OSTI]

    's) to fusion devices such as the International Thermonuclear Experimental Reactor (ITER) to superconducting emission-free energy by means of supercon- ducting generators for windmills, fusion reactors etc

  10. Development of an experiment to study the effects of transverse stress on the critical current of a niobium-tin superconducting cable

    E-Print Network [OSTI]

    Chiesa, Luisa

    2006-01-01T23:59:59.000Z

    Superconducting magnets will play a central role for the success of the International Thermonuclear Experimental Reactor (ITER). ITER is a current driven plasma experiment that could set a milestone towards the demonstration ...

  11. On 5 February, President George Bush presented his budget request to Congress

    E-Print Network [OSTI]

    Loss, Daniel

    's Relativistic Heavy Ion Collider was set to abandon running in 2007, and cuts in spending on ITER, the International Thermonuclear Experimental Reactor, threatened a loss of staff, expertise and valuable time

  12. PERFORMANCE BOUNDARIES IN Nb3Sn SUPERCONDUCTORS

    E-Print Network [OSTI]

    of Wisconsin-Madison, USA. This work was supported by the European Union through the European Fusion for the International Thermonuclear Experimental Reactor. Part of the task description was to summarize the results

  13. JOURNAL DE PHYSIQUE IV Colloque C8,supplkmentau Journal de Physique I, Volume 3, d6cembre1993

    E-Print Network [OSTI]

    Boyer, Edmond

    -sur-Yvette,France Abstract. SANS was used to investigate the growth of He-bubbles in a martensitic steel developed for fusion tokamak-based reactors, such as NET/ITER (Next European Torus / International Thermonuclear Experimental

  14. Effects of specimen thickness and impurity on the conductivity of alumina under electron irradiation

    E-Print Network [OSTI]

    Howlader, Matiar R

    windows in the International Thermonuclear Experimental Reactor (ITER), where the electrical conductivity believed to be critical issues for the application of a-Al2O3 to insulators in fusion reac- tors. The RIC

  15. TOP 2014: Experimental Summary

    E-Print Network [OSTI]

    Christian Schwanenberger

    2015-03-05T23:59:59.000Z

    A summary of the experimental results of the TOP2014 International Workshop in Cannes, France, is presented. This inspiring conference clearly showed the richness and diversity of top-quark physics research. Results cover a very broad spectrum of analyses involving studies of the strong and electroweak interactions of the top quark, high-precision measurements of intrinsic top-quark properties, developments of new tools in top-quark analyses, observations of new Standard Model processes, the interaction between the top quark and the Higgs boson and sensitive searches for new physics beyond the Standard Model.

  16. Amnesty International

    ScienceCinema (OSTI)

    None

    2011-04-25T23:59:59.000Z

    Martin Ennals est secrétaire général d'Amnesty International et fait un discours sur les droits de l'homme

  17. ENGINEERING INTERNATIONAL

    E-Print Network [OSTI]

    University of Technology, Sydney

    COURSE GUIDE 2013 UTS: ENGINEERING INTERNATIONAL UNDERGRADUATE w w w.eng.uts.edu.au #12;2 / ENGINEERING IN AUSTRALIA Internationally, Australian universities have a reputation for high quality research developed close links with many international institutions, particularly in Asia. ENGINEERING IN SYDNEY

  18. Experimental Conclusions

    E-Print Network [OSTI]

    Das, Suman

    Gasification is that any type of biomass (including low cost feedstocks like agricultural residues, forest waste, etc) can be converted to syngas. Pyrolysis and Char gasification proceed sequentially) To obtain experimental data and develop mathematical models on intrinsic char gasification kinetics, free

  19. INTERNAL REPAIR OF PIPELINES

    SciTech Connect (OSTI)

    Robin Gordon; Bill Bruce; Nancy Porter; Mike Sullivan; Chris Neary

    2003-05-01T23:59:59.000Z

    The two broad categories of deposited weld metal repair and fiber-reinforced composite repair technologies were reviewed for potential application for internal repair of gas transmission pipelines. Both are used to some extent for other applications and could be further developed for internal, local, structural repair of gas transmission pipelines. Preliminary test programs were developed for both deposited weld metal repairs and for fiber-reinforced composite repair. To date, all of the experimental work pertaining to the evaluation of potential repair methods has focused on fiber-reinforced composite repairs. Hydrostatic testing was also conducted on four pipeline sections with simulated corrosion damage: two with composite liners and two without.

  20. SYSTEMATIC UNCERTAINTIES IN THE SPECTROSCOPIC MEASUREMENTS OF NEUTRON-STAR MASSES AND RADII FROM THERMONUCLEAR X-RAY BURSTS. I. APPARENT RADII

    SciTech Connect (OSTI)

    Guever, Tolga; Psaltis, Dimitrios; Oezel, Feryal [Department of Astronomy, University of Arizona, 933 N. Cherry Ave., Tucson, AZ 85721 (United States)

    2012-03-01T23:59:59.000Z

    The masses and radii of low-magnetic field neutron stars can be measured by combining different observable quantities obtained from their X-ray spectra during thermonuclear X-ray bursts. One of these quantities is the apparent radius of each neutron star as inferred from the X-ray flux and spectral temperature measured during the cooling tails of bursts, when the thermonuclear flash is believed to have engulfed the entire star. In this paper, we analyze 13,095 X-ray spectra of 446 X-ray bursts observed from 12 sources in order to assess possible systematic effects in the measurements of the apparent radii of neutron stars. We first show that the vast majority of the observed X-ray spectra are consistent with blackbody functions to within a few percent. We find that most X-ray bursts follow a very well determined correlation between X-ray flux and temperature, which is consistent with the whole neutron-star surface emitting uniformly during the cooling tails. We develop a Bayesian Gaussian mixture algorithm to measure the apparent radii of the neutron stars in these sources, while detecting and excluding a small number of X-ray bursts that show irregular cooling behavior. This algorithm also provides us with a quantitative measure of the systematic uncertainties in the measurements. We find that those errors in the spectroscopic determination of neutron-star radii that are introduced by systematic effects in the cooling tails of X-ray bursts are in the range {approx_equal} 3%-8%. Such small errors are adequate to distinguish between different equations of state provided that uncertainties in the distance to each source and the absolute calibration of X-ray detectors do not dominate the error budget.

  1. INTERNATIONAL AGREEMENTS

    Office of Environmental Management (EM)

    generators, reactor pressure vessel and internals, cables, piping, pumps, valves) - optimization of nuclear power plant generation capacity (digital I&C upgrades, advanced...

  2. Lawrence Berkeley Laboratory Institutional Plan FY 1993-98

    E-Print Network [OSTI]

    Chartock, Michael

    2009-01-01T23:59:59.000Z

    experiments. FUSION ENERGY The International ThermonuclearFusion Accelerator Research Health, Safety and Environment Acivisory Committee Induction Linac Systems Experiments International Thermonuclear

  3. The ITER budget is projected to be

    E-Print Network [OSTI]

    's executive arm warned Tuesday that Europe would go ahead and build the International Thermonuclear | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Google It: Foreign Minister Michel Barnier Counterpart Mobutaka Machimura International Thermonuclear

  4. agency international atomic: Topics by E-print Network

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

    501014002 Plasma Physics and Fusion Websites Summary: Harnessing the energy of thermonuclear fusion reactions is one of the greatest challenges of our time. FusionIOP...

  5. astrophysics international workshop: Topics by E-print Network

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

    and cosmological models. Heino Falcke; Peter L. Biermann 1997-11-07 5 Workshop on Thermonuclear Reaction Rates for Astrophysics Applications Computer Technologies and Information...

  6. Determination of astrophysical thermonuclear rates with a bubble chamber: The {sup 12}C(??){sup 16}O reaction case

    SciTech Connect (OSTI)

    DiGiovine, B.; Henderson, D.; Holt, R. J.; Rehm, K. E. [Argonne National Laboratory, Argonne IL 60439 (United States); Grames, J.; Meekins, D.; Poelker, M.; Suleiman, R. [Jefferson Lab, Newport News, VA 23606 (United States); Robinson, A.; Ugalde, C., E-mail: cugalde@uchicago.edu [University of Chicago, Chicago, IL 60637 (United States); Sonnenschein, A. [Fermilab, Batavia, IL 60510 (United States)

    2013-11-07T23:59:59.000Z

    The {sup 12}C(??){sup 16}O reaction rate is considered one of the most important unknown parameters in the physics of structure and evolution of massive stars. While extensive experimental campaigns have been performed trying to improve the quality of the measurements, the rate still holds very large uncertainties. Here we discuss a new experimantal scheme to measure the cross section of this reaction with a bubble chamber and a bremsstrahlung beam. The main advantage of the technique is a gain in the luminosity of several orders of magnitude when compared to other ongoing experiments.

  7. Status of LDRD-DR 20070518 development of a magnetically driven target for thermo-nuclear burn studies (u)

    SciTech Connect (OSTI)

    Watt, Robert G [Los Alamos National Laboratory; Atchison, W L [Los Alamos National Laboratory; Colgate, S A [Los Alamos National Laboratory; Goforth, J [Los Alamos National Laboratory; Griego, J [Los Alamos National Laboratory; Guzik, J [Los Alamos National Laboratory; Holtkamp, D [Los Alamos National Laboratory; Idzorek, G [Los Alamos National Laboratory; Kirkpatrick, R [Los Alamos National Laboratory; Menikoff, R [Los Alamos National Laboratory; Meyer, R [Los Alamos National Laboratory; Oona, H [Los Alamos National Laboratory; Reardon, P [Los Alamos National Laboratory; Rousculp, C L [Los Alamos National Laboratory; Sgro, A G [Los Alamos National Laboratory; Tabaka, L [Los Alamos National Laboratory

    2010-01-20T23:59:59.000Z

    This project is developing a magnetically driven cylindrical confinement system for the creation of a small region of material existing under extreme conditions. Using a Ranchero High Explosive Pulsed Power generator (HEPP) with maximum current ranging from 25- 50 MA depending on the load, a current driven Al cylinder will impact a series of nested, less massive Au shells. Each subsequent shell's inner surface velocity will increase due to it's smaller mass by the ratio 2.01( 1+ m{sub i+ 1}/m i), along with radial convergence. Attaining this ideal result requires highly efficient energy transfer which in turn requires plastic cushions. The final velocity of the last sequential shell will be used to drive a central experimental package in which extreme material conditions will be produced. The inexpensive nature of HEPP and the extreme conditions attainable allow many studies to be conducted in regimes not currently available in the laboratory. One potential central experimental package consists of a cylindrical Inertial Confinement Fusion (ICF) target; a cylindrical Au pusher surrounding frozen DT. This target is used as a design tool. The ICF conditions achieved with such a target would be similar to those created in a double shell ignition capsule at the National Ignition Facility. The system being developed has a range of potential applications.

  8. Two-dimensional simulations of thermonuclear burn in ignition-scale inertial confinement fusion targets under compressed axial magnetic fields

    SciTech Connect (OSTI)

    Perkins, L. J.; Logan, B. G.; Zimmerman, G. B.; Werner, C. J. [Lawrence Livermore National Laboratory, Livermore, California 94550 (United States)] [Lawrence Livermore National Laboratory, Livermore, California 94550 (United States)

    2013-07-15T23:59:59.000Z

    We report for the first time on full 2-D radiation-hydrodynamic implosion simulations that explore the impact of highly compressed imposed magnetic fields on the ignition and burn of perturbed spherical implosions of ignition-scale cryogenic capsules. Using perturbations that highly convolute the cold fuel boundary of the hotspot and prevent ignition without applied fields, we impose initial axial seed fields of 20–100 T (potentially attainable using present experimental methods) that compress to greater than 4 × 10{sup 4} T (400 MG) under implosion, thereby relaxing hotspot areal densities and pressures required for ignition and propagating burn by ?50%. The compressed field is high enough to suppress transverse electron heat conduction, and to allow alphas to couple energy into the hotspot even when highly deformed by large low-mode amplitudes. This might permit the recovery of ignition, or at least significant alpha particle heating, in submarginal capsules that would otherwise fail because of adverse hydrodynamic instabilities.

  9. International Programs and Services International Programs

    E-Print Network [OSTI]

    Stephens, Graeme L.

    International Programs and Services _______________ 1.5 Page 1 International Programs and Services OFFICE OF INTERNATIONAL PROGRAMS Offices in Laurel Hall (970) 491-5917 www.international.colostate.edu James A. Cooney, Vice Provost for International Affairs The Office of International Programs acts

  10. International Programs and Services International Programs

    E-Print Network [OSTI]

    Collett Jr., Jeffrey L.

    International Programs and Services International Programs and Services OFFICE OF INTERNATIONAL PROGRAMS Offices in Laurel Hall (970) 491-5917 international.colostate.edu James A. Cooney, Vice Provost for International Affairs The Office of International Programs acts as a catalyst for ideas that bring about

  11. alkaline tungsten matrix: Topics by E-print Network

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

    Thermonuclear Experimental Reactor Organization, Cadarache, FRANCE 3 Plasma Science and Fusion Thermonuclear Experimental Reactor). Tungsten (W) is the plasma-facing material of...

  12. anthocyanins facilitate tungsten: Topics by E-print Network

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

    Thermonuclear Experimental Reactor Organization, Cadarache, FRANCE 3 Plasma Science and Fusion Thermonuclear Experimental Reactor). Tungsten (W) is the plasma-facing material of...

  13. Internal shim

    DOE Patents [OSTI]

    Barth, Clyde H.; Blizinski, Theodore W.

    2003-05-13T23:59:59.000Z

    An internal shim used to accurately measure spaces in conjunction with a standard small probe has a shim top and a chassis. The internal shim is adjustably fixed within the space to be measured using grippers that emerge from the chassis and which are controlled by an arm pivotably attached to the shim top. A standard small probe passes through the shim along guides on the chassis and measures the distance between the exterior of the chassis and the boundary. By summing the measurements on each side of the chassis and the width of the chassis, the dimension of the space can be determined to within 0.001 inches.

  14. International Educational

    E-Print Network [OSTI]

    Yu, Alex

    International Journal of Educational Technology Opportunities and options for Web-enabled databases.D., Arizona State University The landscape of Web-based instruction is changing due to the convergence of the Web and database servers. Web-based database (WBD) servers enhance Web-based instruction by providing

  15. X-RAY EMISSION AND ABSORPTION FEATURES DURING AN ENERGETIC THERMONUCLEAR X-RAY BURST FROM IGR J17062-6143

    SciTech Connect (OSTI)

    Degenaar, N.; Miller, J. M. [Department of Astronomy, University of Michigan, 500 Church Street, Ann Arbor, MI 48109 (United States); Wijnands, R.; Altamirano, D. [Astronomical Institute ''Anton Pannekoek'', University of Amsterdam, Postbus 94249, 1090 GE Amsterdam (Netherlands); Fabian, A. C., E-mail: degenaar@umich.edu [Institute of Astronomy, University of Cambridge, Madingley Road, Cambridge CB3 OHA (United Kingdom)

    2013-04-20T23:59:59.000Z

    Type-I X-ray bursts are thermonuclear explosions occurring in the surface layers of accreting neutron stars. These events are powerful probes of the physics of neutron stars and their surrounding accretion flow. We analyze a very energetic type-I X-ray burst from the neutron star low-mass X-ray binary IGR J17062-6143 that was detected with Swift on 2012 June 25. The light curve of the {approx_equal}18 minute long X-ray burst tail shows an episode of {approx_equal}10 minutes during which the intensity is strongly fluctuating by a factor of {approx_equal}3 above and below the underlying decay trend on a timescale of seconds. The X-ray spectrum reveals a highly significant emission line around {approx_equal}1 keV, which can be interpreted as an Fe-L shell line caused by the irradiation of cold gas. We also detect significant absorption lines and edges in the Fe-K band, which are strongly suggestive of the presence of hot, highly ionized gas along the line of sight. None of these features are present in the persistent X-ray spectrum of the source. The timescale of the strong intensity variations, the velocity width of the Fe-L emission line (assuming Keplerian motion), and photoionization modeling of the Fe-K absorption features each independently point to gas at a radius of {approx_equal} 10{sup 3} km as the source of these features. The unusual X-ray light curve and spectral properties could have plausibly been caused by a disruption of the accretion disk due to the super-Eddington fluxes reached during the X-ray burst.

  16. Reuters News Article Friday, January 31, 2003 http://www.reuters.com/

    E-Print Network [OSTI]

    FriendlyPopup.jhtml?type=scienceNews& Page: 1 Print This Article Print this article Close This Window U.S. to Join International Fusion an international research project aimed at harnessing the power of fusion and turning it into a clean and safe source for energy, President Bush said on Thursday. ITER, the International Thermonuclear Experimental

  17. Non-diffusive cross field transport in scrape-off-layer in Tokamak

    E-Print Network [OSTI]

    Yu, Guanghui

    2006-01-01T23:59:59.000Z

    tide energy etc. , thermonuclear fusion energy is the mostfusion are still under research, and will surely carry on in the International Thermonuclear

  18. anaerobic hybrid reactor: Topics by E-print Network

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

    required for thermonuclear reactors R@frascati.enea.it Abstract. For the progress of the thermonuclear fusion energy research based on the tokamak concept in ITER (International...

  19. advanced current drive: Topics by E-print Network

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

    required for thermonuclear reactors R@frascati.enea.it Abstract. For the progress of the thermonuclear fusion energy research based on the tokamak concept in ITER (International...

  20. International Feedstock

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels DataDepartment of Energy Your Density Isn't YourTransport(FactDepartment of EnergyIndustry15Among Statesfor a Smart1.2.1.5 International

  1. International Conference

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOEThe Bonneville PowerCherries 82981-1cnHigh SchoolIn Other NewsSpinInteragency1Princeton PlasmaInternationalA

  2. International H

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOEThe Bonneville PowerCherries 82981-1cnHigh SchoolIn OtherEnergy International Fuel Services and Commercial2

  3. International Sunport

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOEThe Bonneville PowerCherries 82981-1cnHigh SchoolIn OtherEnergy International Fuel Services»Challenges

  4. Condensed hydrogen for thermonuclear fusion

    SciTech Connect (OSTI)

    Kucheyev, S. O.; Hamza, A. V. [Nanoscale Synthesis and Characterization Laboratory, Lawrence Livermore National Laboratory, Livermore, California 94551 (United States)

    2010-11-15T23:59:59.000Z

    Inertial confinement fusion (ICF) power, in either pure fusion or fission-fusion hybrid reactors, is a possible solution for future world's energy demands. Formation of uniform layers of a condensed hydrogen fuel in ICF targets has been a long standing materials physics challenge. Here, we review the progress in this field. After a brief discussion of the major ICF target designs and the basic properties of condensed hydrogens, we review both liquid and solid layering methods, physical mechanisms causing layer nonuniformity, growth of hydrogen single crystals, attempts to prepare amorphous and nanostructured hydrogens, and mechanical deformation behavior. Emphasis is given to current challenges defining future research areas in the field of condensed hydrogens for fusion energy applications.

  5. anaerobic reactor systems: Topics by E-print Network

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

    Thermonuclear Experimental Reactor and the Nuclear Weapons Proliferation Implications of Thermonuclear-Fusion Energy Systems CiteSeer Summary: This paper contains two parts: (I) A...

  6. army weapon systems: Topics by E-print Network

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

    Thermonuclear Experimental Reactor and the Nuclear Weapons Proliferation Implications of Thermonuclear-Fusion Energy Systems CiteSeer Summary: This paper contains two parts: (I) A...

  7. annular reactor system: Topics by E-print Network

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

    Thermonuclear Experimental Reactor and the Nuclear Weapons Proliferation Implications of Thermonuclear-Fusion Energy Systems CiteSeer Summary: This paper contains two parts: (I) A...

  8. Ris-R-1007(EN) Influence of Composition, Heat

    E-Print Network [OSTI]

    Thermonuclear Experimental Reactor). The alloys have undergone different pre-irradiation heat treatments which- eration for their applications in the structural components of ITER (Inter- national Thermonuclear

  9. Magnetic Braids Anthony Yeates

    E-Print Network [OSTI]

    Dundee, University of

    flux function Main result Conclusion 2. Thermonuclear confinement devices. ITER (Internat'l Thermonuclear Experimental Reactor). Inside the KSTAR tokamak. Correspond to periodic magnetic braids. 4 / 22

  10. Control of tearing modes in toroidal fusion experiments using ``designer'' error fields

    E-Print Network [OSTI]

    Rossi, Enrico

    experimental results strongly suggest that further progress in obtaining thermonuclear reactor grade plasmas, placing feedback coils this close to a thermonuclear plasma is essentially impossible in a reactor

  11. INERTIAL FUSION DRIVEN BY INTENSE HEAVY-ION BEAMS

    E-Print Network [OSTI]

    Sharp, W. M.

    2011-01-01T23:59:59.000Z

    Thermonuclear Experimental Reactor), now being constructed in Caderache, France [5]. In contrast, inertial fusion

  12. 70 IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY, VOL. 18, NO. 2, JUNE 2008 High Field Superconducting Solenoids Via High

    E-Print Network [OSTI]

    an essential role in fusion devices, including the Interna- tional Thermonuclear Experimental Reactor [6], [7

  13. Ris-R-1276(EN) Final Report

    E-Print Network [OSTI]

    Thermonuclear Experimental Reactor) [1,2]. Since very little was known about the effect of irradiation

  14. International Student Services Office International Student Mentor

    E-Print Network [OSTI]

    Dawson, Jeff W.

    International Student Services Office International Student Mentor Undergraduate and Graduate stages of their transition to academic life at Carleton University. Mentors play a central role in ensuring student success by providing guidance and academic coaching. All ISSO mentors report

  15. 21 11 13 INTERNATIONAL

    E-Print Network [OSTI]

    Yamamoto, Hirosuke

    31 E 32 F 32 #12; iv INTERNATIONAL ERGONOMICS ASSOCIATION #12; 3 INTERNATIONAL ERGONOMICS ASSOCIATION CODE OF CONDUCT ERGONOMICS ASSOCIATION (2006) http://www.iea.cc/browse.php?contID=international_ergonomics_association A6

  16. Numerical and Experimental Investigation of Internal Short Circuit...

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

    Merit Review and Peer Evaluation es109kim2011p.pdf More Documents & Publications Battery Thermal Modeling and Testing Implantation, Activation, Characterization and...

  17. Physica Scripta An International Journal for Experimental and Theoretical Physics

    E-Print Network [OSTI]

    Nordlund, Kai

    Telephone Telefax Electronic Mail Home Page Physica Scripta +46-(0)8-673 95 00 +46-(0)8-673 95 90 physica frequency !o and the migration energy Em of interstitial graphite which are inputs to the KMC. A consistent parameterization of MD within KMC is presented. The diffusion shows a non-Arrhenius behavior which can be explained

  18. First international conference in numerical and experimental aerodynamics of

    E-Print Network [OSTI]

    separation location. Jet to crossflow velocity ratios (B) of 1.5 and 3 are explored. As the jets inject into the crossflow, counter-rotating vortex pairs (CVPs) are formed enhancing the mixing of high momentum outer fluid

  19. Numerical and Experimental Investigation of Internal Short Circuit in a

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels DataDepartment of Energy Your Density Isn'tOrigin of Contamination in ManyDepartment of Energy NorthBDepartmentEnergyPCCI

  20. International Topical Meeting on Nuclear Reactor Thermal-Hydraulics (NURETH-11) Popes' Palace Conference Center, Avignon, France, October 2-6, 2005.

    E-Print Network [OSTI]

    Lahey, Richard T.

    evidence supporting the observed production of neutrons and tritium due to thermonuclear fusion within of cavitation bubbles which are suitable for thermonuclear fusion (i.e., ultra-high temperatures, pressures of Sonofusion is that of thermonuclear fusion, and thus is quite different from any "new" physics which may

  1. Student Trainee (Engineering)- Intern

    Broader source: Energy.gov [DOE]

    The purpose of the Pathways Intern Employment Program is to provide the intern with exposure to public service, enhance educational experience, and support educational goals. The program is...

  2. International Commitments Management

    Broader source: Directives, Delegations, and Requirements [Office of Management (MA)]

    2008-11-18T23:59:59.000Z

    This Order establishes a process to manage the Department's International Commitments under the administrative direction of the Office of Policy and International Affairs. No cancellation.

  3. Internal Controls Evaluations

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

    iPortal Space. III. GAO Standards for Internal Control in the Federal Government In 1999, GAO issued revised Standards for Internal Control in the Federal Government. This...

  4. International Subcommittee Report

    Energy Savers [EERE]

    and overall U.S. international nuclear commercial leadership as part of the "Team USA" approach NEAC Meeting December 10, 2014 4 Recommendations by the NEAC International...

  5. Monday, February 23, 2004 Decision on site for fusion project is put off again

    E-Print Network [OSTI]

    Monday, February 23, 2004 Decision on site for fusion project is put off again VIENNA (Kyodo) The six parties involved in an international nuclear fusion project have again failed to decide on either in March. Senior officials of the parties to the International Thermonuclear Experimental Reactor project

  6. White Paper on Magnetic Fusion Program Strategies

    E-Print Network [OSTI]

    of the international fusion program, the International Thermonuclear Experimental Reactor (ITER), is now halfwayWhite Paper on Magnetic Fusion Program Strategies Prepared for The President's Committee of Advisors on Science and Technology Prepared by David E. Baldwin Senior Vice President for Fusion General

  7. TechnologyReview.com |Print Forums

    E-Print Network [OSTI]

    TechnologyReview.com |Print Forums International Fusion Research By Ian H. Hutchinson July 8, 2005 The announcement in the last week that the site for the International Thermonuclear Experimental Reactor (ITER) is finally resolved is a source of relief and anticipation to nuclear fusion researchers worldwide. It opens

  8. Board on Physics and Astronomy 500 Fifth Street, NW, Washington, D.C. 20001

    E-Print Network [OSTI]

    on the International Thermonuclear Experimental Reactor (ITER), an international burning plasma experiment.1 of a burning plasma experiment for fusion energy and the scientific and technical readiness to undertake plasma issue and their relation to the fusion energy science program. In particular, considerations

  9. Assessor Training International

    E-Print Network [OSTI]

    NVLAP Assessor Training International Arrangements #12;Assessor Training 2009: International;Assessor Training 2009: International Arrangements 3 2009 is the 10th anniversary of the signing granted by a signatory to the ILAC Arrangement #12;Assessor Training 2009: International Arrangements 4

  10. STEP Intern Job Description

    Broader source: Energy.gov [DOE]

    STEP Intern Job Description, from the Tool Kit Framework: Small Town University Energy Program (STEP).

  11. 3. EXPERIMENTAL METHODS ACKNOWLEDGMENTS

    E-Print Network [OSTI]

    and experimental analysis for water in soil. J. Non-Equil. Thermodyn. 34(2):133-153. Bixler, N.E. 1985. NORIA

  12. Experimental quantum field theory

    E-Print Network [OSTI]

    Bell, J S

    1977-01-01T23:59:59.000Z

    Presented here, is, in the opinion of the author, the essential minimum of quantum field theory that should be known to cultivated experimental particle physicists. The word experimental describes not only the audience aimed at but also the level of mathematical rigour aspired to. (0 refs).

  13. 11/21/2006 07:40 AMITAR-TASS Page 1 of 2http://www.itar-tass.com/eng/prnt.html?NewsID=11003725

    E-Print Network [OSTI]

    by means of thermonuclear fusion at new power plants. The total cost of the project, in which approximately thermonuclear experimental reactor (ITER) was signed at the Elysee Palace here on Tuesday. Representatives the thermonuclear synthesis and had carried out a broad range of experimental works on "Tokamak" thermonuclear

  14. Internal Wave Interferometry

    E-Print Network [OSTI]

    Mathur, Manikandan S.

    Internal waves are a ubiquitous and significant means of momentum and energy transport in the oceans, atmosphere, and astrophysical bodies. Here, we show that internal wave propagation in nonuniform density stratifications, ...

  15. Essays in international trade

    E-Print Network [OSTI]

    Romalis, John

    2001-01-01T23:59:59.000Z

    This thesis is a collection of essays on the effect of trade costs on international trade. Chapter 1 derives and empirically examines how factor proportions determine the structure of commodity trade when international ...

  16. International aeronautical user charges

    E-Print Network [OSTI]

    Odoni, Amedeo R.

    1985-01-01T23:59:59.000Z

    Introduction: 1.1 BACKGROUND AND MOTIVATION Very few issues relating to the international air transportation industry are today as divisive as those pertaining to user charges imposed at international airports and enroute ...

  17. Nuclear test experimental science

    SciTech Connect (OSTI)

    Struble, G.L.; Middleton, C.; Bucciarelli, G.; Carter, J.; Cherniak, J.; Donohue, M.L.; Kirvel, R.D.; MacGregor, P.; Reid, S. (eds.)

    1989-01-01T23:59:59.000Z

    This report discusses research being conducted at Lawrence Livermore Laboratory under the following topics: prompt diagnostics; experimental modeling, design, and analysis; detector development; streak-camera data systems; weapons supporting research.

  18. International Exeter annual report

    E-Print Network [OSTI]

    -chancellor's international engagement 68 China and Hong Kong 74 India 78 United States of America 82 United Arab Emirates 88

  19. International Exeter annual report

    E-Print Network [OSTI]

    -Chancellor's international engagement 66 China and Hong Kong 72 India 76 United States of America 80 United Arab Emirates 86

  20. International and Finance

    E-Print Network [OSTI]

    Little, Tony

    MSc International Accounting and Finance #12;What is International Accounting and Finance and why involved. Why study International Accounting and Finance at Stirling? One In the most recent Research Assessment Exercise, the University of Stirling's division of Accounting and Finance was rated first equal

  1. INTERNATIONAL STUDENT ADMISSIONS

    E-Print Network [OSTI]

    Fernandez, Eduardo

    Marine Renewable Energy Center, one of only three in the country. u Benefit from FAU's collaborativeADMISSIONS INTERNATIONAL STUDENT ADMISSIONS INTERNATIONAL STUDENT ADMISSIONS A cutting-edge research university that offers a high-quality education WWW.FAU.EDU/INTERNATIONAL[FAU] #12;WORLD

  2. From Domestic vs. International to Domestic and International

    E-Print Network [OSTI]

    Amin, S. Massoud

    % 20% 30% 40% 50% 60% 70% 80% 90% 100% Domestic International International Domestic 100% 67% 86% 29

  3. Experimental Scattershot Boson Sampling

    E-Print Network [OSTI]

    Marco Bentivegna; Nicolò Spagnolo; Chiara Vitelli; Fulvio Flamini; Niko Viggianiello; Ludovico Latmiral; Paolo Mataloni; Daniel J. Brod; Ernesto F. Galvão; Andrea Crespi; Roberta Ramponi; Roberto Osellame; Fabio Sciarrino

    2015-05-14T23:59:59.000Z

    Boson Sampling is a computational task strongly believed to be hard for classical computers, but efficiently solvable by orchestrated bosonic interference in a specialised quantum computer. Current experimental schemes, however, are still insufficient for a convincing demonstration of the advantage of quantum over classical computation. A new variation of this task, Scattershot Boson Sampling, leads to an exponential increase in speed of the quantum device, using a larger number of photon sources based on parametric downconversion. This is achieved by having multiple heralded single photons being sent, shot by shot, into different random input ports of the interferometer. Here we report the first Scattershot Boson Sampling experiments, where six different photon-pair sources are coupled to integrated photonic circuits. We employ recently proposed statistical tools to analyse our experimental data, providing strong evidence that our photonic quantum simulator works as expected. This approach represents an important leap toward a convincing experimental demonstration of the quantum computational supremacy.

  4. Experimental probes of axions

    SciTech Connect (OSTI)

    Chou, Aaron S.; /Fermilab

    2009-10-01T23:59:59.000Z

    Experimental searches for axions or axion-like particles rely on semiclassical phenomena resulting from the postulated coupling of the axion to two photons. Sensitive probes of the extremely small coupling constant can be made by exploiting familiar, coherent electromagnetic laboratory techniques, including resonant enhancement of transitions using microwave and optical cavities, Bragg scattering, and coherent photon-axion oscillations. The axion beam may either be astrophysical in origin as in the case of dark matter axion searches and solar axion searches, or created in the laboratory from laser interactions with magnetic fields. This note is meant to be a sampling of recent experimental results.

  5. Comparison of the recently proposed super-Marx generator approach to thermonuclear ignition with the deuterium-tritium laser fusion-fission hybrid concept by the Lawrence Livermore National Laboratory

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

    Winterberg, F.

    2009-10-29T23:59:59.000Z

    The recently proposed super-Marx generator pure deuterium microdetonation ignition concept is compared to the Lawrence Livermore National Ignition Facility (NIF) Laser deuterium-tritium fusion-fission hybrid concept (LIFE). In a super-Marx generator, a large number of ordinary Marx generators charge up a much larger second stage ultrahigh voltage Marx generator from which for the ignition of a pure deuterium microexplosion an intense GeV ion beam can be extracted. Typical examples of the LIFE concept are a fusion gain of 30 and a fission gain of 10, making up a total gain of 300, with about ten times more energy released into fission as compared to fusion. This means the substantial release of fission products, as in fissionless pure fission reactors. In the super-Marx approach for the ignition of pure deuterium microdetonation, a gain of the same magnitude can, in theory, be reached. If feasible, the super-Marx generator deuterium ignition approach would make lasers obsolete as a means for the ignition of thermonuclear microexplosions.

  6. Comparison of the recently proposed super-Marx generator approach to thermonuclear ignition with the deuterium-tritium laser fusion-fission hybrid concept by the Lawrence Livermore National Laboratory

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

    Winterberg, F.

    2009-01-01T23:59:59.000Z

    The recently proposed super-Marx generator pure deuterium microdetonation ignition concept is compared to the Lawrence Livermore National Ignition Facility (NIF) Laser deuterium-tritium fusion-fission hybrid concept (LIFE). In a super-Marx generator, a large number of ordinary Marx generators charge up a much larger second stage ultrahigh voltage Marx generator from which for the ignition of a pure deuterium microexplosion an intense GeV ion beam can be extracted. Typical examples of the LIFE concept are a fusion gain of 30 and a fission gain of 10, making up a total gain of 300, with about ten times more energy released into fissionmore »as compared to fusion. This means the substantial release of fission products, as in fissionless pure fission reactors. In the super-Marx approach for the ignition of pure deuterium microdetonation, a gain of the same magnitude can, in theory, be reached. If feasible, the super-Marx generator deuterium ignition approach would make lasers obsolete as a means for the ignition of thermonuclear microexplosions.« less

  7. Experimental Neutrino Physics

    ScienceCinema (OSTI)

    Chris Walter

    2010-01-08T23:59:59.000Z

    In this talk, I will review how a set of experiments in the last decade has given us our current understanding of neutrino properties.  I will show how experiments in the last year or two have clarified this picture, and will discuss how new experiments about to start will address remaining questions.  I will particularly emphasize the relationship between various experimental techniques.

  8. Experimental Capabilities & Apparatus

    E-Print Network [OSTI]

    Oak Ridge National Laboratory

    top-10 green building product" by BuildingGreen, Inc. at the US Green Building Council's annual GreenBuildExperimental Capabilities & Apparatus Directory Building Technologies Research and Integration Center #12;Building Technologies Research Oak Ridge National Laboratory's (ORNL) Building Technologies

  9. Internal dosimetry software comparison

    E-Print Network [OSTI]

    Fulmer, Judith Renee

    1992-01-01T23:59:59.000Z

    (ICRP) published in 1979 provided an improved approach for the assessment of internal dose. The ICRP recommendations were implemented in federal regulations promulgated by the Nuclear Regulatory Commission (NRC) in the Code of Federal Regulations (10... in the assessment of internal dose has led to the development of various computer software. In this study, several internal dosimetry codes were examined using a standard set of benchmark problems incorporating authentic exposure data. Personal computer...

  10. EM International. Volume 1

    SciTech Connect (OSTI)

    Not Available

    1993-07-01T23:59:59.000Z

    It is the intent of EM International to describe the Office of Environmental Restoration and Waste Management`s (EM`s) various roles and responsibilities within the international community. Cooperative agreements and programs, descriptions of projects and technologies, and synopses of visits to international sites are all highlighted in this semiannual journal. Focus on EM programs in this issue is on international collaboration in vitrification projects. Technology highlights covers: in situ sealing for contaminated sites; and remote sensors for toxic pollutants. Section on profiles of countries includes: Arctic contamination by the former Soviet Union, and EM activities with Germany--cooperative arrangements.

  11. High efficiency cavity design of a 170 GHz gyrotron for fusion applications R. A. Correa,a)

    E-Print Network [OSTI]

    Hassam, Adil

    power and cooling systems of gyro- tron and the numbers of gyrotrons in the ECRH system. In this paper,2 For in- stance, the gyrotron system for ECRH on the International Thermonuclear Experimental Reactor ITER around the world and great progress has been achieved.1,2,4­7 In recent experiments and designs

  12. Signicance of sample thickness and surface segregation on the electrical conductivity of Wesgo AL995 alumina under ITER

    E-Print Network [OSTI]

    Howlader, Matiar R

    are expected to be used in fusion reactors like international thermonuclear experimental reactor (ITER insulating material in fusion reactors [1] because of its high thermal conductivity [2], high resistance of alumina are to be used in fusion reactors, no studies have ever been done on the thickness dependence

  13. US House of Representatives Appropriation Committee Report May 18, 2005

    E-Print Network [OSTI]

    US House of Representatives Appropriation Committee Report May 18, 2005 Fusion Energy Sciences The Committee recommendation for fusion energy sciences is $295,155,000, an increase of $5,605,000 over that two-thirds of the proposed increase for the International Thermonuclear Experimental Reactor (ITER

  14. ---Home Yahoo! Help My Yahoo! http://asia.news.yahoo.com/041102/kyodo/d863kr500.html

    E-Print Network [OSTI]

    November 2, 17:04 PM Japan, EU, others to discuss nuclear fusion reactor next week Japan, the European where they will build the world's first prototype nuclear fusion reactor, Japan's science ministry said are together working on the International Thermonuclear Experimental Reactor project will meet next Tuesday

  15. Wednesday, February 4, 2004 Search Archives

    E-Print Network [OSTI]

    , repeated Japan's desire to host the world's first prototype nuclear fusion reactor in Rokkasho, Aomori to Japan Book club InterFM radio Japan Times Jobs E L E C Study abroad Business jet charter Hotel bargains to iron out their differences over the site of the International Thermonuclear Experimental Reactor

  16. Fusion Energy Program Presentation to

    E-Print Network [OSTI]

    International Thermonuclear Experimental Reactor Plasma Technologies Fusion Technologies Advanced MaterialsFusion Energy Program Presentation to Field Work Proposals Washington, D.C. N. Anne Davies Associate Director for Fusion energy Office of Energy Research March23, 1994 #12;FUSION ENERGY PROGRAM FYI

  17. House Appropriations Committee'Report FY04 Energy and Water Development Act

    E-Print Network [OSTI]

    House Appropriations Committee'Report FY04 Energy and Water Development Act Fusion-relevant Sections "FUSION ENERGY SCIENCES "The Committee recommendation for fusion energy sciences is $268 of the Administration's proposal to re-engage in the International Thermonuclear Experimental Reactor (ITER) project

  18. France, Japan vie for fusion site From AFP 21feb04

    E-Print Network [OSTI]

    France, Japan vie for fusion site From AFP 21feb04 THE European Union, Russia, China, the United-billion dollar nuclear fusion reactor, officials said. But no final decision was expected on breaking the deadlock over where to base the International Thermonuclear Experimental Reactor (ITER), the officials

  19. DOE/El+0664 Strategic Plan

    E-Print Network [OSTI]

    activities of the International Thermonuclear Experimental Reactor program, ITER. This restructured fusionDOE/El+0664 Strategic Plan for the Restructured U.S. Fusion Energy Sciences Program August 1996 U. S. Department of Energy Office of Energy Research Office of Fusion Energy Sciences Germantown, MD

  20. Turbulence in Wendelstein 7-AS plasmas measured by collective light

    E-Print Network [OSTI]

    Basse, Nils Plesner

    of controlled fusion on Earth is called the International Thermonuclear Experimental Reactor (ITER does embody what fusion research is all about. The uncontrolled use of nuclear fusion - the Hydrogen of nuclear fusion energy seems finally to be within our reach. The design to demonstrate the use

  1. France to win huge nuclear fusion project 10:42 24 June 2005

    E-Print Network [OSTI]

    ://www.newscientist.com/article.ns?id=mg18524831.100 22 January 2005 Weblinks International Thermonuclear Experimental Reactor http://www.ofes.fusionFrance to win huge nuclear fusion project 10:42 24 June 2005 NewScientist.com news service Rob Edwards A long and bitter dispute about where to site the world's largest nuclear fusion reactor looks all

  2. Presented to National Research Council

    E-Print Network [OSTI]

    International Thermonuclear Experimental Reactor Design Deuterium- Tritium 1990 2000 2010 2020 Tokamak Fusion By Associate Director for Fusion Energy Sciences Office of Science Department of Energy November 18, 2002 www.ofes.fusion.doe.gov U.S. Fusion Energy Sciences ProgramU.S. Fusion Energy Sciences Program Excellent Science in Support

  3. ITER & Fusion Research Reference: MEMO/10/165 Date: 05/05/2010

    E-Print Network [OSTI]

    ITER & Fusion Research Reference: MEMO/10/165 Date: 05/05/2010 HTML: EN PDF: EN DOC: EN MEMO/10/165 Brussels, 5th May 2010 ITER & Fusion Research The Commission has adopted a Communication to the European for International Thermonuclear Experimental Reactor (ITER), which have more than doubled the costs for Europe (to

  4. Ads by Google Quality Computer

    E-Print Network [OSTI]

    ://www.newscientist.com/article.ns?id=dn7361 10 May 2005 Weblinks International Thermonuclear Experimental Reactor http://www.ofes.fusion | E PLORE BY SUBJECTX | AST WORDL | UBSCRIBES | SEAR HC | RCHIVEA | SSR | OBSJ Biggest nuclear fusion's biggest nuclear fusion reactor, a $12 billion project designed to harness the power of the Sun

  5. U.S. to Participate in Fusion Project Thursday, January 30, 2003 http://www.nytimes.com/aponline/national/AP-Fusion-Energy-Plan.html?pagewanted=

    E-Print Network [OSTI]

    States plan to build a $5 billion fusion reactor, called the International Thermonuclear ExperimentalU.S. to Participate in Fusion Project Thursday, January 30, 2003 http://www.nytimes.com/aponline/national/AP-Fusion-Energy-Plan.html?pagewanted= print&position=top Page: 1 January 30, 2003 U.S. to Participate in Fusion Project By THE ASSOCIATED

  6. June 28, 2005 France to Be Site of World's First Nuclear Fusion Reactor

    E-Print Network [OSTI]

    June 28, 2005 France to Be Site of World's First Nuclear Fusion Reactor By CRAIG S. SMITH PARIS fusion reactor, an estimated $12 billion project that many scientists see as essential to solving chose the country as the site for the International Thermonuclear Experimental Reactor. Japan, which had

  7. Friday February 20, 2004 Three compromise plans eyed for fusion project site

    E-Print Network [OSTI]

    Friday February 20, 2004 Three compromise plans eyed for fusion project site A team of experts on an international nuclear fusion project has drawn up three compromise proposals in a bid to resolve the row over said. The six parties involved in the Thermonuclear Experimental Reactor (ITER) project have been

  8. Advanced simulation of electron heat transport in fusion plasmas , S Klasky2

    E-Print Network [OSTI]

    Lin, Zhihong

    first heat electrons. First-principles simulations of electron turbulence are much more challenging due reactor design relies on the extrapolation of the transport level from present-day fusion experiments to much larger future devices, such as the International Thermonuclear Experimental Reactor (ITER)1

  9. Vessel thermal map real-time system for the JET tokamak R. Felton,2

    E-Print Network [OSTI]

    temperature than the formerly installed carbon fiber composite tiles, imposes strict thermal restrictions of the tritium retention levels when compared with the previous carbon fiber composite (CFC)-based wall [1]. JET of international thermonuclear experimental reactor-relevant materials for the plasma facing components (PFCs

  10. PPPL-3300, Preprint: May 1998, UC-420,423 Tritium Experience in Large Tokamaks: Application to ITER

    E-Print Network [OSTI]

    experience with the use of tritium fuel in the Tokamak Fusion Test Reactor and the Joint European Torus, together with progress in developing the technical design of the International Thermonuclear Experimental Reactor has expanded the technical knowledge base for tritium issues in fusion. This paper reports

  11. PPPL3300, Preprint: May 1998, UC420,423 Tritium Experience in Large Tokamaks: Application to ITER

    E-Print Network [OSTI]

    experience with the use of tritium fuel in the Tokamak Fusion Test Reactor and the Joint European Torus, together with progress in developing the technical design of the International Thermonuclear Experimental Reactor has expanded the technical knowledge base for tritium issues in fusion. This paper reports

  12. House Energy and Water Development FY 2007 Appropriations Passed by House Appropriations Committee May 17, 2006, Status: sent to House

    E-Print Network [OSTI]

    May 17, 2006, Status: sent to House Fusion Energy Sciences ­ Office of Science The Committee recommendation for fusion energy sciences is $318,950,000, the same as the budget request. The Committee in the International Thermonuclear Experimental Reactor (ITER) Project without doing so at the expense of domestic

  13. -News Home Help EU again warns could mount nuclear project without Japan

    E-Print Network [OSTI]

    revealed. news web sites The European Commission ( - ) is set to propose that negotiating strategy next the International Thermonuclear Experimental Reactor (ITER). news web sites Talks in Vienna on Tuesday made some support the Japanese bid -- and Russia and China, which back the EU bid. news web sites Ambassadors from

  14. -News Home Help EU offers 'sweetener' to Japan to let France host nuclear project

    E-Print Network [OSTI]

    to host a revolutionary nuclear fusion project. news web sites "I cannot elaborate on the sweetener, but I Wednesday after talks in Vienna on the International Thermonuclear Experimental Reactor (ITER). news web ( - ) -- which have supported the Japanese bid -- plus Russia and China, which back the EU bid.news web sites

  15. Japan Denies Report It Dropped Proposal to Host Fusion Reactor

    E-Print Network [OSTI]

    Print Japan Denies Report It Dropped Proposal to Host Fusion Reactor June 22 (Bloomberg) -- Japan fusion reactor, a decision that would end a standoff with France to site the 4.6 billion-euro ($5 the International Thermonuclear Experimental Reactor in return for assurances it will manage the project in France

  16. | |SAVE THIS EMAIL THIS Close Japan ups bid for fusion reactor site

    E-Print Network [OSTI]

    Powered by | |SAVE THIS EMAIL THIS Close Japan ups bid for fusion reactor site TOKYO, Japan (AP billion if the project's sponsors build the reactor in Japan, a newspaper reported Wednesday. Construction of the U.S. $12 billion International Thermonuclear Experimental Reactor, or ITER, which would run

  17. Detailed search US supports Japanese bid to host ITER as France urges Europe to go it alone

    E-Print Network [OSTI]

    support of his country for the Japanese bid to host the international thermonuclear site (ITER thermonuclear site if the French candidate is not selected for the international project. However

  18. International decay data evaluation project

    SciTech Connect (OSTI)

    Helmer, R.G.

    1996-10-01T23:59:59.000Z

    Basic concepts of, and information from, radionuclide decay are used in many applications. The author limits this discussion to the data needed for applied {gamma}-ray spectrometry; this includes applications such as nuclide identification and quantitative assay. Many of these applications require a knowledge of half-lives and radiation energies and emission probabilities. For over 50 years, people have compiled and evaluated measured data with the goal of obtaining the best values of these quantities. This has resulted in numerous sets of recommended values, many of which still have scientific, historical, or national reasons for existing. These sets show varying degrees of agreement and disagreement in the quoted values and varying time lags in incorporating new and improved experimental results. A new informational international group has been formed to carry out evaluations for radionuclides of importance in applications; it is expected that the results will become an authoritative and widely accepted set of decay data.

  19. International Programs in Agriculture

    E-Print Network [OSTI]

    International Programs in Agriculture MessagefromtheDirector­ Staying Ahead of Globalization and more prosperous place for all. Fortunately, Purdue International Programs in Agriculture (IPIA) has natural disasters caution us to remember the power of nature. The United Nations Food and Agriculture

  20. Internal Turing Machines

    E-Print Network [OSTI]

    Ken Loo

    2004-07-28T23:59:59.000Z

    Using nonstandard analysis, we will extend the classical Turing machines into the internal Turing machines. The internal Turing machines have the capability to work with infinite ($*$-finite) number of bits while keeping the finite combinatoric structures of the classical Turing machines. We will show the following. The internal deterministic Turing machines can do in $*$-polynomial time what a classical deterministic Turing machine can do in an arbitrary finite amount of time. Given an element of $\\in HALT$ (more precisely, the $*$-embedding of $HALT$), there is an internal deterministic Turing machine which will take $$ as input and halt in the $"yes"$ state. The language ${}^*Halt$ can not be decided by the internal deterministic Turing machines. The internal deterministic Turing machines can be viewed as the asymptotic behavior of finite precision approximation to real number computations. It is possible to use the internal probabilistic Turing machines to simulate finite state quantum mechanics with infinite precision. This simulation suggests that no information can be transmitted instantaneously and at the same time, the Turing machine model can simulate instantaneous collapse of the wave function. The internal deterministic Turing machines are powerful, but if $P \

  1. Conference Proceedings International Conference

    E-Print Network [OSTI]

    Hemmers, Oliver

    Conference Proceedings 10th International Conference on Hand-Arm Vibration 7-11 June 2004 Flamingo related to HAVS. The published proceedings from these conferences have become blueprints for assessing, the entertainment capital of the world: The 10th International Hand-Arm Vibration Conference will be the second time

  2. Blue Award 2012 International

    E-Print Network [OSTI]

    Blue Award 2012 · International Student Competition for Sustainable Architecture Sign in: www.blueaward.at Blue Award 2012 · International Student Competition for Sustainable Architecture Organizers Vienna blueaward.at Organizers Vienna University of Technology Department for Spatial and Sustainable Design

  3. International Conference on

    E-Print Network [OSTI]

    Zevenhoven, Ron

    of energy systems; 5.Refrigeration & air conditioning; Heat pumps; 6.Fuel cells; 7.Biomass / biofuels; bio E C o S 2 0 JuNE 15-19 27th International Conference on Efficiency, Cost, 1 4 Optimization International Conference on Efficiency, Cost, Optimization, Simulation and Environmental Impact of Energy

  4. Students' Perceptions of International Agriculture After an International Agricultural Experience 

    E-Print Network [OSTI]

    Miller, Kasey Lynn

    2012-02-14T23:59:59.000Z

    /schedule, language, safety and health, and time away from home; finally, benefits included experience in international agriculture and natural resources, culture, international travel, global perspective, and education. This study found that international agriculture...

  5. Sustainable Development Summer Intern Report 2013 Sustainable Development Summer Intern

    E-Print Network [OSTI]

    Sustainable Development Summer Intern Report 2013 Sustainable Development Summer Intern Final amongst university's invested in sustainable development. Our small but mighty size allows us to build through positive sustainable practices. As the Sustainable Development Summer Intern I am fortunate enough

  6. Sustainable Development Summer Intern Report 2010 Sustainable Development Summer Intern

    E-Print Network [OSTI]

    Sustainable Development Summer Intern Report 2010 1 Sustainable Development Summer Intern Final of Bishop's University. The role of the Sustainable Development Summer Intern (SDSI) is to coordinate and organize sustainable development information and activities during the summer months. Ensuring

  7. Electrodeless Experimental Thruster

    SciTech Connect (OSTI)

    Brainerd, Jerome J.; Reisz, Al [Reisz Engineers 2909 Johnson Rd. Huntsville, AL 35805 256-883-2531 (United States)

    2009-03-16T23:59:59.000Z

    An electrodeless experimental electric thruster has been built and tested at the NASA Marshall Space Flight Center (MSFC). The plasma is formed by Electron-Cyclotron Resonance (ECR) absorption of RF waves (microwaves). The RF source operates in the 1 to 2 kW range. The plasma is overdense and is confined radially by an applied axial dc magnetic field. The field is shaped by a strong magnetic mirror on the upstream end and a magnetic nozzle on the downstream end. Argon is used as the propellant. The velocity profile in the exhaust plume has been measured with Laser Induced Fluorescence (LIF). An unusual bimodal velocity profile has been measured.

  8. Experimental Highlights - 2014

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOEThe Bonneville Power AdministrationField8,Dist. Category UC-l 1,Energy Consumers |experimental highlights

  9. Experimental Opportunities with LCLS

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOEThe Bonneville Power AdministrationField8,Dist. Category UC-l 1,Energy Consumers |experimental

  10. Quasi-experimental and experimental approaches to environmental economics

    E-Print Network [OSTI]

    Greenstone, Michael

    2007-01-01T23:59:59.000Z

    This paper argues that an increased application of quasi-experimental and experimental techniques will improve understanding about core environmental economics questions. This argument is supported by a review of the ...

  11. Quasi-experimental and experimental approaches to environmental economics

    E-Print Network [OSTI]

    Greenstone, Michael

    This paper argues that an increased application of quasi-experimental and experimental techniques will improve understanding about core environmental economics questions. This argument is supported by a review of the ...

  12. INTERNATIONAL SPACE EXPLORATION COORDINATION GROUP

    E-Print Network [OSTI]

    space exploration infrastructure standards facilitating interoperability through an international with relevant existing international working groups/ organisations. · Preparation and Organization of a WS1 INTERNATIONAL SPACE EXPLORATION COORDINATION GROUP WORKPLAN Update following 3rd ISECG Meeting

  13. International energy annual 1996

    SciTech Connect (OSTI)

    NONE

    1998-02-01T23:59:59.000Z

    The International Energy Annual presents an overview of key international energy trends for production, consumption, imports, and exports of primary energy commodities in over 220 countries, dependencies, and areas of special sovereignty. Also included are population and gross domestic product data, as well as prices for crude oil and petroleum products in selected countries. Renewable energy reported in the International Energy Annual includes hydroelectric power, geothermal, solar, and wind electric power, biofuels energy for the US, and biofuels electric power for Brazil. New in the 1996 edition are estimates of carbon dioxide emissions from the consumption of petroleum and coal, and the consumption and flaring of natural gas. 72 tabs.

  14. international | netl.doe.gov

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

    International Activity in Gasification and Coal to Liquids Development News Gasifipedia Coal-Biomass Feed Advanced Fuels Synthesis Systems Analyses International Activity Project...

  15. MULTIVESSEL BATCH DISTILLATION EXPERIMENTAL VERIFICATION

    E-Print Network [OSTI]

    Skogestad, Sigurd

    MULTIVESSEL BATCH DISTILLATION ­ EXPERIMENTAL VERIFICATION Bernd Wittgens and Sigurd Skogestad 1 The experimental verification of the operation of a multivessel batch distillation column, operated under total vessels, provides a generalization of previously proposed batch distillation schemes. We propose a simple

  16. Research in: Experimental Photonuclear Physics

    E-Print Network [OSTI]

    Saskatchewan, University of

    & Phenomenology Particle Astrophysics & Cosmology Accelerator Physics Health Physics #12;Experimental Photonuclear cryptography #12;Accelerator Physics Dallin, CLS Staff Particle Accelerator Design · Beam Optics · RF systemsResearch in: Experimental Photonuclear Physics Quantum Entanglement Particle Physics Theory

  17. INTERNATIONAL PACIFIC RESEARCH CENTER

    E-Print Network [OSTI]

    Wang, Yuqing

    INTERNATIONAL PACIFIC RESEARCH CENTER APRIL 2004­MARCH 2005 REPORT SCHOOL OF OCEAN AND EARTH RESEARCH HIGHLIGHTS Indo-Pacific Ocean Climate Pacific Research Center Design by: Susan Yamamoto Printed by: Hagadone Printing Company Photo: Waikiki

  18. CSU Office of International

    E-Print Network [OSTI]

    CSU Office of International Programs - Education Abroad Program Types Currently 750 programs on the OIP Education Abroad website. CSU, through Division of Continuing Education/ Online Education Abroad website. Transfer Semester, year & possibly summer CSU tuition and fees (All other fees

  19. International petroleum statistics report

    SciTech Connect (OSTI)

    NONE

    1996-03-01T23:59:59.000Z

    This report presents data on international oil production, demand, imports, exports, and stocks. World oil production and OECD demand data are for the years 1970 through 1994; OECD stocks from 1973 through 1994; and OECD trade from 1984 through 1994.

  20. Essays on International Economics

    E-Print Network [OSTI]

    Cravino, Javier Pablo

    2013-01-01T23:59:59.000Z

    Journal of International Economics, Vol. 65, 375–99. [33]Journal of Monetary Economics, Vol. 51, No. 1, pp. 1–32. [Trade”, Journal of Monetary Economics, Vol. 54, No. 6, pp.

  1. Formula Hybrid International Competition

    E-Print Network [OSTI]

    Carver, Jeffrey C.

    torque at low speeds than do internal combustion engines, a hybrid could offer competitive advantages with a traditional combustion engine into a hybrid vehicle, overcoming numerous technical challenges along the way

  2. International Studies Degree

    E-Print Network [OSTI]

    Moore, Paul A.

    Attorney Simpson Moncif Law, LLC Customer Service Representative Schindler Elevator Corporation Director Insurance Logistics Account Executive Total Quality Logistics, Inc. Manager of Strategic Planning Eaton Corporation Self-employed/Business Owner Indy Associates, Original Impulse Senior Associate International

  3. International Programs in Agriculture

    E-Print Network [OSTI]

    have any questions or comments. Jess Lowenberg-DeBoer Associate Dean and Director of International husband Luc and son Léonce, moved to Kansas for their new venture in farming; and to Corey Kujawa who left

  4. International Energy Agency

    Broader source: Energy.gov [DOE]

    DOE's market transformation efforts have reached to European and other countries who are part of the international distributed and decentralized energy community. Through its partnership with DOE, the combined heat and power (CHP) program of the International Energy Agency (IEA) conducts research and analysis of CHP markets and deployment efforts around the world and has used lessons learned from U.S. research, development, and deployment efforts to recommend market transformation activities and policies that will lead to new CHP installations worldwide.

  5. SWAT Goes International

    E-Print Network [OSTI]

    Wythe, Kathy

    2007-01-01T23:59:59.000Z

    #1; tx H2O | pg. 18 International researchers and program managers in 90 countries around the world use the Soil and Water Assessment Tool (SWAT) model. Germany, the first country interested in SWAT, uses it to model its large watersheds, said... issues and used SWAT to help assess watersheds and transboundary water issues of the 15-country union, increasing the use of the modeling tool throughout Europe. The U.S. Agency for International Development funded a research project for the Kenyan...

  6. Wood Resources International

    E-Print Network [OSTI]

    .3% Sweden 5.3% Finland 4.1% Russia 13.8% US 37.3% Germany 3.3% France 2.8% Poland 2.1% Other Europe 14 International Wood Fuel Removals in Europe 2002 Turkey 12.2% Poland 3.6% Romania 5.3% Hungary 4.1% Germany 7;Wood Resources International Production of energy from wood fuels in 2000 Source: EUBIONET 0 50 100 150

  7. Weighing international ESCO opportunities

    SciTech Connect (OSTI)

    Smith, D.O.

    1997-06-01T23:59:59.000Z

    The decision to expand into an international market is not an easy one. There are many things to consider. It`s probably an even tougher decision for our type business, energy efficiency Performance Contracting, than most because the ESCO business is so complex and carries a considerable amount of project risks which can be considerably magnified in an international setting. The author presents five areas which need to be addressed in making the decision to pursue the international market. (1) Is the international market worth pursuing? (2) Is your company ready to go international? Can your company handle an international venture in stride without disrupting your domestic business plans? (3) Can you afford it financially? What is the risk? (4) Evaluation of target countries. (5) What about a local partner? What will be the roles of you and your prospective partner, both now and long term? What value will your company continue to bring over the years to assure a successful long term business relationship, not just a short term technology transfer?

  8. Brussels advocates a lone rider for ITER 09/22/2004 Edition

    E-Print Network [OSTI]

    can advance alone to establish the thermonuclear reactor experimental ITER in Cadarache. France in the construction of the future experimental thermonuclear reactor ITER, if Brussels does not manage to convince

  9. Assessor Training Internal Audits and

    E-Print Network [OSTI]

    NVLAP Assessor Training Internal Audits and Management Reviews #12;Assessor Training 2009, quarterly, etc., schedule throughout the year #12;Assessor Training 2009: Internal Audits and Management a copy of the full internal audit schedule. #12;Assessor Training 2009: Internal Audits and Management

  10. STEP Intern Reference Check Sheet

    Broader source: Energy.gov [DOE]

    STEP Intern Reference Check Sheet, from the Tool Kit Framework: Small Town University Energy Program (STEP).

  11. Experimental Particle Physics

    SciTech Connect (OSTI)

    Rosenfeld, Carl [Univ of South Carolina; Mishra, Sanjib R. [Univ of South Carolina; Petti, Roberto [Univ of South Carolina; Purohit, Milind V. [Univ of South Carolina

    2014-08-31T23:59:59.000Z

    The high energy physics group at the University of South Carolina, under the leadership of Profs. S.R. Mishra, R. Petti, M.V. Purohit, J.R. Wilson (co-PI's), and C. Rosenfeld (PI), engaged in studies in "Experimental Particle Physics." The group collaborated with similar groups at other universities and at national laboratories to conduct experimental studies of elementary particle properties. We utilized the particle accelerators at the Fermi National Accelerator Laboratory (Fermilab) in Illinois, the Stanford Linear Accelerator Center (SLAC) in California, and the European Center for Nuclear Research (CERN) in Switzerland. Mishra, Rosenfeld, and Petti worked predominantly on neutrino experiments. Experiments conducted in the last fifteen years that used cosmic rays and the core of the sun as a source of neutrinos showed conclusively that, contrary to the former conventional wisdom, the "flavor" of a neutrino is not immutable. A neutrino of flavor "e," "mu," or "tau," as determined from its provenance, may swap its identity with one of the other flavors -- in our jargon, they "oscillate." The oscillation phenomenon is extraordinarily difficult to study because neutrino interactions with our instruments are exceedingly rare -- they travel through the earth mostly unimpeded -- and because they must travel great distances before a substantial proportion have made the identity swap. Three of the experiments that we worked on, MINOS, NOvA, and LBNE utilize a beam of neutrinos from an accelerator at Fermilab to determine the parameters governing the oscillation. Two other experiments that we worked on, NOMAD and MIPP, provide measurements supportive of the oscillation experiments. Good measurements of the neutrino oscillation parameters may constitute a "low energy window" on related phenomena that are otherwise unobservable because they would occur only at energies way above the reach of conceivable accelerators. Purohit and Wilson participated in the BaBar experiment, which collected data at SLAC until 2008. They continued to analyze the voluminous BaBar data with an emphasis on precision tests of Quantum Chromodynamics and on properties of the "eta_B," a bottom quark paired in a meson with a strange quark. The ATLAS experiment became the principal research focus for Purohit. One of the world's largest pieces of scientific equipment, ATLAS observes particle collisions at the highest-energy particle accelerator ever built, the Large Hadron Collider (LHC) at CERN. Our efforts on ATLAS included participation in the commissioning, calibration, and installation of components called "CSCs". The unprecedented energy of 14 TeV enabled the ATLAS and CMS collaborations to declare discovery of the famous Higgs particle in 2012.

  12. Ideal scaling up of BETHSY experimental results

    SciTech Connect (OSTI)

    Petelin, S.; Mavko, B.; Ravnikar, I. [Univ. of Ljubljana (Slovenia)

    1996-06-01T23:59:59.000Z

    The transient scenario of ISP-27 (International System Problem) was applied in the analysis for real NPP (Nuclear Power Plant). The scenario involves a diameter 5.1 cm (2 inches) cold leg break without available HPSI (High Pressure Safety Injection) and hypothetical operator procedure for secondary system depressurization. The objective was to evaluate the ideal scaling up of BETHSY (Boucle d`Etudes Thermohydraulique Systeme) facility proposed accident management procedure for real NPP and to compare the physical phenomena known from experimental background with the phenomena predicted by RELAP5 simulations of real plant transient. Also, special attention was concentrated on those parts of RELAP5 model where possible multidimensional phenomena may occur.

  13. Dependence of effective internal field of congruent lithium niobate on its domain configuration and stability

    SciTech Connect (OSTI)

    Das, Ranjit, E-mail: ranjitdas.in@gmail.com, E-mail: souvik2cat@gmail.com, E-mail: srirajib@yahoo.com; Ghosh, Souvik, E-mail: ranjitdas.in@gmail.com, E-mail: souvik2cat@gmail.com, E-mail: srirajib@yahoo.com; Chakraborty, Rajib, E-mail: ranjitdas.in@gmail.com, E-mail: souvik2cat@gmail.com, E-mail: srirajib@yahoo.com [Department of Applied Optics and Photonics, University of Calcutta, JD-2, Sector III, Salt Lake, Kolkata 700098 (India)

    2014-06-28T23:59:59.000Z

    Congruent lithium niobate is characterized by its internal field, which arises due to defect clusters within the crystal. Here, it is shown experimentally that this internal field is a function of the molecular configuration in a particular domain and also on the stability of that particular configuration. The measurements of internal field are done using interferometric technique, while the variation of domain configuration is brought about by room temperature high voltage electric field poling.

  14. International energy outlook 1994

    SciTech Connect (OSTI)

    Not Available

    1994-07-01T23:59:59.000Z

    The International Energy Outlook 1994 (IEO94) presents an assessment by the Energy Information Administration (EIA) of the outlook for international energy markets between 1990 and 2010. The report is provided as a statistical service to assist energy managers and analysts, both in government and in the private sector. These forecasts are used by international agencies, Federal and State governments, trade associations, and other planners and decisionmakers. They are published pursuant to the Depart. of Energy Organization Act of 1977 (Public Law 95-91), Section 205(c). The IEO94 projections are based on US and foreign government policies in effect on October 1, 1993-which means that provisions of the Climate Change Action Plan unveiled by the Administration in mid-October are not reflected by the US projections.

  15. International energy strategies

    SciTech Connect (OSTI)

    Dunkerley, J. (ed.)

    1980-01-01T23:59:59.000Z

    The sharp rise in oil prices and the embargo of 1973 to 1974 stimulated a growing interest in international energy questions. One indicator of this interest was the decision in late 1977 to establish an International Association of Energy Economists (IAEE). In 1979 the officers of the IAEE proposed to hold not only an initial annual meeting of the association, but also a two-day Conference on International Energy Issues. Resources for the Future, a Washington-based independent research institute, was asked to cosponsor the two-day conference. These two meetings were held in Washington, DC, on June 4, 5, and 6, 1979. This volume contains the 34 papers of the proceedings, and a separate abstract was prepared for each paper for Energy Abstracts for Policy Analysis (EAPA); 13 papers were selected for Energy Research Abstracts (ERA).

  16. International energy annual 1997

    SciTech Connect (OSTI)

    NONE

    1999-04-01T23:59:59.000Z

    The International Energy Annual presents an overview of key international energy trends for production, consumption, imports, and exports of primary energy commodities in over 220 countries, dependencies, and areas of special sovereignty. Also included are population and gross domestic product data, as well as prices for crude oil and petroleum products in selected countries. Renewable energy reported in the International Energy Annual includes hydroelectric power and geothermal, solar, and wind electric power. Also included are biomass electric power for Brazil and the US, and biomass, geothermal, and solar energy produced in the US and not used for electricity generation. This report is published to keep the public and other interested parties fully informed of primary energy supplies on a global basis. The data presented have been largely derived from published sources. The data have been converted to units of measurement and thermal values (Appendices E and F) familiar to the American public. 93 tabs.

  17. 13th International Conference on Chlamydomonas

    SciTech Connect (OSTI)

    Silflow, Carolyn D. [University of Minnesota

    2014-03-11T23:59:59.000Z

    The 13th International Conference on Chlamydomonas (EMBO Workshop on the Cell and Molecular Biology of Chlamydomonas) was held May 27 to June 1, 2008 in Hyeres, France. The conference was the biennial meeting for all researchers studying the green algal systems Chlamydomonas and Volvox. The conference brought together approximately 200 investigators from around the world (North America, Asia, Europe and Australia) representing different fields and disciplines (cell biology, genetics, biochemistry, biophysics, plant physiology, genomics). It provided an opportunity for investigators from different countries to share methodologies and to discuss recent results with a focus on the Chlamydomonas experimental system.

  18. Experimental constraints on transport

    SciTech Connect (OSTI)

    Luce, T.C.; Petty, K.H.; Burrell, K.H.; Forest, C.B.; Gohil, P.; Groebner, R.J.; De Haas, J.C.M.; James, R.A.; Makowski, M.A.

    1994-12-01T23:59:59.000Z

    Characterization of the cross-field energy transport in magnetic confinement experiments in a manner applicable to the accurate assessment of future machine performance continues to be a challenging goal. Experimental results from the DIII-D tokamak in the areas of dimensionless scaling and non-diffusive transport represent progress toward this goal. Dimensionless scaling shows how beneficial the increase in machine size and magnetic field is for future devices. The experiments on DIII-D are the first to determine separately the electron and ion scaling with normalized gyroradius {rho}{sub *}; the electrons scale as expected from gyro-Bohm class theories, while the ions scale consistent with the Goldston empirical scaling. This result predicts an increase in transport relative to Bohm diffusion as {rho}{sub *} decreases in future devices. The existence of distinct {rho}{sub *} scalings for ions and electrons cautions against a physical interpretation of one-fluid or global analysis. The second class of experiments reported here are the first to demonstrate the existence of non-diffusive energy transport. Electron cyclotron heating was applied at the half radius; the electron temperature profile remains substantially peaked. Power balance analysis indicates that heat must flow in the direction of increasing temperature, which is inconsistent with purely diffusive transport. The dynamics of electron temperature perturbations indicate the presence in the heat flux of a term dependent on temperature rather than its gradient. These two observations strongly constrain the types of models which can be applied to cross-field heat transport.

  19. International petroleum statistics report

    SciTech Connect (OSTI)

    Not Available

    1994-12-01T23:59:59.000Z

    This document is a monthly publication that provides current international oil data. The Report presents data on international oil production, demand, imports, exports, and stocks. Section 1 contains time series data on world oil production, and on oil demand and stocks in the OECD. Section 2 presents an oil supply/demand balance for the world. This balance is presented in quarterly intervals for the most recent two years. Section 3 presents data on oil imports by OECD countries. Section 4 presents annual time series data on world oil production and oil stocks, demand and trade in OECD countries.

  20. Spectropolarimetric diagnostics of thermonuclear supernova explosions

    E-Print Network [OSTI]

    Lifan Wang; Dietrich Baade; Ferdinando Patat

    2006-11-29T23:59:59.000Z

    Even at extragalactic distances, the shape of supernova ejecta can be effectively diagnosed by spectropolarimetry. We present here results for 17 Type Ia supernovae that allow a statistical study of the correlation among the geometric structures and other observable parameters of Type Ia supernovae. These observations suggest that their ejecta typically consist of a smooth, central iron rich core and an outer layer with chemical asymmetries. The degree of this peripheral asphericity is correlated with the light-curve decline rate of Type Ia supernovae. These observations lend strong support to delayed-detonation models of Type Ia supernovae.

  1. Super Marx Generator for Thermonuclear Ignition

    E-Print Network [OSTI]

    Winterberg, Friedwardt

    2008-01-01T23:59:59.000Z

    In ongoing electric pulse power driven inertial confinement fusion experiments, Marx generators are connected in parallel with the target in the center of a ring of the Marx generators. There the currents, not the voltages add up. Instead of connecting a bank of Marx generator in parallel, one may connect them in series, adding up their voltages, not the currents. If, for example, fifty 20 MV Marx generators are connected in series, they would add up to a gigavolt. But to prevent breakdown, the adding up of the voltages in such a super-Marx generator must be fast. For this reason, it is proposed that each of the Marx generators charges up a fast discharge capacitor, with the thusly charged fast capacitors becoming the elements of a second stage super Marx generator. In a super Marx generator, the Marx generators also assume the role of the resistors in the original Marx circuit. With a voltage of 10^9 Volt and a discharge current of 10^7 Ampere, the generation of a 10^16 Watt GeV proton beam becomes possible,...

  2. The late emission of thermonuclear supernovae

    E-Print Network [OSTI]

    Pilar Ruiz-Lapuente

    1996-04-16T23:59:59.000Z

    The subject of late-time emission of Type Ia supernovae and its implications for the understanding of the explosions of C+O WDs is reviewed.

  3. Dynamic Screening and Thermonuclear Reaction Rates

    E-Print Network [OSTI]

    Andrei V. Gruzinov

    1997-02-06T23:59:59.000Z

    We show that there are no dynamic screening corrections to the Salpeter's enhancement factor in the weak-screening limit.

  4. Analytical Study of Thermonuclear Reaction Probability Integrals

    E-Print Network [OSTI]

    M. A. Chaudhry; H. J. Haubold; A. M. Mathai

    2000-01-16T23:59:59.000Z

    An analytic study of the reaction probability integrals corresponding to the various forms of the slowly varying cross-section factor $S(E)$ is attempted. Exact expressions for reaction probability integrals are expressed in terms of the extended gamma functions.

  5. Deflagrations and Detonations in Thermonuclear Supernovae

    E-Print Network [OSTI]

    Vadim N. Gamezo; Alexei M. Khokhlov; Elaine S. Oran

    2004-06-03T23:59:59.000Z

    We study a type Ia supernova explosion using three-dimensional numerical simulations based on reactive fluid dynamics. We consider a delayed-detonation model that assumes a deflagration-to-detonation transition. In contrast to the pure deflagration model, the delayed-detonation model releases enough energy to account for a healthy explosion, and does not leave carbon, oxygen, and intermediate-mass elements in central parts of a white dwarf. This removes the key disagreement between simulations and observations, and makes a delayed detonation the mostly likely mechanism for type Ia supernovae.

  6. Kawecki et al: Experimental Evolution 1 Experimental Evolution

    E-Print Network [OSTI]

    Alvarez, Nadir

    Kawecki et al: Experimental Evolution 1 Experimental Evolution Tadeusz J. Kawecki1 in Ecology and Evolution, 27: 547560 (2012) Except for a few changes made in proofs, the content of this preprint is identical with the published version of the paper 1 Department of Ecology and Evolution

  7. Internal Control Program

    Broader source: Directives, Delegations, and Requirements [Office of Management (MA)]

    2008-10-28T23:59:59.000Z

    To ensure sound internal controls and overall consistency in exercising the statutory authorities that vest in the Secretary, the Administrator, National Nuclear Security Administration (NNSA), and Department's Chief Financial Officer (CFO), and to implement the Federal Managers' Financial Integrity Act of 1982 and related central agency guidance. Cancels DOE O 413.1A.

  8. International Student Guide

    E-Print Network [OSTI]

    International Student Guide #12;#12;Contents Measures of Quality ...................... 2 No matter Undergraduate programs of study: 250+ majors, minors and concentrations Graduate majors: 100+ Total enrollment-track faculty with doctorate/terminal degrees: 99% 1 #12;Measures of Quality To learn more about Colorado State

  9. Global Network International Relations

    E-Print Network [OSTI]

    Takada, Shoji

    on "Challenges in Organic Materials and Supramolecular Chemistry." The symposium was co-hosted by the Royal twenty-six talks by leading experts in the fields of porous, self-assembled and organic materials; supramolecular chemistry; and sensing and imaging. The 10th International Symposia on Advancing the Chemical

  10. admission guide International

    E-Print Network [OSTI]

    California at Santa Cruz, University of

    Networks Computer Science Computer Science: Computer Game Design Electrical Engineering Communications2015/ 2016 admission guide International First-Year Students #12;2 3 WORLDWIDE RECOGNITION (2008, Science Watch) (2007, Science Watch) (2013, Times Higher Education World University Rankings) (2014, Times

  11. International Pacific Research Center

    E-Print Network [OSTI]

    Wang, Yuqing

    International Pacific Research Center APRIL 2007­MARCH 2008 REPORT School of Ocean and Earth Center i Foreword ii iv Indo-Pacific Ocean Climate 1 Regional-Ocean Influences 13 Asian by the following broad research themes and goals of the IPRC Science Plan. Indo-Pacific Ocean Climate

  12. INTERNATIONAL PACIFIC RESEARCH CENTER

    E-Print Network [OSTI]

    Wang, Yuqing

    INTERNATIONAL PACIFIC RESEARCH CENTER APRIL 2005­MARCH 2006 REPORT SCHOOL OF OCEAN AND EARTH Center 1 The Year's Highlights 3 Indo-Pacific Ocean Climate 4 Regional-Ocean Influences 10 Asian Ocean Climate: To understand climate variations in the Pacific and Indian oceans on interannual

  13. INTERNATIONAL PACIFIC RESEARCH CENTER

    E-Print Network [OSTI]

    Wang, Yuqing

    INTERNATIONAL PACIFIC RESEARCH CENTER Annual Report April 2006 ­ March 2007 School of Ocean Research Center 1 2 The Year's Highlights 3 Research Accomplishments Indo-Pacific Ocean Climate 4 Regional-Ocean Ocean Climate: To understand climate variations in the Pacific and Indian oceans on inter- annual

  14. International energy outlook 1996

    SciTech Connect (OSTI)

    NONE

    1996-05-01T23:59:59.000Z

    This International Energy Outlook presents historical data from 1970 to 1993 and EIA`s projections of energy consumption and carbon emissions through 2015 for 6 country groups. Prospects for individual fuels are discussed. Summary tables of the IEO96 world energy consumption, oil production, and carbon emissions projections are provided in Appendix A. The reference case projections of total foreign energy consumption and of natural gas, coal, and renewable energy were prepared using EIA`s World Energy Projection System (WEPS) model. Reference case projections of foreign oil production and consumption were prepared using the International Energy Module of the National Energy Modeling System (NEMS). Nuclear consumption projections were derived from the International Nuclear Model, PC Version (PC-INM). Alternatively, nuclear capacity projections were developed using two methods: the lower reference case projections were based on analysts` knowledge of the nuclear programs in different countries; the upper reference case was generated by the World Integrated Nuclear Evaluation System (WINES)--a demand-driven model. In addition, the NEMS Coal Export Submodule (CES) was used to derive flows in international coal trade. As noted above, foreign projections of electricity demand are now projected as part of the WEPS. 64 figs., 62 tabs.

  15. Requirements for Xenon International

    SciTech Connect (OSTI)

    Hayes, James C.; Ely, James H.

    2013-09-26T23:59:59.000Z

    This document defines the requirements for the new Xenon International radioxenon system. The output of this project will be a Pacific Northwest National Laboratory (PNNL) developed prototype and a manufacturer-developed production prototype. The two prototypes are intended to be as close to matching as possible; this will be facilitated by overlapping development cycles and open communication between PNNL and the manufacturer.

  16. Experimental Mathematics and Computational Statistics

    SciTech Connect (OSTI)

    Bailey, David H.; Borwein, Jonathan M.

    2009-04-30T23:59:59.000Z

    The field of statistics has long been noted for techniques to detect patterns and regularities in numerical data. In this article we explore connections between statistics and the emerging field of 'experimental mathematics'. These includes both applications of experimental mathematics in statistics, as well as statistical methods applied to computational mathematics.

  17. Building Technologies Experimental Capabilities and Apparatus...

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

    Experimental Capabilities and Apparatus Directory October 01, 2014 ORNL Building Technologies Research and Integration Center (BTRIC) provides unique experimental capabilities...

  18. (Fusion energy research)

    SciTech Connect (OSTI)

    Phillips, C.A. (ed.)

    1988-01-01T23:59:59.000Z

    This report discusses the following topics: principal parameters achieved in experimental devices (FY88); tokamak fusion test reactor; Princeton beta Experiment-Modification; S-1 Spheromak; current drive experiment; x-ray laser studies; spacecraft glow experiment; plasma deposition and etching of thin films; theoretical plasma; tokamak modeling; compact ignition tokamak; international thermonuclear experimental reactor; Engineering Department; Project Planning and Safety Office; quality assurance and reliability; and technology transfer.

  19. International energy indicators. [International and US statistics

    SciTech Connect (OSTI)

    Bauer, E.K. (ed.)

    1980-03-01T23:59:59.000Z

    For the international sector, a table of data is first presented followed by corresponding graph of the data for the following: (1) Iran: crude oil capacity, production, and shut-in, 1974 to February 1980; (2) Saudi Arabia (same as Iran); (3) OPEC (ex-Iran and Saudi Arabia); capacity, production, and shut-in, 1974 to January 1980; (4) non-OPEC Free World and US production of crude oil, 1973 to January 1980; (5) oil stocks: Free World, US, Japan, and Europe (landed), 1973 to 1979; (6) petroleum consumption by industrial countries, 1973 to October 1979; (7) USSR crude oil production, 1974 to February 1980; (8) Free World and US nuclear generation capacity, 1973 to January 1980. For the United States, the same data format is used for the following: (a) US imports of crude oil and products 1973 to January 1980; (b) landed cost of Saudi Arabia crude oil in current and 1974 dollars, 1974 to October 1979; (c) US trade in coal, 1973 to 1979; (d) summary of US merchandise trade, 1976 to January 1980; and (e) US energy/GNP ratio (in 1972 dollars), 1947 to 1979.

  20. International Perspective on Fukushima Accident

    Broader source: Energy.gov [DOE]

    Presenter: Miroslav Lipár, Head, Operational Safety Section, Department of Nuclear Safety and Security, International Atomic Energy Agency

  1. Hanford internal dosimetry program manual

    SciTech Connect (OSTI)

    Carbaugh, E.H.; Sula, M.J.; Bihl, D.E.; Aldridge, T.L.

    1989-10-01T23:59:59.000Z

    This document describes the Hanford Internal Dosimetry program. Program Services include administrating the bioassay monitoring program, evaluating and documenting assessments of internal exposure and dose, ensuring that analytical laboratories conform to requirements, selecting and applying appropriate models and procedures for evaluating internal radionuclide deposition and the resulting dose, and technically guiding and supporting Hanford contractors in matters regarding internal dosimetry. 13 refs., 16 figs., 42 tabs.

  2. International Refrigeration: Order (2012-CE-1510) | Department...

    Energy Savers [EERE]

    International Refrigeration: Order (2012-CE-1510) International Refrigeration: Order (2012-CE-1510) July 20, 2012 DOE ordered International Refrigeration Products to pay an 8,000...

  3. International Fuel Services and Commercial Engagement | Department...

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

    International Fuel Services and Commercial Engagement International Fuel Services and Commercial Engagement The Office of International Nuclear Energy Policy and Cooperation...

  4. International Nuclear Security

    SciTech Connect (OSTI)

    Doyle, James E. [Los Alamos National Laboratory

    2012-08-14T23:59:59.000Z

    This presentation discusses: (1) Definitions of international nuclear security; (2) What degree of security do we have now; (3) Limitations of a nuclear security strategy focused on national lock-downs of fissile materials and weapons; (4) What do current trends say about the future; and (5) How can nuclear security be strengthened? Nuclear security can be strengthened by: (1) More accurate baseline inventories; (2) Better physical protection, control and accounting; (3) Effective personnel reliability programs; (4) Minimize weapons-usable materials and consolidate to fewer locations; (5) Consider local threat environment when siting facilities; (6) Implement pledges made in the NSS process; and (7) More robust interdiction, emergency response and special operations capabilities. International cooperation is desirable, but not always possible.

  5. WORKFLOW SIMULATION FOR INTERNATIONAL TRADE

    E-Print Network [OSTI]

    Thomborson, Clark

    WORKFLOW SIMULATION FOR INTERNATIONAL TRADE Qiang Dong Supervised by Professor Clark Thomborson's competitive world. International trade has received some academic attention as an application of Business Process Reengineering. A major issue in international trade is due to problems pertaining to mutual

  6. MENTAL HEALTH and INTERNATIONAL STUDENTS

    E-Print Network [OSTI]

    MENTAL HEALTH and INTERNATIONAL STUDENTS: What Educators Need to Know Ingle International cares not adequately researched, it is well accepted by health care professionals that early intervention could about you and your students www.studyinsured.com #12;www.studyinsured.comMental Health and International

  7. TOWARDS INTERNATIONAL STANDARDS FOR LANGUAGE

    E-Print Network [OSTI]

    Ide, Nancy

    ) developed by the International Standards Organization TC32 SC4, which is to serve as a basis for harmonizing. It is in this context that a committee of the International Standards Organization (ISO), TC 37/SC 4Chapter # TOWARDS INTERNATIONAL STANDARDS FOR LANGUAGE RESOURCES Nancy Ide and Laurent Romary

  8. TOWARDS INTERNATIONAL STANDARDS FOR LANGUAGE

    E-Print Network [OSTI]

    Boyer, Edmond

    ) developed by the International Standards Organization TC32 SC4, which is to serve as a basis for harmonizingChapter # TOWARDS INTERNATIONAL STANDARDS FOR LANGUAGE RESOURCES Nancy Ide and Laurent Romary-284" #12;2 Chapter # Language Engineering Standards (EAGLES) and the International Standard for Language

  9. INTERNATIONAL JOURNAL OF DEVELOPMENT ISSUES

    E-Print Network [OSTI]

    INTERNATIONAL JOURNAL OF DEVELOPMENT ISSUES VOL. 4 · No. 2 December 2005 CONTENTS Jeffrey D. Sachs-97 and the Bulgarian currency board 95 #12;#12;International Journal of Development Issues Vol. 4, No. 2 (2005) 1 Science, University of Sydney, New South Wales, Australia. #12;J.D. Sachs /International Journal

  10. Polarized internal target apparatus

    DOE Patents [OSTI]

    Holt, R.J.

    1984-10-10T23:59:59.000Z

    A polarized internal target apparatus with a polarized gas target of improved polarization and density (achieved by mixing target gas atoms with a small amount of alkali metal gas atoms, and passing a high intensity polarized light source into the mixture to cause the alkali metal gas atoms to become polarized which interact in spin exchange collisions with target gas atoms yielding polarized target gas atoms) is described.

  11. International petroleum statistics report

    SciTech Connect (OSTI)

    Not Available

    1995-01-01T23:59:59.000Z

    This monthly publication provides current data on international oil production, demand, imports, exports, and stocks. Section 1 contains time series data on world oil production, and on oil demand and stocks in the OECD. Section 2 presents an oil supply/demand balance for the world. Section 3 presents data on oil imports by OECD countries. Section 4 presents annual time series data on world oil production and oil stocks, demand, and trade in OECD countries.

  12. International energy outlook 2006

    SciTech Connect (OSTI)

    NONE

    2006-06-15T23:59:59.000Z

    This report presents international energy projections through 2030, prepared by the Energy Information Administration. After a chapter entitled 'Highlights', the report begins with a review of world energy and economic outlook, followed by energy consumption by end-use sector. The next chapter is on world oil markets. Natural gas, world coal market and electricity consumption and supply are then discussed. The final chapter covers energy-related carbon dioxide emissions.

  13. International markets for CCTs

    SciTech Connect (OSTI)

    Ferriter, J.P. [International Energy Agency, Paris (France)

    1997-12-31T23:59:59.000Z

    The paper begins by describing the role of the International Energy Agency, the importance of coal, what the IEA is doing in the area of clean coal technology, and the role of the IEA Coal Industry Advisory Board. The paper then discusses which coal technologies will be chosen, what the problem areas are, and what can be done to accelerate the take-up of clean coal technologies.

  14. International petroleum statistics report

    SciTech Connect (OSTI)

    NONE

    1997-07-01T23:59:59.000Z

    The International Petroleum Statistics Report is a monthly publication that provides current international data. The report presents data on international oil production, demand, imports, and stocks. The report has four sections. Section 1 contains time series data on world oil production, and on oil demand and stocks in the Organization for Economic Cooperation and Development (OECD). This section contains annual data beginning in 1985, and monthly data for the most recent two years. Section 2 presents an oil supply/demand balance for the world. This balance is presented in quarterly intervals for the most recent two years. Section 3 presents data on oil imports by OECD countries. This section contains annual data for the most recent year, quarterly data for the most recent two quarters, and monthly data for the most recent 12 months. Section 4 presents annual time series data on world oil production and oil stocks, demand, and trade in OECD countries. World oil production and OECD demand data are for the years 1970 through 1996; OECD stocks from 1973 through 1996; and OECD trade from 1986 through 1996.

  15. Internal Audit OverviewInternal Audit Overview Audit's Role in Governance, Risk Management and Internal Control

    E-Print Network [OSTI]

    Buehrer, R. Michael

    Internal Audit OverviewInternal Audit Overview Audit's Role in Governance, Risk Management Activities - Risk Management Scope of Audit Activities - Risk Management · Risk is the possibility exposures to risk, assessing the effectiveness of the University's risk management system, and contributing

  16. Experimental techniques and measurement accuracies

    SciTech Connect (OSTI)

    Bennett, E.F.; Yule, T.J.; DiIorio, G.; Nakamura, T.; Maekawa, H.

    1985-02-01T23:59:59.000Z

    A brief description of the experimental tools available for fusion neutronics experiments is given. Attention is paid to error estimates mainly for the measurement of tritium breeding ratio in simulated blankets using various techniques.

  17. Brussels, May 31, 2005 NOTES Basic 1

    E-Print Network [OSTI]

    and the exploitation of an experimental thermonuclear reactor (ITER) and implementation of the calendar envisaged and the exploitation of an experimental thermonuclear reactor (ITER) and implementation of the calendar envisaged thermonuclear engine. Six parts take part in the negotiations: China, South Korea, the United States, Japan

  18. Course: FUSION SCIENCE AND ENGINEERING Universit degli Studi di Padova

    E-Print Network [OSTI]

    Cesare, Bernardo

    the subject of controlled thermonuclear fusion in magnetically confined plasmas. Both fusion science of Controlled Thermonuclear Fusion, b) Engineering of a Magnetically Confined Fusion Reactor, c) ExperimentalCourse: FUSION SCIENCE AND ENGINEERING Università degli Studi di Padova in agreement

  19. AVTA: 2010 Electric Vehicles International Neighborhood Electric...

    Energy Savers [EERE]

    10 Electric Vehicles International Neighborhood Electric Vehicle Testing Results AVTA: 2010 Electric Vehicles International Neighborhood Electric Vehicle Testing Results The...

  20. Natural System Evaluation and Tool Development: International...

    Energy Savers [EERE]

    Natural System Evaluation and Tool Development: International Collaborations - FY'13 Progress Report Natural System Evaluation and Tool Development: International Collaborations -...

  1. Upcoming Webinar December 16: International Hydrogen Infrastructure...

    Energy Savers [EERE]

    Upcoming Webinar December 16: International Hydrogen Infrastructure Challenges NOW, DOE, and NEDO Upcoming Webinar December 16: International Hydrogen Infrastructure Challenges...

  2. INTERNAL REPAIR OF PIPELINES

    SciTech Connect (OSTI)

    Robin Gordon; Bill Bruce; Ian Harris; Dennis Harwig; Nancy Porter; Mike Sullivan; Chris Neary

    2004-04-12T23:59:59.000Z

    The two broad categories of deposited weld metal repair and fiber-reinforced composite liner repair technologies were reviewed for potential application for internal repair of gas transmission pipelines. Both are used to some extent for other applications and could be further developed for internal, local, structural repair of gas transmission pipelines. Preliminary test programs were developed for both deposited weld metal repair and for fiber-reinforced composite liner repair. Evaluation trials have been conducted using a modified fiber-reinforced composite liner provided by RolaTube and pipe sections without liners. All pipe section specimens failed in areas of simulated damage. Pipe sections containing fiber-reinforced composite liners failed at pressures marginally greater than the pipe sections without liners. The next step is to evaluate a liner material with a modulus of elasticity approximately 95% of the modulus of elasticity for steel. Preliminary welding parameters were developed for deposited weld metal repair in preparation of the receipt of Pacific Gas & Electric's internal pipeline welding repair system (that was designed specifically for 559 mm (22 in.) diameter pipe) and the receipt of 559 mm (22 in.) pipe sections from Panhandle Eastern. The next steps are to transfer welding parameters to the PG&E system and to pressure test repaired pipe sections to failure. A survey of pipeline operators was conducted to better understand the needs and performance requirements of the natural gas transmission industry regarding internal repair. Completed surveys contained the following principal conclusions: (1) Use of internal weld repair is most attractive for river crossings, under other bodies of water, in difficult soil conditions, under highways, under congested intersections, and under railway crossings. (2) Internal pipe repair offers a strong potential advantage to the high cost of horizontal direct drilling (HDD) when a new bore must be created to solve a leak or other problem. (3) Typical travel distances can be divided into three distinct groups: up to 305 m (1,000 ft.); between 305 m and 610 m (1,000 ft. and 2,000 ft.); and beyond 914 m (3,000 ft.). All three groups require pig-based systems. A despooled umbilical system would suffice for the first two groups which represents 81% of survey respondents. The third group would require an onboard self-contained power unit for propulsion and welding/liner repair energy needs. (4) Pipe diameter sizes range from 50.8 mm (2 in.) through 1,219.2 mm (48 in.). The most common size range for 80% to 90% of operators surveyed is 508 mm to 762 mm (20 in. to 30 in.), with 95% using 558.8 mm (22 in.) pipe. An evaluation of potential repair methods clearly indicates that the project should continue to focus on the development of a repair process involving the use of GMAW welding and on the development of a repair process involving the use of fiber-reinforced composite liners.

  3. Internal absorber solar collector

    DOE Patents [OSTI]

    Sletten, Carlyle J. (106 Nagog Hill Rd., Acton, MA 01720); Herskovitz, Sheldon B. (88 Hammond St., Acton, MA 01720); Holt, F. S. (46 Emerson Rd., Winchester, MA 01890); Sletten, E. J. (Chestnut Hill Rd. R.F.D. Rte. #4, Amherst, NH 03031)

    1981-01-01T23:59:59.000Z

    Thin solar collecting panels are described made from arrays of small rod collectors consisting of a refracting dielectric rod lens with an absorber imbedded within it and a reflecting mirror coated on the back side of the dielectric rod. Non-tracking collector panels on vertical walls or roof tops receive approximately 90% of solar radiation within an acceptance zone 60.degree. in elevation angle by 120.degree. or more in the azimuth sectors with a collector concentration ratio of approximately 3.0. Miniaturized construction of the circular dielectric rods with internal absorbers reduces the weight per area of glass, plastic and metal used in the collector panels. No external parts or insulation are needed as heat losses are low due to partial vacuum or low conductivity gas surrounding heated portions of the collector. The miniature internal absorbers are generally made of solid copper with black selective surface and the collected solar heat is extracted at the collector ends by thermal conductivity along the absorber rods. Heat is removed from end fittings by use of liquid circulants. Several alternate constructions are provided for simplifying collector panel fabrication and for preventing the thermal expansion and contraction of the heated absorber or circulant tubes from damaging vacuum seals. In a modified version of the internal absorber collector, oil with temperature dependent viscosity is pumped through a segmented absorber which is now composed of closely spaced insulated metal tubes. In this way the circulant is automatically diverted through heated portions of the absorber giving higher collector concentration ratios than theoretically possible for an unsegmented absorber.

  4. Internal combustion engine

    SciTech Connect (OSTI)

    Evans, H.G.; Speer, S.

    1991-12-31T23:59:59.000Z

    This patent describes improvement in a 2-cycle, diesel cycle internal combustion engine comprising a single in-line engine block, internal wall surfaces defining at least one cylinder within the engine block, the central longitudinal axis of each cylinder being within a common plane extending longitudinally of the engine block, the axially extending internal wall surface of each cylinder being closed at one end and having at least one air intake port therethrough, a piston axially and reciprocally movable within each cylinder over a permitted stroke distance, so as to alternately cover and expose each air intake port for a finite time period; an exhaust port at the closed end of the cylinder above the piston, and a mechanically operated valve for opening and closing such exhaust port located immediately adjacent such port, a substantially rigid connecting rod pivotably connected at one end of each piston, and a crankshaft, rotatably connected to the second end of each connecting rod, such that the crankshaft is caused to rotate connecting means between the piston and the connecting rod. The improvement comprises the diameter of the cylinder is greater than the permitted stroke distance of the piston within the cylinder, and the axis of the crankshaft is parallel to and laterally offset from the common plane by a distance sufficient to form an angle alpha between the connecting rod and the axis of the cylinder, when the piston is at top-dead center, of at least about 12 degrees, such that the time during which each air intake port is exposed is increased when the direction of crankshaft rotation is opposite to the direction of the crankshaft offset from the common plane.

  5. International energy annual 1995

    SciTech Connect (OSTI)

    NONE

    1996-12-01T23:59:59.000Z

    The International Energy Annual presents information and trends on world energy production and consumption for petroleum, natural gas, coal, and electricity. Production and consumption data are reported in standard units as well as British thermal units (Btu). Trade and reserves are shown for petroleum, natural gas, and coal. Data are provided on crude oil refining capacity and electricity installed capacity by type. Prices are included for selected crude oils and for refined petroleum products in selected countries. Population and Gross Domestic Product data are also provided.

  6. International energy outlook 2005

    SciTech Connect (OSTI)

    NONE

    2005-07-01T23:59:59.000Z

    This report presents international energy projections through 2025, prepared by the Energy Information Administration. The outlooks for major energy fuels are discussed, along with electricity, transportation, and environmental issues. After a chapter entitled 'Highlights', the report begins with a review of world energy and an economic outlook. The IEO2005 projections cover a 24 year period. The next chapter is on world oil markets. Natural gas and coal reserves and resources, consumption and trade discussed. The chapter on electricity deals with primary fuel use for electricity generation, and regional developments. The final section is entitled 'Energy-related greenhouse gas emissions'.

  7. International energy annual, 1993

    SciTech Connect (OSTI)

    NONE

    1995-05-08T23:59:59.000Z

    This document presents an overview of key international energy trends for production, consumption, imports, and exports of primary energy commodities in over 200 countries, dependencies, and areas of special sovereignty. Also included are population and gross domestic product data, as well as prices for crude oil and petroleum products in selected countries. Renewable energy includes hydroelectric, geothermal, solar and wind electric power and alcohol for fuel. The data were largely derived from published sources and reports from US Embassy personnel in foreign posts. EIA also used data from reputable secondary sources, industry reports, etc.

  8. International Energy Statistics - EIA

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645 3,625 1,006 492 742EnergyOnItemResearch > The Energy Materials Center at CornellOfvia aEnergyInternational

  9. Sandia Energy - International Leadership

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOE Office of Scienceand RequirementsCoatingsUltra-High-VoltagePower Company'sInAsInternational Leadership Home

  10. NEAC International Subcommittee Recommendations

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645 3,625 1,006 492 742Energy ChinaofSchaeferApril 1,(EAC)TABLEChallenges areNational Defense IndustrialInternational

  11. International energy outlook 1998

    SciTech Connect (OSTI)

    NONE

    1998-04-01T23:59:59.000Z

    The International Energy Outlook 1998 (IEO98) presents an assessment by the Energy Information Administration (EIA) of the outlook for international energy markets through 2020. Projections in IEO98 are displaced according to six basic country groupings. The industrialized region includes projections for four individual countries -- the United States, Canada, Mexico, and Japan -- along with the subgroups Western Europe and Australasia (defined as Australia, New Zealand, and the US Territories). The developing countries are represented by four separate regional subgroups: developing Asia, Africa, Middle East, and Central and South America. China and India are represented in developing Asia. New to this year`s report, country-level projections are provided for Brazil -- which is represented in Central and South America. Eastern Europe and the former Soviet Union (EE/FSU) are considered as a separate country grouping. The report begins with a review of world trends in energy demand. Regional consumption projections for oil, natural gas, coal, nuclear power, and renewable energy (hydroelectricity, geothermal, wind, solar, and other renewables) are presented in five fuel chapters, with a review of the current status of each fuel on a worldwide basis. Summary tables of the IEO98 projections for world energy consumption, carbon emissions, oil production, and nuclear power generating capacity are provided in Appendix A. 88 figs., 77 tabs.

  12. The International Linear Collider

    E-Print Network [OSTI]

    Barish, Barry

    2013-01-01T23:59:59.000Z

    In this article, we describe the key features of the recently completed technical design for the International Linear Collider (ILC), a 200-500 GeV linear electron-positron collider (expandable to 1 TeV) that is based on 1.3 GHz superconducting radio-frequency (SCRF) technology. The machine parameters and detector characteristics have been chosen to complement the Large Hadron Collider physics, including the discovery of the Higgs boson, and to further exploit this new particle physics energy frontier with a precision instrument. The linear collider design is the result of nearly twenty years of R&D, resulting in a mature conceptual design for the ILC project that reflects an international consensus. We summarize the physics goals and capability of the ILC, the enabling R&D and resulting accelerator design, as well as the concepts for two complementary detectors. The ILC is technically ready to be proposed and built as a next generation lepton collider, perhaps to be built in stages beginning as a Hig...

  13. International petroleum statistics report

    SciTech Connect (OSTI)

    NONE

    1995-11-01T23:59:59.000Z

    The International Petroleum Statistics Report presents data on international oil production, demand, imports, exports, and stocks. The report has four sections. Section 1 contains time series data on world oil production, and on oil demand and stocks in the Organization for Economic Cooperation and Development (OECD). This section contains annual data beginning in 1985, and monthly data for the most recent two years. Section 2 presents an oil supply/demand balance for the world. This balance is presented in quarterly intervals for the most recent two years. Section 3 presents data on oil imports by OECD countries. This section contains annual data for the most recent year, quarterly data for the most recent two quarters, and monthly data for the most recent twelve months. Section 4 presents annual time series data on world oil production and oil stocks, demand, and trade in OECD countries. World oil production and OECD demand data are for the years 1970 through 1994; OECD stocks from 1973 through 1994; and OECD trade from 1984 through 1994.

  14. International Clean Energy Coalition

    SciTech Connect (OSTI)

    Erin Skootsky; Matt Gardner; Bevan Flansburgh

    2010-09-28T23:59:59.000Z

    In 2003, the National Association of Regulatory Utility Commissioners (NARUC) and National Energy Technology Laboratories (NETL) collaboratively established the International Clean Energy Coalition (ICEC). The coalition consisting of energy policy-makers, technologists, and financial institutions was designed to assist developing countries in forming and supporting local approaches to greenhouse gas mitigation within the energy sector. ICEC's work focused on capacity building and clean energy deployment in countries that rely heavily on fossil-based electric generation. Under ICEC, the coalition formed a steering committee consisting of NARUC members and held a series of meetings to develop and manage the workplan and define successful outcomes for the projects. ICEC identified India as a target country for their work and completed a country assessment that helped ICEC build a framework for discussion with Indian energy decisionmakers including two follow-on in-country workshops. As of the conclusion of the project in 2010, ICEC had also conducted outreach activities conducted during United Nations Framework Convention on Climate Change (UNFCCC) Ninth Conference of Parties (COP 9) and COP 10. The broad goal of this project was to develop a coalition of decision-makers, technologists, and financial institutions to assist developing countries in implementing affordable, effective and resource appropriate technology and policy strategies to mitigate greenhouse gas emissions. Project goals were met through international forums, a country assessment, and in-country workshops. This project focused on countries that rely heavily on fossil-based electric generation.

  15. Understanding Lustre Internals

    SciTech Connect (OSTI)

    Wang, Feiyi [ORNL; Oral, H Sarp [ORNL; Shipman, Galen M [ORNL; Drokin, Oleg [ORNL; Wang, Di [ORNL; Huang, He [ORNL

    2009-04-01T23:59:59.000Z

    Lustre was initiated and funded, almost a decade ago, by the U.S. Department of Energy (DoE) Office of Science and National Nuclear Security Administration laboratories to address the need for an open source, highly-scalable, high-performance parallel filesystem on by then present and future supercomputing platforms. Throughout the last decade, it was deployed over numerous medium-to-large-scale supercomputing platforms and clusters, and it performed and met the expectations of the Lustre user community. As it stands at the time of writing this document, according to the Top500 list, 15 of the top 30 supercomputers in the world use Lustre filesystem. This report aims to present a streamlined overview on how Lustre works internally at reasonable details including relevant data structures, APIs, protocols and algorithms involved for Lustre version 1.6 source code base. More importantly, it tries to explain how various components interconnect with each other and function as a system. Portions of this report are based on discussions with Oak Ridge National Laboratory Lustre Center of Excellence team members and portions of it are based on our own understanding of how the code works. We, as the authors team bare all responsibilities for all errors and omissions in this document. We can only hope it helps current and future Lustre users and Lustre code developers as much as it helped us understanding the Lustre source code and its internal workings.

  16. Experimental evaluation of gas filled plenum (GFP) insulation for ducts

    E-Print Network [OSTI]

    Walker, Iain S.; Guillot, Cyril

    2003-01-01T23:59:59.000Z

    BOCA. 2003. International Energy Conservation Code. Buildingand International Energy Conservation Code (BOCA 2003)

  17. INTERNAL REPAIR OF PIPELINES

    SciTech Connect (OSTI)

    Bill Bruce; Nancy Porter; George Ritter; Matt Boring; Mark Lozev; Ian Harris; Bill Mohr; Dennis Harwig; Robin Gordon; Chris Neary; Mike Sullivan

    2005-07-20T23:59:59.000Z

    The two broad categories of fiber-reinforced composite liner repair and deposited weld metal repair technologies were reviewed and evaluated for potential application for internal repair of gas transmission pipelines. Both are used to some extent for other applications and could be further developed for internal, local, structural repair of gas transmission pipelines. Principal conclusions from a survey of natural gas transmission industry pipeline operators can be summarized in terms of the following performance requirements for internal repair: (1) Use of internal repair is most attractive for river crossings, under other bodies of water, in difficult soil conditions, under highways, under congested intersections, and under railway crossings. (2) Internal pipe repair offers a strong potential advantage to the high cost of horizontal direct drilling when a new bore must be created to solve a leak or other problem. (3) Typical travel distances can be divided into three distinct groups: up to 305 m (1,000 ft.); between 305 m and 610 m (1,000 ft. and 2,000 ft.); and beyond 914 m (3,000 ft.). All three groups require pig-based systems. A despooled umbilical system would suffice for the first two groups which represents 81% of survey respondents. The third group would require an onboard self-contained power unit for propulsion and welding/liner repair energy needs. (4) The most common size range for 80% to 90% of operators surveyed is 508 mm (20 in.) to 762 mm (30 in.), with 95% using 558.8 mm (22 in.) pipe. Evaluation trials were conducted on pipe sections with simulated corrosion damage repaired with glass fiber-reinforced composite liners, carbon fiber-reinforced composite liners, and weld deposition. Additional un-repaired pipe sections were evaluated in the virgin condition and with simulated damage. Hydrostatic failure pressures for pipe sections repaired with glass fiber-reinforced composite liner were only marginally greater than that of pipe sections without liners, indicating that this type of liner is only marginally effective at restoring the pressure containing capabilities of pipelines. Failure pressures for larger diameter pipe repaired with a semi-circular patch of carbon fiber-reinforced composite lines were also marginally greater than that of a pipe section with un-repaired simulated damage without a liner. These results indicate that fiber reinforced composite liners have the potential to increase the burst pressure of pipe sections with external damage Carbon fiber based liners are viewed as more promising than glass fiber based liners because of the potential for more closely matching the mechanical properties of steel. Pipe repaired with weld deposition failed at pressures lower than that of un-repaired pipe in both the virgin and damaged conditions, indicating that this repair technology is less effective at restoring the pressure containing capability of pipe than a carbon fiber-reinforced liner repair. Physical testing indicates that carbon fiber-reinforced liner repair is the most promising technology evaluated to-date. In lieu of a field installation on an abandoned pipeline, a preliminary nondestructive testing protocol is being developed to determine the success or failure of the fiber-reinforced liner pipeline repairs. Optimization and validation activities for carbon-fiber repair methods are ongoing.

  18. INTERNAL REPAIR OF PIPELINES

    SciTech Connect (OSTI)

    Robin Gordon; Bill Bruce; Ian Harris; Dennis Harwig; George Ritter; Bill Mohr; Matt Boring; Nancy Porter; Mike Sullivan; Chris Neary

    2004-12-31T23:59:59.000Z

    The two broad categories of fiber-reinforced composite liner repair and deposited weld metal repair technologies were reviewed and evaluated for potential application for internal repair of gas transmission pipelines. Both are used to some extent for other applications and could be further developed for internal, local, structural repair of gas transmission pipelines. Principal conclusions from a survey of natural gas transmission industry pipeline operators can be summarized in terms of the following performance requirements for internal repair: (1) Use of internal repair is most attractive for river crossings, under other bodies of water, in difficult soil conditions, under highways, under congested intersections, and under railway crossings. (2) Internal pipe repair offers a strong potential advantage to the high cost of horizontal direct drilling when a new bore must be created to solve a leak or other problem. (3) Typical travel distances can be divided into three distinct groups: up to 305 m (1,000 ft.); between 305 m and 610 m (1,000 ft. and 2,000 ft.); and beyond 914 m (3,000 ft.). All three groups require pig-based systems. A despooled umbilical system would suffice for the first two groups which represents 81% of survey respondents. The third group would require an onboard self-contained power unit for propulsion and welding/liner repair energy needs. (4) The most common size range for 80% to 90% of operators surveyed is 508 mm (20 in.) to 762 mm (30 in.), with 95% using 558.8 mm (22 in.) pipe. Evaluation trials were conducted on pipe sections with simulated corrosion damage repaired with glass fiber-reinforced composite liners, carbon fiber-reinforced composite liners, and weld deposition. Additional un-repaired pipe sections were evaluated in the virgin condition and with simulated damage. Hydrostatic failure pressures for pipe sections repaired with glass fiber-reinforced composite liner were only marginally greater than that of pipe sections without liners, indicating that this type of liner is only marginally effective at restoring the pressure containing capabilities of pipelines. Failure pressures for larger diameter pipe repaired with a semi-circular patch of carbon fiber-reinforced composite lines were also marginally greater than that of a pipe section with un-repaired simulated damage without a liner. These results indicate that fiber reinforced composite liners have the potential to increase the burst pressure of pipe sections with external damage Carbon fiber based liners are viewed as more promising than glass fiber based liners because of the potential for more closely matching the mechanical properties of steel. Pipe repaired with weld deposition failed at pressures lower than that of un-repaired pipe in both the virgin and damaged conditions, indicating that this repair technology is less effective at restoring the pressure containing capability of pipe than a carbon fiber-reinforced liner repair. Physical testing indicates that carbon fiber-reinforced liner repair is the most promising technology evaluated to-date. The first round of optimization and validation activities for carbon-fiber repairs are complete. Development of a comprehensive test plan for this process is recommended for use in the field trial portion of this program.

  19. INTERNAL REPAIR OF PIPELINES

    SciTech Connect (OSTI)

    Robin Gordon; Bill Bruce; Ian Harris; Dennis Harwig; George Ritter; Bill Mohr; Matt Boring; Nancy Porter; Mike Sullivan; Chris Neary

    2004-08-17T23:59:59.000Z

    The two broad categories of fiber-reinforced composite liner repair and deposited weld metal repair technologies were reviewed and evaluated for potential application for internal repair of gas transmission pipelines. Both are used to some extent for other applications and could be further developed for internal, local, structural repair of gas transmission pipelines. Principal conclusions from a survey of natural gas transmission industry pipeline operators can be summarized in terms of the following performance requirements for internal repair: (1) Use of internal repair is most attractive for river crossings, under other bodies of water, in difficult soil conditions, under highways, under congested intersections, and under railway. (2) Internal pipe repair offers a strong potential advantage to the high cost of horizontal direct drilling when a new bore must be created to solve a leak or other problem. (3) Typical travel distances can be divided into three distinct groups: up to 305 m (1,000 ft.); between 305 m and 610 m (1,000 ft. and 2,000 ft.); and beyond 914 m (3,000 ft.). All three groups require pig-based systems. A despooled umbilical system would suffice for the first two groups which represents 81% of survey respondents. The third group would require an onboard self-contained power unit for propulsion and welding/liner repair energy needs. (4) The most common size range for 80% to 90% of operators surveyed is 508 mm (20 in.) to 762 mm (30 in.), with 95% using 558.8 mm (22 in.) pipe. Evaluation trials were conducted on pipe sections with simulated corrosion damage repaired with glass fiber-reinforced composite liners, carbon fiber-reinforced composite liners, and weld deposition. Additional un-repaired pipe sections were evaluated in the virgin condition and with simulated damage. Hydrostatic failure pressures for pipe sections repaired with glass fiber-reinforced composite liner were only marginally greater than that of pipe sections without liners, indicating that this type of liner is only marginally effective at restoring the pressure containing capabilities of pipelines. Failure pressures for larger diameter pipe repaired with a semi-circular patch of carbon fiber-reinforced composite lines were also marginally greater than that of a pipe section with un-repaired simulated damage without a liner. These results indicate that fiber reinforced composite liners have the potential to increase the burst pressure of pipe sections with external damage Carbon fiber based liners are viewed as more promising than glass fiber based liners because of the potential for more closely matching the mechanical properties of steel. Pipe repaired with weld deposition failed at pressures lower than that of un-repaired pipe in both the virgin and damaged conditions, indicating that this repair technology is less effective at restoring the pressure containing capability of pipe than a carbon fiber-reinforced liner repair. Physical testing indicates that carbon fiber-reinforced liner repair is the most promising technology evaluated to-date. Development of a comprehensive test plan for this process is recommended for use in the field trial portion of this program.

  20. Experimental

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOEThe Bonneville Power AdministrationField8,Dist. Category UC-l 1,Energy Consumers | DepartmentProfile: