Science.gov

Sample records for confinement fusion program

  1. Fusion, magnetic confinement

    SciTech Connect

    Berk, H.L.

    1992-08-06

    An overview is presented of the principles of magnetic confinement of plasmas for the purpose of achieving controlled fusion conditions. Sec. 1 discusses the different nuclear fusion reactions which can be exploited in prospective fusion reactors and explains why special technologies need to be developed for the supply of tritium or {sup 3}He, the probable fuels. In Sec. 2 the Lawson condition, a criterion that is a measure of the quality of confinement relative to achieving fusion conditions, is explained. In Sec. 3 fluid equations are used to describe plasma confinement. Specific confinement configurations are considered. In Sec. 4 the orbits of particle sin magneti and electric fields are discussed. In Sec. 5 stability considerations are discussed. It is noted that confinement systems usually need to satisfy stability constraints imposed by ideal magnetohydrodynamic (MHD) theory. The paper culminates with a summary of experimental progress in magnetic confinement. Present experiments in tokamaks have reached the point that the conditions necessary to achieve fusion are being satisfied.

  2. Inertial confinement fusion

    SciTech Connect

    Powers, L.; Condouris, R.; Kotowski, M.; Murphy, P.W.

    1992-01-01

    This issue of the ICF Quarterly contains seven articles that describe recent progress in Lawrence Livermore National Laboratory's ICF program. The Department of Energy recently initiated an effort to design a 1--2 MJ glass laser, the proposed National Ignition Facility (NIF). These articles span various aspects of a program which is aimed at moving forward toward such a facility by continuing to use the Nova laser to gain understanding of NIF-relevant target physics, by developing concepts for an NIF laser driver, and by envisioning a variety of applications for larger ICF facilities. This report discusses research on the following topics: Stimulated Rotational Raman Scattering in Nitrogen; A Maxwell Equation Solver in LASNEX for the Simulation of Moderately Intense Ultrashort Pulse Experiments; Measurements of Radial Heat-Wave Propagation in Laser-Produced Plasmas; Laser-Seeded Modulation Growth on Directly Driven Foils; Stimulated Raman Scattering in Large-Aperture, High-Fluence Frequency-Conversion Crystals; Fission Product Hazard Reduction Using Inertial Fusion Energy; Use of Inertial Confinement Fusion for Nuclear Weapons Effects Simulations.

  3. Inertial Confinement fusion targets

    NASA Technical Reports Server (NTRS)

    Hendricks, C. D.

    1982-01-01

    Inertial confinement fusion (ICF) targets are made as simple flat discs, as hollow shells or as complicated multilayer structures. Many techniques were devised for producing the targets. Glass and metal shells are made by using drop and bubble techniques. Solid hydrogen shells are also produced by adapting old methods to the solution of modern problems. Some of these techniques, problems, and solutions are discussed. In addition, the applications of many of the techniques to fabrication of ICF targets is presented.

  4. Second Review of the Department of Energy's Inertial Confinement Fusion Program

    NASA Astrophysics Data System (ADS)

    1990-09-01

    This report of the second review by the National Research Council of inertial confinement fusion (ICF) contains the appointed committee's final conclusions and recommendations. An interim report was issued in January 1990. The charge to the committee was as follows: determine whether the recommendations of the 1985 NAS review are still appropriate to advance the technology efficaciously. Provide an assessment of the most promising technologies for continuation of the program. Assess the potential contributions of the program under the following scenarios: a comprehensive test ban on underground nuclear testing and prohibition of underground nuclear testing to levels of 1 kiloton, 5 kilotons, and 10 kilotons. Assess the civilian energy potential of ICF. Assess the adequacy of the ICF target performance data base for supporting program plans and decision milestones. Identify major technical and programmatic issues facing the program. Determine the status of each major candidate inertial fusion driver, and specify the critical issues involved in the development of each. Recommend program priorities, particularly with regard to the Centurion/halite program, driver development, and laboratory experiments and theory. Recommend relative priorities of individual support laboratory activities. Examine the strategies and plans of the ICF Program, comment on their soundness, cohesiveness, and programmatic effectiveness, and recommend management initiatives that could improve the progress of the program toward achieving of its goals. The major difference between the 1985 and 1989 reviews is the request for greater attention to the energy potential of the ICF Program and the heavy-ion work being carried out by the Lawrence Berkeley Laboratory at the University of California.

  5. (Experimental development, testing and research work in support of the inertial confinement fusion program)

    SciTech Connect

    Johnson, R.; Luckhardt, R.; Terry, N.; Drake, D.; Gaines, J.

    1990-04-27

    This KMS Fusion Semi-Annual Technical Report covers the period October 1989 through March 1990. It contains a review of work performed by KMS Fusion, Inc. (KMSF), in support of the national program to achieve inertially confined fusion (ICF). A major section of the report is devoted to target technology, a field which is expected to play an increasingly important role in the overall KMSF fusion effort. Among the highlights of our efforts in this area covered in this report are: improvements and new developments in target fabrication techniques, including a discussion of techniques for introducing gaussian bumps and bands on target surfaces. Development of a single automated system for the interferometric characterization of transparent shells. Residual gas analysis of the blowing gases contained in glass shells made from xerogels. These usually include CO{sub 2}, O{sub 2} and N{sub 2}, and are objectionable because they dilute the fuel. Efforts to observe the ice layers formed in the {beta}-layering process in cryogenic targets, and to simulate the formation of these layers. In addition to our work on target technology, we conducted experiments with the Chroma laser and supported the ICF effort at other labs with theoretical and computational support as well as diagnostic development. Included in the work covered in this report are: experiments on Chroma to study interpenetration of and ionization balance in laser generated plasmas. Diagnostic development, including an optical probe for the Aurora laser at Los Alamos National Laboratory, and a high energy x-ray continuum spectrograph for Aurora. Investigation of the radiation cooling instability as a possible mechanism for the generation of relatively cold, dense jets observed in ICF experiments.

  6. Summary of US Fusion Program Planning Documents Relating to Innovative Confinement Concepts (1992-2005)

    NASA Astrophysics Data System (ADS)

    Woodruff, S.

    2007-06-01

    During the 1990's approximately 15 planning documents were produced by community consensus and by panels of experts. These documents lead to the restructuring of the Office of Fusion Energy (OFE). The OFE adopted joint goals of science and performance and opened a solicitation for Innovative Confinement Concept (ICC) experiments. This paper summarizes the documents that appeared during this time that relate to the ICCs.

  7. Magnetic-confinement fusion

    NASA Astrophysics Data System (ADS)

    Ongena, J.; Koch, R.; Wolf, R.; Zohm, H.

    2016-05-01

    Our modern society requires environmentally friendly solutions for energy production. Energy can be released not only from the fission of heavy nuclei but also from the fusion of light nuclei. Nuclear fusion is an important option for a clean and safe solution for our long-term energy needs. The extremely high temperatures required for the fusion reaction are routinely realized in several magnetic-fusion machines. Since the early 1990s, up to 16 MW of fusion power has been released in pulses of a few seconds, corresponding to a power multiplication close to break-even. Our understanding of the very complex behaviour of a magnetized plasma at temperatures between 150 and 200 million °C surrounded by cold walls has also advanced substantially. This steady progress has resulted in the construction of ITER, a fusion device with a planned fusion power output of 500 MW in pulses of 400 s. ITER should provide answers to remaining important questions on the integration of physics and technology, through a full-size demonstration of a tenfold power multiplication, and on nuclear safety aspects. Here we review the basic physics underlying magnetic fusion: past achievements, present efforts and the prospects for future production of electrical energy. We also discuss questions related to the safety, waste management and decommissioning of a future fusion power plant.

  8. Inertial-confinement-fusion targets

    SciTech Connect

    Hendricks, C.D.

    1981-11-16

    Inertial confinement fusion (ICF) targets are made as simple flat discs, as hollow shells or as complicated multilayer structures. Many techniques have been devised for producing the targets. Glass and metal shells are made by using drop and bubble techniques. Solid hydrogen shells are also produced by adapting old methods to the solution of modern problems. Some of these techniques, problems and solutions are discussed. In addition, the applications of many of the techniques to fabrication of ICF targets is presented.

  9. Multishell inertial confinement fusion target

    DOEpatents

    Holland, James R.; Del Vecchio, Robert M.

    1987-01-01

    A method of fabricating multishell fuel targets for inertial confinement fusion usage. Sacrificial hemispherical molds encapsulate a concentric fuel pellet which is positioned by fiber nets stretched tautly across each hemispherical mold section. The fiber ends of the net protrude outwardly beyond the mold surfaces. The joint between the sacrificial hemispheres is smoothed. A ceramic or glass cover is then deposited about the finished mold surfaces to produce an inner spherical surface having continuously smooth surface configuration. The sacrificial mold is removed by gaseous reactions accomplished through the porous ceramic cover prior to enclosing of the outer sphere by addition of an outer coating. The multishell target comprises the inner fuel pellet concentrically arranged within a surrounding coated cover or shell by fiber nets imbedded within the cover material.

  10. Multishell inertial confinement fusion target

    DOEpatents

    Holland, James R.; Del Vecchio, Robert M.

    1984-01-01

    A method of fabricating multishell fuel targets for inertial confinement fusion usage. Sacrificial hemispherical molds encapsulate a concentric fuel pellet which is positioned by fiber nets stretched tautly across each hemispherical mold section. The fiber ends of the net protrude outwardly beyond the mold surfaces. The joint between the sacrificial hemispheres is smoothed. A ceramic or glass cover is then deposited about the finished mold surfaces to produce an inner spherical surface having continuously smooth surface configuration. The sacrificial mold is removed by gaseous reaction accomplished through the porous ceramic cover prior to enclosing of the outer sphere by addition of an outer coating. The multishell target comprises the inner fuel pellet concentrically arranged within a surrounding coated cover or shell by fiber nets imbedded within the cover material.

  11. The LLNL (Lawrence Livermore National Laboratory) ICF (Inertial Confinement Fusion) Program: Progress toward ignition in the Laboratory

    SciTech Connect

    Storm, E.; Batha, S.H.; Bernat, T.P.; Bibeau, C.; Cable, M.D.; Caird, J.A.; Campbell, E.M.; Campbell, J.H.; Coleman, L.W.; Cook, R.C.; Correll, D.L.; Darrow, C.B.; Davis, J.I.; Drake, R.P.; Ehrlich, R.B.; Ellis, R.J.; Glendinning, S.G.; Haan, S.W.; Haendler, B.L.; Hatcher, C.W.; Hatchett, S.P.; Hermes, G.L.; Hunt, J.P.; Kania, D.R.; Kauffman, R.L.; Kilkenny, J.D.; Kornblum, H.N.; Kruer, W.L.; Kyrazis, D.T.; Lane, S.M.; Laumann

    1990-10-02

    The Inertial Confinement Fusion (ICF) Program at the Lawrence Livermore National Laboratory (LLNL) has made substantial progress in target physics, target diagnostics, and laser science and technology. In each area, progress required the development of experimental techniques and computational modeling. The objectives of the target physics experiments in the Nova laser facility are to address and understand critical physics issues that determine the conditions required to achieve ignition and gain in an ICF capsule. The LLNL experimental program primarily addresses indirect-drive implosions, in which the capsule is driven by x rays produced by the interaction of the laser light with a high-Z plasma. Experiments address both the physics of generating the radiation environment in a laser-driven hohlraum and the physics associated with imploding ICF capsules to ignition and high-gain conditions in the absence of alpha deposition. Recent experiments and modeling have established much of the physics necessary to validate the basic concept of ignition and ICF target gain in the laboratory. The rapid progress made in the past several years, and in particular, recent results showing higher radiation drive temperatures and implosion velocities than previously obtained and assumed for high-gain target designs, has led LLNL to propose an upgrade of the Nova laser to 1.5 to 2 MJ (at 0.35 {mu}m) to demonstrate ignition and energy gains of 10 to 20 -- the Nova Upgrade.

  12. April 1999 highlights of the pulsed power inertial confinement fusion program.

    SciTech Connect

    Sweeney, Mary Ann

    1999-06-01

    In April they received a DOE Defense Programs award for significant contributions to the Nuclear Weapons Program in developing and applying z-pinch x-ray sources to stockpile stewardship. DOE also recognized pulsed power for outstanding performance at a world-class level as part of the FY98 performance appraisal review. There were 13 Z shots: 3 for LANL weapon physics, 2 to prepare to measure the D{sub 2} equation of state (EOS), 4 to assess energetics of single-sided drive with the z-pinch-driven hohlraum, and 4 to study the variation in x-ray power with the mass of a copper converter foil inside a nested wire array for the dynamic hohlraum.

  13. Inertial Confinement Fusion Materials Science

    SciTech Connect

    Hamza, A V

    2004-06-01

    Demonstration of thermonuclear ignition and gain on a laboratory scale is one of science's grand challenges. The National Ignition Facility (NIF) is committed to achieving inertial confinement fusion (ICF) by 2010. Success in this endeavor depends on four elements: the laser driver performance, target design, experimental diagnostics performance, and target fabrication and target materials performance. This article discusses the current state of target fabrication and target materials performance. The first three elements will only be discussed insofar as they relate to target fabrication specifications and target materials performance. Excellent reviews of the physics of ICF are given by Lindl [Lindl 1998] and Lindl et al. [Lindl 2004]. To achieve conditions under which inertial confinement is sufficient to achieve thermonuclear burn, an imploded fuel capsule is compressed to conditions of high density and temperature. In the laboratory a driver is required to impart energy to the capsule to effect an implosion. There are three drivers currently being considered for ICF in the laboratory: high-powered lasers, accelerated heavy ions, and x rays resulting from pulsed power machines. Of these, high-powered lasers are the most developed, provide the most symmetric drive, and provide the most energy. Laser drive operates in two configurations. The first is direct drive where the laser energy impinges directly on the ICF capsule and drives the implosion. The second is indirect drive, where the energy from the laser is first absorbed in a high-Z enclosure or hohlraum surrounding the capsule, and the resulting x-rays emitted by the hohlraum material drives the implosion. Using direct drive the laser beam energy is absorbed by the electrons in the outer corona of the target. The electrons transport the energy to the denser shell region to provide the ablation and the resulting implosion. Laser direct drive is generally less efficient and more hydrodynamically unstable than

  14. Review of Inertial Confinement Fusion

    NASA Astrophysics Data System (ADS)

    Haines, M. G.

    The physics of inertial confinement fusion is reviewed. The trend to short-wavelength lasers is argued, and the distinction between direct and indirect (soft X-ray) drive is made. Key present issues include the non-linear growth of Rayleigh-Taylor (R-T) instabilities, the seeding of this instability by the initial laser imprint, the relevance of self-generated magnetic fields, and the importance of parametric instabilities (stimulated Brillouin and Raman scattering) in gas-filled hohlraums. Experiments are reviewed which explore the R-T instability in both planar and converging geometry. The employment of various optical smoothing techniques is contrasted with the overcoating of the capsule by gold coated plastic foams to reduce considerably the imprint problem. The role of spontaneously generated magnetic fields in non-symmetric plasmas is discussed. Recent hohlraum compression results are presented together with gas bag targets which replicate the long-scale-length low density plasmas expected in NIF gas filled hohlraums. The onset of first Brillouin and then Raman scattering is observed. The fast ignitor scheme is a proposal to use an intense short pulse laser to drill a hole through the coronal plasma and then, with laser excited fast electrons, create a propagating thermonuclear spark in a dense, relatively cold laser-compressed target. Some preliminary results of laser hole drilling and 2-D and 3-D PIC simulations of this and the > 10^8 Gauss self-generated magnetic fields are presented. The proposed National Ignition Facility (NIF) is described.

  15. National Ignition Facility for Inertial Confinement Fusion

    SciTech Connect

    Paisner, J.A.; Murray, J.R.

    1997-10-08

    The National Ignition Facility for inertial confinement fusion will contain a 1.8 MJ, 500 TW frequency-tripled neodymium glass laser system that will be used to explore fusion ignition and other problems in the physics of high temperature and density. We describe the facility briefly. The NIF is scheduled to be completed in 2003.

  16. Inertial-confinement fusion with lasers

    NASA Astrophysics Data System (ADS)

    Betti, R.; Hurricane, O. A.

    2016-05-01

    The quest for controlled fusion energy has been ongoing for over a half century. The demonstration of ignition and energy gain from thermonuclear fuels in the laboratory has been a major goal of fusion research for decades. Thermonuclear ignition is widely considered a milestone in the development of fusion energy, as well as a major scientific achievement with important applications in national security and basic sciences. The US is arguably the world leader in the inertial confinement approach to fusion and has invested in large facilities to pursue it, with the objective of establishing the science related to the safety and reliability of the stockpile of nuclear weapons. Although significant progress has been made in recent years, major challenges still remain in the quest for thermonuclear ignition via laser fusion. Here, we review the current state of the art in inertial confinement fusion research and describe the underlying physical principles.

  17. Inertial confinement fusion at the Los Alamos National Laboratory

    SciTech Connect

    Lindman, E.; Baker, D.; Barnes, C.; Bauer, B.; Beck, J.B.

    1997-11-01

    The Los Alamos National Laboratory is contributing to the resolution of key issues in the US Inertial-Confinement-Fusion Program and plans to play a strong role in the experimental program at the National Ignition Facility when it is completed.

  18. Inertial Confinement Fusion Program at Lawrence Livermore National Laboratory:. The National Ignition Facility, Inertial Fusion Energy, 100-1000 TW Lasers, and the Fast Igniter Concept

    NASA Astrophysics Data System (ADS)

    Howard Lowdermilk, W.

    The ultimate goal of worldwide research in inertial confinement fusion (ICF) is to develop fusion as an inexhaustible, economic, environmentally safe source of electric power. Following nearly thirty years of laboratory and underground fusion experiments, the next step toward this goal is to demonstrate ignition and propagating burn of fusion fuel in the laboratory. The National Ignition Facility (NIF) Project is being constructed at Lawrence Livermore National Laboratory (LLNL) for just this purpose. NIF will use advanced Nd-glass laser technology to deliver 1.8 MJ of 0.35 μm laser light in a shaped pulse, several nanoseconds in duration, achieving a peak power of 500 TW. A national community of U.S. laboratories is participating in this project, now in its final design phase. France and the United Kingdom are collaborating on development of required technology under bilateral agreements with the US. This paper presents key aspects of the laser design, and descriptions of principal laser and optical components. Follow-on development of lasers to meet the demands of an inertial fusion energy (IFE) power plant is reviewed. In parallel with the NIF Project and IFE developments, work is proceeding on ultrashort pulse lasers with peak power in the range of 100-1000 TW. A beamline on the Nova laser at LLNL recently delivered nearly 600 J of 1 μm light in a 0.5 ps duration pulse, for a peak power in excess of a petawatt (1015 W). This beamline, with advanced adaptive optics, will be capable of focused intensities in excess of 1021 W/cm2. Its primary purpose will be to test technological and scientific aspects of an alternate ignition concept, called the "Fast Igniter", that has the potential to produce higher fusion gain than conventional ICF.

  19. Nuclear diagnostics for inertial confinement fusion implosions

    SciTech Connect

    Murphy, T.J.

    1997-11-01

    This abstract contains viewgraphs on nuclear diagnostic techniques for inertial confinement fusion implosions. The viewgraphs contain information on: reactions of interest in ICF; advantages and disadvantages of these methods; the properties nuclear techniques can measure; and some specifics on the detectors used.

  20. Initial progress in the first wall, blanket, and shield Engineering Test Program for magnetically confined fusion-power reactors

    SciTech Connect

    Herman, H.; Baker, C.C.; Maroni, V.A.

    1981-10-01

    The first wall/blanket/shield (FW/B/S) Engineering Test Program (ETP) progressed from the planning stage into implementation during July, 1981. The program, generic in nature, comprises four Test Program Elements (TPE's), the emphasis of which is on defining the performance parameters for the Fusion Engineering Device (FED) and the major fusion device to follow FED. These elements are: (1) nonnuclear thermal-hydraulic and thermomechanical testing of first wall and component facsimiles with emphasis on surface heat loads and heat transient (i.e., plasma disruption) effects; (2) nonnuclear and nuclear testing of FW/B/S components and assemblies with emphasis on bulk (nuclear) heating effects, integrated FW/B/S hydraulics and mechanics, blanket coolant system transients, and nuclear benchmarks; (3) FW/B/S electromagnetic and eddy current effects testing, including pulsed field penetration, torque and force restraint, electromagnetic materials, liquid metal MHD effects and the like; and (4) FW/B/S Assembly, Maintenance and Repair (AMR) studies focusing on generic AMR criteria, with the objective of preparing an AMR designers guidebook; also, development of rapid remote assembly/disassembly joint system technology, leak detection and remote handling methods.

  1. Generalized Lawson Criteria for Inertial Confinement Fusion

    SciTech Connect

    Tipton, Robert E.

    2015-08-27

    The Lawson Criterion was proposed by John D. Lawson in 1955 as a general measure of the conditions necessary for a magnetic fusion device to reach thermonuclear ignition. Over the years, similar ignition criteria have been proposed which would be suitable for Inertial Confinement Fusion (ICF) designs. This paper will compare and contrast several ICF ignition criteria based on Lawson’s original ideas. Both analytical and numerical results will be presented which will demonstrate that although the various criteria differ in some details, they are closely related and perform similarly as ignition criteria. A simple approximation will also be presented which allows the inference of each ignition parameter directly from the measured data taken on most shots fired at the National Ignition Facility (NIF) with a minimum reliance on computer simulations. Evidence will be presented which indicates that the experimentally inferred ignition parameters on the best NIF shots are very close to the ignition threshold.

  2. Summary of progress in inertial confinement fusion

    SciTech Connect

    Younger, S.M.

    1992-12-31

    Progress in inertial confinement fusion (ICF) has been very rapid over the past two years. Significant advances have been made in the production of smooth laser beams, the focusing of light ions beams, and the development of heavy ion accelerators. The availability of advanced target diagnostics on several major drivers has resulted in an extensive database of target performance over a wide range of conditions. Theoretical models of ICF targets are approaching the predictive level with two and even three dimensional calculations becoming routine. Within the next several years information should be available to allow confident extrapolation to ignition on the next generation driver.

  3. Summary of progress in inertial confinement fusion

    SciTech Connect

    Younger, S.M.

    1992-01-01

    Progress in inertial confinement fusion (ICF) has been very rapid over the past two years. Significant advances have been made in the production of smooth laser beams, the focusing of light ions beams, and the development of heavy ion accelerators. The availability of advanced target diagnostics on several major drivers has resulted in an extensive database of target performance over a wide range of conditions. Theoretical models of ICF targets are approaching the predictive level with two and even three dimensional calculations becoming routine. Within the next several years information should be available to allow confident extrapolation to ignition on the next generation driver.

  4. Diamond Ablators for Inertial Confinement Fusion

    SciTech Connect

    Biener, J; Mirkarimi, P B; Tringe, J W; Baker, S L; Wang, Y M; Kucheyev, S O; Teslich, N E; Wu, K J; Hamza, A V; Wild, C; Woerner, E; Koidl, P; Bruehne, K; Fecht, H

    2005-06-21

    Diamond has a unique combination of physical properties for the inertial confinement fusion ablator application, such as appropriate optical properties, high atomic density, high yield strength, and high thermal conductivity. Here, we present a feasible concept to fabricate diamond ablator shells. The fabrication of diamond capsules is a multi-step process, which involves diamond chemical vapor deposition on silicon mandrels followed by polishing, microfabrication of holes, and removing of the silicon mandrel by an etch process. We also discuss the pros and cons of coarse-grained optical quality and nanocrystalline chemical vapor deposition diamond films for the ablator application.

  5. Micromachining of inertial confinement fusion targets

    SciTech Connect

    Gobby, P.L.; Salzer, L.J.; Day, R.D.

    1996-12-31

    Many experiments conducted on today`s largest inertial confinement fusion drive lasers require target components with sub-millimeter dimensions, precisions of a micron or less and surface finishes measured in nanometers. For metal and plastic, techniques using direct machining with diamond tools have been developed that yield the desired parts. New techniques that will be discussed include the quick-flip locator, a magnetically held kinematic mount that has allowed the direct machining of millimeter-sized beryllium hemishells whose inside and outside surface are concentric to within 0.25 micron, and an electronic version of a tracer lathe which has produced precise azimuthal variations of less than a micron.

  6. Deceleration Phase of Inertial Confinement Fusion Implosions

    NASA Astrophysics Data System (ADS)

    Betti, R.

    2001-10-01

    In inertial confinement fusion (ICF) implosions, a spherical shell of cryogenic deuterium and tritium (DT) filled with DT gas is accelerated by direct laser irradiation (direct drive) or x-rays produced by a high-Z enclosure (indirect drive). Hydrodynamic instabilities, growing on the outer shell surface during the acceleration phase, cause the outer nonuniformities to feed through the shell onto the inner surface. As the shell starts to decelerate, the inner surface is unstable to the Rayleigh-Taylor instability and the inner surface nonuniformities grow exponentially in time, causing the cold shell material to penetrate and cool the hot spot. Such a cooling could prevent the hot spot from achieving the ignition conditions. We have developed a model to study the deceleration phase of imploding capsules, including the onset of ignition. The model yields all the hot-spot profiles and the hydrodynamic parameters of interest to the deceleration phase instability: ablation velocity [Ref.1] off the shell's inner surface, density-gradient scale length, and deceleration. It is shown [Ref. 1] that the growth rates of the deceleration-phase instability are significantly reduced by the finite ablative flow and the unstable spectrum exhibits a cutoff at short wavelengths. For a direct-drive NIF-like capsule, the cutoff mode number occurs for l ~= 90. The marginal ignition scaling law of Ref. 2 is also recovered analytically. This work was supported by the U.S. Department of Energy Office of Inertial Confinement Fusion under Cooperative Agreement No. DE-FC03-92SF19460. [1] V. Lobatchev and R. Betti, Phys. Rev. Lett. 85, 4522 (2000); [2] M. C. Herrmann, M. Tabak, and J. D. Lindl, Nucl. Fusion 41, 99 (2001).

  7. Stellarator approach to fusion plasma confinement

    SciTech Connect

    Harris, J.H.

    1985-01-01

    The stellarator is a toroidal fusion plasma confinement device with nested magnetic flux surfaces. The required twist of the field lines is produced by external helical coils rather than by plasma current, as in a tokamak. Stellarator devices are attractive fusion reactor candidates precisely because they offer the prospect of steady-state operation without plasma current. In the last few years the excellent results achieved with currentless stellarator plasmas of modest minor radius (10 to 20 cm) at Kyoto University (Japan) and the Max Planck Institute (West Germany) have made the stellarator second only to the tokamak in its progress toward fusion breakeven, with temperatures T/sub e/, T/sub i/ approx. 1 KeV, Lawson products n tau approx. 2 to 5 x 10/sup 12/ cm/sup -3/.s, and volume-averaged beta values approx. = 2%. The Advanced Toroidal Facility (ATF), now under construction at Oak Ridge Natioal Laboratory (ORNL) and scheduled to operate in 1986, represents a significant advance in stellarator research, with a plasma major radius of 2.1 m, an average minor radius of 0.3 m, and a magnetic field of 2 T for 5 s or 1 T at steady state. ATF replaces the Impurity Study Experiment (ISX-B) tokamak at ORNL and will use the ISX-B heating and diagnostic system.

  8. COLLABORATIVE: FUSION SIMULATION PROGRAM

    SciTech Connect

    Chang, Choong Seock

    2012-06-05

    New York University, Courant Institute of Mathematical Sciences, participated in the “Fusion Simulation Program (FSP) Planning Activities” [http://www.pppl.gov/fsp], with C.S. Chang as the institutional PI. FSP’s mission was to enable scientific discovery of important new plasma phenomena with associated understanding that emerges only upon integration. This requires developing a predictive integrated simulation capability for magnetically-confined fusion plasmas that are properly validated against experiments in regimes relevant for producing practical fusion energy. Specific institutional goal of the New York University was to participate in the planning of the edge integrated simulation, with emphasis on the usage of large scale HPCs, in connection with the SciDAC CPES project which the PI was leading. New York University successfully completed its mission by participating in the various planning activities, including the edge physics integration, the edge science drivers, and the mathematical verification. The activity resulted in the combined report that can be found in http://www.pppl.gov/fsp/Overview.html. Participation and presentations as part of this project are listed in a separation file.

  9. Inertial Confinement Fusion quarterly report, April--June 1995. Volume 5, No. 3

    SciTech Connect

    1995-12-31

    The ICF Quarterly Reports is published four times each fiscal year by the Inertial Confinement Fusion Program at the Lawrence Livermore National Laboratory. The journal reports selected current research within the ICF Program. Major areas of investigation presented here include fusion target theory and design, target fabrication, target experiments, and laser and optical science and technology.

  10. Inertial confinement fusion with light ion beams.

    PubMed

    Vandevender, J P; Cook, D L

    1986-05-16

    The Particle Beam Fusion Accelerator II (PBFA II) is presently under construction and is the only existing facility with the potential of igniting thermonuclear fuel in the laboratory. The accelerator will generate up to 5 megamperes of lithium ions at 30 million electron volts and will focus them onto an inertial confinement fusion (ICF) target after beam production and focusing have been optimized. Since its inception, the light ion approach to ICF has been considered the one that combines low cost, high risk, and high payoff. The beams are of such high density that their self-generated electric and magnetic fields were thought to prohibit high focal intensities. Recent advances in beam production and focusing demonstrate that these self-forces can be controlled to the degree required for ignition, break-even, and high gain experiments. ICF has been pursued primarily for its potential military applications. However, the high efficiency and cost-effectiveness of the light ion approach enhance its potential for commercial energy application as well. PMID:17755963

  11. Inertial Confinement Fusion Annual Report 1997

    SciTech Connect

    Correll, D

    1998-06-01

    The ICF Annual Report provides documentation of the achievements of the LLNL ICF Program during the fiscal year by the use of two formats: (1) an Overview that is a narrative summary of important results for the fiscal year and (2) a compilation of the articles that previously appeared in the ICF Quarterly Report that year. Both the Overview and Quarterly Report are also on the Web at http://lasers.llnl.gov/lasers/pubs/icfq.html. Beginning in Fiscal Year 1997, the fourth quarter issue of the ICF Quarterly was no longer printed as a separate document but rather included in the ICF Annual. This change provided a more efficient process of documenting our accomplishments with-out unnecessary duplication of printing. In addition we introduced a new document, the ICF Program Monthly Highlights. Starting with the September 1997 issue and each month following, the Monthly Highlights will provide a brief description of noteworthy activities of interest to our DOE sponsors and our stakeholders. The underlying theme for LLNL's ICF Program research continues to be defined within DOE's Defense Programs missions and goals. In support of these missions and goals, the ICF Program advances research and technology development in major interrelated areas that include fusion target theory and design, target fabrication, target experiments, and laser and optical science and technology. While in pursuit of its goal of demonstrating thermonuclear fusion ignition and energy gain in the laboratory, the ICF Program provides research and development opportunities in fundamental high-energy-density physics and supports the necessary research base for the possible long-term application of inertial fusion energy for civilian power production. ICF technologies continue to have spin-off applications for additional government and industrial use. In addition to these topics, the ICF Annual Report covers non-ICF funded, but related, laser research and development and associated applications. We also

  12. Inertial Confinement Fusion quarterly report, January--March 1995. Volume 5, No. 2

    SciTech Connect

    1995-09-01

    The ICF quarterly report is published by the Inertial Confinement Fusion Program at the Lawrence Livermore National Laboratory. Topics included this quarter include: the role of the National Ignition Facility in the development of Inertial Confinement Fusion, laser-plasma interactions in large gas-filled hohlraums, evolution of solid-state induction modulators for a heavy-ion recirculator, the National Ignition Facility project, and terminal-level relaxation in Nd-doped laser material.

  13. Planar geometry inertial electrostatic confinement fusion device

    NASA Astrophysics Data System (ADS)

    Knapp, Daniel R.

    2015-03-01

    In the classic gridded inertial electrostatic confinement (IEC) fusion reactor, ion bombardment of the grid leads to heating, thermionic electron emission, significant power loss, and ultimately melting of the grid. Gridless IEC devices have sought to overcome these limitations. Klein reported a gridless device in which ions are circulated as a linear beam in an electrostatic analogue of an optical resonator. To overcome limits of stored ions due to space charge effects at the turning regions, the device employed multiple overlapping traps. The work reported here seeks to further increase the turning region space in a gridless trap by employing a planar geometry. Ion trapping in the planar device was examined by simulating trajectories of 2H+ ions with SIMION 8.1 software. Simulations were carried out using multiple potentials as in Klein's device and for a single potential trap as a planar analogue of the anharmonic ion trap. Scattering by background gas was simulated using a hard sphere collision model, and the results suggested the device will require operation at low pressure with a separate ion source.

  14. Auxiliary Heating of Inertial Confinement Fusion Targets

    NASA Astrophysics Data System (ADS)

    Norreys, Peter

    2014-10-01

    The role of collisionless ion heating arising from the propagation of petawatt-laser driven relativistic electron beams in dense plasma will be discussed. The energy cascade mechanism begins first with the rapid growth of electrostatic waves near the electron plasma frequency. These waves reach high amplitudes and break, which then results in the generation of a strongly driven turbulent Langmuir spectrum. Parametric decay of these waves, particularly via the modulational instability, then gives rise to a coupled turbulent ion acoustic spectrum. These waves, in turn, experience significant Landau damping, resulting in the rapid heating of the background ion population. In this talk, I will review the evidence for this cascade process in laboratory plasmas and describe the theoretical background that underpins this process. I will then present the most recent analytic modelling, particle-in-cell and Vlasov-Poisson simulation results of my team within Oxford Physics and the Central Laser Facility that explores the optimum parameter space for this process, focusing in particular on the requirements for auxiliary heating of the central hot spot in inertial confinement fusion target experiments now underway on the National Ignition Facility. I will also describe new methods for hole-boring through the coronal plasma surrounding the fuel using strongly relativistic laser beams that demonstrates the strong suppression of the hosing instability under these conditions.

  15. Target fabrication for inertial confinement fusion research

    NASA Astrophysics Data System (ADS)

    Mah, Richard; Duchane, David V.; Young, Ainslie T.; Rhorer, Richard L.

    1985-05-01

    The design of both laser fusion and particle beam fusion targets has become increasingly more complex with greater demands on both target tolerances and the physical and mechanical properties of target materials. The Materials Technology Group at Los Alamos has been given the responsibility for fabricating these targets. In order to meet the demands of the ICF program, the target fabrication effort maintains a wide variety of processes to provide metallic, non-metallic and composite materials for target components. These processes are also geared to provide superior surface finishes, wall uniformity and, in the case of metals, a fine grained equiaxed structure. The materials technologies that will be described include chemical vapor deposition (CVD), physical vapor deposition (PVD), electrochemical deposition, vapor phase pyrolysis (VPP), low pressure plasma coating (LPP) and the sorption/diffusion (SD) process. This paper will also discuss the materials and the material properties that can be obtained by these processes. The result of maintaining all these technologies and processes is to allow the greatest latitude for ICF target designers.

  16. Thomson scattering from inertial confinement fusion plasmas

    SciTech Connect

    Glenzer, S.H.; Back, C.A.; Suter, L.J.

    1997-07-08

    Thomson scattering has been developed at the Nova laser facility as a direct and accurate diagnostic to characterize inertial confinement fusion plasmas. Flat disks coated with thin multilayers of gold and beryllium were with one laser beam to produce a two ion species plasma with a controlled amount of both species. Thomson scattering spectra from these plasmas showed two ion acoustic waves belonging to gold and beryllium. The phase velocities of the ion acoustic waves are shown to be a sensitive function of the relative concentrations of the two ion species and are in good agreement with theoretical calculations. These open geometry experiments further show that an accurate measurement of the ion temperature can be derived from the relative damping of the two ion acoustic waves. Subsequent Thomson scattering measurements from methane-filled, ignition-relevant hohlraums apply the theory for two ion species plasmas to obtain the electron and ion temperatures with high accuracy. The experimental data provide a benchmark for two-dimensional hydrodynamic simulations using LASNEX, which is presently in use to predict the performance of future megajoule laser driven hohlraums of the National Ignition Facility (NIF). The data are consistent with modeling using significantly inhibited heat transport at the peak of the drive. Applied to NIF targets, this flux limitation has little effect on x- ray production. The spatial distribution of x-rays is slightly modified but optimal symmetry can be re-established by small changes in power balance or pointing. Furthermore, we find that stagnating plasma regions on the hohlraum axis are well described by the calculations. This result implies that stagnation in gas-filled hohlraums occurs too late to directly affect the capsule implosion in ignition experiments.

  17. Massachusetts Institute of Technology, Plasma Fusion Center, Technical Research Programs

    SciTech Connect

    Davidson, Ronald C.

    1980-08-01

    A review is given of the technical programs carried out by the Plasma Fusion Center. The major divisions of work areas are applied plasma research, confinement experiments, fusion technology and engineering, and fusion systems. Some objectives and results of each program are described. (MOW)

  18. KULL: LLNL's ASCI Inertial Confinement Fusion Simulation Code

    SciTech Connect

    Rathkopf, J. A.; Miller, D. S.; Owen, J. M.; Zike, M. R.; Eltgroth, P. G.; Madsen, N. K.; McCandless, K. P.; Nowak, P. F.; Nemanic, M. K.; Gentile, N. A.; Stuart, L. M.; Keen, N. D.; Palmer, T. S.

    2000-01-10

    KULL is a three dimensional, time dependent radiation hydrodynamics simulation code under development at Lawrence Livermore National Laboratory. A part of the U.S. Department of Energy's Accelerated Strategic Computing Initiative (ASCI), KULL's purpose is to simulate the physical processes in Inertial Confinement Fusion (ICF) targets. The National Ignition Facility, where ICF experiments will be conducted, and ASCI are part of the experimental and computational components of DOE's Stockpile Stewardship Program. This paper provides an overview of ASCI and describes KULL, its hydrodynamic simulation capability and its three methods of simulating radiative transfer. Particular emphasis is given to the parallelization techniques essential to obtain the performance required of the Stockpile Stewardship Program and to exploit the massively parallel processor machines that ASCI is procuring.

  19. Computer modeling and simulation in inertial confinement fusion

    NASA Astrophysics Data System (ADS)

    McCrory, R. L.; Verdon, C. P.

    1989-03-01

    The complex hydrodynamic and transport processes associated with the implosion of an inertial confinement fusion (ICF) pellet place considerable demands on numerical simulation programs. Processes associated with implosion can usually be described using relatively simple models, but their complex interplay requires that programs model most of the relevant physical phenomena accurately. Most hydrodynamic codes used in ICF incorporate a one-fluid, two-temperature model. Electrons and ions are assumed to flow as one fluid (no charge separation). Due to the relatively weak coupling between the ions and electrons, each species is treated separately in terms of its temperature. In this paper we describe some of the major components associated with an ICF hydrodynamics simulation code. To serve as an example we draw heavily on a two-dimensional Lagrangian hydrodynamic code (ORCHID) written at the University of Rochester's Laboratory for Laser Energetics.

  20. Computer modeling and simulation in inertial confinement fusion

    SciTech Connect

    McCrory, R.L.; Verdon, C.P.

    1989-03-01

    The complex hydrodynamic and transport processes associated with the implosion of an inertial confinement fusion (ICF) pellet place considerable demands on numerical simulation programs. Processes associated with implosion can usually be described using relatively simple models, but their complex interplay requires that programs model most of the relevant physical phenomena accurately. Most hydrodynamic codes used in ICF incorporate a one-fluid, two-temperature model. Electrons and ions are assumed to flow as one fluid (no charge separation). Due to the relatively weak coupling between the ions and electrons, each species is treated separately in terms of its temperature. In this paper we describe some of the major components associated with an ICF hydrodynamics simulation code. To serve as an example we draw heavily on a two-dimensional Lagrangian hydrodynamic code (ORCHID) written at the University of Rochester's Laboratory for Laser Energetics. 46 refs., 19 figs., 1 tab.

  1. Ignition and Inertial Confinement Fusion at The National Ignition Facility

    SciTech Connect

    Moses, E

    2009-10-01

    The National Ignition Facility (NIF), the world's largest and most powerful laser system for inertial confinement fusion (ICF) and for studying high-energy-density (HED) science, is now operational at Lawrence Livermore National Laboratory (LLNL). The NIF is now conducting experiments to commission the laser drive, the hohlraum and the capsule and to develop the infrastructure needed to begin the first ignition experiments in FY 2010. Demonstration of ignition and thermonuclear burn in the laboratory is a major NIF goal. NIF will achieve this by concentrating the energy from the 192 beams into a mm{sup 3}-sized target and igniting a deuterium-tritium mix, liberating more energy than is required to initiate the fusion reaction. NIF's ignition program is a national effort managed via the National Ignition Campaign (NIC). The NIC has two major goals: execution of DT ignition experiments starting in FY2010 with the goal of demonstrating ignition and a reliable, repeatable ignition platform by the conclusion of the NIC at the end of FY2012. The NIC will also develop the infrastructure and the processes required to operate NIF as a national user facility. The achievement of ignition at NIF will demonstrate the scientific feasibility of ICF and focus worldwide attention on laser fusion as a viable energy option. A laser fusion-based energy concept that builds on NIF, known as LIFE (Laser Inertial Fusion Energy), is currently under development. LIFE is inherently safe and can provide a global carbon-free energy generation solution in the 21st century. This paper describes recent progress on NIF, NIC, and the LIFE concept.

  2. Microencapsulation and fabrication of fuel pellets for inertial confinement fusion.

    PubMed

    Nolen, R L; Kool, L B

    1981-04-01

    Various microencapsulation techniques were evaluated for fabrication of thermonuclear fuel pellets for use in existing experimental facilities studying inertial confinement fusion and in future fusion-power reactors. Coacervation, spray drying, in situ polymerization, and physical microencapsulation methods were employed. Highly spherical, hollow polymeric shells were fabricated ranging in size from 20 to 7000 micron. In situ polymerization microencapsulation with poly(methyl methacrylate) provided large shells, but problems with local wall defects still must be solved. Extension to other polymeric systems met with limited success. Requirements for inertial confinement fusion targets are described, as are the methods that were used. PMID:7229942

  3. Inertial-confinement fusion with lasers

    DOE PAGESBeta

    Betti, R.; Hurricane, O. A.

    2016-05-03

    Here, the quest for controlled fusion energy has been ongoing for over a half century. The demonstration of ignition and energy gain from thermonuclear fuels in the laboratory has been a major goal of fusion research for decades. Thermonuclear ignition is widely considered a milestone in the development of fusion energy, as well as a major scientific achievement with important applications to national security and basic sciences. The U.S. is arguably the world leader in the inertial con fment approach to fusion and has invested in large facilities to pursue it with the objective of establishing the science related tomore » the safety and reliability of the stockpile of nuclear weapons. Even though significant progress has been made in recent years, major challenges still remain in the quest for thermonuclear ignition via laser fusion.« less

  4. Inertial Confinement Fusion and the National Ignition Facility (NIF)

    SciTech Connect

    Ross, P.

    2012-08-29

    Inertial confinement fusion (ICF) seeks to provide sustainable fusion energy by compressing frozen deuterium and tritium fuel to extremely high densities. The advantages of fusion vs. fission are discussed, including total energy per reaction and energy per nucleon. The Lawson Criterion, defining the requirements for ignition, is derived and explained. Different confinement methods and their implications are discussed. The feasibility of creating a power plant using ICF is analyzed using realistic and feasible numbers. The National Ignition Facility (NIF) at Lawrence Livermore National Laboratory is shown as a significant step forward toward making a fusion power plant based on ICF. NIF is the world’s largest laser, delivering 1.8 MJ of energy, with a peak power greater than 500 TW. NIF is actively striving toward the goal of fusion energy. Other uses for NIF are discussed.

  5. Inertial Confinement Fusion R&D and Nuclear Proliferation

    SciTech Connect

    Robert J. Goldston

    2011-04-28

    In a few months, or a few years, the National Ignition Facility (NIF) at the Lawrence Livermore National Laboratory may achieve fusion gain using 192 powerful lasers to generate x-rays that will compress and heat a small target containing isotopes of hydrogen. This event would mark a major milestone after decades of research on inertial confinement fusion (ICF). It might also mark the beginning of an accelerated global effort to harness fusion energy based on this science and technology. Unlike magnetic confinement fusion (ITER, 2011), in which hot fusion fuel is confined continuously by strong magnetic fields, inertial confinement fusion involves repetitive fusion explosions, taking advantage of some aspects of the science learned from the design and testing of hydrogen bombs. The NIF was built primarily because of the information it would provide on weapons physics, helping the United States to steward its stockpile of nuclear weapons without further underground testing. The U.S. National Academies' National Research Council is now hosting a study to assess the prospects for energy from inertial confinement fusion. While this study has a classified sub-panel on target physics, it has not been charged with examining the potential nuclear proliferation risks associated with ICF R&D. We argue here that this question urgently requires direct and transparent examination, so that means to mitigate risks can be assessed, and the potential residual risks can be balanced against the potential benefits, now being assessed by the NRC. This concern is not new (Holdren, 1978), but its urgency is now higher than ever before.

  6. Inertial-Electrostatic Confinement (IEC) Fusion For Space Propulsion

    NASA Technical Reports Server (NTRS)

    Nadler, Jon

    1999-01-01

    An Inertial-Electrostatic Confinement (IEC) device was assembled at the Marshall Space Flight Center (MSFC) Propulsion Research Center (PRC) to study the possibility of using IEC technology for deep space propulsion and power. Inertial-Electrostatic Confinement is capable of containing a nuclear fusion plasma in a series of virtual potential wells. These wells would substantially increase plasma confinement, possibly leading towards a high-gain, breakthrough fusion device. A one-foot in diameter IEC vessel was borrowed from the Fusion Studies Laboratory at the University of Illinois @ Urbana-Champaign for the summer. This device was used in initial parameterization studies in order to design a larger, actively cooled device for permanent use at the PRC.

  7. Inertial-Electrostatic Confinement (IEC) Fusion for Space Propulsion

    NASA Technical Reports Server (NTRS)

    Nadler, Jon

    1999-01-01

    An Inertial-Electrostatic Confinement (IEC) device was assembled at the Marshall Space Flight Center (MSFC) Propulsion Research Center (PRC) to study the possibility of using EEC technology for deep space propulsion and power. Inertial-Electrostatic Confinement is capable of containing a nuclear fusion plasma in a series of virtual potential wells. These wells would substantially increase plasma confinement, possibly leading towards a high-gain, breakthrough fusion device. A one-foot in diameter IEC vessel was borrowed from the Fusion Studies Laboratory at the University of Illinois@Urbana-Champaign for the summer. This device was used in initial parameterization studies in order to design a larger, actively cooled device for permanent use at the PRC.

  8. Progress in toroidal confinement and fusion research

    SciTech Connect

    Furth, H.P.

    1987-10-01

    During the past 30 years, the characteristic T/sub i/n tau/sub E/-value of toroidal-confinement experiments has advanced by more than seven orders of magnitude. Part of this advance has been due to an increase of gross machine parameters. Most of this advance has been due to an increase of gross machine parameters. Most of the advance is associated with improvements in the ''quality of plasma confinement.'' The combined evidence of spherator and tokamak research clarifies the role of magnetic-field geometry in determining confinement and points to the importance of shielding out plasma edge effects. A true physical understanding of anomalous transport remains to be achieved. 39 refs., 11 figs., 1 tab.

  9. Coupling of transit time instabilities in electrostatic confinement fusion devices

    SciTech Connect

    Gruenwald, J. Fröhlich, M.

    2015-07-15

    A model of the behavior of transit time instabilities in an electrostatic confinement fusion reactor is presented in this letter. It is demonstrated that different modes are excited within the spherical cathode of a Farnsworth fusor. Each of these modes is dependent on the fusion products as well as the acceleration voltage applied between the two electrodes and they couple to a resulting oscillation showing non-linear beat phenomena. This type of instability is similar to the transit time instability of electrons between two resonant surfaces but the presence of ions and the occurring fusion reactions alter the physics of this instability considerably. The physics of this plasma instability is examined in detail for typical physical parameter ranges of electrostatic confinement fusion devices.

  10. Coupling of transit time instabilities in electrostatic confinement fusion devices

    NASA Astrophysics Data System (ADS)

    Gruenwald, J.; Fröhlich, M.

    2015-07-01

    A model of the behavior of transit time instabilities in an electrostatic confinement fusion reactor is presented in this letter. It is demonstrated that different modes are excited within the spherical cathode of a Farnsworth fusor. Each of these modes is dependent on the fusion products as well as the acceleration voltage applied between the two electrodes and they couple to a resulting oscillation showing non-linear beat phenomena. This type of instability is similar to the transit time instability of electrons between two resonant surfaces but the presence of ions and the occurring fusion reactions alter the physics of this instability considerably. The physics of this plasma instability is examined in detail for typical physical parameter ranges of electrostatic confinement fusion devices.

  11. Inertial Confinement Fusion Target Component Fabrication and Technology Development Support

    SciTech Connect

    Steinman, D.

    1993-03-01

    On December 31, 1990, the US Department of Energy entered into a contract with General Atomics (GA) to be the Inertial Confinement Fusion (ICF) Target Component Fabrication and Technology Development Support contractor. This report documents the technical activities of the period January 1, 1991 through September 30, 1992. During this period, GA was assigned 15 tasks in support of the Inertial Confinement Fusion program and its laboratories. These tasks included Facilities Activation, Staff Development, and Capabilities Validation to establish facilities and equipment, and demonstrate capability to perform ICF target fabrication research, development and production activities. The capabilities developed and demonstrated are those needed for fabrication and precise characterization of polymer shells and polymer coatings. We made progress toward production capability for glass shells, barrier layer coatings, and gas idling of shells. We fabricated over 1000 beam diagnostic foil targets for Sandia National Laboratory Albuquerque and provided full-time on-site engineering support for target fabrication and characterization. We initiated development of methods to fabricate polymer shells by a controlled mass microencapsulation technique, and performed chemical syntheses of several chlorine- and silicon-doped polymer materials for the University of Rochester's Laboratory for Laser Energetics (UR/LLE). We performed the conceptual design of a cryogenic target handling system for UR/LLE that will fill, transport, layer, and characterize targets filled with cryogenic deuterium or deuterium-tritium fuel, and insert these cryogenic targets into the OMEGA-Upgrade target chamber for laser implosion experiments. This report summarizes and documents the technical progress made on these tasks.

  12. Status of target physics for inertial confinement fusion

    NASA Astrophysics Data System (ADS)

    1990-03-01

    A four day review to assess the status of target physics of inertial confinement fusion was held at U.S. Department of Energy (DOE) Headquarters on November 14 to 17, 1988. This review completes the current series of reviews of the inertial fusion program elements to assess the status of the data base for a decision to proceed with the proposed Laboratory Microfusion Facility (LMF) that is being planned. In addition to target physics, the program elements that have been reviewed previously include the driver technology development for KrF and solid-state lasers, and the light-on beam pulsed power system. This series of reviews was undertaken for internal DOE assessment in anticipation of the ICF program review mandated by the Congress in 1988 to be completed in 1990 to assess the significance and implications of the progress that has been realized in the laboratory and the underground Halite/Centurion experiments. For this target physics review, both the direct and the indirect drive approaches were considered. The principal issues addressed in this review were: (1) the adequacy of the present target physics data base in making a decision to proceed with design and construction of LMF now as opposed to continuing planning activities at this time; (2) the desirability of specific additional target physics data in reducing the risk involved in a DOE decision to construct an LMF; (3) the continuing role of Halite/Centurion experiments; (4) the priority given to the direct drive approach; and (5) the optimal program-elements structure to resolve the critical issues of an LMF decision. Specific findings relating to these five issues are summarized.

  13. An antiproton catalyst for inertial confinement fusion propulsion

    NASA Technical Reports Server (NTRS)

    Lewis, Raymond A.; Newton, Richard; Smith, Gerald A.; Toothacker, William S.; Kanzleiter, Randall J.

    1990-01-01

    This paper discusses the concept of an inertial confinement fusion propulsion system involving an antiproton catalyst (for antiproton-induced fission). It is argued that, when the two processes, fusion and antimatter annihilation, are combined into one system, a viable candidate propulsion system for planetary exploration emerges. It is shown that as much as 7.6 GW of power, well within the requrements for interplanetary travel, can be achieved using existing driver technologies and available quantities of antiprotons.

  14. Heavy ion drivers for inertial confinement fusion

    SciTech Connect

    Keefe, D.

    1983-12-01

    The advantages of heavy ion beams as a way of delivering the needed energy and power to an inertial fusion target are surveyed. The existing broad technology base of particle accelerators provides an important foundation for designing, costing, and evaluating proposed systems. The sequence of steps needed for the verification of the heavy ion approach is described; recent research results are even more encouraging than had been assumed hitherto.

  15. Inertial confinement fusion quarterly report, July--September 1994. Volume 4, Number 4

    SciTech Connect

    Honea, E.

    1994-09-01

    The ICF Quarterly continues with six articles in this issue describing recent developments in the Inertial Confinement Fusion (ICF) Program at Lawrence Livermore National Laboratory. The topics include plasma characterization, production of millimeter scale-length plasmas for studying laser-plasma instabilities, hohlraum physics, three-dimensional hydrodynamic modeling, crystal growth, and laser-beam smoothing.

  16. Experimental Test of the Polarization Persistence in Inertial Confinement Fusion

    NASA Astrophysics Data System (ADS)

    Didelez, J. P.; Deutsch, C.; Fujiwara, M.; Nakai, M.; Utsuro, M.

    2016-03-01

    The complete deuteron and triton polarization in the DT fusion increases the reactivity by 50%. For Inertial Confinement Fusion (ICF), due to the dynamics of the fusion reaction process, the fusion rate could even be further increased. It has been argued that the polarization would survive as well in magnetic as in inertial confinements. Recently, we have proposed an experiment to test the persistence of the polarization in a fusion process, using a powerful laser hitting a polarized HD target.The polarized deuterons heated in the plasma induced by the laser can fuse. The corresponding reaction is: D + D → 3He + n. The angular distribution of the emitted neutrons and the change in the corresponding total cross section are signatures to estimate the polarization persistency. A proposal to test the persistence of the polarization in ICF has been accepted at ILE: the POLAF project (POlarization in LAser Fusion Process). It uses the polarized HD targets produced at RCNP and the powerful ILE lasers, as well as the neutron detectors existing there. Both institutions are on the same campus at Osaka University. The description of the POLAF experiment and of the corresponding set-up is given.

  17. General principles of magnetic fusion confinement

    SciTech Connect

    Hogan, J.T.

    1980-01-01

    A few of the areas are described in which there is close interaction between atomic/molecular (A and M) and magnetic fusion physics. The comparisons between predictions of neoclassical transport theory and experiment depend on knowledge of ionization and recombination rate coefficients. Modeling of divertor/scrapeoff plasmas requires better low energy charge exchange cross sections for H + A/sup n+/ collisions. The range of validity of neutral beam trapping cross sections must be broadened, both to encompass the energies typical of present injection experiments and to deal with the problem of prompt trapping of highly excited beam atoms at high energy. Plasma fueling models present certain anomalies that could be resolved by calculation and measurement of low energy (<1 keV) charge exchange cross sections.

  18. Review of the Inertial Fusion Energy Program

    SciTech Connect

    none,

    2004-03-29

    Igniting fusion fuel in the laboratory remains an alluring goal for two reasons: the desire to study matter under the extreme conditions needed for fusion burn, and the potential of harnessing the energy released as an attractive energy source for mankind. The inertial confinement approach to fusion involves rapidly compressing a tiny spherical capsule of fuel, initially a few millimeters in radius, to densities and temperatures higher than those in the core of the sun. The ignited plasma is confined solely by its own inertia long enough for a significant fraction of the fuel to burn before the plasma expands, cools down and the fusion reactions are quenched. The potential of this confinement approach as an attractive energy source is being studied in the Inertial Fusion Energy (IFE) program, which is the subject of this report. A complex set of interrelated requirements for IFE has motivated the study of novel potential solutions. Three types of “drivers” for fuel compression are presently studied: high-averagepower lasers (HAPL), heavy-ion (HI) accelerators, and Z-Pinches. The three main approaches to IFE are based on these drivers, along with the specific type of target (which contains the fuel capsule) and chamber that appear most promising for a particular driver.

  19. Heat of fusion of primary alcohol confined in Nano pores

    NASA Astrophysics Data System (ADS)

    Griffin, Harrisonn; Amanue, Samuel

    Melting behavior of physically confined 1-decanol in nano porous silica was probed using a Differential Scanning Calorimeter (DSC). In agreement with the Gibbs-Thompson prediction, we observe that the melting temperature of the confined 1-decanol scales inversely with the physical size of the pores. Contrary to the assumption used in developing the Gibbs-Thompson equation, however, the apparent heat of fusion decreases as the the pore size decreases. Previously, several models have been proposed where the interfacial layer/s of molecules do not participate in the phase transition and thereby would not contribute to the heat of fusion. While these could reconcile the seeming contradiction, annealing the nano confined materials enables some of the interfacial layers to be incorporated into an existing crystal. This leads to an increase in the apparent heat of fusion and a systematic relationship exists between the annealing temperature and the increase in the apparent heat of fusion. This work was partially supported by NSF-DMR: 1229142.

  20. Alpha Heating and Burning Plasmas in Inertial Confinement Fusion

    NASA Astrophysics Data System (ADS)

    Betti, R.; Christopherson, A. R.; Bose, A.; Woo, K. M.

    2016-05-01

    Assessing the degree to which fusion alpha particles contribute to the fusion yield is essential to understanding the onset of the thermal runaway process of thermonuclear ignition. It is shown that in inertial confinement fusion, the yield enhancement due to alpha particle heating (before ignition occurs) depends on the generalized Lawson parameter that can be inferred from experimental observables. A universal curve valid for arbitrary laser-fusion targets shows the yield amplification due to alpha heating for a given value of the Lawson parameter. The same theory is used to determine the onset of the burning plasma regime when the alpha heating exceeds the compression work. This result can be used to assess the performance of current ignition experiments at the National Ignition Facility.

  1. Inertially confined fusion using heavy ion drivers

    SciTech Connect

    Herrmannsfeldt, W.B.; Bangerter, R.O.; Bock, R.; Hogan, W.J.; Lindl, J.D.

    1991-10-01

    The various technical issues of HIF will be briefly reviewed in this paper. It will be seen that there are numerous areas in common in all the approaches to HIF. In the recent International Symposium on Heavy Ion Inertial Fusion, the attendees met in specialized workshop sessions to consider the needs for research in each area. Each of the workshop groups considered the key questions of this report: (1) Is this an appropriate time for international collaboration in HIF? (2) Which problems are most appropriate for such collaboration? (3) Can the sharing of target design information be set aside until other driver and systems issues are better resolved, by which time it might be supposed that there could be a relaxation of classification of target issues? (4) What form(s) of collaboration are most appropriate, e.g., bilateral or multilateral? (5) Can international collaboration be sensibly attempted without significant increases in funding for HIF? The authors of this report share the conviction that collaboration on a broad scale is mandatory for HIF to have the resources, both financial and personnel, to progress to a demonstration experiment. Ultimately it may be possible for a single driver with the energy, power, focusibility, and pulse shape to satisfy the needs of the international community for target physics research. Such a facility could service multiple experimental chambers with a variety of beam geometries and target concepts.

  2. Inertially confined fusion using heavy ion drivers

    SciTech Connect

    Herrmannsfeldt, W.B. ); Bangerter, R.O. ); Bock, R. ); Hogan, W.J.; Lindl, J.D. )

    1991-10-01

    The various technical issues of HIF will be briefly reviewed in this paper. It will be seen that there are numerous areas in common in all the approaches to HIF. In the recent International Symposium on Heavy Ion Inertial Fusion, the attendees met in specialized workshop sessions to consider the needs for research in each area. Each of the workshop groups considered the key questions of this report: (1) Is this an appropriate time for international collaboration in HIF (2) Which problems are most appropriate for such collaboration (3) Can the sharing of target design information be set aside until other driver and systems issues are better resolved, by which time it might be supposed that there could be a relaxation of classification of target issues (4) What form(s) of collaboration are most appropriate, e.g., bilateral or multilateral (5) Can international collaboration be sensibly attempted without significant increases in funding for HIF The authors of this report share the conviction that collaboration on a broad scale is mandatory for HIF to have the resources, both financial and personnel, to progress to a demonstration experiment. Ultimately it may be possible for a single driver with the energy, power, focusibility, and pulse shape to satisfy the needs of the international community for target physics research. Such a facility could service multiple experimental chambers with a variety of beam geometries and target concepts.

  3. Simulation of transition dynamics to high confinement in fusion plasmas

    NASA Astrophysics Data System (ADS)

    Nielsen, A. H.; Xu, G. S.; Madsen, J.; Naulin, V.; Juul Rasmussen, J.; Wan, B. N.

    2015-12-01

    The transition dynamics from the low (L) to the high (H) confinement mode in magnetically confined plasmas is investigated using a first-principles four-field fluid model. Numerical results are in agreement with measurements from the Experimental Advanced Superconducting Tokamak - EAST. Particularly, the slow transition with an intermediate dithering phase is well reproduced at proper parameters. The model recovers the power threshold for the L-H transition as well as the decrease in power threshold switching from single to double null configuration observed experimentally. The results are highly relevant for developing predictive models of the transition, essential for understanding and optimizing future fusion power reactors.

  4. HYLIFE-2 inertial confinement fusion reactor design

    SciTech Connect

    Moir, R.W.

    1990-10-04

    The HYLIFE-II inertial fusion power plant design study uses a liquid fall, in the form of jets to protect the first structural wall from neutron damage, x-rays, and blast to provide a 30-y lifetime. HYLIFE-I used liquid lithium. HYLIFE-II avoids the fire hazard of lithium by using a molten salt composed of fluorine, lithium, and beryllium (Li{sub 2}BeF{sub 4}) called Flibe. Access for heavy-ion beams is provided. Calculations for assumed heavy-ion beam performance show a nominal gain of 70 at 5 MJ producing 350 MJ, about 5.2 times less yield than the 1.8 GJ from a driver energy of 4.5 MJ with gain of 400 for HYLIFE-I. The nominal 1 GWe of power can be maintained by increasing the repetition rate by a factor of about 5.2, from 1.5 to 8 Hz. A higher repetition rate requires faster re-establishment of the jets after a shot, which can be accomplished in part by decreasing the jet fall height and increasing the jet flow velocity. Multiple chambers may be required. In addition, although not considered for HYLIFE-I, there is undoubtedly liquid splash that must be forcibly cleared because gravity is too slow, especially at high repetition rates. Splash removal can be accomplished by either pulsed or oscillating jet flows. The cost of electricity is estimated to be 0.09$/kW{center dot}h in constant 1988 dollars, about twice that of future coal and light water reactor nuclear power. The driver beam cost is about one-half the total cost. 12 refs., 9 figs., 5 tabs.

  5. Inertial Confinement Fusion Annual Report 1999

    SciTech Connect

    Kauffman, R

    2001-07-01

    The ICF Program has undergone a significant change in 1999 with the decommissioning of the Nova laser and the transfer of much of the experimental program to the OMEGA laser at the University of Rochester. The Nova laser ended operations with the final experiment conducted on May 27, 1999. This marked the end to one of DOE's most successful experimental facilities. Since its commissioning in 1985, Nova performed 13,424 experiments supporting ICF, Defense Sciences, high-power laser research, and basic science research. At the time of its commissioning, Nova was the world's most powerful laser. Its early experiments demonstrated that 3{omega} light could produce high-drive, low-preheat environment required for indirect-drive ICE. In the early 1990s, the technical program on Nova for indirect drive ignition was defined by the Nova technical contract established by National Academy Review of ICF in 1990. Successful completion of this research program contributed significantly to the recommendation by the ICF Advisory Committee in 1995 to proceed with the construction of the National Ignition Facility? Nova experiments also demonstrated the utility of high-powered lasers for studying the physics of interest to Defense Sciences. Now, high-powered lasers along with pulsed-power machines are the principal facilities for studying high energy density science in DOE's Stockpile Stewardship Program (SSP). In 1997, one beam of Nova was converted to a short pulsed beam producing a petawatt of power in subpicosecond pulses. The petawatt beam was used for pioneering research in short-pulse laser-matter interactions relevant to fast ignitor ICF and short pulsed x-ray, electron, and particle production for use as probes. Nova is being disassembled and the space is being used to support NIF construction. Nova components are being distributed to a number of other laser laboratories around the world for reuse as determined by DOE. This report summarizes the research performed by the

  6. Measurements of temperature and density in magnetic confinement fusion devices

    NASA Astrophysics Data System (ADS)

    Udintsev, Victor S.

    2010-11-01

    Controlled thermonuclear fusion can fulfil the demand of mankind to have an inexhaustible source of energy that does not cause any serious environmental pollution. The aim of fusion research is to build a continuously operating reactor in which the energy released by the fusion reactions is sufficiently high to keep the plasma hot and to produce more fusion reactions. The knowledge of the plasma temperature and density, together with the energy confinement time, is therefore very important for the effective control of the self-sustained fusion reactor. Various methods and diagnostics for measurements of the plasma temperature and density in present experimental fusion devices, as well as requirements for the future fusion reactors, will be discussed. A special attention will be given to the temperature and density diagnostics in ITER tokamak, which is presently under construction by several international partners at Cadarache in France. Development of these diagnostics is a major challenge because of severe environment, strict engineering requirements, safety issues and the need for high reliability in the measurements.

  7. Nuclear-data needs for inertial-confinement fusion (ICF)

    SciTech Connect

    Haight, R.C.; Motz, H.T.

    1983-05-09

    Our survey was limited to ICF programs in the United States. It included researchers in laser and heavy ion fusion, target design, target diagnostics, and conceptual reactor design. We asked each of these people to read the current data needs for magnetic fusion energy and to comment on additional data that they require.

  8. Tgermonuclear Ignition in Inertial Confinement Fusion and Comparison with Magnetic Confinement

    SciTech Connect

    Betti, R.; Chang, P.Y.; Spears, B.K.; Anderson, K.S.; Edwards, J.; Fatenejad, M.; Lindl, J.D.; McCrory, R.L.; Nora, R.; Shvarts, D.

    2010-04-23

    The physics of thermonuclear ignition in inertial confinement fusion (ICF) is presented in the familiar frame of a Lawson-type criterion. The product of the plasma pressure and confinement time Ptau for ICF is cast in terms of measurable parameters and its value is estimated for cryogenic implosions. An overall ignition parameter chi including pressure, confinement time, and temperature is derived to complement the product Ptau. A metric for performance assessment should include both chi and Ptau. The ignition parameter and the product Ptau are compared between inertial and magnetic-confinement fusion. It is found that cryogenic implosions on OMEGA [T. R. Boehly et al., Opt. Commun. 133, 495 (1997)] have achieved Ptau ~ 1.5 atm s comparable to large tokamaks such as the Joint European Torus [P. H. Rebut and B. E. Keen, Fusion Technol. 11, 13 (1987)] where Ptau ~ 1 atm s. Since OMEGA implosions are relatively cold (T ~ 2 keV), their overall ignition parameter chi ~ 0.02–0.03 is ~5X lower than in JET (chi ~ 0.13), where the average temperature is about 10 keV.

  9. Thermonuclear ignition in inertial confinement fusion and comparison with magnetic confinement

    SciTech Connect

    Betti, R.; Chang, P. Y.; Anderson, K. S.; Nora, R.; Spears, B. K.; Edwards, J.; Lindl, J. D.; Fatenejad, M.; McCrory, R. L.; Shvarts, D.

    2010-05-15

    The physics of thermonuclear ignition in inertial confinement fusion (ICF) is presented in the familiar frame of a Lawson-type criterion. The product of the plasma pressure and confinement time Ptau for ICF is cast in terms of measurable parameters and its value is estimated for cryogenic implosions. An overall ignition parameter chi including pressure, confinement time, and temperature is derived to complement the product Ptau. A metric for performance assessment should include both chi and Ptau. The ignition parameter and the product Ptau are compared between inertial and magnetic-confinement fusion. It is found that cryogenic implosions on OMEGA[T. R. Boehly et al., Opt. Commun. 133, 495 (1997)] have achieved Ptauapprox1.5 atm s comparable to large tokamaks such as the Joint European Torus [P. H. Rebut and B. E. Keen, Fusion Technol. 11, 13 (1987)] where Ptauapprox1 atm s. Since OMEGA implosions are relatively cold (Tapprox2 keV), their overall ignition parameter chiapprox0.02-0.03 is approx5x lower than in JET (chiapprox0.13), where the average temperature is about 10 keV.

  10. Laser targets compensate for limitations in inertial confinement fusion drivers

    NASA Astrophysics Data System (ADS)

    Kilkenny, J. D.; Alexander, N. B.; Nikroo, A.; Steinman, D. A.; Nobile, A.; Bernat, T.; Cook, R.; Letts, S.; Takagi, M.; Harding, D.

    2005-10-01

    Success in inertial confinement fusion (ICF) requires sophisticated, characterized targets. The increasing fidelity of three-dimensional (3D), radiation hydrodynamic computer codes has made it possible to design targets for ICF which can compensate for limitations in the existing single shot laser and Z pinch ICF drivers. Developments in ICF target fabrication technology allow more esoteric target designs to be fabricated. At present, requirements require new deterministic nano-material fabrication on micro scale.

  11. Inertial confinement fusion method producing line source radiation fluence

    DOEpatents

    Rose, Ronald P.

    1984-01-01

    An inertial confinement fusion method in which target pellets are imploded in sequence by laser light beams or other energy beams at an implosion site which is variable between pellet implosions along a line. The effect of the variability in position of the implosion site along a line is to distribute the radiation fluence in surrounding reactor components as a line source of radiation would do, thereby permitting the utilization of cylindrical geometry in the design of the reactor and internal components.

  12. Radiation and confinement in 0D fusion systems codes

    NASA Astrophysics Data System (ADS)

    Lux, H.; Kemp, R.; Fable, E.; Wenninger, R.

    2016-07-01

    In systems modelling for fusion power plants, it is essential to robustly predict the performance of a given machine design (including its respective operating scenario). One measure of machine performance is the energy confinement time {τ\\text{E}} that is typically predicted from experimentally derived confinement scaling laws (e.g. IPB98(y,2)). However, the conventionally used scaling laws have been derived for ITER which—unlike a fusion power plant—will not have significant radiation inside the separatrix. In the absence of a new high core radiation relevant confinement scaling, we propose an ad hoc correction to the loss power {{P}\\text{L}} used in the ITER confinement scaling and the calculation of the stored energy {{W}\\text{th}} by the radiation losses from the ‘core’ of the plasma {{P}\\text{rad,\\text{core}}} . Using detailed ASTRA / TGLF simulations, we find that an appropriate definition of {{P}\\text{rad,\\text{core}}} is given by 60% of all radiative losses inside a normalised minor radius {ρ\\text{core}}=0.75 . We consider this an improvement for current design predictions, but it is far from an ideal solution. We therefore encourage more detailed experimental and theoretical work on this issue.

  13. Fuel gain exceeding unity in an inertially confined fusion implosion.

    PubMed

    Hurricane, O A; Callahan, D A; Casey, D T; Celliers, P M; Cerjan, C; Dewald, E L; Dittrich, T R; Döppner, T; Hinkel, D E; Berzak Hopkins, L F; Kline, J L; Le Pape, S; Ma, T; MacPhee, A G; Milovich, J L; Pak, A; Park, H-S; Patel, P K; Remington, B A; Salmonson, J D; Springer, P T; Tommasini, R

    2014-02-20

    Ignition is needed to make fusion energy a viable alternative energy source, but has yet to be achieved. A key step on the way to ignition is to have the energy generated through fusion reactions in an inertially confined fusion plasma exceed the amount of energy deposited into the deuterium-tritium fusion fuel and hotspot during the implosion process, resulting in a fuel gain greater than unity. Here we report the achievement of fusion fuel gains exceeding unity on the US National Ignition Facility using a 'high-foot' implosion method, which is a manipulation of the laser pulse shape in a way that reduces instability in the implosion. These experiments show an order-of-magnitude improvement in yield performance over past deuterium-tritium implosion experiments. We also see a significant contribution to the yield from α-particle self-heating and evidence for the 'bootstrapping' required to accelerate the deuterium-tritium fusion burn to eventually 'run away' and ignite. PMID:24522535

  14. Measuring time of flight of fusion products in an inertial electrostatic confinement fusion device for spatial profiling of fusion reactions

    NASA Astrophysics Data System (ADS)

    Donovan, D. C.; Boris, D. R.; Kulcinski, G. L.; Santarius, J. F.; Piefer, G. R.

    2013-03-01

    A new diagnostic has been developed that uses the time of flight (TOF) of the products from a nuclear fusion reaction to determine the location where the fusion reaction occurred. The TOF diagnostic uses charged particle detectors on opposing sides of the inertial electrostatic confinement (IEC) device that are coupled to high resolution timing electronics to measure the spatial profile of fusion reactions occurring between the two charged particle detectors. This diagnostic was constructed and tested by the University of Wisconsin-Madison Inertial Electrostatic Confinement Fusion Group in the IEC device, HOMER, which accelerates deuterium ions to fusion relevant energies in a high voltage (˜100 kV), spherically symmetric, electrostatic potential well [J. F. Santarius, G. L. Kulcinski, R. P. Ashley, D. R. Boris, B. B. Cipiti, S. K. Murali, G. R. Piefer, R. F. Radel, T. E. Radel, and A. L. Wehmeyer, Fusion Sci. Technol. 47, 1238 (2005)]. The TOF diagnostic detects the products of D(d,p)T reactions and determines where along a chord through the device the fusion event occurred. The diagnostic is also capable of using charged particle spectroscopy to determine the Doppler shift imparted to the fusion products by the center of mass energy of the fusion reactants. The TOF diagnostic is thus able to collect spatial profiles of the fusion reaction density along a chord through the device, coupled with the center of mass energy of the reactions occurring at each location. This provides levels of diagnostic detail never before achieved on an IEC device.

  15. Measuring time of flight of fusion products in an inertial electrostatic confinement fusion device for spatial profiling of fusion reactions

    SciTech Connect

    Donovan, D. C.; Boris, D. R.; Kulcinski, G. L.; Santarius, J. F.; Piefer, G. R.

    2013-03-15

    A new diagnostic has been developed that uses the time of flight (TOF) of the products from a nuclear fusion reaction to determine the location where the fusion reaction occurred. The TOF diagnostic uses charged particle detectors on opposing sides of the inertial electrostatic confinement (IEC) device that are coupled to high resolution timing electronics to measure the spatial profile of fusion reactions occurring between the two charged particle detectors. This diagnostic was constructed and tested by the University of Wisconsin-Madison Inertial Electrostatic Confinement Fusion Group in the IEC device, HOMER, which accelerates deuterium ions to fusion relevant energies in a high voltage ({approx}100 kV), spherically symmetric, electrostatic potential well [J. F. Santarius, G. L. Kulcinski, R. P. Ashley, D. R. Boris, B. B. Cipiti, S. K. Murali, G. R. Piefer, R. F. Radel, T. E. Radel, and A. L. Wehmeyer, Fusion Sci. Technol. 47, 1238 (2005)]. The TOF diagnostic detects the products of D(d,p)T reactions and determines where along a chord through the device the fusion event occurred. The diagnostic is also capable of using charged particle spectroscopy to determine the Doppler shift imparted to the fusion products by the center of mass energy of the fusion reactants. The TOF diagnostic is thus able to collect spatial profiles of the fusion reaction density along a chord through the device, coupled with the center of mass energy of the reactions occurring at each location. This provides levels of diagnostic detail never before achieved on an IEC device.

  16. Progress and Future Directions in Confined Magnetic Fusion Simulation

    NASA Astrophysics Data System (ADS)

    Chan, V. S.

    2004-05-01

    The complexity of fusion plasmas makes the goal of integrated predictive simulation for optimization of fusion systems extremely challenging. Sophisticated computational models are under development for individual features of magnetically confined plasmas, enabled by increased scientific understanding and improvements in computer technology. Simulation codes, particle- and continuum-based, are being developed to elucidate the ability of fusion devices to contain mass, heat and momentum. Rigorous benchmarking among different codes has resulted in increased confidence in the predictive capability. Advances made in extended MHD simulations of actual experiments have led to deeper understanding of the nonlinear evolution of MHD instabilities that set the pressure limit of fusion devices. Simulation of the plasma edge, which controls the overall fusion performance, is especially difficult due to the wide range of spatial and temporal scales involved, as well as the need for a physics model that accurately describes collisionless and collisional plasma. We highlight encouraging progress in plasma microturbulence and extended MHD and a new challenge in simulation of the plasma edge.

  17. Characterization of inertial confinement fusion (ICF) targets using PIXE, RBS, and STIM analysis.

    PubMed

    Li, Yongqiang; Liu, Xue; Li, Xinyi; Liu, Yiyang; Zheng, Yi; Wang, Min; Shen, Hao

    2013-08-01

    Quality control of the inertial confinement fusion (ICF) target in the laser fusion program is vital to ensure that energy deposition from the lasers results in uniform compression and minimization of Rayleigh-Taylor instabilities. The technique of nuclear microscopy with ion beam analysis is a powerful method to provide characterization of ICF targets. Distribution of elements, depth profile, and density image of ICF targets can be identified by particle-induced X-ray emission, Rutherford backscattering spectrometry, and scanning transmission ion microscopy. We present examples of ICF target characterization by nuclear microscopy at Fudan University in order to demonstrate their potential impact in assessing target fabrication processes. PMID:23702102

  18. Recent diagnostic development for inertial confinement fusion research at Los Alamos National Laboratory

    SciTech Connect

    Murphy, T.J.; Oertel, J.A.; Archuleta, T.N.

    1997-09-01

    Inertial Confinement Fusion (ICF) experiments require sophisticated diagnostics with temporal resolution measured in tens of picoseconds and spatial resolutions measured in microns. The Los Alamos ICF Program is currently supporting a number of diagnostics on the Nova and Triden laser facilities, and is developing new diagnostics for use on the Omega laser facility. New systems and technologies are being developed for use on the National Ignition Facility, which is expected to be operational early in the next decade.

  19. Inertial Confinement Fusion quarterly report, October--December 1994. Volume 5, No. 1

    SciTech Connect

    1995-09-01

    The ICF quarterly report is published by the Inertial Confinement Fusion Program at the Lawrence Livermore National Laboratory. Topics included in this issue include: system description and initial performance results for beamlet, design and performance of the beamlet amplifiers and optical switch, beamlet pulse-generation and wavefront-control system, large-aperture, high- damage-threshold optics for beamlet, beamlet pulsed power system, beamlet laser diagnostics, and beam propagation and frequency conversion modeling for the beamlet laser.

  20. Programmed environment management of confined microsocieties

    NASA Technical Reports Server (NTRS)

    Emurian, Henry H.

    1988-01-01

    A programmed environment is described that assists the implementation and management of schedules governing access to all resources and information potentially available to members of a confined microsociety. Living and work schedules are presented that were designed to build individual and group performance repertoires in support of study objectives and sustained adaptation by participants. A variety of measurement requirements can be programmed and standardized to assure continuous assessment of the status and health of a confined microsociety.

  1. KrF lasers for inertial confinement fusion

    SciTech Connect

    Harris, D.B.; Cartwright, D.C.; Figueira, J.F.; McDonald, T.E.; Sorem, M.E.

    1989-01-01

    The KrF laser has been proposed for inertial confinement fusion (ICF) since its discovery in 1975. Since that time, the laser has seen significant development and has been increased in energy many orders of magnitude to the several kilojoule energy level. The suitability of the KrF laser as a driver for ICF energy applications has been continually reviewed. The latest assessments indicate that the KrF laser still appears to be the leading laser candidate. A worldwide effort exists to advance the KrF laser for ICF applications. 21 refs., 1 fig.

  2. Multibeam seeded brillouin sidescatter in inertial confinement fusion experiments.

    PubMed

    Turnbull, D; Michel, P; Ralph, J E; Divol, L; Ross, J S; Berzak Hopkins, L F; Kritcher, A L; Hinkel, D E; Moody, J D

    2015-03-27

    We present the first observations of multibeam weakly seeded Brillouin sidescatter in indirect-drive inertial confinement fusion (ICF) experiments. Two seeding mechanisms have been identified and quantified: specular reflections ("glint") from opposite hemisphere beams, and Brillouin backscatter from neighboring beams with a different angle of incidence. Seeded sidescatter can dominate the overall coupling losses, so understanding this process is crucial for proper accounting of energy deposition and drive symmetry. Glint-seeded scattered light could also be used to probe hydrodynamic conditions inside ICF targets. PMID:25860748

  3. Multibeam Stimulated Raman Scattering in Inertial Confinement Fusion Conditions.

    PubMed

    Michel, P; Divol, L; Dewald, E L; Milovich, J L; Hohenberger, M; Jones, O S; Hopkins, L Berzak; Berger, R L; Kruer, W L; Moody, J D

    2015-07-31

    Stimulated Raman scattering from multiple laser beams arranged in a cone sharing a common daughter wave is investigated for inertial confinement fusion (ICF) conditions in a inhomogeneous plasma. It is found that the shared electron plasma wave (EPW) process, where the lasers collectively drive the same EPW, can lead to an absolute instability when the electron density reaches a matching condition dependent on the cone angle of the laser beams. This mechanism could explain recent experimental observations of hot electrons at early times in ICF experiments, at densities well below quarter critical when two plasmon decay is not expected to occur. PMID:26274426

  4. Open-ended magnetic confinement systems for fusion

    SciTech Connect

    Post, R.F.; Ryutov, D.D.

    1995-05-01

    Magnetic confinement systems that use externally generated magnetic fields can be divided topologically into two classes: ``closed`` and `open``. The tokamak, the stellarator, and the reversed-field-pinch approaches are representatives of the first category, while mirror-based systems and their variants are of the second category. While the recent thrust of magnetic fusion research, with its emphasis on the tokamak, has been concentrated on closed geometry, there are significant reasons for the continued pursuit of research into open-ended systems. The paper discusses these reasons, reviews the history and the present status of open-ended systems, and suggests some future directions for the research.

  5. High-performance inertial confinement fusion target implosions on OMEGA

    SciTech Connect

    Meyerhofer, D. D.; McCrory, R L; Betti, R; Boehly, T R; Casey, D T; Collins, T.J.B.; Craxton, R S; Delettrez, J A; Edgell, D H; Epstein, R; Fletcher, K A; Frenje, J A; Glebov, Y Yu; Goncharov, V N; Harding, D R; Hu, S X; Igumenshchev, I V; Knauer, J P; Li, C K; Marozas, J A; Marshall, F J; McKenty, P W; Nilson, P M; Padalino, S P; Petrasso, R D; Radha, P B; Regan, S P; Sangster, T C; Seguin, F H; Seka, W; Short, R W; Shvarts, D; Skupsky, S; Soures, J M; Stoeckl, C; Theobald, W; Yaakobi, B

    2011-04-18

    The Omega Laser Facility is used to study inertial confinement fusion (ICF) concepts. This paper describes progress in direct-drive central hot-spot (CHS) ICF, shock ignition (SI) and fast ignition (FI) since the 2008 IAEA FEC conference. CHS cryogenic deuterium-tritium (DT) target implosions on OMEGA have produced the highest DT areal densities yet measured in ICF implosions (~300 mg cm{sup -2}). Integrated FI experiments have shown a significant increase in neutron yield caused by an appropriately timed high-intensity, high-energy laser pulse.

  6. Multibeam Stimulated Raman Scattering in Inertial Confinement Fusion Conditions

    NASA Astrophysics Data System (ADS)

    Michel, P.; Divol, L.; Dewald, E. L.; Milovich, J. L.; Hohenberger, M.; Jones, O. S.; Hopkins, L. Berzak; Berger, R. L.; Kruer, W. L.; Moody, J. D.

    2015-07-01

    Stimulated Raman scattering from multiple laser beams arranged in a cone sharing a common daughter wave is investigated for inertial confinement fusion (ICF) conditions in a inhomogeneous plasma. It is found that the shared electron plasma wave (EPW) process, where the lasers collectively drive the same EPW, can lead to an absolute instability when the electron density reaches a matching condition dependent on the cone angle of the laser beams. This mechanism could explain recent experimental observations of hot electrons at early times in ICF experiments, at densities well below quarter critical when two plasmon decay is not expected to occur.

  7. Fusion programs in Applied Plasma Physics

    SciTech Connect

    Not Available

    1992-07-01

    The Applied Plasma Physics (APP) program at General Atomics (GA) described here includes four major elements: (a) Applied Plasma Physics Theory Program, (b) Alpha Particle Diagnostic, (c) Edge and Current Density Diagnostic, and (d) Fusion User Service Center (USC). The objective of the APP theoretical plasma physics research at GA is to support the DIII-D and other tokamak experiments and to significantly advance our ability to design a commercially-attractive fusion reactor. We categorize our efforts in three areas: magnetohydrodynamic (MHD) equilibria and stability; plasma transport with emphasis on H-mode, divertor, and boundary physics; and radio frequency (rf). The objective of the APP alpha particle diagnostic is to develop diagnostics of fast confined alpha particles using the interactions with the ablation cloud surrounding injected pellets and to develop diagnostic systems for reacting and ignited plasmas. The objective of the APP edge and current density diagnostic is to first develop a lithium beam diagnostic system for edge fluctuation studies on the Texas Experimental Tokamak (TEXT). The objective of the Fusion USC is to continue to provide maintenance and programming support to computer users in the GA fusion community. The detailed progress of each separate program covered in this report period is described in the following sections.

  8. The VISTA spacecraft: Advantages of ICF (Inertial Confinement Fusion) for interplanetary fusion propulsion applications

    SciTech Connect

    Orth, C.D.; Klein, G.; Sercel, J.; Hoffman, N.; Murray, K.; Chang-Diaz, F.

    1987-10-02

    Inertial Confinement Fusion (ICF) is an attractive engine power source for interplanetary manned spacecraft, especially for near-term missions requiring minimum flight duration, because ICF has inherent high power-to-mass ratios and high specific impulses. We have developed a new vehicle concept called VISTA that uses ICF and is capable of round-trip manned missions to Mars in 100 days using A.D. 2020 technology. We describe VISTA's engine operation, discuss associated plasma issues, and describe the advantages of DT fuel for near-term applications. Although ICF is potentially superior to non-fusion technologies for near-term interplanetary transport, the performance capabilities of VISTA cannot be meaningfully compared with those of magnetic-fusion systems because of the lack of a comparable study of the magnetic-fusion systems. We urge that such a study be conducted.

  9. The VISTA spacecraft: Advantages of ICF (Inertial Confinement Fusion) for interplanetary fusions propulsion applications

    NASA Technical Reports Server (NTRS)

    Orth, Charles D.; Klein, Gail; Sercel, Joel; Hoffman, Nate; Murray, Kathy; Chang-Diaz, Franklin

    1987-01-01

    Inertial Confinement Fusion (ICF) is an attractive engine power source for interplanetary manned spacecraft, especially for near-term missions requiring minimum flight duration, because ICF has inherent high power-to-mass ratios and high specific impulses. We have developed a new vehicle concept called VISTA that uses ICF and is capable of round-trip manned missions to Mars in 100 days using A.D. 2020 technology. We describe VISTA's engine operation, discuss associated plasma issues, and describe the advantages of DT fuel for near-term applications. Although ICF is potentially superior to non-fusion technologies for near-term interplanetary transport, the performance capabilities of VISTA cannot be meaningfully compared with those of magnetic-fusion systems because of the lack of a comparable study of the magnetic-fusion systems. We urge that such a study be conducted.

  10. Laser-plasma interactions relevant to Inertial Confinement Fusion

    SciTech Connect

    Wharton, K.B.

    1998-11-02

    Research into laser-driven inertial confinement fusion is now entering a critical juncture with the construction of the National Ignition Facility (NIF) at Lawrence Livermore National Laboratory (LLNL). Many of the remaining unanswered questions concerning NIF involve interactions between lasers and plasmas. With the eventual goal of fusion power in mind, laser-plasma interactions relevant to laser fusion schemes is an important topic in need of further research. This work experimentally addresses some potential shortcuts and pitfalls on the road to laser-driven fusion power. Current plans on NIF have 192 laser beams directed into a small cylindrical cavity which will contain the fusion fuel; to accomplish this the beams must cross in the entrance holes, and this intersection will be in the presence of outward-flowing plasma. To investigate the physics involved, interactions of crossing laser beams in flowing plasmas are investigated with experiments on the Nova laser facility at LLNL. It was found that in a flowing plasma, energy is transferred between two crossing laser beams, and this may have deleterious consequences for energy balance and ignition in NIF. Possible solutions to this problem are presented. A recently-proposed alternative to standard laser-driven fusion, the ''fast ignitor'' concept, is also experimentally addressed in this dissertation. Many of the laser-plasma interactions necessary for the success of the fast ignitor have not previously been explored at the relevant laser intensities. Specifically, the transfer of high-intensity laser energy to electrons at solid-target interfaces is addressed. 20-30% conversion efficiencies into forward-propagated electrons were measured, along with an average electron energy that varied with the type of target material. The directionality of the electrons was also measured, revealing an apparent beaming of the highest energy electrons. This work was extended to various intensities and pulse lengths and a

  11. Inertial confinement fusion research and development studies. Final report, October 1979-August 1980

    SciTech Connect

    Bullis, R.; Finkelman, M.; Leng, J.; Luzzi, T.; Ojalvo, I.; Powell, E.; Sedgley, D.

    1980-08-01

    These Inertial Confinement Fusion (ICF) research and development studies were selected for structural, thermal, and vacuum pumping analyses in support of the High Yield Lithium Injection Fusion Energy (HYLIFE) concept development. An additional task provided an outlined program plan for an ICF Engineering Test Facility, using the HYLIFE concept as a model, although the plan is generally applicable to other ICF concepts. The HYLIFE is one promising type of ICF concept which features a falling array of liquid lithium jets. These jets surround the fusion reaction to protect the first structural wall (FSW) of the vacuum chamber by absorbing the fusion energy, and to act as the tritium breeder. The fusion energy source is a deuterium-tritium pellet injected into the chamber every second and driven by laser or heavy ion beams. The studies performed by Grumman have considered the capabilities of specific HYLIFE features to meet life requirements and the requirement to recover to preshot conditions prior to each subsequent shot. The components under investigation were the FSW which restrains the outward motion of the liquid lithium, the nozzle plate which forms the falling jet array, the graphite shield which is in direct top view of the fusion pellet, and the vacuum pumping system. The FSW studies included structural analysis, and definition of an experimental program to validate computer codes describing lithium motion and the resulting impact on the wall.

  12. Inertial confinement fusion. 1995 ICF annual report, October 1994--September 1995

    SciTech Connect

    1996-06-01

    Lawrence Livermore National Laboratory`s (LLNL`s) Inertial Confinement Fusion (ICF) Program is a Department of Energy (DOE) Defense Program research and advanced technology development program focused on the goal of demonstrating thermonuclear fusion ignition and energy gain in the laboratory. During FY 1995, the ICF Program continued to conduct ignition target physics optimization studies and weapons physics experiments in support of the Defense Program`s stockpile stewardship goals. It also continued to develop technologies in support of the performance, cost, and schedule goals of the National Ignition Facility (NIF) Project. The NIF is a key element of the DOE`s Stockpile Stewardship and Management Program. In addition to its primary Defense Program goals, the ICF Program provides research and development opportunities in fundamental high-energy-density physics and supports the necessary research base for the possible long-term application to inertial fusion energy (IFE). Also, ICF technologies have had spin-off applications for industrial and governmental use. Selected papers are indexed separately for inclusion in the Energy Science and Technology Database.

  13. Free-electron laser-fusion drivers for inertial-confinement fusion

    SciTech Connect

    Schlitt, L.G.

    1980-01-01

    The use of tapered wiggler, free electron lasers as drivers for inertial confinement fusion requires an electron beam source which must meet specific and stringent requirements. The characteristics of ICF targets are combined with those of the free electron laser to obtain a general set of requirements and to define parameter tradeoffs. In particular, low beam emittance is essential to the system. A conceptual point design of an ICF-FEL driver is discussed.

  14. Inertial confinement fusion quarterly report, April--June 1994. Volume 4, Number 3

    SciTech Connect

    Shaw, M.J.

    1994-06-01

    This issue of the ICF Quarterly contains six articles covering a wide range of activities within the Inertial Confinement Fusion (ICF) Program. It concentrates on target design; theoretical spectral analysis of ICF capsule surfaces; laser fusion experimental methods; and an alternative ICF design, based on ultrafast, ultrapowerful lasers. A key issue for the success of the ICF process is the hydrodynamic stability of the imploding capsule. There are two primary sources of instability growth in the ICF process: (1) asymmetries in the x-ray flux that drive the compression lead to asymmetric in the imploding surface; (2) imperfections on the capsule surface can grow into large perturbations, degrading the capsule performance. In recent years, a great deal of effort, both experimentally and theoretically, has been spent to enhance the Program`s ability to measure, model, and minimize instability growth during an implosion. Four the articles in this issue discuss this subject.

  15. Plasma Stopping Power Measurements Relevant to Inertial Confinement Fusion

    NASA Astrophysics Data System (ADS)

    McEvoy, Aaron; Herrmann, Hans; Kim, Yongho; Hoffman, Nelson; Schmitt, Mark; Rubery, Michael; Garbett, Warren; Horsfield, Colin; Gales, Steve; Zylstra, Alex; Gatu Johnson, Maria; Frenje, Johan; Petrasso, Richard; Marshall, Frederic; Batha, Steve

    2015-11-01

    Ignition in inertial confinement fusion (ICF) experiments may be achieved if the alpha particle energy deposition results in a thermonuclear burn wave induced in the dense DT fuel layer surrounding the hotspot. As such, understanding the physics of particle energy loss in a plasma is of critical importance to designing ICF experiments. Experiments have validated various stopping power models under select ne and Te conditions, however there remain unexplored regimes where models predict differing rates of energy deposition. An upcoming experiment at the Omega laser facility will explore charged particle stopping in CH plastic capsule ablators across a range of plasma conditions (ne between 1024 cm-3 and 1025 cm-3 and Te on the order of hundreds of eV). Plasma conditions will be measured using x-ray and gamma ray diagnostics, while plasma stopping power will be measured using charged particle energy loss measurements. Details on the experiment and the theoretical models to be tested will be presented.

  16. Development of Compton radiography of inertial confinement fusion implosions

    SciTech Connect

    Tommasini, R.; Hatchett, S. P.; Hey, D. S.; Iglesias, C.; Izumi, N.; Koch, J. A.; Landen, O. L.; MacKinnon, A. J.; Sorce, C.; Delettrez, J. A.; Glebov, V. Yu.; Sangster, T. C.; Stoeckl, C.

    2011-05-15

    An important diagnostic tool for inertial confinement fusion will be time-resolved radiographic imaging of the dense cold fuel surrounding the hot spot. The measurement technique is based on point-projection radiography at photon energies from 60 to 200 keV where the Compton effect is the dominant contributor to the opacity of the fuel or pusher. We have successfully applied this novel Compton radiography technique to the study of the final compression of directly driven plastic capsules at the OMEGA facility [T. R. Boehly et al., Opt. Commun. 133, 495 (1997)]. The radiographs have a spatial and temporal resolution of {approx}10 {mu}m and {approx}10 ps, respectively. A statistical accuracy of {approx}0.5% in transmission per resolution element is achieved, allowing localized measurements of areal mass densities to 7% accuracy. The experimental results show 3D nonuniformities and lower than 1D expected areal densities attributed to drive asymmetries and hydroinstabilities.

  17. Antimatter Assisted Inertial Confinement Fusion Propulsion Systems for Interstellar Missions

    NASA Astrophysics Data System (ADS)

    Halyard, R. J.

    Current developments such as the Ion Compressed Antimatter Nuclear (ICAN-II) propulsion system proposed by the Pennsylvania State University Center for Space Propulsion Engineering open the way to the possible use of available supplies of antiprotons to power antimatter assisted inertial confinement fusion (AAICF) propulsion systems for interstellar missions. Analysis indicates that light weight AAICF propulsion systems with specific impulses in excess of seven hundred thousand seconds may be feasible within the next 30 years. AAICF should prove to be the optimum propulsion system since it possesses high thrust, low weight and high exhaust velocity. The purpose of this paper is to evaluate the potential of AAICF propulsion for interstellar missions such as NASA Administrator Dan Goldin's Alpha Centauri Flyby and a Barnard's Star Orbital Mission, and to compare these projections with previous performance estimates for ICF Laser Beam propulsion systems.

  18. Development of Compton radiography of inertial confinement fusion implosionsa)

    NASA Astrophysics Data System (ADS)

    Tommasini, R.; Hatchett, S. P.; Hey, D. S.; Iglesias, C.; Izumi, N.; Koch, J. A.; Landen, O. L.; MacKinnon, A. J.; Sorce, C.; Delettrez, J. A.; Glebov, V. Yu.; Sangster, T. C.; Stoeckl, C.

    2011-05-01

    An important diagnostic tool for inertial confinement fusion will be time-resolved radiographic imaging of the dense cold fuel surrounding the hot spot. The measurement technique is based on point-projection radiography at photon energies from 60 to 200 keV where the Compton effect is the dominant contributor to the opacity of the fuel or pusher. We have successfully applied this novel Compton radiography technique to the study of the final compression of directly driven plastic capsules at the OMEGA facility [T. R. Boehly et al., Opt. Commun. 133, 495 (1997)]. The radiographs have a spatial and temporal resolution of ˜10 μm and ˜10 ps, respectively. A statistical accuracy of ˜0.5% in transmission per resolution element is achieved, allowing localized measurements of areal mass densities to 7% accuracy. The experimental results show 3D nonuniformities and lower than 1D expected areal densities attributed to drive asymmetries and hydroinstabilities.

  19. Development of Compton Radiography Diagnostics for Inertial Confinement Fusion Implosions

    SciTech Connect

    Tommasini, R; Hatchett, S P; Hey, D S; Izumi, N; Koch, J A; Landen, O L; Mackinnon, A J; Delettrez, J; Glebov, V; Stoeckl, C

    2010-11-16

    An important diagnostic tool for inertial confinement fusion will be time-resolved radiographic imaging of the dense cold fuel surrounding the hot spot. The measurement technique is based on point-projection radiography at photon energies from 60-200 keV where the Compton effect is the dominant contributor to the opacity of the fuel or pusher. We have successfully applied this novel Compton Radiography technique to the study of the final compression of directly driven plastic capsules at the OMEGA facility. The radiographs have a spatial and temporal resolution of {approx}10 {micro}m and {approx}10ps, respectively. A statistical accuracy of {approx}0.5% in transmission per resolution element is achieved, allowing localized measurements of areal mass densities to 7% accuracy. The experimental results show 3D non-uniformities and lower than 1D expected areal densities attributed to drive asymmetries and hydroinstabilities.

  20. Strong Coupling and Degeneracy Effects in Inertial Confinement Fusion Implosions

    SciTech Connect

    Hu, S.X.; Militzer, B.; Goncharov, V.N.; Skupsky, S.

    2010-06-10

    Accurate knowledge about the equation of state (EOS) of deuterium is critical to inertial confinement fusion (ICF). Low-adiabat ICF implosions routinely access strongly coupled and degenerate plasma conditions. Using the path integral Monte Carlo method, we have derived a first-principles EOS (FPEOS) table of deuterium. It is the first ab initio EOS table which completely covers typical ICF implosion trajectory in the density and temperature ranges of rho = 0.002–1596 g/cm^3 and T = 1.35 eV–5.5 keV. Discrepancies in internal energy and pressure have been found in strongly coupled and degenerate regimes with respect to SESAME EOS. Hydrodynamics simulations of cryogenic ICF implosions using the FPEOS table have indicated significant differences in peak density, areal density, and neutron yield relative to SESAME simulations.

  1. Production of {sup 13}N Via Inertial Electrostatic Confinement Fusion

    SciTech Connect

    Weidner, J.W.; Kulcinski, G.L.; Santarius, J.F.; Ashley, R.P.; Piefer, G.; Cipiti, B.; Radel, R.; Murali, S. Krupakar

    2003-09-15

    This paper describes a proof of principle experiment to produce {sup 13}N using an inertial electrostatic confinement (IEC) fusion device. This radioisotope is often used in positron emission tomography scans to image the heart. The 10-minute half-life of {sup 13}N limits its use to those areas and clinics that possess an accelerator. A portable IEC device could be brought to remote locations, however, and produce short-lived PET isotopes on-site. Using the 14.7 MeV protons produced from the D-{sup 3}He fuel cycle, University of Wisconsin IEC device was used to produce approximately 4 - 8 Bq of {sup 13}N during two separate experiments.

  2. Integrated diagnostic analysis of inertial confinement fusion capsule performancea)

    NASA Astrophysics Data System (ADS)

    Cerjan, Charles; Springer, Paul T.; Sepke, Scott M.

    2013-05-01

    A conceptual model is developed for typical inertial confinement fusion implosion conditions that integrates available diagnostic information to determine the stagnation properties of the interior fill and surrounding shell. Assuming pressure equilibrium at peak compression and invoking radiative and equation-of-state relations, the pressure, density, and electron temperature are obtained by optimized fitting of the experimental output to smooth, global functional forms. Typical observational data that may be used includes x-ray self-emission, directional neutron time-of-flight signals, neutron yield, high-resolution x-ray spectra, and radiographic images. This approach has been validated by comparison with radiation-hydrodynamic simulations, producing semi-quantitative agreement. Model results implicate poor kinetic energy coupling to the hot core as the primary cause of the observed low thermonuclear burn yields.

  3. Design considerations for an inertial confinement fusion reactor power plant

    SciTech Connect

    Massey, J.V.; Simpson, J.E.

    1981-08-10

    To further define the engineering and economic concerns for inertial confinement fusion reactors (ICR's), a conceptual design study was performed by Bechtel Group Incorporated under the direction of Lawrence Livermore National Laboratory (LLNL). The study examined alternatives to the LLNL HYLIFE concept and expanded the previous balance of plant design to incorporate information from recent liquid metal cooled fast breeder reactor (LMFBR) power plant studies. The majority of the effort was to incorporate present laser and target physics models into a reactor design with a low coolant flowrate and a high driver repetition rate. An example of such a design is the LLNL JADE concept. In addition to producing a power plant design for LLNL using the JADE example, Bechtel has also examined the applicability of the EAGLE (Energy Absorbing Gas Lithium Ejector) concept.

  4. Passive Spectroscopic Diagnostics for Magnetically-confined Fusion Plasmas

    SciTech Connect

    Stratton, B. C.; Biter, M.; Hill, K. W.; Hillis, D. L.; Hogan, J. T.

    2007-07-18

    Spectroscopy of radiation emitted by impurities and hydrogen isotopes plays an important role in the study of magnetically-confined fusion plasmas, both in determining the effects of impurities on plasma behavior and in measurements of plasma parameters such as electron and ion temperatures and densities, particle transport, and particle influx rates. This paper reviews spectroscopic diagnostics of plasma radiation that are excited by collisional processes in the plasma, which are termed 'passive' spectroscopic diagnostics to distinguish them from 'active' spectroscopic diagnostics involving injected particle and laser beams. A brief overview of the ionization balance in hot plasmas and the relevant line and continuum radiation excitation mechanisms is given. Instrumentation in the soft X-ray, vacuum ultraviolet, ultraviolet, visible, and near-infrared regions of the spectrum is described and examples of measurements are given. Paths for further development of these measurements and issues for their implementation in a burning plasma environment are discussed.

  5. Fuel Encapsulation for Inertial Electrostatic Confinement Nuclear Fusion Reactors

    NASA Astrophysics Data System (ADS)

    Macleod, C.

    Inertial Electrostatic Confinement (IEC) is an approach to nuclear fusion which utilises the properties of electrostatically accelerated ion-beams instead of hot plasmas. The best known device which uses the principle is the Farnsworth-Hirsch fusor. It has been argued that such devices have some potential advantages in spaceflight and in-particular as power-supplies for trans-atmospheric propulsion. This paper builds on previous work in the field and focuses on how the fixing of the fuel for such reactors in a solid, liquid or encapsulated form may provide a high enough energy-density to make such devices practical power sources. Several methods of fixing the fuel are discussed; theoretical calculations are presented and applicable literature is reviewed. Finally, there is a discussion of practical issues and feasibility, together with suggestions for further work.

  6. Polyvinyl alcohol coating of polystyrene inertial confinement fusion targets

    NASA Technical Reports Server (NTRS)

    Annamalai, P.; Lee, M. C.; Crawley, R. L.; Downs, R. L.

    1985-01-01

    An inertial confinement fusion (ICF) target made of polystyrene is first levitated in an acoustic field. The surface of the target is then etched using an appropriate solution (e.g., cyclohexane) to enhance the wetting characteristics. A specially prepared polyvinyl alcohol solution is atomized using an acoustic atomizer and deposited on the surface of the target. The solution is air dried to form a thin coating (2 microns) on the target (outside diameter of about 350-850 microns). Thicker coatings are obtained by repeated applications of the coating solutions. Preliminary results indicate that uniform coatings may be achievable on the targets with a background surface smoothness in the order of 1000 A.

  7. The technology benefits of inertial confinement fusion research

    SciTech Connect

    Powell, H T

    1999-05-26

    radioactive by-products. Meeting these challenges will produce spin-off value of enormous magnitude. By exploring the technology spin-offs of the inertial fusion community to date, we can glimpse the expected future rewards from an IFE program.

  8. Control of a laser inertial confinement fusion-fission power plant

    DOEpatents

    Moses, Edward I.; Latkowski, Jeffery F.; Kramer, Kevin J.

    2015-10-27

    A laser inertial-confinement fusion-fission energy power plant is described. The fusion-fission hybrid system uses inertial confinement fusion to produce neutrons from a fusion reaction of deuterium and tritium. The fusion neutrons drive a sub-critical blanket of fissile or fertile fuel. A coolant circulated through the fuel extracts heat from the fuel that is used to generate electricity. The inertial confinement fusion reaction can be implemented using central hot spot or fast ignition fusion, and direct or indirect drive. The fusion neutrons result in ultra-deep burn-up of the fuel in the fission blanket, thus enabling the burning of nuclear waste. Fuels include depleted uranium, natural uranium, enriched uranium, spent nuclear fuel, thorium, and weapons grade plutonium. LIFE engines can meet worldwide electricity needs in a safe and sustainable manner, while drastically shrinking the highly undesirable stockpiles of depleted uranium, spent nuclear fuel and excess weapons materials.

  9. Innovative approaches to inertial confinement fusion reactors: Final report

    SciTech Connect

    Bourque, R.F.; Schultz, K.R.

    1986-11-01

    Three areas of innovative approaches to inertial confinement fusion (ICF) reactor design are given. First, issues pertaining to the Cascade reactor concept are discussed. Then, several innovative concepts are presented which attempt to directly recover the blast energy from a fusion target. Finally, the Turbostar concept for direct recovery of that energy is evaluated. The Cascade issues discussed are combustion of the carbon granules in the event of air ingress, the use of alternate granule materials, and the effect of changes in carbon flow on details of the heat exchanger. Carbon combustion turns out to be a minor problem. Four ICF innovative concepts were considered: a turbine with ablating surfaces, a liquid piston system, a wave generator, and a resonating pump. In the final analysis, none show any real promise. The Turbostar concept of direct recovery is a very interesting idea and appeared technically viable. However, it shows no efficiency gain or any decrease in capital cost compared to reactors with conventional thermal conversion systems. Attempts to improve it by placing a close-in lithium sphere around the target to increase gas generation increased efficiency only slightly. It is concluded that these direct conversion techniques require thermalization of the x-ray and debris energy, and are Carnot limited. They therefore offer no advantage over existing and proposed methods of thermal energy conversion or direct electrical conversion.

  10. Inertial confinement fusion based on the ion-bubble trigger

    SciTech Connect

    Jafari, S. Nilkar, M.; Ghasemizad, A.; Mehdian, H.

    2014-10-15

    Triggering the ion-bubble in an inertial confinement fusion, we have developed a novel scheme for the fast ignition. This scheme relies on the plasma cavitation by the wake of an intense laser pulse to generate an ion-bubble. The bubble acts both as an intense electron accelerator and as an electron wiggler. Consequently, the accelerated electrons trapped in the bubble can emit an intense tunable laser light. This light can be absorbed by an ablation layer on the outside surface of the ignition capsule, which subsequently drills it and thereby produces a guide channel in the pellet. Finally, the relativistic electron beam created in the bubble is guided through the channel to the high density core igniting the fusion fuel. The normalized beam intensity and beam energy required for triggering the ignition have been calculated when core is heated by the e-beam. In addition, through solving the momentum transfer, continuity and wave equations, a dispersion relation for the electromagnetic and space-charge waves has been analytically derived. The variations of growth rate with the ion-bubble density and electron beam energy have been illustrated. It is found that the growth rates of instability are significantly controlled by the ions concentration and the e-beam energy in the bubble.

  11. Alpha Heating and Burning Plasmas in Inertial Confinement Fusion

    NASA Astrophysics Data System (ADS)

    Christopherson, A. R.

    2015-11-01

    In inertial confinement fusion, a spherical capsule of cryogenic DT is accelerated inward at a high velocity. Near stagnation, a dense hot spot is formed where the deuterium and tritium ions begin to fuse, creating a 3.5-MeV alpha particle per reaction. These alpha particles deposit energy back into the plasma, thereby increasing the pressure, temperature, and reaction rate. This feedback process is called ``alpha heating,'' and ignition is a direct consequence of this thermal instability. The onset of a burning-plasma regime occurs when the total alpha-particle energy produced exceeds the shell compression work. Using an analytic compressible-shell model for the implosion, it is found that the onset of the burning-plasma regime is a unique function of the neutron yield enhancement caused by alpha particles for any target, direct or indirect drive. This yield enhancement can then be inferred from experimentally measureable quantities, such as the Lawson parameter. From this analysis, the onset of a burning plasma occurs at yields exceeding 50 kJ for implosions at the National Ignition Facility. This material is based upon work supported by the Department of Energy National Nuclear Security Administration under Award Number DE-NA0001944 and DE-FC02-04ER54789 (Fusion Science Center).

  12. Fusion Breeder Program interim report

    SciTech Connect

    Moir, R.; Lee, J.D.; Neef, W.

    1982-06-11

    This interim report for the FY82 Fusion Breeder Program covers work performed during the scoping phase of the study, December, 1981-February 1982. The goals for the FY82 study are the identification and development of a reference blanket concept using the fission suppression concept and the definition of a development plan to further the fusion breeder application. The context of the study is the tandem mirror reactor, but emphasis is placed upon blanket engineering. A tokamak driver and blanket concept will be selected and studied in more detail during FY83.

  13. Cluster ion beam polishing for inertial confinement fusion target capsules

    SciTech Connect

    McEachern, R., LLNL

    1998-06-09

    Targets for Inertial Confinement Fusion (ICF) typically consist of a hollow, spherical capsule filled with a mixture of hydrogen isotopes. Typically, these capsules are irradiated by short, intense pulses of either laser light (``direct drive``) or laser-generated. x-rays (``indirect drive``), causing them to implode This compresses and heats the fuel, leading to thermonuclear fusion. This process is highly sensitive to hydrodynamic (e.g., Rayleigh-Taylor) instabilities, which can be initiated by imperfections in the target. Thus, target capsules must be spherical and smooth One of the lead capsule designs for the National Ignition Facility, a 1.8 MJ laser being built at Livermore, calls for a 2-mm- diam capsule with a 150-{micro}m-thick copper-doped beryllium wall. These capsules can be fabricated by sputter depositing the metal onto a spherical plastic mandrel. This results in surfaces with measured Rq`s of 50 to 150 nm, as measured with an atomic force microscope For optimal performance the roughness should be below 10 nm rms We have begun studying the use of ion cluster beam polishing as a means of improving the surface finish of as-deposited capsules In this approach, a batch of capsules would be agitated in a bounce pan inside a vacuum chamber during exposure to the cluster beam. This would ensure a uniform beam dose around the capsule. We have performed preliminary experiments on both Be flats and on a stationary Be capsule On the capsule, the measured Rq went from 64 nm before polishing to 15 nm after This result was obtained without any effort at process optimization. Similar smoothing was observed on the planar samples

  14. Inertial Confinement Fusion: Quarterly report, April-June 1996

    SciTech Connect

    Correll, D.

    1996-06-01

    The lead article, `Ion-beam propagation in a low-density reactor chamber for heavy-ion inertial fusion` (p. 89), explores the ability of heavy-ion beams to be adequately transported and focused in an IFE reactor. The next article, `Efficient production and applications of 2- to 10-keV x rays by laser-heated underdense radiators` (p. 96), explores the ability of the NIF to produce sufficient high-energy x rays for diagnostic backlighting, target preheating, or uniform irradiation of large test objects for Nuclear Weapons Effects Testing. For capsule implosion experiments, the increasing energies and distances involved in the NIF compared to Nova require the development of new diagnostics methods. The article `Fusion reaction-rate measurements--Nova and NIF` (p. 115) first reviews the use of time-resolved neutron measurements on Nova to monitor fusion burn histories and then explores the limitations of that technique, principally Doppler broadening, for the proposed NIF. It also explores the use of gamma rays on Nova, thereby providing a proof-of-principle for using gamma rays for monitoring fusion burn histories on the NIF. The articles `The energetics of gas-filled hohlraums` (p. 110) and `Measurements of laser- speckle-induced perturbations in laser-driven foils` (p. 123) report measurements on Nova of two important aspects of implosion experiments. The first characterizes the amount of energy lost from a hohlraum by stimulated Brillouin and Raman scattering as a function of gas fill and laser-beam uniformity. The second of these articles shows that the growth of density nonuniformities implanted on smooth capsule surfaces by laser speckle can be correlated with the effects of physical surface roughness. The article `Laser-tissue interaction modeling with the LATIS computer program` (p. 103) explores the use of modeling to enhance the effectiveness--maximize desired effects and minimize collateral damage--of lasers for medical purposes.

  15. Adiabat-shaping in indirect drive inertial confinement fusion

    NASA Astrophysics Data System (ADS)

    Baker, K. L.; Robey, H. F.; Milovich, J. L.; Jones, O. S.; Smalyuk, V. A.; Casey, D. T.; MacPhee, A. G.; Pak, A.; Celliers, P. M.; Clark, D. S.; Landen, O. L.; Peterson, J. L.; Berzak-Hopkins, L. F.; Weber, C. R.; Haan, S. W.; Döppner, T. D.; Dixit, S.; Giraldez, E.; Hamza, A. V.; Jancaitis, K. S.; Kroll, J. J.; Lafortune, K. N.; MacGowan, B. J.; Moody, J. D.; Nikroo, A.; Widmayer, C. C.

    2015-05-01

    Adiabat-shaping techniques were investigated in indirect drive inertial confinement fusion experiments on the National Ignition Facility as a means to improve implosion stability, while still maintaining a low adiabat in the fuel. Adiabat-shaping was accomplished in these indirect drive experiments by altering the ratio of the picket and trough energies in the laser pulse shape, thus driving a decaying first shock in the ablator. This decaying first shock is designed to place the ablation front on a high adiabat while keeping the fuel on a low adiabat. These experiments were conducted using the keyhole experimental platform for both three and four shock laser pulses. This platform enabled direct measurement of the shock velocities driven in the glow-discharge polymer capsule and in the liquid deuterium, the surrogate fuel for a DT ignition target. The measured shock velocities and radiation drive histories are compared to previous three and four shock laser pulses. This comparison indicates that in the case of adiabat shaping the ablation front initially drives a high shock velocity, and therefore, a high shock pressure and adiabat. The shock then decays as it travels through the ablator to pressures similar to the original low-adiabat pulses when it reaches the fuel. This approach takes advantage of initial high ablation velocity, which favors stability, and high-compression, which favors high stagnation pressures.

  16. Adiabat-shaping in indirect drive inertial confinement fusion

    SciTech Connect

    Baker, K. L.; Robey, H. F.; Milovich, J. L.; Jones, O. S.; Smalyuk, V. A.; Casey, D. T.; MacPhee, A. G.; Pak, A.; Celliers, P. M.; Clark, D. S.; Landen, O. L.; Peterson, J. L.; Berzak-Hopkins, L. F.; Weber, C. R.; Haan, S. W.; Döppner, T. D.; Dixit, S.; Hamza, A. V.; Jancaitis, K. S.; Kroll, J. J.; and others

    2015-05-15

    Adiabat-shaping techniques were investigated in indirect drive inertial confinement fusion experiments on the National Ignition Facility as a means to improve implosion stability, while still maintaining a low adiabat in the fuel. Adiabat-shaping was accomplished in these indirect drive experiments by altering the ratio of the picket and trough energies in the laser pulse shape, thus driving a decaying first shock in the ablator. This decaying first shock is designed to place the ablation front on a high adiabat while keeping the fuel on a low adiabat. These experiments were conducted using the keyhole experimental platform for both three and four shock laser pulses. This platform enabled direct measurement of the shock velocities driven in the glow-discharge polymer capsule and in the liquid deuterium, the surrogate fuel for a DT ignition target. The measured shock velocities and radiation drive histories are compared to previous three and four shock laser pulses. This comparison indicates that in the case of adiabat shaping the ablation front initially drives a high shock velocity, and therefore, a high shock pressure and adiabat. The shock then decays as it travels through the ablator to pressures similar to the original low-adiabat pulses when it reaches the fuel. This approach takes advantage of initial high ablation velocity, which favors stability, and high-compression, which favors high stagnation pressures.

  17. Neutron imaging development for inertial confinement fusion experiments

    NASA Astrophysics Data System (ADS)

    Caillaud, Tony; Landoas, Olivier; Thfoin, Isabelle; Philippe, Franck; Casner, Alexis; Bourgade, Jean-Luc; Glebov, Vladimir; Marshall, Frederic J.; Sangster, Craig; Park, Hye Sook; Robey, Harry; Amendt, Peter

    2009-11-01

    Various failure mechanisms may limit fuel compression and ignition during Inertial Confinement Fusion (ICF) experiments with MegaJoule class lasers (e.g., the Laser M'egaJoule: LMJ and the National Ignition Facility: NIF). A Neutron Imaging System (NIS) may be used to determine the asymmetries in the hot core and the surrounding cold fuel shell. To reveal such asymmetries, a NIS must record both a primary (14 MeV) and a down-scattered (5-10 MeV) neutron image with high SNR and an image plane spatial resolution as low as 5 μm. We report on the continuing development of an NIS diagnostic at the OMEGA laser facility, using coded apertures. A new large neutron camera (150 mm entrance diameter: scaled for LMJ/NIF design) has been activated at OMEGA. This camera will allow 5 μm resolution for LMJ neutron source. We have tested a set of three detectors that can be used for various NIS diagnostic experiments on OMEGA from low yield (10^9-10^10 neutrons) low resolution (32 μm) measurements at 4 m from the neutron source to high yield (10^12-10^14 neutrons) high resolution (15 μm) measurements at 13 m. The low yield configuration allowed us to record, the first neutron image on an indirect drive shot with pure deuterium filled capsules.

  18. Production of hollow microspheres for inertial confinement fusion experiments

    SciTech Connect

    Cook, R.

    1994-12-01

    The targets used in inertial confinement fusion (ICF) experiments at the Lawrence Livermore National Laboratory are plastic capsules roughly 0.5 mm in diameter. The capsules, which typically have wall thicknesses from 20 to 60 {mu}m, must possess extraordinary symmetry and concentricity and must have surface finishes of less than 1000 {Angstrom} peak-to-valley variation over surface contours of from 10 to 100`s of {mu}m. This paper reviews the fabrication of these capsules, focusing on the production of the thin-walled polystyrene microshell mandrel around which the capsule is built. The relationship between the capsule characteristics, especially surface finish, and capsule performance is discussed, as are the methods of surface characterization and modification necessary for experiments designed to study the effects of surface roughness on implosion dynamics. Targets for the next generation of ICF facilities using more powerful laser drivers will have to be larger while meeting the same or even more stringent symmetry and surface finish requirements. Some of the technologies for meeting these needs are discussed briefly.

  19. Monte Carlo Particle Transport Capability for Inertial Confinement Fusion Applications

    SciTech Connect

    Brantley, P S; Stuart, L M

    2006-11-06

    A time-dependent massively-parallel Monte Carlo particle transport calculational module (ParticleMC) for inertial confinement fusion (ICF) applications is described. The ParticleMC package is designed with the long-term goal of transporting neutrons, charged particles, and gamma rays created during the simulation of ICF targets and surrounding materials, although currently the package treats neutrons and gamma rays. Neutrons created during thermonuclear burn provide a source of neutrons to the ParticleMC package. Other user-defined sources of particles are also available. The module is used within the context of a hydrodynamics client code, and the particle tracking is performed on the same computational mesh as used in the broader simulation. The module uses domain-decomposition and the MPI message passing interface to achieve parallel scaling for large numbers of computational cells. The Doppler effects of bulk hydrodynamic motion and the thermal effects due to the high temperatures encountered in ICF plasmas are directly included in the simulation. Numerical results for a three-dimensional benchmark test problem are presented in 3D XYZ geometry as a verification of the basic transport capability. In the full paper, additional numerical results including a prototype ICF simulation will be presented.

  20. Fusion Simulation Program

    SciTech Connect

    Project Staff

    2012-02-29

    Under this project, General Atomics (GA) was tasked to develop the experimental validation plans for two high priority ISAs, Boundary and Pedestal and Whole Device Modeling in collaboration with the theory, simulation and experimental communities. The following sections have been incorporated into the final FSP Program Plan (www.pppl.gov/fsp), which was delivered to the US Department of Energy (DOE). Additional deliverables by GA include guidance for validation, development of metrics to evaluate success and procedures for collaboration with experiments. These are also part of the final report.

  1. External Heat Transfer Coefficient Measurements on a Surrogate Indirect Inertial Confinement Fusion Target

    SciTech Connect

    Miles, Robin; Havstad, Mark; LeBlanc, Mary; Golosker, Ilya; Chang, Allan; Rosso, Paul

    2015-09-15

    External heat transfer coefficients were measured around a surrogate Indirect inertial confinement fusion (ICF) based on the Laser Inertial Fusion Energy (LIFE) design target to validate thermal models of the LIFE target during flight through a fusion chamber. Results indicate that heat transfer coefficients for this target 25-50 W/m2∙K are consistent with theoretically derived heat transfer coefficients and valid for use in calculation of target heating during flight through a fusion chamber.

  2. External Heat Transfer Coefficient Measurements on a Surrogate Indirect Inertial Confinement Fusion Target

    DOE PAGESBeta

    Miles, Robin; Havstad, Mark; LeBlanc, Mary; Golosker, Ilya; Chang, Allan; Rosso, Paul

    2015-09-15

    External heat transfer coefficients were measured around a surrogate Indirect inertial confinement fusion (ICF) based on the Laser Inertial Fusion Energy (LIFE) design target to validate thermal models of the LIFE target during flight through a fusion chamber. Results indicate that heat transfer coefficients for this target 25-50 W/m2∙K are consistent with theoretically derived heat transfer coefficients and valid for use in calculation of target heating during flight through a fusion chamber.

  3. National Mirror Fusion Program Plan

    SciTech Connect

    Gerich, C.A.

    1982-08-01

    This Plan is current as of August 1982. The major milestones listed herein represent an aggressive, success-oriented program paced primarily by technical results. Consistent with applicable government policies and the overall program planning of the Department's Office of Fusion Energy, this Plan assumes approval of the Mirror Program's next major step beyond MFTF-B - a deuterium-tritium (D-T) burning engineering reactor called the Fusion Power Demonstration (FPD) facility (formerly the Tandem Mirror Next Step). The near-term goal of the tandem mirror program is to lay the scientific and technical groundwork for an economically attractive, D-T fusion reactor design before the end of the 1980s. Construction of the FPD facility based on the tandem mirror could be initited around 1988. A second phase, complete with a nuclear power blanket demonstration, could be initiated in the mid-1990s, based on nuclear engineering data from a facility such as the Technology Demonstration Facility (TDF) described below. The outline of an acceptable tandem mirror reactor (TMR) design was first published in 1981, and will be further developed and described in the Mirror Advanced Reactor Study (MARS) during FY 1982-1983.

  4. Improved computational methods for simulating inertial confinement fusion

    NASA Astrophysics Data System (ADS)

    Fatenejad, Milad

    This dissertation describes the development of two multidimensional Lagrangian code for simulating inertial confinement fusion (ICF) on structured meshes. The first is DRACO, a production code primarily developed by the Laboratory for Laser Energetics. Several significant new capabilities were implemented including the ability to model radiative transfer using Implicit Monte Carlo [Fleck et al., JCP 8, 313 (1971)]. DRACO was also extended to operate in 3D Cartesian geometry on hexahedral meshes. Originally the code was only used in 2D cylindrical geometry. This included implementing thermal conduction and a flux-limited multigroup diffusion model for radiative transfer. Diffusion equations are solved by extending the 2D Kershaw method [Kershaw, JCP 39, 375 (1981)] to three dimensions. The second radiation-hydrodynamics code developed as part of this thesis is Cooper, a new 3D code which operates on structured hexahedral meshes. Cooper supports the compatible hydrodynamics framework [Caramana et al., JCP 146, 227 (1998)] to obtain round-off error levels of global energy conservation. This level of energy conservation is maintained even when two temperature thermal conduction, ion/electron equilibration, and multigroup diffusion based radiative transfer is active. Cooper is parallelized using domain decomposition, and photon energy group decomposition. The Mesh Oriented datABase (MOAB) computational library is used to exchange information between processes when domain decomposition is used. Cooper's performance is analyzed through direct comparisons with DRACO. Cooper also contains a method for preserving spherical symmetry during target implosions [Caramana et al., JCP 157, 89 (1999)]. Several deceleration phase implosion simulations were used to compare instability growth using traditional hydrodynamics and compatible hydrodynamics with/without symmetry modification. These simulations demonstrate increased symmetry preservation errors when traditional hydrodynamics

  5. Laser beam propagation through inertial confinement fusion hohlraum plasmasa)

    NASA Astrophysics Data System (ADS)

    Froula, D. H.; Divol, L.; Meezan, N. B.; Dixit, S.; Neumayer, P.; Moody, J. D.; Pollock, B. B.; Ross, J. S.; Suter, L.; Glenzer, S. H.

    2007-05-01

    A study of the laser-plasma interaction processes have been performed in plasmas that are created to emulate the plasma conditions in indirect drive inertial confinement fusion targets. The plasma emulator is produced in a gas-filled hohlraum; a blue 351-nm laser beam propagates along the axis of the hohlraum interacting with a high-temperature (Te=3.5keV), dense (ne=5×1020cm-3), long-scale length (L˜2mm) plasma. Experiments at these conditions have demonstrated that the interaction beam produces less than 1% total backscatter resulting in transmission greater than 90% for laser intensities less than I <2×1015Wcm-2. The bulk plasma conditions have been independently characterized using Thomson scattering where the peak electron temperatures are shown to scale with the hohlraum heater beam energy in the range from 2keV to 3.5keV. This feature has allowed us to determine the thresholds for both backscattering and filamentation instabilities; the former measured with absolutely calibrated full aperture backscatter and near backscatter diagnostics and the latter with a transmitted beam diagnostics. Comparing the experimental results with detailed gain calculations for the onset of significant laser scattering processes shows a stimulated Brillouin scattering threshold (R=10%) for a linear gain of 15; these high temperature, low density experiments produce plasma conditions comparable to those along the outer beams in ignition hohlraum designs. By increasing the gas fill density (ne=1021cm-3) in these targets, the inner beam ignition hohlraum conditions are accessed. In this case, stimulated Raman scattering dominates the backscattering processes and we show that scattering is small for gains less than 20 which can be achieved through proper choice of the laser beam intensity.

  6. Direct-drive inertial confinement fusion: A review

    NASA Astrophysics Data System (ADS)

    Craxton, R. S.; Anderson, K. S.; Boehly, T. R.; Goncharov, V. N.; Harding, D. R.; Knauer, J. P.; McCrory, R. L.; McKenty, P. W.; Meyerhofer, D. D.; Myatt, J. F.; Schmitt, A. J.; Sethian, J. D.; Short, R. W.; Skupsky, S.; Theobald, W.; Kruer, W. L.; Tanaka, K.; Betti, R.; Collins, T. J. B.; Delettrez, J. A.; Hu, S. X.; Marozas, J. A.; Maximov, A. V.; Michel, D. T.; Radha, P. B.; Regan, S. P.; Sangster, T. C.; Seka, W.; Solodov, A. A.; Soures, J. M.; Stoeckl, C.; Zuegel, J. D.

    2015-11-01

    The direct-drive, laser-based approach to inertial confinement fusion (ICF) is reviewed from its inception following the demonstration of the first laser to its implementation on the present generation of high-power lasers. The review focuses on the evolution of scientific understanding gained from target-physics experiments in many areas, identifying problems that were demonstrated and the solutions implemented. The review starts with the basic understanding of laser-plasma interactions that was obtained before the declassification of laser-induced compression in the early 1970s and continues with the compression experiments using infrared lasers in the late 1970s that produced thermonuclear neutrons. The problem of suprathermal electrons and the target preheat that they caused, associated with the infrared laser wavelength, led to lasers being built after 1980 to operate at shorter wavelengths, especially 0.35 μm—the third harmonic of the Nd:glass laser—and 0.248 μm (the KrF gas laser). The main physics areas relevant to direct drive are reviewed. The primary absorption mechanism at short wavelengths is classical inverse bremsstrahlung. Nonuniformities imprinted on the target by laser irradiation have been addressed by the development of a number of beam-smoothing techniques and imprint-mitigation strategies. The effects of hydrodynamic instabilities are mitigated by a combination of imprint reduction and target designs that minimize the instability growth rates. Several coronal plasma physics processes are reviewed. The two-plasmon-decay instability, stimulated Brillouin scattering (together with cross-beam energy transfer), and (possibly) stimulated Raman scattering are identified as potential concerns, placing constraints on the laser intensities used in target designs, while other processes (self-focusing and filamentation, the parametric decay instability, and magnetic fields), once considered important, are now of lesser concern for mainline direct

  7. Direct-drive inertial confinement fusion: A review

    SciTech Connect

    Craxton, R. S.; Anderson, K. S.; Boehly, T. R.; Goncharov, V. N.; Harding, D. R.; Knauer, J. P.; McKenty, P. W.; Myatt, J. F.; Short, R. W.; Skupsky, S.; Theobald, W.; Collins, T. J. B.; Delettrez, J. A.; Hu, S. X.; Marozas, J. A.; Maximov, A. V.; Michel, D. T.; Radha, P. B.; Regan, S. P.; Sangster, T. C.; and others

    2015-11-15

    The direct-drive, laser-based approach to inertial confinement fusion (ICF) is reviewed from its inception following the demonstration of the first laser to its implementation on the present generation of high-power lasers. The review focuses on the evolution of scientific understanding gained from target-physics experiments in many areas, identifying problems that were demonstrated and the solutions implemented. The review starts with the basic understanding of laser–plasma interactions that was obtained before the declassification of laser-induced compression in the early 1970s and continues with the compression experiments using infrared lasers in the late 1970s that produced thermonuclear neutrons. The problem of suprathermal electrons and the target preheat that they caused, associated with the infrared laser wavelength, led to lasers being built after 1980 to operate at shorter wavelengths, especially 0.35 μm—the third harmonic of the Nd:glass laser—and 0.248 μm (the KrF gas laser). The main physics areas relevant to direct drive are reviewed. The primary absorption mechanism at short wavelengths is classical inverse bremsstrahlung. Nonuniformities imprinted on the target by laser irradiation have been addressed by the development of a number of beam-smoothing techniques and imprint-mitigation strategies. The effects of hydrodynamic instabilities are mitigated by a combination of imprint reduction and target designs that minimize the instability growth rates. Several coronal plasma physics processes are reviewed. The two-plasmon–decay instability, stimulated Brillouin scattering (together with cross-beam energy transfer), and (possibly) stimulated Raman scattering are identified as potential concerns, placing constraints on the laser intensities used in target designs, while other processes (self-focusing and filamentation, the parametric decay instability, and magnetic fields), once considered important, are now of lesser concern for mainline

  8. Direct-drive inertial confinement fusion: A review

    DOE PAGESBeta

    Craxton, R. S.; Anderson, K. S.; Boehly, T. R.; Goncharov, V. N.; Harding, D. R.; Knauer, J. P.; McCrory, R. L.; McKenty, P. W.; Meyerhofer, D. D.; Myatt, J. F.; et al

    2015-11-25

    In this study, the direct-drive, laser-based approach to inertial confinement fusion (ICF) is reviewed from its inception following the demonstration of the first laser to its implementation on the present generation of high-power lasers. The review focuses on the evolution of scientific understanding gained from target-physics experiments in many areas, identifying problems that were demonstrated and the solutions implemented. The review starts with the basic understanding of laser–plasma interactions that was obtained before the declassification of laser-induced compression in the early 1970s and continues with the compression experiments using infrared lasers in the late 1970s that produced thermonuclear neutrons. Themore » problem of suprathermal electrons and the target preheat that they caused, associated with the infrared laser wavelength, led to lasers being built after 1980 to operate at shorter wavelengths, especially 0.35 um—the third harmonic of the Nd:glass laser—and 0.248 um (the KrF gas laser). The main physics areas relevant to direct drive are reviewed. The primary absorption mechanism at short wavelengths is classical inverse bremsstrahlung. Nonuniformities imprinted on the target by laser irradiation have been addressed by the development of a number of beam-smoothing techniques and imprint-mitigation strategies. The effects of hydrodynamic instabilities are mitigated by a combination of imprint reduction and target designs that minimize the instability growth rates. Several coronal plasma physics processes are reviewed. The two-plasmon–decay instability, stimulated Brillouin scattering (together with cross-beam energy transfer), and (possibly) stimulated Raman scattering are identified as potential concerns, placing constraints on the laser intensities used in target designs, while other processes (self-focusing and filamentation, the parametric decay instability, and magnetic fields), once considered important, are now of lesser

  9. Direct-drive inertial confinement fusion: A review

    SciTech Connect

    Craxton, R. S.; Anderson, K. S.; Boehly, T. R.; Goncharov, V. N.; Harding, D. R.; Knauer, J. P.; McCrory, R. L.; McKenty, P. W.; Meyerhofer, D. D.; Myatt, J. F.; Schmitt, A. J.; Sethian, J. D.; Short, R. W.; Skupsky, S.; Theobald, W.; Kruer, W. L.; Tanaka, K.; Betti, R.; Collins, T. J. B.; Delettrez, J. A.; Hu, S. X.; Marozas, J. A.; Maximov, A. V.; Michel, D. T.; Radha, P. B.; Regan, S. P.; Sangster, T. C.; Seka, W.; Solodov, A. A.; Soures, J. M.; Stoeckl, C.; Zuegel, J. D.

    2015-11-25

    In this study, the direct-drive, laser-based approach to inertial confinement fusion (ICF) is reviewed from its inception following the demonstration of the first laser to its implementation on the present generation of high-power lasers. The review focuses on the evolution of scientific understanding gained from target-physics experiments in many areas, identifying problems that were demonstrated and the solutions implemented. The review starts with the basic understanding of laser–plasma interactions that was obtained before the declassification of laser-induced compression in the early 1970s and continues with the compression experiments using infrared lasers in the late 1970s that produced thermonuclear neutrons. The problem of suprathermal electrons and the target preheat that they caused, associated with the infrared laser wavelength, led to lasers being built after 1980 to operate at shorter wavelengths, especially 0.35 um—the third harmonic of the Nd:glass laser—and 0.248 um (the KrF gas laser). The main physics areas relevant to direct drive are reviewed. The primary absorption mechanism at short wavelengths is classical inverse bremsstrahlung. Nonuniformities imprinted on the target by laser irradiation have been addressed by the development of a number of beam-smoothing techniques and imprint-mitigation strategies. The effects of hydrodynamic instabilities are mitigated by a combination of imprint reduction and target designs that minimize the instability growth rates. Several coronal plasma physics processes are reviewed. The two-plasmon–decay instability, stimulated Brillouin scattering (together with cross-beam energy transfer), and (possibly) stimulated Raman scattering are identified as potential concerns, placing constraints on the laser intensities used in target designs, while other processes (self-focusing and filamentation, the parametric decay instability, and magnetic fields), once considered important, are now of lesser concern for

  10. Inertial Confinement Fusion Quarterly Report: April--June 1993. Volume 3, Number 3

    SciTech Connect

    MacGowan, B.J.; Kotowski, M.; Schleich, D.

    1993-11-01

    This issue of the ICF Quarterly contains six articles describing recent advances in Lawrence Livermore National Laboratory`s inertial confinement fusion (ICF) program. The current emphasis of the ICF program is in support of DOE`s National Ignition Facility (NIF) initiative for demonstrating ignition and gain with a 1-2 MJ glass laser. The articles describe recent Nova experiments and investigations tailored towards enhancing understanding of the key physics and technological issues for the NIF. Titles of the articles are: development of large-aperture KDP crystals; inner-shell photo-ionized X-ray lasers; X-ray radiographic measurements of radiation-driven shock and interface motion in solid density materials; the role of nodule defects in laser-induced damage of multilayer optical coatings; techniques for Mbar to near-Gbar equation-of-state measurements with the Nova laser; parametric instabilities and laser-beam smoothing.

  11. Overview of University of Wisconsin Inertial-Electrostatic Confinement Fusion Research

    SciTech Connect

    Santarius, J.F.; Kulcinski, G.L.; Ashley, R.P.; Boris, D.R.; Cipiti, B.B.; Murali, S. Krupakar; Piefer, G.R.; Radel, R.F.; Radel, T.E.; Wehmeyer, A.L.

    2005-05-15

    In Inertial Electrostatic Confinement (IEC) devices, a voltage difference between concentric, nearly transparent spherical grids accelerates ions to fusion-relevant velocities. The University of Wisconsin (UW) operates two IEC devices: a cylindrical aluminum chamber and a spherical, water-cooled, stainless-steel chamber, with a power supply capable of 75 mA and 200 kV. The research program aims to generate fusion reaction products for various applications, including protons for creating radioisotopes for nuclear medicine and neutrons for detecting clandestine materials. Most IEC devices worldwide, including the UW devices, presently operate primarily in a pressure range (1-10 mtorr) that allows ions to make only a few passes through the core before they charge exchange and lose substantial energy or they collide with cathode grid wires. It is believed that fusion rates can be raised by operating at a pressure where neutral gas does not impede ion flow, and a helicon ion source has been developed to explore operation at pressures of {approx}0.05 mtorr. The UW IEC research group uses proton detectors, neutron detectors, residual gas analyzers, and spectroscopic diagnostics. New diagnostic techniques have also been developed, including eclipse disks to localize proton production and chordwires to estimate ion fluxes using power balance.

  12. SIRIUS-T: A study of a symmetrically illuminated inertial confinement fusion tritium production facility

    SciTech Connect

    Badger, B.; Sviatoslavksy, I.N.; Bruggink, D.; Engelstad, R.L.; Kulcinski, G.L.; Larsen, E.M.; Lovell, E.G.; MacFarlane, J.J.; Mogahed, E.A.; Moses, G.A.; Moucha, A.; Peterson, R.R.; Powers, J.; Sawan, M.E.; Wittenberg, L.J.

    1990-12-01

    The aging US tritium production reactors are slowly being phased out and the US Department of Energy has initiated a New Production Reactors Program'' which will provide for the design, construction and operation of new facilities for the production of tritium and other special nuclear materials. Preliminary requirements are currently being prepared, leading to construction and operation by the year 2000. Unfortunately, inertial confinement fusion (ICF) cannot possibly be ready to perform such a task on this short time scale. However, it is instructive to see how well it can do in producing tritium when ICF has been demonstrated and a comparison with the proposed production schemes is conducted here. SIRIUS-T is conceptual design study of a tritium production facility utilizing direct drive symmetrically illuminated inertial confinement fusion. The T'' designation distinguishes it from SIRIUS-M, a materials facility, and SIRIUS-C, a commercial power plant. As in any other fusion related design study, a certain amount of technical extrapolation has been made in SIRIUS-T. It should be said early on, however, that in areas of uncertainty, we have always taken the conservative approach. This is evident in our choice of target gain, number of beams selected for symmetric illumination and elsewhere throughout the study. In performing the economic analysis we have also attempted to err on the conservative side. This too is evident in our costing of the driver and the reactor chamber. For these reasons, we feel that this study projects enough confidence as to make it worthy of comparison with the other proposed production systems.

  13. Overview of the Lockheed Martin Compact Fusion Reactor (CFR) Program

    NASA Astrophysics Data System (ADS)

    McGuire, Thomas

    2015-11-01

    The Lockheed Martin Compact Fusion Reactor (CFR) Program endeavors to quickly develop a compact fusion power plant with favorable commercial economics and military utility. An overview of the concept and its diamagnetic, high beta magnetically encapsulated linear ring cusp confinement scheme will be given. The analytical model of the major loss mechanisms and predicted performance will be discussed, along with the major physics challenges. Key features of an operational CFR reactor will be highlighted. The proposed developmental path following the current experimental efforts will be presented. ©2015 Lockheed Martin Corporation. All Rights Reserved.

  14. Plasma kinetic effects on interfacial mix in settings relevant to inertial confinement fusion and laboratory experiments

    NASA Astrophysics Data System (ADS)

    Yin, L.; Albright, B. J.; Bergen, B.; Bowers, K. J.; Vold, E. L.; Molvig, K.; Fernández, J. C.; Bang, W.; Bradley, P. A.; Gautier, D. C.; Hamilton, C. E.; Palaniyappan, S.; Santiago Cordoba, M. A.; Hegelich, B. M.; Dyer, G.; Roycroft, R.

    2015-11-01

    Mixing of high-Z/low-Z interfaces in dense plasma media is a problem of importance for understanding mix in inertial confinement fusion experiments and recent experiments at the LANL Trident facility. In this presentation, we apply the VPIC particle-in-cell code with a binary collision model to explore kinetic effects of the atomic mixing. Comparisons are made to published analytic theory and hybrid modeling results and conditions are identified under which plasma kinetic behavior may lead to anomalously rapid atomic mixing. Work performed under the auspices of the U.S. DOE by the LANS, LLC, Los Alamos National Laboratory under Contract No. DE-AC52-06NA25396. Funding provided by the Los Alamos National Laboratory Directed Research and Development Program.

  15. Advances in Inertial Confinement Fusion at the National Ignition Facility (NIF)

    SciTech Connect

    Moses, E

    2009-10-15

    The 192-beam National Ignition Facility (NIF) at the Lawrence Livermore National Laboratory (LLNL) in Livermore, CA, is now operational and conducting experiments. NIF, the flagship facility of the U.S. Inertial Confinement Fusion (ICF) Program, will achieve high-energy-density conditions never previously obtained in the laboratory - temperatures over 100 million K, densities of 1,000 g/cm3, and pressures exceeding 100 billion atmospheres. Such conditions exist naturally only in the interiors of the stars and during thermonuclear burn. Demonstration of ignition and thermonuclear burn in the laboratory is a major NIF goal. To date, the NIF laser has demonstrated all pulse shape, beam quality, energy, and other specifications required to meet the ignition challenge. On March 10, 2009, the NIF laser delivered 1.1 MJ of ultraviolet laser energy to target chamber center, approximately 30 times more energy than any previous facility. The ignition program at NIF is the National Ignition Campaign (NIC), a national collaboration for ignition experimentation with participation from General Atomics, LLNL, Los Alamos National Laboratory (LANL), Sandia National Laboratories (SNL), and the University of Rochester Laboratory for Laser Energetics (LLE). The achievement of ignition at NIF will demonstrate the scientific feasibility of ICF and focus worldwide attention on fusion as a viable energy option. A particular energy concept under investigation is the LIFE (Laser Inertial Fusion Energy) scheme. The LIFE engine is inherently safe, minimizes proliferation concerns associated with the nuclear fuel cycle, and can provide a sustainable carbon-free energy generation solution in the 21st century. This talk will describe NIF and its potential as a user facility and an experimental platform for high-energy-density science, NIC, and the LIFE approach for clean, sustainable energy.

  16. SAFIRE: A systems analysis code for ICF (inertial confinement fusion) reactor economics

    SciTech Connect

    McCarville, T.J.; Meier, W.R.; Carson, C.F.; Glasgow, B.B.

    1987-01-12

    The SAFIRE (Systems Analysis for ICF Reactor Economics) code incorporates analytical models for scaling the cost and performance of several inertial confinement fusion reactor concepts for electric power. The code allows us to vary design parameters (e.g., driver energy, chamber pulse rate, net electric power) and evaluate the resulting change in capital cost of power plant and the busbar cost of electricity. The SAFIRE code can be used to identify the most attractive operating space and to identify those design parameters with the greatest leverage for improving the economics of inertial confinement fusion electric power plants.

  17. Achieving competitive excellence in nuclear energy: The threat of proliferation; the challenge of inertial confinement fusion

    SciTech Connect

    Nuckolls, J.H.

    1994-06-01

    Nuclear energy will have an expanding role in meeting the twenty-first-century challenges of population and economic growth, energy demand, and global warming. These great challenges are non-linearly coupled and incompletely understood. In the complex global system, achieving competitive excellence for nuclear energy is a multi-dimensional challenge. The growth of nuclear energy will be driven by its margin of economic advantage, as well as by threats to energy security and by growing evidence of global warming. At the same time, the deployment of nuclear energy will be inhibited by concerns about nuclear weapons proliferation, nuclear waste and nuclear reactor safety. These drivers and inhibitors are coupled: for example, in the foreseeable future, proliferation in the Middle East may undermine energy security and increase demand for nuclear energy. The Department of Energy`s nuclear weapons laboratories are addressing many of these challenges, including nuclear weapons builddown and nonproliferation, nuclear waste storage and burnup, reactor safety and fuel enrichment, global warming, and the long-range development of fusion energy. Today I will focus on two major program areas at the Lawrence Livermore National Laboratory (LLNL): the proliferation of nuclear weapons and the development of inertial confinement fusion (ICF) energy.

  18. Knudsen and inverse Knudsen layer effect on tail ion distribution and fusion reactivity in inertial confinement fusion targets

    NASA Astrophysics Data System (ADS)

    McDevitt, C. J.; Tang, X.-Z.; Guo, Z.; Berk, H. L.

    2014-10-01

    A series of reduced models are used to study the fast ion tail in the vicinity of a transition layer between plasmas at disparate temperatures and densities, which is typical of the gas-pusher interface in inertial confinement fusion targets. Emphasis is placed on utilizing progressively more comprehensive models in order to identify the essential physics for computing the fast ion tail at energies comparable to the Gamow peak. The resulting fast ion tail distribution is subsequently used to compute the fusion reactivity as a function of collisionality and temperature. It is found that while the fast ion distribution can be significantly depleted in the hot spot, leading to a reduction of the fusion reactivity in this region, a surplus of fast ions is present in the neighboring cold region. The presence of this fast ion surplus in the neighboring cold region is shown to lead to a partial recovery of the fusion yield lost in the hot spot.

  19. Spherical fusion plasma-confinement field of Surmac type

    SciTech Connect

    Wipf, S.L.

    1981-01-01

    The concept of a Surmac confinement field that can be completely closed is presented. The internal conductor is magnetically suspended inside large corrugations of a superconducting spherical shell structure that carries the return current. Presently available superconductor technology using superfluid helium cooling allows fields above 1.5T throughout the wall region. Such a Surmac has potential for the study of advanced fuel cycles.

  20. Fusion programs in applied plasma physics

    SciTech Connect

    Not Available

    1992-02-01

    The objectives of the theoretical science program are: To support the interpretation of present experiments and predict the outcome of future planned experiments; to improve on existing models and codes and validate against experimental results; and to conduct theoretical physics development of advanced concepts with applications for DIII-D and future devices. Major accomplishments in FY91 include the corroboration between theory and experiment on MHD behavior in the second stable regime of operation on DIII-D, and the frequency and mode structure of toroidal Alfven eigenmodes in high beta, shaped plasmas. We have made significant advances in the development of the gyro-Landau fluid approach to turbulence simulation which more accurately models kinetic drive and damping mechanisms. Several theoretical models to explain the bifurcation phenomenon in L- to H-mode transition were proposed providing the theoretical basis for future experimental verification. The capabilities of new rf codes have been upgraded in response to the expanding needs of the rf experiments. Codes are being employed to plan for a fully non-inductive current drive experiment in a high beta, enhanced confinement regime. GA's experimental effort in Applied Physics encompasses two advanced diagnostics essential for the operation of future fusion experiments: Alpha particle diagnostic, and current and density profile diagnostics. This paper discusses research in all these topics.

  1. Deflagration-to-detonation transition in inertial-confinement-fusion baseline targets.

    PubMed

    Gauthier, P; Chaland, F; Masse, L

    2004-11-01

    By means of highly resolved one-dimensional hydrodynamics simulations, we provide an understanding of the burn process in inertial-confinement-fusion baseline targets. The cornerstone of the phenomenology of propagating burn in such laser-driven capsules is shown to be the transition from a slow unsteady reaction-diffusion regime of thermonuclear combustion (some sort of deflagration) to a fast detonative one. Remarkably, detonation initiation follows the slowing down of a shockless supersonic reaction wave driven by energy redeposition from the fusion products themselves. Such a route to detonation is specific to fusion plasmas. PMID:15600681

  2. Deflagration-to-detonation transition in inertial-confinement-fusion baseline targets

    SciTech Connect

    Gauthier, P.; Chaland, F.; Masse, L.

    2004-11-01

    By means of highly resolved one-dimensional hydrodynamics simulations, we provide an understanding of the burn process in inertial-confinement-fusion baseline targets. The cornerstone of the phenomenology of propagating burn in such laser-driven capsules is shown to be the transition from a slow unsteady reaction-diffusion regime of thermonuclear combustion (some sort of deflagration) to a fast detonative one. Remarkably, detonation initiation follows the slowing down of a shockless supersonic reaction wave driven by energy redeposition from the fusion products themselves. Such a route to detonation is specific to fusion plasmas.

  3. Alpha Heating and Burning Plasmas in Inertial Confinement Fusion

    NASA Astrophysics Data System (ADS)

    Betti, R.; Christopherson, A. R.; Spears, B. K.; Nora, R.; Bose, A.; Howard, J.; Woo, K. M.; Edwards, M. J.; Sanz, J.

    2015-06-01

    Estimating the level of alpha heating and determining the onset of the burning plasma regime is essential to finding the path towards thermonuclear ignition. In a burning plasma, the alpha heating exceeds the external input energy to the plasma. Using a simple model of the implosion, it is shown that a general relation can be derived, connecting the burning plasma regime to the yield enhancement due to alpha heating and to experimentally measurable parameters such as the Lawson ignition parameter. A general alpha-heating curve is found, independent of the target and suitable to assess the performance of all laser fusion experiments whether direct or indirect drive. The onset of the burning plasma regime inside the hot spot of current implosions on the National Ignition Facility requires a fusion yield of about 50 kJ.

  4. Alpha Heating and Burning Plasmas in Inertial Confinement Fusion.

    PubMed

    Betti, R; Christopherson, A R; Spears, B K; Nora, R; Bose, A; Howard, J; Woo, K M; Edwards, M J; Sanz, J

    2015-06-26

    Estimating the level of alpha heating and determining the onset of the burning plasma regime is essential to finding the path towards thermonuclear ignition. In a burning plasma, the alpha heating exceeds the external input energy to the plasma. Using a simple model of the implosion, it is shown that a general relation can be derived, connecting the burning plasma regime to the yield enhancement due to alpha heating and to experimentally measurable parameters such as the Lawson ignition parameter. A general alpha-heating curve is found, independent of the target and suitable to assess the performance of all laser fusion experiments whether direct or indirect drive. The onset of the burning plasma regime inside the hot spot of current implosions on the National Ignition Facility requires a fusion yield of about 50 kJ. PMID:26197131

  5. Alpha heating and burning plasmas in inertial confinement fusion

    SciTech Connect

    Betti, R.; Christopherson, A. R.; Spears, B. K.; Nora, R.; Bose, A.; Howard, J.; Woo, K. M.; Edwards, M. J.; Sanz, J.

    2015-06-01

    Estimating the level of alpha heating and determining the onset of the burning plasma regime is essential to finding the path towards thermonuclear ignition. In a burning plasma, the alpha heating exceeds the external input energy to the plasma. Using a simple model of the implosion, it is shown that a general relation can be derived, connecting the burning plasma regime to the yield enhancement due to alpha heating and to experimentally measurable parameters such as the Lawson ignition parameter. A general alpha-heating curve is found, independent of the target and suitable to assess the performance of all laser fusion experiments whether direct or indirect drive. The onset of the burning plasma regime inside the hot spot of current implosions on the National Ignition Facility requires a fusion yield of about 50 kJ.

  6. Pre-Amplifier Module for Laser Inertial Confinement Fusion

    SciTech Connect

    Heebner, J E; Bowers, M W

    2008-02-06

    The Pre-Amplifier Modules (PAMs) are the heart of the National Ignition Facility (NIF), providing most of the energy gain for the most energetic laser in the world. Upon completion, NIF will be the only laboratory in which scientists can examine the fusion processes that occur inside stars, supernovae, and exploding nuclear weapons and that may someday serve as a virtually inexhaustible energy source for electricity. Consider that in a fusion power plant 50 cups of water could provide the energy comparable to 2 tons of coal. Of paramount importance for achieving laser-driven fusion ignition with the least energy input is the synchronous and symmetric compression of the target fuel--a condition known as laser power balance. NIF's 48 PAMs thus must provide energy gain in an exquisitely stable and consistent manner. While building one module that meets performance requirements is challenging enough, our design has already enabled the construction and fielding of 48 PAMs that are stable, uniform, and interchangeable. PAM systems are being tested at the University of Rochester's Laboratory for Laser Energetics, and the Atomic Weapons Enterprise of Great Britain has purchased the PAM power system.

  7. Confined space entry program for the Westinghouse Hanford Company

    SciTech Connect

    Cornell, T.M.

    1993-11-01

    To comply with anticipated OSHA regulatory requirements concerning Permit-Required Confined Spaces, Westinghouse Hanford Company (WHC) created a Confined Spaces Task Team. The primary focus of the task team was to prepare a formal Confined Space Entry (CSE) Program that would ensure full compliance with the anticipated OSHA requirements. A comprehensive training plan was also prepared and submitted for approval as soon as the new CSE Program was approved and released for implementation. On January 14, 1993, OSHA released their final ruling which contained several further changes, requiring the WHC Confined Space Entry Program and Training Plan to be revised. The revised training manual and lessons learned in establishing a Confined Space Entry Program are presented.

  8. Inertially confined fusion plasmas dominated by alpha-particle self-heating

    NASA Astrophysics Data System (ADS)

    Hurricane, O. A.; Callahan, D. A.; Casey, D. T.; Dewald, E. L.; Dittrich, T. R.; Döppner, T.; Haan, S.; Hinkel, D. E.; Berzak Hopkins, L. F.; Jones, O.; Kritcher, A. L.; Le Pape, S.; Ma, T.; Macphee, A. G.; Milovich, J. L.; Moody, J.; Pak, A.; Park, H.-S.; Patel, P. K.; Ralph, J. E.; Robey, H. F.; Ross, J. S.; Salmonson, J. D.; Spears, B. K.; Springer, P. T.; Tommasini, R.; Albert, F.; Benedetti, L. R.; Bionta, R.; Bond, E.; Bradley, D. K.; Caggiano, J.; Celliers, P. M.; Cerjan, C.; Church, J. A.; Dylla-Spears, R.; Edgell, D.; Edwards, M. J.; Fittinghoff, D.; Barrios Garcia, M. A.; Hamza, A.; Hatarik, R.; Herrmann, H.; Hohenberger, M.; Hoover, D.; Kline, J. L.; Kyrala, G.; Kozioziemski, B.; Grim, G.; Field, J. E.; Frenje, J.; Izumi, N.; Gatu Johnson, M.; Khan, S. F.; Knauer, J.; Kohut, T.; Landen, O.; Merrill, F.; Michel, P.; Moore, A.; Nagel, S. R.; Nikroo, A.; Parham, T.; Rygg, R. R.; Sayre, D.; Schneider, M.; Shaughnessy, D.; Strozzi, D.; Town, R. P. J.; Turnbull, D.; Volegov, P.; Wan, A.; Widmann, K.; Wilde, C.; Yeamans, C.

    2016-08-01

    Alpha-particle self-heating, the process of deuterium-tritium fusion reaction products depositing their kinetic energy locally within a fusion reaction region and thus increasing the temperature in the reacting region, is essential for achieving ignition in a fusion system. Here, we report new inertial confinement fusion experiments where the alpha-particle heating of the plasma is dominant with the fusion yield produced exceeding the fusion yield from the work done on the fuel (pressure times volume change) by a factor of two or more. These experiments have achieved the highest yield (26 +/- 0.5 kJ) and stagnation pressures (≍220 +/- 40 Gbar) of any facility-based inertial confinement fusion experiments, although they are still short of the pressures required for ignition on the National Ignition Facility (~300-400 Gbar). These experiments put us in a new part of parameter space that has not been extensively studied so far because it lies between the no-alpha-particle-deposition regime and ignition.

  9. Heavy ion beam propagation through a gas-filled chamber for inertial confinement fusion

    SciTech Connect

    Barboza, N.O.

    1996-10-01

    The work presented here evaluates the dynamics of a beam of heavy ions propagating through a chamber filled with gas. The motivation for this research stems from the possibility of using heavy ion beams as a driver in inertial confinement fusion reactors for the purpose of generating electricity. Such a study is important in determining the constraints on the beam which limit its focus to the small radius necessary for the ignition of thermonuclear microexplosions which are the source of fusion energy. Nuclear fusion is the process of combining light nuclei to form heavier ones. One possible fusion reaction combines two isotopes of hydrogen, deuterium and tritium, to form an alpha particle and a neutron, with an accompanying release of {approximately}17.6 MeV of energy. Generating electricity from fusion requires that we create such reactions in an efficient and controlled fashion, and harness the resulting energy. In the inertial confinement fusion (ICF) approach to energy production, a small spherical target, a few millimeters in radius, of deuterium and tritium fuel is compressed so that the density and temperature of the fuel are high enough, {approximately}200 g/cm{sup 3} and {approximately}20 keV, that a substantial number of fusion reactions occur; the pellet microexplosion typically releases {approximately}350 MJ of energy in optimized power plant scenarios.

  10. Purdue Contribution of Fusion Simulation Program

    SciTech Connect

    Jeffrey Brooks

    2011-09-30

    The overall science goal of the FSP is to develop predictive simulation capability for magnetically confined fusion plasmas at an unprecedented level of integration and fidelity. This will directly support and enable effective U.S. participation in research related to the International Thermonuclear Experimental Reactor (ITER) and the overall mission of delivering practical fusion energy. The FSP will address a rich set of scientific issues together with experimental programs, producing validated integrated physics results. This is very well aligned with the mission of the ITER Organization to coordinate with its members the integrated modeling and control of fusion plasmas, including benchmarking and validation activities. [1]. Initial FSP research will focus on two critical areas: 1) the plasma edge and 2) whole device modeling including disruption avoidance. The first of these problems involves the narrow plasma boundary layer and its complex interactions with the plasma core and the surrounding material wall. The second requires development of a computationally tractable, but comprehensive model that describes all equilibrium and dynamic processes at a sufficient level of detail to provide useful prediction of the temporal evolution of fusion plasma experiments. The initial driver for the whole device model (WDM) will be prediction and avoidance of discharge-terminating disruptions, especially at high performance, which are a critical impediment to successful operation of machines like ITER. If disruptions prove unable to be avoided, their associated dynamics and effects will be addressed in the next phase of the FSP. The FSP plan targets the needed modeling capabilities by developing Integrated Science Applications (ISAs) specific to their needs. The Pedestal-Boundary model will include boundary magnetic topology, cross-field transport of multi-species plasmas, parallel plasma transport, neutral transport, atomic physics and interactions with the plasma wall

  11. Ion distribution in the hot spot of an inertial confinement fusion plasma

    NASA Astrophysics Data System (ADS)

    Tang, Xianzhu; Guo, Zehua; Berk, Herb

    2012-10-01

    Maximizing the fusion gain of inertial confinement fusion (ICF) for inertial fusion energy (IFE) applications leads to the standard scenario of central hot spot ignition followed by propagating burn wave through the cold/dense assembled fuel. The fact that the hot spot is surrounded by cold but dense fuel layer introduces subtle plasma physics which requires a kinetic description. Here we perform Fokker-Planck calculations and kinetic PIC simulations for an ICF plasma initially in pressure balance but having large temperature gradient over a narrow transition layer. The loss of the fast ion tail from the hot spot, which is important for fusion reactivity, is quantified by Fokker-Planck models. The role of electron energy transport and the ambipolar electric field is investigated via kinetic simulations and the fluid moment models. The net effect on both hot spot ion temperature and the ion tail distribution, and hence the fusion reactivity, is elucidated.

  12. A measurable Lawson criterion and hydro-equivalent curves for inertial confinement fusion

    SciTech Connect

    Zhou, C. D.; Betti, R.

    2008-01-01

    This article demonstrates how the ignition condition (Lawson criterion) for inertial confinement fusion (ICF) can be cast in a form depending on the only two parameters of the compressed fuel assembly that can be measured with methods already in existence: the hot spot ion temperature and the total areal density.

  13. Engineering design of the Nova Laser Facility for inertial-confinement fusion

    SciTech Connect

    Simmons, W W; Godwin, R O; Hurley, C A; Wallerstein, E. P.; Whitham, K.; Murray, J. E.; Bliss, E. S.; Ozarski, R. G.; Summers, M. A.; Rienecker, F.; Gritton, D. G.; Holloway, F. W.; Suski, G. J.; Severyn, J. R.

    1982-01-25

    The design of the Nova Laser Facility for inertial confinement fusion experiments at Lawrence Livermore National Laboratory is presented from an engineering perspective. Emphasis is placed upon design-to-performance requirements as they impact the various subsystems that comprise this complex experimental facility.

  14. Program status 1. quarter -- FY 1989: Confinement systems programs

    SciTech Connect

    1989-01-20

    Brief summaries are given for DIII-D Research Operations covering the following areas: beta and stability; confinement; boundary physics; electron cyclotron heating; ion Bernstein wave heating; current drive; tokamak operations; neutral beam operations; ECH operations; ICH operations; computer data systems; program development; and hardware development. The progress summaries on the International Cooperation task are given for the Tora Supra, HIDEX -- Nagoya Tokamak Experiment, ASDEX, JET, JFT-2M, CHS, and JT-60. Finally a brief summary of progress on the CIT physics task is given.

  15. Magnetic-compression/magnetized-target fusion (MAGO/MTF): A marriage of inertial and magnetic confinement

    SciTech Connect

    Lindemuth, I.R.; Ekdahl, C.A.; Kirkpatrick, R.C.

    1996-12-31

    Intermediate between magnetic confinement (MFE) and inertial confinement (ICF) in time and density scales is an area of research now known in the US as magnetized target fusion (MTF) and in Russian as MAGO (MAGnitnoye Obzhatiye--magnetic compression). MAGO/MTF uses a magnetic field and preheated, wall-confined plasma fusion fuel within an implodable fusion target. The magnetic field suppresses thermal conduction losses in the fuel during the target implosion and hydrodynamic compression heating process. In contrast to direct, hydrodynamic compression of initially ambient-temperature fuel (i.e., ICF), MAGO/MTF involves two steps: (a) formation of a warm (e.g., 100 eV or higher), magnetized (e.g., 100 kG) plasma within a fusion target prior to implosion; (b) subsequent quasi-adiabatic compression by an imploding pusher, of which a magnetically driven imploding liner is one example. In this paper, the authors present ongoing activities and potential future activities in this relatively unexplored area of controlled thermonuclear fusion.

  16. Simulating the magnetized liner inertial fusion plasma confinement with smaller-scale experiments

    SciTech Connect

    Ryutov, D. D.; Cuneo, M. E.; Herrmann, M. C.; Sinars, D. B.; Slutz, S. A.

    2012-06-15

    The recently proposed magnetized liner inertial fusion approach to a Z-pinch driven fusion [Slutz et al., Phys. Plasmas 17, 056303 (2010)] is based on the use of an axial magnetic field to provide plasma thermal insulation from the walls of the imploding liner. The characteristic plasma transport regimes in the proposed approach cover parameter domains that have not been studied yet in either magnetic confinement or inertial confinement experiments. In this article, an analysis is presented of the scalability of the key physical processes that determine the plasma confinement. The dimensionless scaling parameters are identified and conclusion is drawn that the plasma behavior in scaled-down experiments can correctly represent the full-scale plasma, provided these parameters are approximately the same in two systems. This observation is important in that smaller-scale experiments typically have better diagnostic access and more experiments per year are possible.

  17. Measurements of classical fast ion confinement with fusion product diagnostics

    NASA Astrophysics Data System (ADS)

    Magee, Richard; Clary, Ryan; Korepanov, Sergey; Smirnov, Artem; Garate, Eusebio; Allfrey, Ian; Valentine, Travis; the TAE Team

    2014-10-01

    Neutral beam injected fast ions play a critical role in the C-2 field reversed configuration plasma, helping to sustain magnetic flux against resistive decay and heating the plasma via Coulomb collisions. The fast ions are well confined; due to the relatively low magnetic field strength the fast ions have large, machine-size orbits that permit them to average over otherwise deleterious fluctuations. These same orbits however, have large radial excursions that result in greater interaction of fast ions with edge neutrals and a greater potential for charge exchange losses. In this presentation, the fast ion slowing down time is determined from the decay in neutron flux following beam termination. It is found that the slowing down scaling is close to classical (i.e., τ ~Te3/2/ne) and that charge exchange losses are only significant for ions with 1.5× the nominal injection energy. We will also present initial data from a newly installed proton detector, which complements the temporal resolution of the neutron detector with spatial resolution. The detector will be used to diagnose the axial profile of confined fast ions.

  18. Role of hydrodynamic instability growth in hot-spot mass gain and fusion performance of inertial confinement fusion implosions

    SciTech Connect

    Srinivasan, Bhuvana; Tang, Xian-Zhu

    2014-10-15

    In an inertial confinement fusion target, energy loss due to thermal conduction from the hot-spot will inevitably ablate fuel ice into the hot-spot, resulting in a more massive but cooler hot-spot, which negatively impacts fusion yield. Hydrodynamic mix due to Rayleigh-Taylor instability at the gas-ice interface can aggravate the problem via an increased gas-ice interfacial area across which energy transfer from the hot-spot and ice can be enhanced. Here, this mix-enhanced transport effect on hot-spot fusion-performance degradation is quantified using contrasting 1D and 2D hydrodynamic simulations, and its dependence on effective acceleration, Atwood number, and ablation speed is identified.

  19. High convergence, indirect drive inertial confinement fusion experiments at Nova

    SciTech Connect

    Lerche, R.A.; Cable, M.D.; Hatchett, S.P.

    1995-06-02

    High convergence, indirect drive implosion experiments have been done at the Nova Laser Facility. The targets were deuterium and deuterium/tritium filled, glass microballoons driven symmetrically by x rays produced in a surrounding uranium hohlraum. Implosions achieved convergence ratios of 24:1 with fuel densities of 19 g/cm{sup 3}; this is equivalent to the range required for the hot spot of ignition scale capsules. The implosions used a shaped drive and were well characterized by a variety of laser and target measurements. The primary measurement was the fuel density using the secondary neutron technique (neutrons from the reaction {sup 2}H({sup 3}H,n){sup 4}He in initially pure deuterium fuel). Laser measurements include power, energy and pointing. Simultaneous measurement of neutron yield, fusion reaction rate, and x-ray images provide additional information about the implosion process. Computer models are in good agreement with measured results.

  20. System and method for generating steady state confining current for a toroidal plasma fusion reactor

    DOEpatents

    Fisch, Nathaniel J.

    1981-01-01

    A system for generating steady state confining current for a toroidal plasma fusion reactor providing steady-state generation of the thermonuclear power. A dense, hot toroidal plasma is initially prepared with a confining magnetic field with toroidal and poloidal components. Continuous wave RF energy is injected into said plasma to establish a spectrum of traveling waves in the plasma, where the traveling waves have momentum components substantially either all parallel, or all anti-parallel to the confining magnetic field. The injected RF energy is phased to couple to said traveling waves with both a phase velocity component and a wave momentum component in the direction of the plasma traveling wave components. The injected RF energy has a predetermined spectrum selected so that said traveling waves couple to plasma electrons having velocities in a predetermined range .DELTA.. The velocities in the range are substantially greater than the thermal electron velocity of the plasma. In addition, the range is sufficiently broad to produce a raised plateau having width .DELTA. in the plasma electron velocity distribution so that the plateau electrons provide steady-state current to generate a poloidal magnetic field component sufficient for confining the plasma. In steady state operation of the fusion reactor, the fusion power density in the plasma exceeds the power dissipated in the plasma.

  1. System and method for generating steady state confining current for a toroidal plasma fusion reactor

    DOEpatents

    Bers, Abraham

    1981-01-01

    A system for generating steady state confining current for a toroidal plasma fusion reactor providing steady-state generation of the thermonuclear power. A dense, hot toroidal plasma is initially prepared with a confining magnetic field with toroidal and poloidal components. Continuous wave RF energy is injected into said plasma to estalish a spectrum of traveling waves in the plasma, where the traveling waves have momentum components substantially either all parallel, or all anti-parallel to the confining magnetic field. The injected RF energy is phased to couple to said traveling waves with both a phase velocity component and a wave momentum component in the direction of the plasma traveling wave components. The injected RF energy has a predetermined spectrum selected so that said traveling waves couple to plasma electrons having velocities in a predetermined range .DELTA.. The velocities in the range are substantially greater than the thermal electron velocity of the plasma. In addition, the range is sufficiently broad to produce a raised plateau having width .DELTA. in the plasma electron velocity distribution so that the plateau electrons provide steady-state current to generate a poloidal magnetic field component sufficient for confining the plasma. In steady state operation of the fusion reactor, the fusion power density in the plasma exceeds the power dissipated inthe plasma.

  2. Heavy ion beam transport in an inertial confinement fusion reactor

    SciTech Connect

    Barboza, N.

    1995-08-01

    A new code, bimc, is under development to determine if a beam of heavy ions can be focused to the necessary spot-size radius of about 2 mm within an inertial confinement reactor chamber where the background gas densities are on the order of 10{sup 14}--10{sup 15} cm{sup {minus}3} Lithium (or equivalent). Beam transport is expected to be strongly affected by stripping and collective plasma phenomena; however, if propagation is possible in this regime, it could lead to simplified reactor designs. The beam is modeled using a 2 1/2 D particle-in-cell (PIC) simulation code coupled with a Monte Carlo (MC) method for analyzing collisions. The MC code follows collisions between the beam ions and neutral background gas atoms that account for the generation of electrons and background gas ions (ionization), and an increase of the charge state of the beam ions (stripping). The PIC code models the complete dynamics of the interaction of the various charged particle species with the self generated electromagnetic fields. Details of the code model and preliminary results are presented.

  3. Computational challenges in magnetic-confinement fusion physics

    NASA Astrophysics Data System (ADS)

    Fasoli, A.; Brunner, S.; Cooper, W. A.; Graves, J. P.; Ricci, P.; Sauter, O.; Villard, L.

    2016-05-01

    Magnetic-fusion plasmas are complex self-organized systems with an extremely wide range of spatial and temporal scales, from the electron-orbit scales (~10-11 s, ~ 10-5 m) to the diffusion time of electrical current through the plasma (~102 s) and the distance along the magnetic field between two solid surfaces in the region that determines the plasma-wall interactions (~100 m). The description of the individual phenomena and of the nonlinear coupling between them involves a hierarchy of models, which, when applied to realistic configurations, require the most advanced numerical techniques and algorithms and the use of state-of-the-art high-performance computers. The common thread of such models resides in the fact that the plasma components are at the same time sources of electromagnetic fields, via the charge and current densities that they generate, and subject to the action of electromagnetic fields. This leads to a wide variety of plasma modes of oscillations that resonate with the particle or fluid motion and makes the plasma dynamics much richer than that of conventional, neutral fluids.

  4. Inertial confinement fusion target component fabrication and technology development support. Annual report, October 1, 1994--September 30, 1995

    SciTech Connect

    Hoppe, M.

    1996-05-01

    On December 30, 1990, the US Department of Energy entered into a contract with General Atomics (GA) to be the Inertial Confinement Fusion (ICF) Target Component Fabrication and Technology Development Support contractor. This report documents the technical activities of the period October 1, 1994 through September 30, 1995. During this period, GA was assigned 15 tasks in support of the Inertial Confinement Fusion program and its laboratories. A portion of the effort on these tasks included providing direct ``Onsite Support`` at Lawrence Livermore National Laboratory (LLNL), Los Alamos National Laboratory (LANL), and Sandia National Laboratory Albuquerque (SNLA). The ICF program is anticipating experiments at the National Ignition Facility (NIF) and the OMEGA Upgrade. Both facilities will require capsules containing layered D{sub 2} or deuterium-tritium (D-T) fuel. The authors are part of the National Cryogenic Target Program to create and demonstrate viable ways to generate and characterize cryogenic layers. Progress has been made on ways to both create viable layers and to characterize them. They continued engineering, assembly and testing of equipment for a cryogenic target handling system for University of Rochester`s Laboratory for Laser Energetics (UR/LLE) that will fill, transport, layer, and characterize targets filled with cryogenic fuel, and insert these cryogenic targets into the OMEGA Upgrade target chamber for laser implosion experiments. This report summarizes and documents the technical progress made on these tasks.

  5. A Reconsideration of Electrostatically Accelerated and Confined Nuclear Fusion for Space Applications

    NASA Astrophysics Data System (ADS)

    MacLeod, C.; Gow, K. S.

    Most present-day research into Nuclear Fusion concentrates on high-temperature plasmas combined with Inertial or Magnetic Confinement. However, there exists another body of less well-known work based on Electrostatic Acceleration and Confinement. The most thoroughly researched of these devices is known as the Farnsworth Fusor. This paper reviews the technique and then argues that, with development, similar technologies would be particularly suited to space-borne applications, due to their safety, simplicity and light weight. The paper then goes on to suggest several possible directions for new research into such devices which might result in a working machine.

  6. HYLIFE-II inertial confinement fusion reactor design

    SciTech Connect

    Moir, R.W.

    1990-12-14

    The HYLIFE-2 inertial fusion power plant design study uses a liquid fall, in the form of jets to protect the first structural wall from neutron damage, x rays, and blast to provide a 30-y lifetime. HYLIFE-1 used liquid lithium. HYLIFE 2 avoids the fire hazard of lithium by using a molten salt composed of fluorine, lithium, and beryllium (Li{sub 2}BeF{sub 4}) called Flibe. Access for heavy-ion beams is provided. Calculations for assumed heavy-ion beam performance show a nominal gain of 70 at 5 MJ producing 350 MJ, about 5.2 times less yield than the 1.8 GJ from a driver energy of 4.5 MJ with gain of 400 for HYLIFE-1. The nominal 1 GWe of power can be maintained by increasing the repetition rate by a factor of about 5.2, from 1.5 to 8 Hz. A higher repetition rate requires faster re-establishment of the jets after a shot, which can be accomplished in part by decreasing the jet fall height and increasing the jet flow velocity. Multiple chambers may be required. In addition, although not considered for HYLIFE-1, there is undoubtedly liquid splash that must be forcibly cleared because gravity is too slow, especially at high repetition rates. Splash removal can be accomplished by either pulsed or oscillating jet flows. The cost of electricity is estimated to be 0.09 $/kW{center dot}h in constant 1988 dollars, about twice that of future coal and light water reactor nuclear power. The driver beam cost is about one-half the total cost. 15 refs., 9 figs., 3 tabs.

  7. HYLIFE-II inertial confinement: Fusion power plant design

    SciTech Connect

    Moir, R.W.

    1990-12-14

    The HYLIFE-2 inertial fusion power plant design study uses a liquid fall, in the form of jets to protect the first structural wall from neutron damage, x rays, and blast to provide a 30-y lifetime. HYLIFE-1 used liquid lithium. HYLIFE 2 avoids the fire hazard of lithium by using a molten salt composed of fluorine, lithium, and beryllium (Li{sub 2}BeF{sub 4}) called Flibe. Access for heavy-ion beams is provided. Calculations for assumed heavy-ion beam performance show a nominal gain of 70 at 5 MJ producing 350 MJ, about 5.2 times less yield than the 1.8 GJ from a driver energy of 4.5 MJ with gain of 400 for HYLIFE-1. The nominal 1 GWe of power can be maintained by increasing the repetition rate by a factor of about 5.2, from 1.5 to 8 Hz. A higher repetition rate requires faster re-establishment of the jets after a shot, which can be accomplished in part by decreasing the jet fall height and increasing the jet flow velocity. Multiple chambers may be required. In addition, although not considered for HYLIFE-1, there is undoubtedly liquid splash that must be forcibly cleared because gravity is too slow, especially at high repetition rates. Splash removal can be accomplished by either pulsed or oscillating jet flows. The cost of electricity is estimated to be 0.09 $/kW{center dot}h in constant 1988 dollars, about twice that of future coal and light water reactor nuclear power. The driver beam cost is about one-half the total cost. 16 refs., 6 figs., 2 tabs.

  8. Inertial confinement fusion. ICF quarterly report, October 1993--December 1993, Volume 4, Number 1

    SciTech Connect

    Powell, H.T.; Schleich, D.P.; Murphy, P.W.

    1994-05-01

    In the 1990 National Academy of Sciences (NAS) report of its review of the U.S. Inertial Confinement Fusion (ICF) Program, it was recommended that a high priority be placed on completing the Precision Nova Project and its associated experimental campaign. Since fiscal year 1990, the lab has therefore campaigned vigorously on Nova and in its supporting laboratories to develop the Precision Nova capabilities needed to perform the stressful target experiments recommended in the 1990 NAS report. The activities to enable these experiments have been directed at improvements in three areas - the Nova laser, target fabrication capabilities, and target diagnostics. As summarized in the five articles in this report, the Precision Nova improvements have been successfully completed. These improvements have had a positive impact on target performance and on the ability to diagnose the results, as evidenced by the HEP-1 experimental results. The five articles generally concentrate on improvements to the capabilities rather than on the associated target physics experiments. Separate abstracts are included for each paper.

  9. Optical Comb Generation for Streak Camera Calibration for Inertial Confinement Fusion Experiments

    SciTech Connect

    Ronald Justin, Terence Davies, Frans Janson, Bruce Marshall, Perry Bell, Daniel Kalantar, Joseph Kimbrough, Stephen Vernon, Oliver Sweningsen

    2008-09-18

    The National Ignition Facility (NIF) at Lawrence Livermore National Laboratory (LLNL) is coming on-line to support physics experimentation for the U.S. Department of Energy (DOE) programs in Inertial Confinement Fusion (ICF) and Stockpile Stewardship (SS). Optical streak cameras are an integral part of the experimental diagnostics instrumentation at NIF. To accurately reduce streak camera data a highly accurate temporal calibration is required. This article describes a technique for simultaneously generating a precise +/- 2 ps optical marker pulse (fiducial reference) and trains of precisely timed, short-duration optical pulses (so-called “comb” pulse trains) that are suitable for the timing calibrations. These optical pulse generators are used with the LLNL optical streak cameras. They are small, portable light sources that, in the comb mode, produce a series of temporally short, uniformly spaced optical pulses, using a laser diode source. Comb generators have been produced with pulse-train repetition rates up to 10 GHz at 780 nm, and somewhat lower frequencies at 664 nm. Individual pulses can be as short as 25-ps FWHM. Signal output is via a fiber-optic connector on the front panel of the generator box. The optical signal is transported from comb generator to streak camera through multi-mode, graded-index optical fiber.

  10. Self-Similar Structure and Experimental Signatures of Suprathermal Ion Distribution in Inertial Confinement Fusion Implosions

    NASA Astrophysics Data System (ADS)

    Kagan, Grigory; Svyatskiy, D.; Rinderknecht, H. G.; Rosenberg, M. J.; Zylstra, A. B.; Huang, C.-K.; McDevitt, C. J.

    2015-09-01

    The distribution function of suprathermal ions is found to be self-similar under conditions relevant to inertial confinement fusion hot spots. By utilizing this feature, interference between the hydrodynamic instabilities and kinetic effects is for the first time assessed quantitatively to find that the instabilities substantially aggravate the fusion reactivity reduction. The ion tail depletion is also shown to lower the experimentally inferred ion temperature, a novel kinetic effect that may explain the discrepancy between the exploding pusher experiments and rad-hydro simulations and contribute to the observation that temperature inferred from DD reaction products is lower than from DT at the National Ignition Facility.

  11. Primary heat transfer loop design for the Cascade inertial confinement fusion reactor

    SciTech Connect

    Murray, K.A.; McDowell, M.W.

    1984-05-01

    This study investigates a heat exchanger and balance of plant design to accompany the Cascade inertial confinement fusion reaction chamber concept. The concept uses solid Li/sub 2/O or other lithium-ceramic granules, held to the wall of a rotating reaction chamber by centrifugal action, as a tritium breeding blanket and first wall protection. The Li/sub 2/O granules enter the chamber at 800 K and exit at 1200 K after absorbing the thermal energy produced by the fusion process.

  12. Fusion energy in an inertial electrostatic confinement device using a magnetically shielded grid

    SciTech Connect

    Hedditch, John Bowden-Reid, Richard Khachan, Joe

    2015-10-15

    Theory for a gridded inertial electrostatic confinement (IEC) fusion system is presented, which shows a net energy gain is possible if the grid is magnetically shielded from ion impact. A simplified grid geometry is studied, consisting of two negatively biased coaxial current-carrying rings, oriented such that their opposing magnetic fields produce a spindle cusp. Our analysis indicates that better than break-even performance is possible even in a deuterium-deuterium system at bench-top scales. The proposed device has the unusual property that it can avoid both the cusp losses of traditional magnetic fusion systems and the grid losses of traditional IEC configurations.

  13. Self-Similar Structure and Experimental Signatures of Suprathermal Ion Distribution in Inertial Confinement Fusion Implosions.

    PubMed

    Kagan, Grigory; Svyatskiy, D; Rinderknecht, H G; Rosenberg, M J; Zylstra, A B; Huang, C-K; McDevitt, C J

    2015-09-01

    The distribution function of suprathermal ions is found to be self-similar under conditions relevant to inertial confinement fusion hot spots. By utilizing this feature, interference between the hydrodynamic instabilities and kinetic effects is for the first time assessed quantitatively to find that the instabilities substantially aggravate the fusion reactivity reduction. The ion tail depletion is also shown to lower the experimentally inferred ion temperature, a novel kinetic effect that may explain the discrepancy between the exploding pusher experiments and rad-hydro simulations and contribute to the observation that temperature inferred from DD reaction products is lower than from DT at the National Ignition Facility. PMID:26382682

  14. Demonstration of Radiation Symmetry Control for Inertial Confinement Fusion in Double Z-Pinch Hohlraums

    NASA Astrophysics Data System (ADS)

    Vesey, R. A.; Cuneo, M. E.; Bennett, G. R.; Porter, J. L.; Adams, R. G.; Aragon, R. A.; Rambo, P. K.; Ruggles, L. E.; Simpson, W. W.; Smith, I. C.

    2003-01-01

    Simulations of a double Z-pinch hohlraum, relevant to the high-yield inertial-confinement-fusion concept, predict that through geometry design the time-integrated P2 Legendre mode drive asymmetry can be systematically controlled from positive to negative coefficient values. Studying capsule elonga­tion, recent experiments on Z confirm such control by varying the secondary hohlraum length. Since the experimental trend and optimum length are correctly modeled, confidence is gained in the simu­lation tools; the same tools predict capsule drive uniformity sufficient for high-yield fusion ignition.

  15. Self-similar structure and experimental signatures of suprathermal ion distribution in inertial confinement fusion implosions

    SciTech Connect

    Kagan, Grigory; Svyatskiy, D.; Rinderknecht, H. G.; Rosenberg, M. J.; Zylstra, A. B.; Huang, C. -K.; McDevitt, C. J.

    2015-09-03

    The distribution function of suprathermal ions is found to be self-similar under conditions relevant to inertial confinement fusion hot spots. By utilizing this feature, interference between the hydrodynamic instabilities and kinetic effects is for the first time assessed quantitatively to find that the instabilities substantially aggravate the fusion reactivity reduction. Thus, the ion tail depletion is also shown to lower the experimentally inferred ion temperature, a novel kinetic effect that may explain the discrepancy between the exploding pusher experiments and rad-hydro simulations and contribute to the observation that temperature inferred from DD reaction products is lower than from DT at the National Ignition Facility.

  16. Program status 3. quarter -- FY 1994: Confinement systems programs

    SciTech Connect

    1994-07-19

    Highlights of the DIII-D Research Operations are: began experimental research operations; successfully passed radiative divertor project review; presented papers at PSI, Diagnostics, and EPS meetings and prepared IAEA synopses; new computer speeds up data acquisition; completed installation of FWCD antennas with Faraday shields; and completed report of radiative divertor preliminary design with review committee. Summaries are given for progress in research programs; operations; mechanical engineering; electrical engineering; upgrade project; operations support; and collaborative efforts. Brief summaries are given for progress on the International Cooperation task which include JET, ASDEX, TEXTOR, TORE SUPRA, JAERI, TRINTI, T-10, and ARIES support. The work in support of the development plan for the TPX (Tokamak Physics Experiment) goals and milestones continued. Progress in improving on existing models and codes leading to improved understanding of experiments is given. Highlights from the User Service Center are: 18 gigabytes of disks were purchased for exclusive fusion use; a Hewlett-Packard 9000 Series 800 T500 computer was selected as the fusion complete server; the first VAX was removed from the USC cluster; security vulnerability on HP VUE software was corrected; and a cleanup script was developed for the NERSC Cray system. A list of personnel and their assignments is given for the ITER Design Engineering task.

  17. Index of light ion inertial confinement fusion publications and presentations January 1989 through December 1993

    SciTech Connect

    Sweeney, M.A.

    1995-11-01

    This report lists publications and presentations that are related to inertial confinement fusion and were authored or coauthored by Sandians in the Pulsed Power Sciences Center from 1989 through 1993. The 661 publications and presentations are categorized into the following general topics: (1) reviews, (2) ion sources, (3) ion diodes, (4) plasma opening switches, (5) ion beam transport, (6) targets and deposition physics, (7) advanced driver and pulsed power technology development, (8) diagnostics, and (9) code development. Research in these areas is arranged by topic in chronological order, with the early efforts under each topic presented first. The work is also categorized alphabetically by first author. A list of acronyms, abbreviations, and definitions of use in understanding light ion inertial confinement fusion research is also included.

  18. Development of backlighting sources for a Compton Radiography diagnostic of Inertial Confinement Fusion targets

    SciTech Connect

    Tommasini, R

    2010-04-23

    An important diagnostic tool for inertial confinement fusion is time-resolved imaging of the dense cold fuel surrounding the hot spot. Here we report on the source and diagnostic development of hard x-ray radiography and on the first radiographs of direct drive implosions obtained at photon energies up to about 100keV, where the Compton effect is the dominant contributor to the shell opacity. The radiographs of direct drive, plastic shell implosions obtained at the OMEGA laser facility have a spatial resolution of {approx}10um and a temporal resolution of {approx}10ps. This novel Compton Radiography is an invaluable diagnostic tool for Inertial Confinement Fusion targets, and will be integrated at the National Ignition Facility (NIF).

  19. Effects of large-angle Coulomb collisions on inertial confinement fusion plasmas.

    PubMed

    Turrell, A E; Sherlock, M; Rose, S J

    2014-06-20

    Large-angle Coulomb collisions affect the rates of energy and momentum exchange in a plasma, and it is expected that their effects will be important in many plasmas of current research interest, including in inertial confinement fusion. Their inclusion is a long-standing problem, and the first fully self-consistent method for calculating their effects is presented. This method is applied to "burn" in the hot fuel in inertial confinement fusion capsules and finds that the yield increases due to an increase in the rate of temperature equilibration between electrons and ions which is not predicted by small-angle collision theories. The equilibration rate increases are 50%-100% for number densities of 10(30)  m(-3) and temperatures around 1 keV. PMID:24996093

  20. Inertial Fusion Program. Progress report, January-December 1980

    SciTech Connect

    Not Available

    1982-05-01

    This report summarizes research and development effort in support of the Inertial Confinement Fusion program, including absorption measurements with an integrating sphere, generation of high CO/sub 2/-laser harmonics in the backscattered light from laser plasmas, and the effects of hydrogen target contamination on the hot-electron temperature and transport. The development of new diagnostics is outlined and measurements taken with a proximity-focused x-ray streak camera are presented. High gain in phase conjugation using germanium was demonstrated, data were obtained on retropulse isolation by plasmas generated from metal shutters, damage thresholds for copper mirrors at high fluences were characterized, and phase conjugation in the ultraviolet was demonstrated. Significant progress in the characterization of targets, new techniques in target coating, and important advances in the development of low-density, small-cell-size plastic foam that permit highly accurate machining to any desired shape are presented. The results of various fusion reactor system studies are summarized.

  1. Three-dimensional simulations of the implosion of inertial confinement fusion targets

    SciTech Connect

    Town, R.P.J.; Bell, A.R. )

    1991-09-30

    The viability of inertial confinement fusion depends crucially on implosion symmetry. A spherical three-dimensional hydrocode called PLATO has been developed to model the growth in asymmetries during an implosion. Results are presented in the deceleration phase which show indistinguishable linear growth rates, but greater nonlinear growth of the Rayleigh-Taylor instability than is found in two-dimensional cylindrical simulations. The three-dimensional enhancement of the nonlinear growth is much smaller than that found by Sakagami and Nishihara.

  2. Particle confinement property in the cusp-mirror field of a compact fusion reactor

    NASA Astrophysics Data System (ADS)

    Zhu, Limin; Liu, Haifeng; Wang, Xianqu

    2016-09-01

    The cusp-mirror magnetic structure in a compact fusion reactor (CFR) is investigated to understand the properties of the particle confinement for the first time. Compared with a cascade magnetic mirror device, its advanced performance is shown by means of test particle simulations. Some interesting results are obtained as follows: the adiabatic region and non-adiabatic region are found in the CFR’s magnetic configuration. In the non-adiabatic region, due to the magnetic field-free space existing, the ions are scattered stochastically and are not directly guided into the loss cone, unlike the particles around the fixed magnetic lines in the adiabatic region, which decrease the ion loss fraction. The CFR’s configuration, combining advantages of cusp-magnetic configuration and mirror-magnetic configuration, leads to confine particles longer than cascade magnetic mirror’s. This phenomenon may be relevant to the construction of advanced magnetic-confinement devices.

  3. Efficient Energy Conversion of the 14 MeV Neutrons in DT Inertial Confinement Fusion

    NASA Astrophysics Data System (ADS)

    Winterberg, F.

    2013-02-01

    In DT fusion 80 % of the energy released goes into 14 MeV neutrons, and only the remaining 20 % into charged particles. Unlike the charged particles, the uncharged neutrons cannot be confined by a magnetic field, and for this reason cannot be used for a direct conversion into electric energy. Instead, the neutrons have to be slowed down in some medium, heating this medium to a temperature of less than 103 K, with the heat removed from this medium to drive a turbo-generator. This conversion of nuclear into electric energy has a Carnot efficiency of about 30 %. For the 80 % of the energy released into neutrons, the efficiency is therefore no more than 24 %. While this low conversion efficiency cannot be overcome in magnetic confinement concepts, it can be overcome in inertial confinement concepts, by surrounding the inertial confinement fusion target with a sufficiently thick layer of liquid hydrogen and a thin outer layer of boron, to create a hot plasma fire ball. The hydrogen layer must be chosen just thick and dense enough to be heated by the neutrons to 100,000 K. The thusly generated, fully ionized, and rapidly expanding fire ball can drive a pulsed magnetohydrodynamic generator at an almost 100 % Carnot efficiency, or possibly be used to generate hydrocarbons.

  4. Shock ignition: a new approach to high gain inertial confinement fusion on the national ignition facility.

    PubMed

    Perkins, L J; Betti, R; LaFortune, K N; Williams, W H

    2009-07-24

    Shock ignition, an alternative concept for igniting thermonuclear fuel, is explored as a new approach to high gain, inertial confinement fusion targets for the National Ignition Facility (NIF). Results indicate thermonuclear yields of approximately 120-250 MJ may be possible with laser drive energies of 1-1.6 MJ, while gains of approximately 50 may still be achievable at only approximately 0.2 MJ drive energy. The scaling of NIF energy gain with laser energy is found to be G approximately 126E (MJ);{0.510}. This offers the potential for high-gain targets that may lead to smaller, more economic fusion power reactors and a cheaper fusion energy development path. PMID:19659364

  5. First downscattered neutron images from Inertial Confinement Fusion experiments at the National Ignition Facility

    NASA Astrophysics Data System (ADS)

    Guler, Nevzat; Aragonez, Robert J.; Archuleta, Thomas N.; Batha, Steven H.; Clark, David D.; Clark, Deborah J.; Danly, Chris R.; Day, Robert D.; Fatherley, Valerie E.; Finch, Joshua P.; Gallegos, Robert A.; Garcia, Felix P.; Grim, Gary; Hsu, Albert H.; Jaramillo, Steven A.; Loomis, Eric N.; Mares, Danielle; Martinson, Drew D.; Merrill, Frank E.; Morgan, George L.; Munson, Carter; Murphy, Thomas J.; Oertel, John A.; Polk, Paul J.; Schmidt, Derek W.; Tregillis, Ian L.; Valdez, Adelaida C.; Volegov, Petr L.; Wang, Tai-Sen F.; Wilde, Carl H.; Wilke, Mark D.; Wilson, Douglas C.; Atkinson, Dennis P.; Bower, Dan E.; Drury, Owen B.; Dzenitis, John M.; Felker, Brian; Fittinghoff, David N.; Frank, Matthias; Liddick, Sean N.; Moran, Michael J.; Roberson, George P.; Weiss, Paul; Buckles, Robert A.; Cradick, Jerry R.; Kaufman, Morris I.; Lutz, Steve S.; Malone, Robert M.; Traille, Albert

    2013-11-01

    Inertial Confinement Fusion experiments at the National Ignition Facility (NIF) are designed to understand and test the basic principles of self-sustaining fusion reactions by laser driven compression of deuterium-tritium (DT) filled cryogenic plastic (CH) capsules. The experimental campaign is ongoing to tune the implosions and characterize the burning plasma conditions. Nuclear diagnostics play an important role in measuring the characteristics of these burning plasmas, providing feedback to improve the implosion dynamics. The Neutron Imaging (NI) diagnostic provides information on the distribution of the central fusion reaction region and the surrounding DT fuel by collecting images at two different energy bands for primary (13-15 MeV) and downscattered (10-12 MeV) neutrons. From these distributions, the final shape and size of the compressed capsule can be estimated and the symmetry of the compression can be inferred. The first downscattered neutron images from imploding ICF capsules are shown in this paper.

  6. Visual programming environment for multisensor data fusion

    NASA Astrophysics Data System (ADS)

    Hall, David L.; Kasmala, Gerald

    1996-06-01

    In recent years, numerous multisensor data fusion systems have been developed for a wide variety of applications. Defense related applications include; automatic target recognition systems, identification-friend-foe-neutral, automated situation assessment and threat assessment systems, and systems for smart weapons. Non-defense applications include; robotics, condition-based maintenance, environmental monitoring, and medical diagnostics. For each of these applications, multiple sensor data are combined to achieve inferences which are not generally possible using only a single sensor. Implementation of these data fusion systems often involves a significant amount of effort. In particular, software must be developed for components such as data base access, human computer interfaces and displays, communication software, and data fusion algorithms. While commercial software packages exist to assist development of data bases, communications, and human computer interfaces, there are no general purpose packages available to support the implementation of the data fusion algorithms. This paper describes a visual programming tool developed to assist in rapid prototyping of data fusion systems. This toolkit is modeled after the popular tool, Khoros, used by the image processing community. The tool described here is written in visual C, and provides the capability to rapidly implement and apply data fusion algorithms. An application to condition based maintenance is described.

  7. Fusion Simulation Program Definition. Final report

    SciTech Connect

    Cary, John R.

    2012-09-05

    We have completed our contributions to the Fusion Simulation Program Definition Project. Our contributions were in the overall planning with concentration in the definition of the area of Software Integration and Support. We contributed to the planning of multiple meetings, and we contributed to multiple planning documents.

  8. Robustness of predator-prey models for confinement regime transitions in fusion plasmas

    SciTech Connect

    Zhu, H.; Chapman, S. C.; Dendy, R. O.

    2013-04-15

    Energy transport and confinement in tokamak fusion plasmas is usually determined by the coupled nonlinear interactions of small-scale drift turbulence and larger scale coherent nonlinear structures, such as zonal flows, together with free energy sources such as temperature gradients. Zero-dimensional models, designed to embody plausible physical narratives for these interactions, can help to identify the origin of enhanced energy confinement and of transitions between confinement regimes. A prime zero-dimensional paradigm is predator-prey or Lotka-Volterra. Here, we extend a successful three-variable (temperature gradient; microturbulence level; one class of coherent structure) model in this genre [M. A. Malkov and P. H. Diamond, Phys. Plasmas 16, 012504 (2009)], by adding a fourth variable representing a second class of coherent structure. This requires a fourth coupled nonlinear ordinary differential equation. We investigate the degree of invariance of the phenomenology generated by the model of Malkov and Diamond, given this additional physics. We study and compare the long-time behaviour of the three-equation and four-equation systems, their evolution towards the final state, and their attractive fixed points and limit cycles. We explore the sensitivity of paths to attractors. It is found that, for example, an attractive fixed point of the three-equation system can become a limit cycle of the four-equation system. Addressing these questions which we together refer to as 'robustness' for convenience is particularly important for models which, as here, generate sharp transitions in the values of system variables which may replicate some key features of confinement transitions. Our results help to establish the robustness of the zero-dimensional model approach to capturing observed confinement phenomenology in tokamak fusion plasmas.

  9. Inertial Fusion Program. Progress report, July 1-December 31, 1979

    SciTech Connect

    Skoberne, F.

    1981-10-01

    Progress in the development of high-energy short-pulse CO/sub 2/ laser systems for fusion research is reported. Improvements in the Los Alamos National Laboratory eight-beam Helios system are described. These improvements increased the reliability of the laser and permitted the firing of 290 shots, most of which delivered energies of approximately 8 kJ to the target. Modifications to Gemini are outlined, including the installation of a new target-insertion mechanism. The redirection of the Antares program is discussed in detail, which will achieve a total energy of approximatey 40 kJ with two beams. This redirection will bring Antares on-line almost two years earlier than was possible with the full six-beam system, although at a lower energy. Experiments with isentropically imploded Sirius-B targets are discussed, and x-ray radiation-loss data from gold microballoons are presented, which show that these results are essentially identical with those obtained at glass-laser wavelengths. Significant progress in characterizing laser fusion targets is reported. New processes for fabricating glass miroballoon x-ray diagnostic targets, the application of high-quality metallic coatings, and the deposition of thick plastic coatings are described. Results in the development of x-ray diagnostics are reported, and research in the Los Alamos heavy-ion fusion program is summarized. Results of investigations of phase-conjugation research of gaseous saturable absorbers and of the use of alkali-halide crystals in a new class of saturable absorbers are summarized. New containment-vessel concepts for Inertial Confinement Fusion reactors are discussed, and results of a scoping study of four fusion-fission hybrid concepts are presented.

  10. HYPERFUSE: a hypervelocity inertial confinement system for fusion energy production and fission waste transmutation

    SciTech Connect

    Makowitz, H; Powell, J R; Wiswall, R

    1980-01-01

    Parametric system studies of an inertial confinement fusion (ICF) reactor system to transmute fission products from an LWR economy have been carried out. The ICF reactors would produce net power in addition to transmuting fission products. The particular ICF concept examined is an impact fusion approach termed HYPERFUSE, in which hypervelocity pellets, traveling on the order of 100 to 300 km/sec, collide with each other or a target block in a reactor chamber and initiate a thermonuclear reaction. The DT fusion fuel is contained in a shell of the material to be transmuted, e.g., /sup 137/Cs, /sup 90/Sr, /sup 129/I, /sup 99/Tc, etc. The 14-MeV fusion neutrons released during the pellet burn cause transmutation reactions (e.g., (n,2n), (n,..cap alpha..), (n,..gamma..), etc.) that convert the long-lived fission products (FP's) either to stable products or to species that decay with a short half-life to a stable product. The transmutation parametric studies conclude that the design of the hypervelocity projectiles should emphasize the achievement of high densities in the transmutation regions (greater than the DT fusion fuel density), as well as the DT ignition and burn criterion (rho R=1.0 to 3.0) requirements.

  11. On the Utility of Antiprotons as Drivers for Inertial Confinement Fusion

    SciTech Connect

    Perkins, L J; Orth, C D; Tabak, M

    2003-10-20

    By contrast to the large mass, complexity and recirculating power of conventional drivers for inertial confinement fusion (ICF), antiproton annihilation offers a specific energy of 90MJ/{micro}g and thus a unique form of energy packaging and delivery. In principle, antiproton drivers could provide a profound reduction in system mass for advanced space propulsion by ICF. We examine the physics underlying the use of antiprotons ({bar p}) to drive various classes of high-yield ICF targets by the methods of volumetric ignition, hotspot ignition and fast ignition. The useable fraction of annihilation deposition energy is determined for both {bar p}-driven ablative compression and {bar p}-driven fast ignition, in association with 0-D and 1-D target burn models. Thereby, we deduce scaling laws for the number of injected antiprotons required per capsule, together with timing and focal spot requirements. The kinetic energy of the injected antiproton beam required to penetrate to the desired annihilation point is always small relative to the deposited annihilation energy. We show that heavy metal seeding of the fuel and/or ablator is required to optimize local deposition of annihilation energy and determine that a minimum of {approx}3x10{sup 15} injected antiprotons will be required to achieve high yield (several hundred megajoules) in any target configuration. Target gains - i.e., fusion yields divided by the available p - {bar p} annihilation energy from the injected antiprotons (1.88GeV/{bar p}) - range from {approx}3 for volumetric ignition targets to {approx}600 for fast ignition targets. Antiproton-driven ICF is a speculative concept, and the handling of antiprotons and their required injection precision - temporally and spatially - will present significant technical challenges. The storage and manipulation of low-energy antiprotons, particularly in the form of antihydrogen, is a science in its infancy and a large scale-up of antiproton production over present supply

  12. Performance test of personal RF monitor for area monitoring at magnetic confinement fusion facility.

    PubMed

    Tanaka, Masahiro; Uda, Tatsuhiko; Wang, Jianqing; Fujiwara, Osamu

    2012-02-01

    For safety management at a magnetic confinement fusion-test facility, protection from not only ionising radiation, but also non-ionising radiation such as the leakage of static magnetic and electromagnetic fields is an important issue. Accordingly, the use of a commercially available personal RF monitor for multipoint area monitoring is proposed. In this study, the performance of both fast- and slow-type personal RF monitors was investigated by using a transverse electromagnetic cell system. The range of target frequencies was between 10 and 300 MHz, corresponding to the ion cyclotron range of frequency in a fusion device. The personal RF monitor was found to have good linearity, frequency dependence and isotropic response. However, the time constant for the electric field sensor of the slow-type monitor was much longer than that for the fast-type monitor. Considering the time-varying field at the facility, it is found that the fast-type monitor is suitable for multipoint monitoring at magnetic confinement fusion test facilities. PMID:21441242

  13. Assessment of ion kinetic effects in shock-driven inertial confinement fusion (ICF) implosions using fusion burn imaging

    DOE PAGESBeta

    Rosenberg, M. J.; Séguin, F. H.; Amendt, P. A.; Atzeni, S.; Rinderknecht, H. G.; Hoffman, N. M.; Zylstra, A. B.; Li, C. K.; Sio, H.; Gatu Johnson, M.; et al

    2015-06-02

    The significance and nature of ion kinetic effects in D³He-filled, shock-driven inertial confinement fusion implosions are assessed through measurements of fusion burn profiles. Over this series of experiments, the ratio of ion-ion mean free path to minimum shell radius (the Knudsen number, NK) was varied from 0.3 to 9 in order to probe hydrodynamic-like to strongly kinetic plasma conditions; as the Knudsen number increased, hydrodynamic models increasingly failed to match measured yields, while an empirically-tuned, first-step model of ion kinetic effects better captured the observed yield trends [Rosenberg et al., Phys. Rev. Lett. 112, 185001 (2014)]. Here, spatially resolved measurementsmore » of the fusion burn are used to examine kinetic ion transport effects in greater detail, adding an additional dimension of understanding that goes beyond zero-dimensional integrated quantities to one-dimensional profiles. In agreement with the previous findings, a comparison of measured and simulated burn profiles shows that models including ion transport effects are able to better match the experimental results. In implosions characterized by large Knudsen numbers (NK ~ 3), the fusion burn profiles predicted by hydrodynamics simulations that exclude ion mean free path effects are peaked far from the origin, in stark disagreement with the experimentally observed profiles, which are centrally peaked. In contrast, a hydrodynamics simulation that includes a model of ion diffusion is able to qualitatively match the measured profile shapes. Therefore, ion diffusion or diffusion-like processes are identified as a plausible explanation of the observed trends, though further refinement of the models is needed for a more complete and quantitative understanding of ion kinetic effects.« less

  14. Assessment of ion kinetic effects in shock-driven inertial confinement fusion implosions using fusion burn imaging

    NASA Astrophysics Data System (ADS)

    Rosenberg, M. J.; Séguin, F. H.; Amendt, P. A.; Atzeni, S.; Rinderknecht, H. G.; Hoffman, N. M.; Zylstra, A. B.; Li, C. K.; Sio, H.; Gatu Johnson, M.; Frenje, J. A.; Petrasso, R. D.; Glebov, V. Yu.; Stoeckl, C.; Seka, W.; Marshall, F. J.; Delettrez, J. A.; Sangster, T. C.; Betti, R.; Wilks, S. C.; Pino, J.; Kagan, G.; Molvig, K.; Nikroo, A.

    2015-06-01

    The significance and nature of ion kinetic effects in D3He-filled, shock-driven inertial confinement fusion implosions are assessed through measurements of fusion burn profiles. Over this series of experiments, the ratio of ion-ion mean free path to minimum shell radius (the Knudsen number, NK) was varied from 0.3 to 9 in order to probe hydrodynamic-like to strongly kinetic plasma conditions; as the Knudsen number increased, hydrodynamic models increasingly failed to match measured yields, while an empirically-tuned, first-step model of ion kinetic effects better captured the observed yield trends [Rosenberg et al., Phys. Rev. Lett. 112, 185001 (2014)]. Here, spatially resolved measurements of the fusion burn are used to examine kinetic ion transport effects in greater detail, adding an additional dimension of understanding that goes beyond zero-dimensional integrated quantities to one-dimensional profiles. In agreement with the previous findings, a comparison of measured and simulated burn profiles shows that models including ion transport effects are able to better match the experimental results. In implosions characterized by large Knudsen numbers (NK ˜ 3), the fusion burn profiles predicted by hydrodynamics simulations that exclude ion mean free path effects are peaked far from the origin, in stark disagreement with the experimentally observed profiles, which are centrally peaked. In contrast, a hydrodynamics simulation that includes a model of ion diffusion is able to qualitatively match the measured profile shapes. Therefore, ion diffusion or diffusion-like processes are identified as a plausible explanation of the observed trends, though further refinement of the models is needed for a more complete and quantitative understanding of ion kinetic effects.

  15. Assessment of ion kinetic effects in shock-driven inertial confinement fusion (ICF) implosions using fusion burn imaging

    SciTech Connect

    Rosenberg, M. J.; Séguin, F. H.; Amendt, P. A.; Atzeni, S.; Rinderknecht, H. G.; Hoffman, N. M.; Zylstra, A. B.; Li, C. K.; Sio, H.; Gatu Johnson, M.; Frenje, J. A.; Petrasso, R. D.; Glebov, V. Yu.; Stoeckl, C.; Seka, W.; Marshall, F. J.; Delettrez, J. A.; Sangster, T. C.; Betti, R.; Wilks, S. C.; Pino, J.; Kagan, G.; Molvig, K.; Nikroo, A.

    2015-06-02

    The significance and nature of ion kinetic effects in D³He-filled, shock-driven inertial confinement fusion implosions are assessed through measurements of fusion burn profiles. Over this series of experiments, the ratio of ion-ion mean free path to minimum shell radius (the Knudsen number, NK) was varied from 0.3 to 9 in order to probe hydrodynamic-like to strongly kinetic plasma conditions; as the Knudsen number increased, hydrodynamic models increasingly failed to match measured yields, while an empirically-tuned, first-step model of ion kinetic effects better captured the observed yield trends [Rosenberg et al., Phys. Rev. Lett. 112, 185001 (2014)]. Here, spatially resolved measurements of the fusion burn are used to examine kinetic ion transport effects in greater detail, adding an additional dimension of understanding that goes beyond zero-dimensional integrated quantities to one-dimensional profiles. In agreement with the previous findings, a comparison of measured and simulated burn profiles shows that models including ion transport effects are able to better match the experimental results. In implosions characterized by large Knudsen numbers (NK ~ 3), the fusion burn profiles predicted by hydrodynamics simulations that exclude ion mean free path effects are peaked far from the origin, in stark disagreement with the experimentally observed profiles, which are centrally peaked. In contrast, a hydrodynamics simulation that includes a model of ion diffusion is able to qualitatively match the measured profile shapes. Therefore, ion diffusion or diffusion-like processes are identified as a plausible explanation of the observed trends, though further refinement of the models is needed for a more complete and quantitative understanding of ion kinetic effects.

  16. Inertial Confinement Fusion. Annual report 10/1/98 through 9/30/99

    SciTech Connect

    Gibson, Jane

    1999-12-01

    General Atomics (GA) has served as the Inertial Confinement Fusion (ICF) Target Component Fabrication and Technology Development Support contractor for the U.S. Department of Energy since December 30, 1990. This report documents the technical activities of the period October 1, 1998 through September 30, 1999. During this period, GA and our partner Schafer Corporation were assigned 17 formal tasks in support of the ICF program and its five laboratories. A portion of the effort on these tasks included providing direct ''Onsite Support'' at Lawrence Livermore National Laboratory (LLNL), Los Alamos National Laboratory (LANL), and Sandia National Laboratory (SNL). We fabricated and delivered over 1790 hohlraum mandrels and numerous other micromachined components to LLNL, LANL, and SNL. We produced more than 1380 glass and plastic target capsules over a wide range of sizes and designs (plus over 300 near target-quality capsules) for LLNL, LANL, SNL, and University of Rochester/Laboratory for Laser Energetic (UR/LLE). We also delivered various target foils and films for Naval Research Lab (NRL) and UWLLE in FY99. We fabricated a device to polish NIF-sized beryllium shells and prepared a laboratory for the safe operation of beryllium polishing activities. This report describes these target fabrication activities and the target fabrication and characterization development activities that made the deliveries possible. During FY99, the GA/Schafer portion of the GA/Schafer-UR/LLE-LANL team effort for design, procurement, installation, and testing of the OMEGA Cryogenic Target System (OCTS) that will field cryogenic targets on OMEGA was completed. All components of the OCTS were procured, fabricated, assembled, tested, and shipped to UR/LLE. Only minor documentation tasks remain to be done in FY00. The ICF program is anticipating experiments at the OMEGA laser and the National Ignition Facility (NIF) which will require targets containing cryogenic layered D2 or deuterium

  17. Evidence for Critical Energy for Ion Confinement in Magnetic Fusion Reactors

    NASA Astrophysics Data System (ADS)

    Maglich, Bogdan; Hester, Tim; Scott, Dan; Calsec Collaboration

    2015-03-01

    It is shown here that fusion test reactors could not ignite for half-a-century because trials were conducted at thermonuclear ion energies 10-30 KeV, an order of magnitude lower than critical energy, Ec ~ 200 KeV. At subcritical energies, plasma is destroyed by neutralization of ions via overlooked atomic (non-nuclear) charge transfer collisions with giant cross-section, 109 barns, 100 times greater than that for ionization collisions that counters neutralization. Neutral injection sets limit on ion magnetic confinement time <10-6 s vs. >1 s required for ignition. In contrast, at energies above Ec, ionization prevails; near ~ 1 MeV, stable confinement of 20 s was routinely observed with charged injection. - To render ITER viable, ion energy must be increased to >/ = 1 MeV; neutral radioactive DT fuel replaced with charged, nonradioactive deuterium, giving rise to compact aneutronicreactor with direct conversion into RF power.

  18. Radiochemical determination of Inertial Confinement Fusion capsule compression at the National Ignition Facility.

    PubMed

    Shaughnessy, D A; Moody, K J; Gharibyan, N; Grant, P M; Gostic, J M; Torretto, P C; Wooddy, P T; Bandong, B B; Despotopulos, J D; Cerjan, C J; Hagmann, C A; Caggiano, J A; Yeamans, C B; Bernstein, L A; Schneider, D H G; Henry, E A; Fortner, R J

    2014-06-01

    We describe a radiochemical measurement of the ratio of isotope concentrations produced in a gold hohlraum surrounding an Inertial Confinement Fusion capsule at the National Ignition Facility (NIF). We relate the ratio of the concentrations of (n,γ) and (n,2n) products in the gold hohlraum matrix to the down-scatter of neutrons in the compressed fuel and, consequently, to the fuel's areal density. The observed ratio of the concentrations of (198m+g)Au and (196g)Au is a performance signature of ablator areal density and the fuel assembly confinement time. We identify the measurement of nuclear cross sections of astrophysical importance as a potential application of the neutrons generated at the NIF. PMID:24985820

  19. Geodesic least squares regression for scaling studies in magnetic confinement fusion

    SciTech Connect

    Verdoolaege, Geert

    2015-01-13

    In regression analyses for deriving scaling laws that occur in various scientific disciplines, usually standard regression methods have been applied, of which ordinary least squares (OLS) is the most popular. However, concerns have been raised with respect to several assumptions underlying OLS in its application to scaling laws. We here discuss a new regression method that is robust in the presence of significant uncertainty on both the data and the regression model. The method, which we call geodesic least squares regression (GLS), is based on minimization of the Rao geodesic distance on a probabilistic manifold. We demonstrate the superiority of the method using synthetic data and we present an application to the scaling law for the power threshold for the transition to the high confinement regime in magnetic confinement fusion devices.

  20. Radiochemical determination of Inertial Confinement Fusion capsule compression at the National Ignition Facility

    SciTech Connect

    Shaughnessy, D. A. Moody, K. J.; Gharibyan, N.; Grant, P. M.; Gostic, J. M.; Torretto, P. C.; Wooddy, P. T.; Bandong, B. B.; Cerjan, C. J.; Hagmann, C. A.; Caggiano, J. A.; Yeamans, C. B.; Bernstein, L. A.; Schneider, D. H. G.; Henry, E. A.; Fortner, R. J.; Despotopulos, J. D.

    2014-06-15

    We describe a radiochemical measurement of the ratio of isotope concentrations produced in a gold hohlraum surrounding an Inertial Confinement Fusion capsule at the National Ignition Facility (NIF). We relate the ratio of the concentrations of (n,γ) and (n,2n) products in the gold hohlraum matrix to the down-scatter of neutrons in the compressed fuel and, consequently, to the fuel's areal density. The observed ratio of the concentrations of {sup 198m+g}Au and {sup 196g}Au is a performance signature of ablator areal density and the fuel assembly confinement time. We identify the measurement of nuclear cross sections of astrophysical importance as a potential application of the neutrons generated at the NIF.

  1. Inertial confinement fusion target component fabrication and technology development support: Annual report, October 1, 1995--September 30, 1996

    SciTech Connect

    Hoppe, M.

    1997-02-01

    On December 30, 1990, the U.S. Department of Energy entered into a contract with General Atomics (GA) to be the Inertial Confinement Fusion (ICF) Target Component Fabrication and Technology Development Support contractor. In September 1995 this contract ended and a second contract was issued for us to continue this ICF target support work. This report documents the technical activities of the period October 1, 1995 through September 30, 1996. During this period, GA and our partners WJ Schafer Associates (WJSA) and Soane Technologies, Inc. (STI) were assigned 14 formal tasks in support of the Inertial Confinement Fusion program and its five laboratories. A portion of the effort on these tasks included providing direct {open_quotes}Onsite Support{close_quotes} at Lawrence Livermore National Laboratory (LLNL), Los Alamos National Laboratory (LANL), and Sandia National Laboratory Albuquerque (SNLA). We fabricated and delivered over 800 gold-plated hohlraum mandrels to LLNL, LANL and SNLA. We produced nearly 1,200 glass and plastic target capsules for LLNL, LANL, SNLA and University of Rochester/Laboratory for Laser Energetics (UR/LLE). We also delivered over 100 flat foil targets for Naval Research Lab (NRL) and SNLA in FY96. This report describes these target fabrication activities and the target fabrication and characterization development activities that made the deliveries possible. The ICF program is anticipating experiments at the OMEGA laser and the National Ignition Facility (NIF) which will require capsules containing cryogenic layered D{sub 2} or deuterium-tritium (DT) fuel. We are part of the National Cryogenic Target Program to create and demonstrate viable ways to generate and characterize cryogenic layers. Substantial progress has been made on ways to both create and characterize viable layers. During FY96, significant progress was made in the design of the OMEGA Cryogenic Target System that will field cryogenic targets on OMEGA.

  2. Assessment of the Fusion Energy Sciences Program. Final Report

    SciTech Connect

    2001-05-01

    An assessment of the Office of Fusion Energy Sciences (OFES) program with guidance for future program strategy. The overall objective of this study is to prepare an independent assessment of the scientific quality of the Office of Fusion Energy Sciences program at the Department of Energy. The Fusion Science Assessment Committee (FuSAC) has been appointed to conduct this study.

  3. Experimental signatures of suprathermal ion distribution in inertial confinement fusion implosions

    NASA Astrophysics Data System (ADS)

    Kagan, Grigory; Svyatskiy, Daniil; Rinderknecht, Hans; Rosenberg, Michael; Zylstra, Alex; Huang, Cheng-Kun; McDevitt, Christopher

    2015-11-01

    The distribution function of suprathermal ions is found to be self-similar under conditions relevant to inertial confinement fusion hot-spots. By utilizing this feature, interference between the hydro-instabilities and kinetic effects is for the first time assessed quantitatively to find that the instabilities substantially aggravate the fusion reactivity reduction. The ion tail depletion is also shown to lower the experimentally inferred ion temperature, a novel kinetic effect that may explain the discrepancy between the exploding pusher experiments and rad-hydro simulations and contribute to the observation that temperature inferred from DD reaction products is lower than from DT at National Ignition Facility. This work is performed under the auspices of the U.S. Dept. of Energy by the Los Alamos National Security, LLC, Los Alamos National Laboratory under Contract No. DE-AC52-06NA25396.

  4. Self-similar structure and experimental signatures of suprathermal ion distribution in inertial confinement fusion implosions

    DOE PAGESBeta

    Kagan, Grigory; Svyatskiy, D.; Rinderknecht, H. G.; Rosenberg, M. J.; Zylstra, A. B.; Huang, C. -K.; McDevitt, C. J.

    2015-09-03

    The distribution function of suprathermal ions is found to be self-similar under conditions relevant to inertial confinement fusion hot spots. By utilizing this feature, interference between the hydrodynamic instabilities and kinetic effects is for the first time assessed quantitatively to find that the instabilities substantially aggravate the fusion reactivity reduction. Thus, the ion tail depletion is also shown to lower the experimentally inferred ion temperature, a novel kinetic effect that may explain the discrepancy between the exploding pusher experiments and rad-hydro simulations and contribute to the observation that temperature inferred from DD reaction products is lower than from DT atmore » the National Ignition Facility.« less

  5. Progress in Direct-Drive Inertial Confinement Fusion Research at the Laboratory for Laser Energetics

    SciTech Connect

    McCrory, R.L.; Meyerhofer, D.D.; Loucks, S.J.; Skupsky, S.; Betti, R.; Boehly, T.R.; Collins, T.J.B.; Craxton, R.S.; Delettrez, J.A.; Edgell, D.H.; Epstein, R.; Fletcher, K.A.; Freeman, C.; Frenje, J.A.; Glebov, V.Yu.; Goncharov, V.N.; Harding, D.R.; Igumenshchev, I.V.; Keck, R.L.; Kilkenny, J.D.; Knauer, J.P.; Li, C.K.; Marciante, J.; Marozas, J.a.; Marshall, F.J.; Maximov, A.V.; McKenty, P.W.; Morse, S.F.B.; Myatt, J.; Padalino, S.; Petrasso, R.D.; Radha, P.B.; Regan, S.P.; Sangster, T.C.; Seguin, F.H.; Seka, W.; Smalyuk, V.A.; Soures, J.M.; Stoeckl, C.; Yaakobi, B.; Zuegel, J.D.

    2006-06-28

    Direct-drive inertial confinement fusion (ICF) is expected to demonstrate high gain on the National Ignition Facility (NIF) in the next decade and is a leading candidate for inertial fusion energy production. The NIF will initially be configured for x-ray drive and with no beams placed at the target equator to provide a symmetric irradiation of a direct-drive capsule. LLE is developing the “polar-direct-drive” (PDD) approach that repoints beams toward the target equator. Initial 2-D simulations have shown ignition. A unique “Saturn-like” plastic ring around the equator refracts the laser light incident near the equator toward the target, improving the drive uniformity.

  6. Manufactured solutions for the three-dimensional Euler equations with relevance to Inertial Confinement Fusion

    SciTech Connect

    Waltz, J.; Canfield, T.R.; Morgan, N.R.; Risinger, L.D.; Wohlbier, J.G.

    2014-06-15

    We present a set of manufactured solutions for the three-dimensional (3D) Euler equations. The purpose of these solutions is to allow for code verification against true 3D flows with physical relevance, as opposed to 3D simulations of lower-dimensional problems or manufactured solutions that lack physical relevance. Of particular interest are solutions with relevance to Inertial Confinement Fusion (ICF) capsules. While ICF capsules are designed for spherical symmetry, they are hypothesized to become highly 3D at late time due to phenomena such as Rayleigh–Taylor instability, drive asymmetry, and vortex decay. ICF capsules also involve highly nonlinear coupling between the fluid dynamics and other physics, such as radiation transport and thermonuclear fusion. The manufactured solutions we present are specifically designed to test the terms and couplings in the Euler equations that are relevant to these phenomena. Example numerical results generated with a 3D Finite Element hydrodynamics code are presented, including mesh convergence studies.

  7. Demonstration of Ignition Radiation Temperatures in Indirect-Drive Inertial Confinement Fusion Hohlraums

    SciTech Connect

    Glenzer, S. H.; MacGowan, B. J.; Meezan, N. B.; Adams, P. A.; Alfonso, J. B.; Alger, E. T.; Alherz, Z.; Alvarez, L. F.; Alvarez, S. S.; Amick, P. V.; Andersson, K. S.; Andrews, S. D.; Antonini, G. J.; Arnold, P. A.; Atkinson, D. P.; Auyang, L.; Azevedo, S. G.; Balaoing, B. N. M.; Baltz, J. A.; Barbosa, F.

    2011-02-25

    We demonstrate the hohlraum radiation temperature and symmetry required for ignition-scale inertial confinement fusion capsule implosions. Cryogenic gas-filled hohlraums with 2.2 mm-diameter capsules are heated with unprecedented laser energies of 1.2 MJ delivered by 192 ultraviolet laser beams on the National Ignition Facility. Laser backscatter measurements show that these hohlraums absorb 87% to 91% of the incident laser power resulting in peak radiation temperatures of T{sub RAD}=300 eV and a symmetric implosion to a 100 {mu}m diameter hot core.

  8. High temperatures in inertial confinement fusion radiation cavities heated with 0. 35 [mu]m light

    SciTech Connect

    Kauffman, R.L.; Suter, L.J.; Darrow, C.B.; Kilkenny, J.D.; Kornblum, H.N.; Montgomery, D.S.; Phillion, D.W.; Rosen, M.D.; Theissen, A.R.; Wallace, R.J.; Ze, F. )

    1994-10-24

    We have demonstrated efficient coupling of 0.35 [mu]m laser light for radiation production in inertial confinement fusion (ICF) cavity targets. Temperatures of 270 eV are measured in cavities used for implosions and 300 eV in smaller cavities, significantly extending the temperature range attained in the laboratory to those required for high-gain indirect drive ICF. High-contrast, shaped drive pulses required for implosion experiments have also been demonstrated for the first time. Low levels of scattered light and fast electrons are observed, indicating that plasma instability production is not significant.

  9. Sensitivity of mix in Inertial Confinement Fusion simulations to diffusion processes

    NASA Astrophysics Data System (ADS)

    Melvin, Jeremy; Cheng, Baolian; Rana, Verinder; Lim, Hyunkyung; Glimm, James; Sharp, David H.

    2015-11-01

    We explore two themes related to the simulation of mix within an Inertial Confinement Fusion (ICF) implosion, the role of diffusion (viscosity, mass diffusion and thermal conduction) processes and the impact of front tracking on the growth of the hydrodynamic instabilities. Using the University of Chicago HEDP code FLASH, we study the sensitivity of post-shot simulations of a NIC cryogenic shot to the diffusion models and front tracking of the material interfaces. Results of 1D and 2D simulations are compared to experimental quantities and an analysis of the current state of fully integrated ICF simulations is presented.

  10. Demonstration of Ignition Radiation Temperatures in Indirect-Drive Inertial Confinement Fusion Hohlraums

    NASA Astrophysics Data System (ADS)

    Glenzer, S. H.; MacGowan, B. J.; Meezan, N. B.; Adams, P. A.; Alfonso, J. B.; Alger, E. T.; Alherz, Z.; Alvarez, L. F.; Alvarez, S. S.; Amick, P. V.; Andersson, K. S.; Andrews, S. D.; Antonini, G. J.; Arnold, P. A.; Atkinson, D. P.; Auyang, L.; Azevedo, S. G.; Balaoing, B. N. M.; Baltz, J. A.; Barbosa, F.; Bardsley, G. W.; Barker, D. A.; Barnes, A. I.; Baron, A.; Beeler, R. G.; Beeman, B. V.; Belk, L. R.; Bell, J. C.; Bell, P. M.; Berger, R. L.; Bergonia, M. A.; Bernardez, L. J.; Berzins, L. V.; Bettenhausen, R. C.; Bezerides, L.; Bhandarkar, S. D.; Bishop, C. L.; Bond, E. J.; Bopp, D. R.; Borgman, J. A.; Bower, J. R.; Bowers, G. A.; Bowers, M. W.; Boyle, D. T.; Bradley, D. K.; Bragg, J. L.; Braucht, J.; Brinkerhoff, D. L.; Browning, D. F.; Brunton, G. K.; Burkhart, S. C.; Burns, S. R.; Burns, K. E.; Burr, B.; Burrows, L. M.; Butlin, R. K.; Cahayag, N. J.; Callahan, D. A.; Cardinale, P. S.; Carey, R. W.; Carlson, J. W.; Casey, A. D.; Castro, C.; Celeste, J. R.; Chakicherla, A. Y.; Chambers, F. W.; Chan, C.; Chandrasekaran, H.; Chang, C.; Chapman, R. F.; Charron, K.; Chen, Y.; Christensen, M. J.; Churby, A. J.; Clancy, T. J.; Cline, B. D.; Clowdus, L. C.; Cocherell, D. G.; Coffield, F. E.; Cohen, S. J.; Costa, R. L.; Cox, J. R.; Curnow, G. M.; Dailey, M. J.; Danforth, P. M.; Darbee, R.; Datte, P. S.; Davis, J. A.; Deis, G. A.; Demaret, R. D.; Dewald, E. L.; di Nicola, P.; di Nicola, J. M.; Divol, L.; Dixit, S.; Dobson, D. B.; Doppner, T.; Driscoll, J. D.; Dugorepec, J.; Duncan, J. J.; Dupuy, P. C.; Dzenitis, E. G.; Eckart, M. J.; Edson, S. L.; Edwards, G. J.; Edwards, M. J.; Edwards, O. D.; Edwards, P. W.; Ellefson, J. C.; Ellerbee, C. H.; Erbert, G. V.; Estes, C. M.; Fabyan, W. J.; Fallejo, R. N.; Fedorov, M.; Felker, B.; Fink, J. T.; Finney, M. D.; Finnie, L. F.; Fischer, M. J.; Fisher, J. M.; Fishler, B. T.; Florio, J. W.; Forsman, A.; Foxworthy, C. B.; Franks, R. M.; Frazier, T.; Frieder, G.; Fung, T.; Gawinski, G. N.; Gibson, C. R.; Giraldez, E.; Glenn, S. M.; Golick, B. P.; Gonzales, H.; Gonzales, S. A.; Gonzalez, M. J.; Griffin, K. L.; Grippen, J.; Gross, S. M.; Gschweng, P. H.; Gururangan, G.; Gu, K.; Haan, S. W.; Hahn, S. R.; Haid, B. J.; Hamblen, J. E.; Hammel, B. A.; Hamza, A. V.; Hardy, D. L.; Hart, D. R.; Hartley, R. G.; Haynam, C. A.; Heestand, G. M.; Hermann, M. R.; Hermes, G. L.; Hey, D. S.; Hibbard, R. L.; Hicks, D. G.; Hinkel, D. E.; Hipple, D. L.; Hitchcock, J. D.; Hodtwalker, D. L.; Holder, J. P.; Hollis, J. D.; Holtmeier, G. M.; Huber, S. R.; Huey, A. W.; Hulsey, D. N.; Hunter, S. L.; Huppler, T. R.; Hutton, M. S.; Izumi, N.; Jackson, J. L.; Jackson, M. A.; Jancaitis, K. S.; Jedlovec, D. R.; Johnson, B.; Johnson, M. C.; Johnson, T.; Johnston, M. P.; Jones, O. S.; Kalantar, D. H.; Kamperschroer, J. H.; Kauffman, R. L.; Keating, G. A.; Kegelmeyer, L. M.; Kenitzer, S. L.; Kimbrough, J. R.; King, K.; Kirkwood, R. K.; Klingmann, J. L.; Knittel, K. M.; Kohut, T. R.; Koka, K. G.; Kramer, S. W.; Krammen, J. E.; Krauter, K. G.; Krauter, G. W.; Krieger, E. K.; Kroll, J. J.; La Fortune, K. N.; Lagin, L. J.; Lakamsani, V. K.; Landen, O. L.; Lane, S. W.; Langdon, A. B.; Langer, S. H.; Lao, N.; Larson, D. W.; Latray, D.; Lau, G. T.; Le Pape, S.; Lechleiter, B. L.; Lee, Y.; Lee, T. L.; Li, J.; Liebman, J. A.; Lindl, J. D.; Locke, S. F.; Loey, H. K.; London, R. A.; Lopez, F. J.; Lord, D. M.; Lowe-Webb, R. R.; Lown, J. G.; Ludwigsen, A. P.; Lum, N. W.; Lyons, R. R.; Ma, T.; MacKinnon, A. J.; Magat, M. D.; Maloy, D. T.; Malsbury, T. N.; Markham, G.; Marquez, R. M.; Marsh, A. A.; Marshall, C. D.; Marshall, S. R.; Maslennikov, I. L.; Mathisen, D. G.; Mauger, G. J.; Mauvais, M.-Y.; McBride, J. A.; McCarville, T.; McCloud, J. B.; McGrew, A.; McHale, B.; Macphee, A. G.; Meeker, J. F.; Merill, J. S.; Mertens, E. P.; Michel, P. A.; Miller, M. G.; Mills, T.; Milovich, J. L.; Miramontes, R.; Montesanti, R. C.; Montoya, M. M.; Moody, J.; Moody, J. D.; Moreno, K. A.; Morris, J.; Morriston, K. M.; Nelson, J. R.; Neto, M.; Neumann, J. D.; Ng, E.; Ngo, Q. M.; Olejniczak, B. L.; Olson, R. E.; Orsi, N. L.; Owens, M. W.; Padilla, E. H.; Pannell, T. M.; Parham, T. G.; Patterson, R. W., Jr.; Pavel, G.; Prasad, R. R.; Pendlton, D.; Penko, F. A.; Pepmeier, B. L.; Petersen, D. E.; Phillips, T. W.; Pigg, D.; Piston, K. W.; Pletcher, K. D.; Powell, C. L.; Radousky, H. B.; Raimondi, B. S.; Ralph, J. E.; Rampke, R. L.; Reed, R. K.; Reid, W. A.; Rekow, V. V.; Reynolds, J. L.; Rhodes, J. J.; Richardson, M. J.; Rinnert, R. J.; Riordan, B. P.; Rivenes, A. S.; Rivera, A. T.; Roberts, C. J.; Robinson, J. A.; Robinson, R. B.; Robison, S. R.; Rodriguez, O. R.; Rogers, S. P.; Rosen, M. D.; Ross, G. F.; Runkel, M.; Runtal, A. S.; Sacks, R. A.; Sailors, S. F.; Salmon, J. T.; Salmonson, J. D.; Saunders, R. L.; Schaffer, J. R.; Schindler, T. M.; Schmitt, M. J.; Schneider, M. B.; Segraves, K. S.; Shaw, M. J.; Sheldrick, M. E.; Shelton, R. T.; Shiflett, M. K.; Shiromizu, S. J.; Shor, M.; Silva, L. L.; Silva, S. A.; Skulina, K. M.; Smauley, D. A.; Smith, B. E.; Smith, L. K.; Solomon, A. L.; Sommer, S.; Soto, J. G.; Spafford, N. I.; Speck, D. E.; Springer, P. T.; Stadermann, M.; Stanley, F.; Stone, T. G.; Stout, E. A.; Stratton, P. L.; Strausser, R. J.; Suter, L. J.; Sweet, W.; Swisher, M. F.; Tappero, J. D.; Tassano, J. B.; Taylor, J. S.; Tekle, E. A.; Thai, C.; Thomas, C. A.; Thomas, A.; Throop, A. L.; Tietbohl, G. L.; Tillman, J. M.; Town, R. P. J.; Townsend, S. L.; Tribbey, K. L.; Trummer, D.; Truong, J.; Vaher, J.; Valadez, M.; van Arsdall, P.; van Prooyen, A. J.; Vergel de Dios, E. O.; Vergino, M. D.; Vernon, S. P.; Vickers, J. L.; Villanueva, G. T.; Vitalich, M. A.; Vonhof, S. A.; Wade, F. E.; Wallace, R. J.; Warren, C. T.; Warrick, A. L.; Watkins, J.; Weaver, S.; Wegner, P. J.; Weingart, M. A.; Wen, J.; White, K. S.; Whitman, P. K.; Widmann, K.; Widmayer, C. C.; Wilhelmsen, K.; Williams, E. A.; Williams, W. H.; Willis, L.; Wilson, E. F.; Wilson, B. A.; Witte, M. C.; Work, K.; Yang, P. S.; Young, B. K.; Youngblood, K. P.; Zacharias, R. A.; Zaleski, T.; Zapata, P. G.; Zhang, H.; Zielinski, J. S.; Kline, J. L.; Kyrala, G. A.; Niemann, C.; Kilkenny, J. D.; Nikroo, A.; van Wonterghem, B. M.; Atherton, L. J.; Moses, E. I.

    2011-02-01

    We demonstrate the hohlraum radiation temperature and symmetry required for ignition-scale inertial confinement fusion capsule implosions. Cryogenic gas-filled hohlraums with 2.2 mm-diameter capsules are heated with unprecedented laser energies of 1.2 MJ delivered by 192 ultraviolet laser beams on the National Ignition Facility. Laser backscatter measurements show that these hohlraums absorb 87% to 91% of the incident laser power resulting in peak radiation temperatures of TRAD=300eV and a symmetric implosion to a 100μm diameter hot core.

  11. Simulations of mixing in Inertial Confinement Fusion with front tracking and sub-grid scale models

    NASA Astrophysics Data System (ADS)

    Rana, Verinder; Lim, Hyunkyung; Melvin, Jeremy; Cheng, Baolian; Glimm, James; Sharp, David

    2015-11-01

    We present two related results. The first discusses the Richtmyer-Meshkov (RMI) and Rayleigh-Taylor instabilities (RTI) and their evolution in Inertial Confinement Fusion simulations. We show the evolution of the RMI to the late time RTI under transport effects and tracking. The role of the sub-grid scales helps capture the interaction of turbulence with diffusive processes. The second assesses the effects of concentration on the physics model and examines the mixing properties in the low Reynolds number hot spot. We discuss the effect of concentration on the Schmidt number. The simulation results are produced using the University of Chicago code FLASH and Stony Brook University's front tracking algorithm.

  12. K-alpha conversion efficiency measurments for x-ray scattering in inertial confinement fusion plasmas

    SciTech Connect

    Kritcher, A L; Neumayer, P; Urry, M K; Robey, H; Niemann, C; Landen, O L; Morse, E; Glenzer, S H

    2006-11-21

    The conversion efficiency of ultra short-pulse laser radiation to K-{alpha} x-rays has been measured for various chlorine-containing targets to be used as x-ray scattering probes of dense plasmas. The spectral and temporal properties of these sources will allow spectrally-resolved x-ray scattering probing with picosecond temporal resolution required for measuring the plasma conditions in inertial confinement fusion experiments. Simulations of x-ray scattering spectra from these plasmas show that fuel capsule density, capsule ablator density, and shock timing information may be inferred.

  13. A strategy for reducing stagnation phase hydrodynamic instability growth in inertial confinement fusion implosions

    NASA Astrophysics Data System (ADS)

    Clark, D. S.; Robey, H. F.; Smalyuk, V. A.

    2015-05-01

    Encouraging progress is being made in demonstrating control of ablation front hydrodynamic instability growth in inertial confinement fusion implosion experiments on the National Ignition Facility [E. I. Moses, R. N. Boyd, B. A. Remington, C. J. Keane, and R. Al-Ayat, Phys. Plasmas 16, 041006 (2009)]. Even once ablation front stabilities are controlled, however, instability during the stagnation phase of the implosion can still quench ignition. A scheme is proposed to reduce the growth of stagnation phase instabilities through the reverse of the "adiabat shaping" mechanism proposed to control ablation front growth. Two-dimensional radiation hydrodynamics simulations confirm that improved stagnation phase stability should be possible without compromising fuel compression.

  14. A 3-D Model of Hot-Spot Formation in Inertial Confinement Fusion Implosions

    NASA Astrophysics Data System (ADS)

    Gong, X.; Goncharov, V. N.; Igumenshchev, I. V.

    2015-11-01

    A 3-D model describing the formation of a hot-spot in inertial confinement fusion (ICF) implosions is presented. The model includes thermal conduction and mass ablation effects in a 3-D distorted hot spot using an approach developed by Sanz. Evolution of the nonuniformity growth is calculated based on a sharp boundary model. The results of the model will be compared against 2-D DRACO and 3-D hydrodynamic code calculations. This material is based upon work supported by the Department of Energy National Nuclear Security Administration under Award Number DE-NA0001944.

  15. Transport vehicle for manned Mars missions powered by inertial confinement fusion

    NASA Technical Reports Server (NTRS)

    Orth, Charles D.; Klein, Gail; Sercel, Joel; Hoffman, Nathan; Murray, Kathy; Chang-Diaz, Franklin

    1987-01-01

    Inertial confinement fusion (ICF) is an ideal engine power source for manned spacecraft to Mars because of its inherently high power-to-mass ratios and high specific impulses. In this paper a concept is produced for a vehicle powered by ICF and utilizing a magnetic thrust chamber to avoid plasma thermalization with wall structures and the resultant degradation of specific impulse, that are unavoidable with the use of mechanical thrust chambers. This vehicle is capable of 100-day manned Mars missions with a 100-metric-ton payload and a total vehicle launch mass near 6000 metric tons, based on advanced technology assumed to be available by A.D. 2020.

  16. Multi-fluid studies of plasma shocks relevant to inertial confinement fusion

    NASA Astrophysics Data System (ADS)

    Srinivasan, B.; Kagan, G.; Adams, C. S.

    2016-05-01

    Results from inertial confinement fusion (ICF) experiments performed at the Omega laser facility suggest the potential role of kinetic effects in plasmas during implosion. Recent theoretical and numerical work has indicated the importance of diffusion effects in the presence of multiple ion species as well as the importance of ion viscosity. This provides the motivation to adequately develop multi-fluid plasma models capable of capturing kinetic physics including concentration diffusion and ion species separation driven by the ion concentration gradient, the ion pressure gradient, the electron and ion temperature gradients, and the electric field. Benchmarks between the newly developed code and analytical results are presented for multi-fluid plasma shocks.

  17. Analysis of the neutron time-of-flight spectra from inertial confinement fusion experiments

    DOE PAGESBeta

    Hatarik, R.; Sayre, D. B.; Caggiano, J. A.; Phillips, T.; Eckart, M. J.; Bond, E. J.; Cerjan, C.; Grim, G. P.; Hartouni, E. P.; Knauer, J. P.; et al

    2015-11-12

    For a long time, neutron time-of-flight diagnostics been used to characterize the neutron spectrum produced by inertial confinement fusion experiments. The primary diagnostic goals are to extract the d+t→n+α (DT) and d+d→n+³He (DD) neutron yields and peak widths, and the amount DT scattering relative to its unscattered yield, which is also known as the down-scatter ratio (DSR). These quantities are used to infer yield weighted plasma conditions, such as ion temperature (Tion) and cold fuel areal density. We explain such novel methodologies used to determine neutron yield, apparent Tion and DSR.

  18. Analysis of the neutron time-of-flight spectra from inertial confinement fusion experiments

    SciTech Connect

    Hatarik, R.; Sayre, D. B.; Caggiano, J. A.; Phillips, T.; Eckart, M. J.; Bond, E. J.; Cerjan, C.; Grim, G. P.; Hartouni, E. P.; Knauer, J. P.; Mcnaney, J. M.; Munro, D. H.

    2015-11-12

    For a long time, neutron time-of-flight diagnostics been used to characterize the neutron spectrum produced by inertial confinement fusion experiments. The primary diagnostic goals are to extract the d+t→n+α (DT) and d+d→n+³He (DD) neutron yields and peak widths, and the amount DT scattering relative to its unscattered yield, which is also known as the down-scatter ratio (DSR). These quantities are used to infer yield weighted plasma conditions, such as ion temperature (Tion) and cold fuel areal density. We explain such novel methodologies used to determine neutron yield, apparent Tion and DSR.

  19. Multiple-beam laser–plasma interactions in inertial confinement fusion

    SciTech Connect

    Myatt, J. F. Zhang, J.; Maximov, A. V.; Short, R. W.; Seka, W.; Edgell, D. H.; Michel, D. T.; Igumenshchev, I. V.; Froula, D. H.; Hinkel, D. E.; Michel, P.; Moody, J. D.

    2014-05-15

    The experimental evidence for multiple-beam laser-plasma instabilities of relevance to laser driven inertial confinement fusion at the ignition scale is reviewed, in both the indirect and direct-drive approaches. The instabilities described are cross-beam energy transfer (in both indirectly driven targets on the NIF and in direct-drive targets), multiple-beam stimulated Raman scattering (for indirect-drive), and multiple-beam two-plasmon decay instability (in direct drive). Advances in theoretical understanding and in the numerical modeling of these multiple beam instabilities are presented.

  20. Indirect-drive inertial confinement fusion using highly supersonic, radiatively cooled, plasma slugs.

    PubMed

    Chittenden, J P; Dunne, M; Zepf, M; Lebedev, S V; Ciardi, A; Bland, S N

    2002-06-10

    We present a new approach to indirect-drive inertial confinement fusion which makes use of highly supersonic, radiatively cooled, slugs of plasma to energize a hohlraum. 2D resistive magnetohydrodynamic simulations of slug formation in shaped liner Z-pinch implosions are presented along with 2D-radiation-hydrodynamic simulations of the slug impacting a converter foil and 3D-view-factor simulations of a double-ended hohlraum. Results for the Z facility at Sandia National Laboratory indicate that two synchronous slugs of 250 kJ kinetic energy could be produced, resulting in a capsule surface temperature of approximately 225 eV. PMID:12059369

  1. Apparatus and method for removing particle species from fusion-plasma-confinement devices

    DOEpatents

    Hamilton, G.W.

    1981-10-26

    In a mirror fusion plasma confinement apparatus, method and apparatus are provided for selectively removing (pumping) trapped low energy (thermal) particle species from the end cell region, without removing the still useful high energy particle species, and without requiring large power input to accomplish the pumping. Perturbation magnets are placed in the thermal barrier region of the end cell region at the turning point characteristic of trapped thermal particles, thus deflecting the thermal particles from their closed trajectory, causing them to drift sufficiently to exit the thermal barrier.

  2. Magnetic field generation in Rayleigh-Taylor unstable inertial confinement fusion plasmas.

    PubMed

    Srinivasan, Bhuvana; Dimonte, Guy; Tang, Xian-Zhu

    2012-04-20

    Rayleigh-Taylor instabilities (RTI) in inertial confinement fusion implosions are expected to generate magnetic fields. A Hall-MHD model is used to study the field generation by 2D single-mode and multimode RTI in a stratified two-fluid plasma. Self-generated magnetic fields are predicted and these fields grow as the RTI progresses via the ∇n(e)×∇T(e) term in the generalized Ohm's law. Scaling studies are performed to determine the growth of the self-generated magnetic field as a function of density, acceleration, Atwood number, and perturbation wavelength. PMID:22680725

  3. A scheme for reducing deceleration-phase Rayleigh-Taylor growth in inertial confinement fusion implosions

    NASA Astrophysics Data System (ADS)

    Wang, L. F.; Ye, W. H.; Wu, J. F.; Liu, Jie; Zhang, W. Y.; He, X. T.

    2016-05-01

    It is demonstrated that the growth of acceleration-phase instabilities in inertial confinement fusion implosions can be controlled, especially in the high-foot implosions [O. A. Hurricane et al., Phys. Plasmas 21, 056314 (2014)] on the National Ignition Facility. However, the excessive growth of the deceleration-phase instabilities can still destroy the hot spot ignition. A scheme is proposed to retard the deceleration-phase Rayleigh-Taylor instability growth by shock collision near the waist of the inner shell surface. Two-dimensional radiation hydrodynamic simulations confirm the improved deceleration-phase hot spot stability properties without sacrificing the fuel compression.

  4. HYPERFUSE: a hypervelocity inertial confinement system for fusion energy production and fission waste transmutation

    SciTech Connect

    Makowitz, H.; Powell, J.R.; Wiswall, R.

    1980-01-01

    Parametric system studies of an inertial confinement fusion (ICF) reactor system to transmute fission products from a LWR economy have been carried out. The ICF reactors would produce net power in addition to transmuting fission products. The particular ICF concept examined is an impact fusion approach termed HYPERFUSE, in which hypervelocity pellets, traveling on the order of 100 to 300 km/sec, collide with each other or a target block in a reactor chamber and initiate a thermonuclear reaction. The DT fusion fuel is contained in a shell of the material to be transmuted, e.g., /sup 137/Cs, /sup 90/Sr, /sup 129/I, /sup 99/Tc, etc. The 14-MeV fusion neutrons released during the pellet burn cause transmutation reactions (e.g., (n,2n), (n,..cap alpha..), (n,..gamma..), etc.) that convert the long-lived fission products (FP's) either to stable products or to species that decay with a short half-life to a stable product. The transmutation parametric studies conclude that the design of the hypervelocity projectiles should emphasize the achievement of high densities in the transmutation regions (greater than the DT fusion fuel density), as well as the DT ignition and burn criterion (rho R = 1.0 to 3.0) requirements. These studies also indicate that masses on the order of 1.0 g at densities of rho greater than or equal to 500.0 g/cm/sup 3/ are required for a practical fusion-based fission product transmutation system.

  5. Transport implications of hydrodynamic mix on hot-spot performance in inertial confinement fusion

    NASA Astrophysics Data System (ADS)

    Srinivasan, Bhuvana; Tang, Xianzhu

    2014-10-01

    In an inertial confinement fusion target, energy loss due to thermal conduction from the hot-spot will inevitably ablate fuel ice into the hot-spot, resulting in a more massive but cooler hot-spot, which negatively impacts fusion yield. Hydrodynamic mix due to the Rayleigh-Taylor instability at the gas-ice interface can aggravate the problem via an increased gas-ice interfacial area across which energy transfer from the hot-spot and ice can be enhanced. We quantify this mix-enhanced transport effect on hot-spot fusion-performance degradation using contrasting 1-D and 2-D hydrodynamic simulations, and identify its dependence on effective acceleration, Atwood number, and ablation speed. In the presence of magnetic fields, the thermal conduction is reduced which reduces the effect of ablative stabilization on mix mitigation while also reducing the amount of cold fuel being ablated into the hot-spot. A characterization of the transport enhanced mix characteristics with and without magnetic fields is performed to identify a regime where fusion-performance degradation is reduced by mix mitigation, through which the amount of cold fuel being ablated into the hot-spot is minimized.

  6. Production and measurement of engineered surfaces for inertial confinement fusion research

    SciTech Connect

    Day, Robert D; Hatch, Douglas J; Rivera, Gerald

    2011-01-19

    Inertial Confinement Fusion uses the optical energy from a very high power laser to implode spherical capsules that contain a fuel mixture of deuterium and tritium. The capsules are made of either Beryllium, plastic, or glass and range from 0.1 mm to 2 mm in diameter. As a capsule implodes, thereby compressing the fuel to reach nuclear fusion conditions, it achieves temperatures of millions of degrees Centigrade and very high pressures. In this state, the capsule materials act like fluids and often a low density fluidic material will push on a higher density material which can be a very unstable condition depending upon the smoothness of the interface between the two materials. This unstable condition is called a hydrodynamic instabillity which results in the mixing of the two materials. If the mixing occurs between the fuel and a non-fuel material, it can stop the fusion reaction just like adding significant amounts of water to gasoline can stop the operation of an automobile. Another region in the capsule where surface roughness can cause capsule performance degradation is at a joint. For instance, many capsules are made of hemispheres that are joined together. If the joint surfaces are too rough, then there will an effective reduction in density at the joint. This density reduction can cause a non-uniform implosion which will reduce the fusion energy coming out of the capsule.

  7. Simulating the magnetized liner inertial fusion plasma confinement with smaller-scale experiments [Simulating the MagLIF plasma confinement with smaller-scale experiments

    SciTech Connect

    Ryutov, D. D.; Cuneo, M. E.; Herrmann, M. C.; Sinars, D. B.; Slutz, S. A.

    2012-06-20

    The recently proposed magnetized liner inertial fusion approach to a Z-pinch driven fusion [Slutz et al., Phys. Plasmas17, 056303 (2010)] is based on the use of an axial magnetic field to provide plasma thermal insulation from the walls of the imploding liner. The characteristic plasma transport regimes in the proposed approach cover parameter domains that have not been studied yet in either magnetic confinement or inertial confinement experiments. In this article, an analysis is presented of the scalability of the key physical processes that determine the plasma confinement. The dimensionless scaling parameters are identified and conclusion is drawn that the plasma behavior in scaled-down experiments can correctly represent the full-scale plasma, provided these parameters are approximately the same in two systems. Furthermore, this observation is important in that smaller-scale experiments typically have better diagnostic access and more experiments per year are possible.

  8. Scientific and Computational Challenges of the Fusion Simulation Program (FSP)

    SciTech Connect

    William M. Tang

    2011-02-09

    This paper highlights the scientific and computational challenges facing the Fusion Simulation Program (FSP) a major national initiative in the United States with the primary objective being to enable scientific discovery of important new plasma phenomena with associated understanding that emerges only upon integration. This requires developing a predictive integrated simulation capability for magnetically-confined fusion plasmas that are properly validated against experiments in regimes relevant for producing practical fusion energy. It is expected to provide a suite of advanced modeling tools for reliably predicting fusion device behavior with comprehensive and targeted science-based simulations of nonlinearly-coupled phenomena in the core plasma, edge plasma, and wall region on time and space scales required for fusion energy production. As such, it will strive to embody the most current theoretical and experimental understanding of magnetic fusion plasmas and to provide a living framework for the simulation of such plasmas as the associated physics understanding continues to advance over the next several decades. Substantive progress on answering the outstanding scientific questions in the field will drive the FSP toward its ultimate goal of developing the ability to predict the behavior of plasma discharges in toroidal magnetic fusion devices with high physics fidelity on all relevant time and space scales. From a computational perspective, this will demand computing resources in the petascale range and beyond together with the associated multi-core algorithmic formulation needed to address burning plasma issues relevant to ITER - a multibillion dollar collaborative experiment involving seven international partners representing over half the world's population. Even more powerful exascale platforms will be needed to meet the future challenges of designing a demonstration fusion reactor (DEMO). Analogous to other major applied physics modeling projects (e

  9. Inertial confinement fusion target component fabrication and technology development support: Annual report, October 1, 1993--September 30, 1994

    SciTech Connect

    Hoppe, M.

    1995-04-01

    On December 30, 1990, the US Department of Energy entered into a contract with General Atomics (GA) to be the Inertial Confinement Fusion (ICF) Target Component Fabrication and Technology Development Support contractor. During the period, GA was assigned 17 tasks in support of the Inertial Confinement Fusion program and its laboratories. This year they achieved full production capabilities for the micromachining, dimensional characterization and gold plating of hohlraums. They fabricated and delivered 726 gold-plated mandrels of 27 different types to LLNL and 48 gold-plated mandrels of two different types to LANL. They achieved full production capabilities in composite capsule production ad delivered in excess of 240 composite capsules. They continuously work to improve performance and capabilities. They were also directed to dismantle, remove, and disposition all equipment at the previous contractor (KMSF) that had radioactive contamination levels low enough that they could be exposed to the general public without radiological constraints. GA was also directed to receive and store the tritium fill equipment. They assisted LANL in the development of techniques for characterization of opaque targets. They developed deuterated and UV-opaque polymers for use by the University of Rochester`s Laboratory for Laser Energetics (UR/LLE) and devised a triple-orifice droplet generator to demonstrate the controlled-mass nature of the microencapsulation process. The ICF program is anticipating experiments at NIF and the Omega Upgrade. Both facilities will require capsules containing layered D{sub 2} or D-T fuel. They continued engineering and assembly of equipment for a cryogenic target handling system for UR/LLE that will fill, transport, layer, and characterize targets filled with cryogenic deuterium or deuterium-tritium fuel, and insert these cryogenic targets into the OMEGA Upgrade target chamber for laser implosion experiments.

  10. Hard x-ray backlighters for high resolution Compton radiography of Inertial Confinement Fusion targets

    NASA Astrophysics Data System (ADS)

    Tommasini, R.; Macphee, A.; Hey, D.; Ma, T.; Chen, C.; Izumi, N.; MacKinnon, A.; Hatchett, S. P.; Koch, J. A.; Springer, P.; Landen, O. L.

    2008-11-01

    Radiographs of the final stages of imploding DT fuel in inertial confinement fusion experiments will be extremely valuable for checking the convergence, areal density and areal density uniformity of the fuel. For x-rays with energies between 30 and 200 keV, the main opacity will be due to Compton scattering. Here we present the demonstration of 75-200 keV point backlighter sources generated by gold targets irradiated by picosecond laser pulses. In experiments performed at the Titan laser facility at Lawrence Livermore National Laboratory, we measured the source size and the Bremsstrahlung spectrum, as a function of laser intensity and pulse length, from by 5e17-5e18 W/cm^2 using 2-40 ps pulses. We achieved 1D and 2D source sizes of 10 μm, and conversion efficiencies exceeding 1e-3 J/J into x-ray photons with energies in the 100-200 keV spectral range. These sources meet the requirements for radiographing the fuel in inertial confinement fusion implosions at both OMEGA and the National Ignition Facility (NIF) whose experimental designs will also be discussed.

  11. A program toward a fusion reactor

    NASA Astrophysics Data System (ADS)

    Rebut, P.-H.; Watkins, M. L.; Gambier, D. J.; Boucher, D.

    1991-08-01

    Near breakeven conditions have been attained in the JET tokamak [Fusion Technol. 11, 13 (1987)], with beryllium as the first-wall material. A fusion triple product (nDτETi) of 8-9×1020 m-3 sec keV has been reached (within a factor of 8 of that required in a fusion reactor). However, this has only been achieved transiently. At high heating powers, an influx of impurities still limits the achievement of better performance and steady-state operation. In parallel, an improved quantitative understanding of fusion plasmas has emerged from the development of a particular plasma model. Good quantitative agreement is obtained between the model and JET data. The main predictions are also consistent with statistical scaling laws. With such a model, a predictive capability begins to emerge to define the parameters and operating conditions of a DEMO, including impurity levels. Present experimental results and model predictions suggest that impurity dilution is a major threat to a reactor. A divertor concept must be developed further to ensure impurity control before a DEMO can be constructed. A New Phase for JET is planned in which an axisymmetric pumped divertor configuration will be used to address the problems of impurity control, plasma fueling, and helium ash exhaust. It should demonstrate a concept of impurity control and the operational domain for such a device. A single Next Step facility (ITER) is a high risk strategy in terms of physics, technology, and management, since it does not provide a sufficiently sound foundation for a DEMO. A Next Step program is proposed, which could comprise several complementary facilities, each optimized with respect to specific clear objectives. In a minimum program, there could be two Next Step tokamaks, and a Materials Test Facility. Such a program would allow division of effort and sharing of risk across the various scientific and technical problems, permit cross comparison, and ensure continuity of results. It could even be

  12. Fusion reactivity, confinement, and stability of neutral-beam heated plasmas in TFTR and other tokamaks

    SciTech Connect

    Park, Hyeon, K.; Sabbagh, S.A.

    1996-05-01

    The hypothesis that the heating beam fueling profile shape connects the edge condition and improved core confinement and fusion reactivity is extensively studied on TFTR and applied to other tokamaks. The derived absolute scalings based on beam fueling profile shape for the stored energy and neutron yield can be applied to the deuterium discharges at different major radii in TFTR. These include Supershot, High poloidal beta, L-mode, and discharges with a reversed shear (RS) magnetic configuration. These scalings are also applied to deuterium-tritium discharges. The role of plasma parameters, such as plasma current, Isdo2(p), edge safety factor, qsdo5(a), and toroidal field, Bsdo2(T), in the performance and stability of the discharges is explicitly studied. Based on practical and externally controllable plasma parameters, the limitation and optimization of fusion power production of the present TFTR is investigated and a path for a discharge condition with fusion power gain, Q > 1 is suggested based on this study. Similar physics interpretation is provided for beam heated discharges on other major tokamaks.

  13. Fatigue cracking of a bare steel first wall in an inertial confinement fusion chamber

    SciTech Connect

    Hunt, R. M.; Abbott, R. P.; Havstad, M. A.; Dunne, A. M.

    2013-06-01

    Inertial confinement fusion power plants will deposit high energy X-rays onto the outer surfaces of the first wall many times a second for the lifetime of the plant. These X-rays create brief temperature spikes in the first few microns of the wall, which cause an associated highly compressive stress response on the surface of the material. The periodicity of this stress pulse is a concern due to the possibility of fatigue cracking of the wall. We have used finite element analyses to simulate the conditions present on the first wall in order to evaluate the driving force of crack propagation on fusion-facing surface cracks. Analysis results indicate that the X-ray induced plastic compressive stress creates a region of residual tension on the surface between pulses. This tension film will likely result in surface cracking upon repeated cycling. Additionally, the compressive pulse may induce plasticity ahead of the crack tip, leaving residual tension in its wake. However, the stress amplitude decreases dramatically for depths greater than 80–100 μm into the fusion-facing surface. Crack propagation models as well as stress-life estimates agree that even though small cracks may form on the surface of the wall, they are unlikely to propagate further than 100 μm without assistance from creep or grain erosion phenomena.

  14. Inertial confinement fusion reaction chamber and power conversion system study. Final report

    SciTech Connect

    Maya, I.; Schultz, K.R.; Bourque, R.F.; Cheng, E.T.; Creedon, R.L.; Norman, J.H.; Price, R.J.; Porter, J.; Schuster, H.L.; Simnad, M.J.

    1985-10-01

    This report summarizes the results of the second year of a two-year study on the design and evaluation of the Cascade concept as a commercial inertial confinement fusion (ICF) reactor. We developed a reactor design based on the Cascade reaction chamber concept that would be competitive in terms of both capital and operating costs, safe and environmentally acceptable in terms of hazard to the public, occupational exposure and radioactive waste production, and highly efficient. The Cascade reaction chamber is a double-cone-shaped rotating drum. The granulated solid blanket materials inside the rotating chamber are held against the walls by centrifugal force. The fusion energy is captured in a blanket of solid carbon, BeO, and LiAlO/sub 2/ granules. These granules are circulated to the primary side of a ceramic heat exchanger. Primary-side granule temperatures range from 1285 K at the LiAlO/sub 2/ granule heat exchanger outlet to 1600 K at the carbon granule heat exchanger inlet. The secondary side consists of a closed-cycle gas turbine power conversion system with helium working fluid, operating at 1300 K peak outlet temperature and achieving a thermal power conversion efficiency of 55%. The net plant efficiency is 49%. The reference design is a plant producing 1500 MW of D-T fusion power and delivering 815 MW of electrical power for sale to the utility grid. 88 refs., 44 figs., 47 tabs.

  15. Inertial Confinement Fusion Target Component Fabrication and Technology Development report. Annual report, October 1, 1992--September 30, 1993

    SciTech Connect

    Steinman, D.

    1994-03-01

    On December 30, 1990, the US Department of Energy entered into a contract with General Atomics (GA) to be the Inertial Confinement Fusion Target Component Fabrication and Technology Development Support contractor. This report documents the technical activities which took place under this contract during the period of October 1, 1992 through September 30, 1993. During this period, GA was assigned 18 tasks in support of the Inertial Confinement Fusion program and its laboratories. These tasks included ``Capabilities Activation`` and ``Capabilities Demonstration`` to enable us to begin production of glass and composite polymer capsules. Capsule delivery tasks included ``Small Glass Shell Deliveries`` and ``Composite Polymer Capsules`` for Lawrence Livermore National Laboratory (LLNL) and Los Alamos National Laboratory (LANL). We also were asked to provide direct ``Onsite Support`` at LLNL and LANL. We continued planning for the transfer of ``Micromachining Equipment from Rocky Flats`` and established ``Target Component Micromachining and Electroplating Facilities`` at GA. We fabricated over 1100 films and filters of 11 types for Sandia National Laboratory and provided full-time onsite engineering support for target fabrication and characterization. We initiated development of methods to make targets for the Naval Research Laboratory. We investigated spherical interferometry, built an automated capsule sorter, and developed an apparatus for calorimetric measurement of fuel fill for LLNL. We assisted LANL in the ``Characterization of Opaque b-Layered Targets.`` We developed deuterated and UV-opaque polymers for use by the University of Rochester`s Laboratory for Laser Energetics (UR/LLE) and devised a triple-orifice droplet generator to demonstrate the controlled-mass nature of the microencapsulation process.

  16. Inertial Confinement Fusion Target Component Fabrication and Technology Development Support. Annual report, January 1, 1991--September 30, 1992

    SciTech Connect

    Steinman, D.

    1993-03-01

    On December 31, 1990, the US Department of Energy entered into a contract with General Atomics (GA) to be the Inertial Confinement Fusion (ICF) Target Component Fabrication and Technology Development Support contractor. This report documents the technical activities of the period January 1, 1991 through September 30, 1992. During this period, GA was assigned 15 tasks in support of the Inertial Confinement Fusion program and its laboratories. These tasks included Facilities Activation, Staff Development, and Capabilities Validation to establish facilities and equipment, and demonstrate capability to perform ICF target fabrication research, development and production activities. The capabilities developed and demonstrated are those needed for fabrication and precise characterization of polymer shells and polymer coatings. We made progress toward production capability for glass shells, barrier layer coatings, and gas idling of shells. We fabricated over 1000 beam diagnostic foil targets for Sandia National Laboratory Albuquerque and provided full-time on-site engineering support for target fabrication and characterization. We initiated development of methods to fabricate polymer shells by a controlled mass microencapsulation technique, and performed chemical syntheses of several chlorine- and silicon-doped polymer materials for the University of Rochester`s Laboratory for Laser Energetics (UR/LLE). We performed the conceptual design of a cryogenic target handling system for UR/LLE that will fill, transport, layer, and characterize targets filled with cryogenic deuterium or deuterium-tritium fuel, and insert these cryogenic targets into the OMEGA-Upgrade target chamber for laser implosion experiments. This report summarizes and documents the technical progress made on these tasks.

  17. Effect of the laser wavelength: A long story of laser-plasma interaction physics for Inertial Confinement Fusion Teller Medal Lecture

    NASA Astrophysics Data System (ADS)

    Labaune, Christine

    2013-11-01

    Laser-driven Inertial Confinement Fusion (ICF) relies on the use of high-energy laser beams to compress and ignite a thermonuclear fuel with the ultimate goal of producing energy. Fusion is the holy grail of energy sources-combining abundant fuel with no greenhouse gas emissions, minimal waste products and a scale that can meet mankind's long-term energy demands. The quality and the efficiency of the coupling of the laser beams with the target are an essential step towards the success of laser fusion. A long-term program on laser-plasma interaction physics has been pursued to understand the propagation and the coupling of laser pulses in plasmas for a wide range of parameters.

  18. On the use of particle-in-cell methods for the study of magnetically-confined fusion plasmas

    SciTech Connect

    Procassini, R.J. California Univ., Berkeley, CA . Electronics Research Lab.)

    1991-06-12

    The applicability of electrostatic particle-in-cell (PIC) methods for the simulation of magnetically-confined fusion plasmas is investigated. The aspects of the PIC methodology which allow one to accurately model the representative charge separations found in hot fusion plasmas with far fewer simulation particles are discussed. The number of simulation particles required to resolve the collective effects of interest (such as the ambipolar potential) above the statistical fluctuations is also analyzed. 8 refs., 1 fig.

  19. Change in inertial confinement fusion implosions upon using an ab initio multiphase DT equation of state.

    PubMed

    Caillabet, L; Canaud, B; Salin, G; Mazevet, S; Loubeyre, P

    2011-09-01

    Improving the description of the equation of state (EOS) of deuterium-tritium (DT) has recently been shown to change significantly the gain of an inertial confinement fusion target [S. X. Hu et al., Phys. Rev. Lett. 104, 235003 (2010)]. Here we use an advanced multiphase EOS, based on ab initio calculations, to perform a full optimization of the laser pulse shape with hydrodynamic simulations starting from 19 K in DT ice. The thermonuclear gain is shown to be a robust estimate over possible uncertainties of the EOS. Two different target designs are discussed, for shock ignition and self-ignition. In the first case, the areal density and thermonuclear energy can be recovered by slightly increasing the laser energy. In the second case, a lower in-flight adiabat is needed, leading to a significant delay (3 ns) in the shock timing of the implosion. PMID:22026681

  20. Investigation of methods for fabricating, characterizing, and transporting cryogenic inertial-confinement-fusion tartets

    SciTech Connect

    Fanning, J.J.; Kim, K.

    1981-01-01

    The objective of this work is to investigate methods for fabricating, characterizing and transporting cryogenic inertial confinement fusion targets on a continuous basis. A microprocessor-based data acquisition system has been built that converts a complete target image to digital data, which are then analyzed by automated software procedures. The low temperatures required to freeze the hydrogen isotopes contained in a target is provided by a cryogenic cold chamber capable of attaining 15 K. A new method for target manipulation and positioning is studied that employs molecular gas beams to levitate a target and an electrostatic quadrupole structure to provide for its lateral containment. Since the electrostatic target-positioning scheme requires that the targets be charged, preliminary investigation has been carried out for a target-charging mechanism based on ion-bombardment.

  1. Solid Deuterium-Tritium Surface Roughness In A Beryllium Inertial Confinement Fusion Shell

    SciTech Connect

    Kozioziemski, B J; Sater, J D; Moody, J D; Montgomery, D S; Gautier, C

    2006-04-19

    Solid deuterium-tritium (D-T) fuel layers for inertial confinement fusion experiments were formed inside of a 2 mm diameter beryllium shell and were characterized using phase-contrast enhanced x-ray imaging. The solid D-T surface roughness is found to be 0.4 {micro}m for modes 7-128 at 1.5 K below the melting temperature. The layer roughness is found to increase with decreasing temperature, in agreement with previous visible light characterization studies. However, phase-contrast enhanced x-ray imaging provides a more robust surface roughness measurement than visible light methods. The new x-ray imaging results demonstrate clearly that the surface roughness decreases with time for solid D-T layers held at 1.5 K below the melting temperature.

  2. Quantitative Characterization of Inertial Confinement Fusion Capsules Using Phase Contrast Enhanced X-Ray Imaging

    SciTech Connect

    Kozioziemski, B J; Koch, J A; Barty, A; Martz, H E; Lee, W; Fezzaa, K

    2004-05-07

    Current designs for inertial confinement fusion capsules for the National Ignition Facility (NIF) consist of a solid deuterium-tritium (D-T) fuel layer inside of a copper doped beryllium capsule. Phase contrast enhanced x-ray imaging is shown to render the D-T layer visible inside the Be(Cu) capsule. Phase contrast imaging is experimentally demonstrated for several surrogate capsules and validates computational models. Polyimide and low density divinyl benzene foam capsules were imaged at the Advanced Photon Source synchrotron. The surrogates demonstrate that phase contrast enhanced imaging provides a method to characterize surfaces when absorption imaging cannot be used. Our computational models demonstrate that a rough surface can be accurately reproduced in phase contrast enhanced x-ray images.

  3. Advances in compact proton spectrometers for inertial-confinement fusion and plasma nuclear science.

    PubMed

    Seguin, F H; Sinenian, N; Rosenberg, M; Zylstra, A; Manuel, M J-E; Sio, H; Waugh, C; Rinderknecht, H G; Johnson, M Gatu; Frenje, J; Li, C K; Petrasso, R; Sangster, T C; Roberts, S

    2012-10-01

    Compact wedge-range-filter proton spectrometers cover proton energies ∼3-20 MeV. They have been used at the OMEGA laser facility for more than a decade for measuring spectra of primary D(3)He protons in D(3)He implosions, secondary D(3)He protons in DD implosions, and ablator protons in DT implosions; they are now being used also at the National Ignition Facility. The spectra are used to determine proton yields, shell areal density at shock-bang time and compression-bang time, fuel areal density, and implosion symmetry. There have been changes in fabrication and in analysis algorithms, resulting in a wider energy range, better accuracy and precision, and better robustness for survivability with indirect-drive inertial-confinement-fusion experiments. PMID:23126911

  4. Evidence for stratification of deuterium-tritium fuel in inertial confinement fusion implosions.

    PubMed

    Casey, D T; Frenje, J A; Johnson, M Gatu; Manuel, M J-E; Rinderknecht, H G; Sinenian, N; Séguin, F H; Li, C K; Petrasso, R D; Radha, P B; Delettrez, J A; Glebov, V Yu; Meyerhofer, D D; Sangster, T C; McNabb, D P; Amendt, P A; Boyd, R N; Rygg, J R; Herrmann, H W; Kim, Y H; Bacher, A D

    2012-02-17

    Measurements of the D(d,p)T (dd) and T(t,2n)(4)He (tt) reaction yields have been compared with those of the D(t,n)(4)He (dt) reaction yield, using deuterium-tritium gas-filled inertial confinement fusion capsule implosions. In these experiments, carried out on the OMEGA laser, absolute spectral measurements of dd protons and tt neutrons were obtained. From these measurements, it was concluded that the dd yield is anomalously low and the tt yield is anomalously high relative to the dt yield, an observation that we conjecture to be caused by a stratification of the fuel in the implosion core. This effect may be present in ignition experiments planned on the National Ignition Facility. PMID:22401216

  5. Diagnostic for determining the mix in inertial confinement fusion capsule hotspot

    NASA Astrophysics Data System (ADS)

    He, Shibei; Ding, Yongkun; Miao, Wenyong; Zhang, Xing; Tu, Shaoyong; Yuan, Yongteng; Pu, Yudong; Yan, Ji; Wei, Minxi; Yin, Chuansheng

    2016-07-01

    A diagnostic is developed for determining the hotspot mix in inertial confinement fusion experiments. A multi-channel pinhole camera measures Bremsstrahlung emissions from implosion capsules ranging from 6 keV to 30 keV and records an image of the hotspot. Meanwhile, a planar crystal spectrometer measures Ar line emissions used to deduce the electron density of the hotspot. An X-ray streaked camera records the burn duration. With the Bremsstrahlung spectrum, electron density, hotspot volume, and burn duration, the mix quantity is determined by solving a pair of linear equations. This inferred mix amount has an uncertainty due to the uncertainty of the electron density, but with the help of the measured neutron product, the most likely mix quantity value can be determined. This technique is applied to experimental images to infer the quantity of CH ablator mix into the hotspot.

  6. Limitation on Prepulse Level for Cone-Guided Fast-Ignition Inertial Confinement Fusion

    SciTech Connect

    MacPhee, A. G.; Divol, L.; Kemp, A. J.; Chen, C. D.; Chen, H.; Hey, D. S.; Henesian, M.; Key, M. H.; Le Pape, S.; Mackinnon, A. J.; Patel, P. K.; Phillips, T. W.; Tabak, M.; Town, R.; Wilks, S. C.; Akli, K. U.; Stephens, R. B.; Beg, F. N.; Wei, M. S.; Fedosejevs, R. J.

    2010-02-05

    The viability of fast-ignition (FI) inertial confinement fusion hinges on the efficient transfer of laser energy to the compressed fuel via multi-MeV electrons. Preformed plasma due to the laser prepulse strongly influences ultraintense laser plasma interactions and hot electron generation in the hollow cone of an FI target. We induced a prepulse and consequent preplasma in copper cone targets and measured the energy deposition zone of the main pulse by imaging the emitted K{sub {alpha}} radiation. Simulation of the radiation hydrodynamics of the preplasma and particle in cell modeling of the main pulse interaction agree well with the measured deposition zones and provide an insight into the energy deposition mechanism and electron distribution. It was demonstrated that a under these conditions a 100 mJ prepulse eliminates the forward going component of {approx}2-4 MeV electrons.

  7. Implosion dynamics measurements by monochromatic x-ray radiography in inertial confinement fusion

    SciTech Connect

    Chen, Bolun Yang, Zhenghua; Wei, Minxi; Pu, Yudong; Hu, Xin; Chen, Tao; Liu, Shenye; Yan, Ji; Huang, Tianxuan; Jiang, Shaoen; Ding, Yongkun

    2014-12-15

    The implosion dynamics is the most important metrics for assessing the progress toward ignition of an inertially confined fusion experiment. A high spatial resolution monochromatic x-ray imaging system based on the spherically bent crystal is developed to measure the implosion trajectory. The density distribution of the imploding capsules can be inferred with more accurately from monochromatic trajectories. The self emission of the imploded core will be restrained by spectral resolution and the setup of the imaging system. Also the variations of the backlighters' intensity will not be seen in the images. It has been demonstrated on SGII laser facility at the first time. The ablator remaining mass and the implosion velocity, which are the important ablator parameters, are calculated from the monochromatic trajectories. And the results are contrasted to the 1D hydrodynamics simulations.

  8. An improved deconvolution method for X-ray coded imaging in inertial confinement fusion

    NASA Astrophysics Data System (ADS)

    Zhao, Zong-Qing; He, Wei-Hua; Wang, Jian; Hao, Yi-Dan; Cao, Lei-Feng; Gu, Yu-Qiu; Zhang, Bao-Han

    2013-10-01

    In inertial confinement fusion (ICF), X-ray coded imaging is considered as the most potential means to diagnose the compressed core. The traditional Richardson—Lucy (RL) method has a strong ability to deblur the image where the noise follows the Poisson distribution. However, it always suffers from over-fitting and noise amplification, especially when the signal-to-noise ratio of image is relatively low. In this paper, we propose an improved deconvolution method for X-ray coded imaging. We model the image data as a set of independent Gaussian distributions and derive the iterative solution with a maximum-likelihood scheme. The experimental results on X-ray coded imaging data demonstrate that this method is superior to the RL method in terms of anti-overfitting and noise suppression.

  9. Implosion dynamics measurements by monochromatic x-ray radiography in inertial confinement fusion

    NASA Astrophysics Data System (ADS)

    Chen, Bolun; Yang, Zhenghua; Wei, Minxi; Pu, Yudong; Hu, Xin; Chen, Tao; Liu, Shenye; Yan, Ji; Huang, Tianxuan; Jiang, Shaoen; Ding, Yongkun

    2014-12-01

    The implosion dynamics is the most important metrics for assessing the progress toward ignition of an inertially confined fusion experiment. A high spatial resolution monochromatic x-ray imaging system based on the spherically bent crystal is developed to measure the implosion trajectory. The density distribution of the imploding capsules can be inferred with more accurately from monochromatic trajectories. The self emission of the imploded core will be restrained by spectral resolution and the setup of the imaging system. Also the variations of the backlighters' intensity will not be seen in the images. It has been demonstrated on SGII laser facility at the first time. The ablator remaining mass and the implosion velocity, which are the important ablator parameters, are calculated from the monochromatic trajectories. And the results are contrasted to the 1D hydrodynamics simulations.

  10. Interactive tools designed to study mix in inertial confinement fusion implosions

    NASA Astrophysics Data System (ADS)

    Welser-Sherrill, L.; Cooley, J. H.; Wilson, D. C.

    2009-06-01

    Graphical user interface tools have been built in IDL to study mix in inertial confinement fusion (ICF) implosion cores. FLAME, a code which investigates yield degradation due to mix, was designed to post-process 1D hydrodynamic simulation output by implementing a variety of mix models. Three of these mix models are based on the physics of the fall-line. In addition, mixing data from other sources can be incorporated into the yield degradation analysis. Two independent tools called HAME and YAME were developed to calculate the spatial extent of the mix region according to the Haan saturation model and Youngs' phenomenological model, respectively. FLAME facilitates a direct comparison to experimental data. The FLAME, HAME, and YAME interfaces are user-friendly, flexible, and platform-independent.

  11. Transport vehicle for manned Mars missions powered by inertial confinement fusion

    SciTech Connect

    Orth, C.D.; Klein, G.; Sercel, J.; Hoffman, N.; Murray, K.; Chang-Diaz, F.

    1987-06-26

    Inertial confinement fusion (ICF) is an ideal engine power source for manned spacecraft to Mars because of its inherently high power-to-mass ratios and high specific impulses. We have produced a concept for a vehicle powered by ICF and utilizing a magnetic thrust chamber to avoid plasma thermalization with wall structures and the resultant degradation of specific impulse that are unavoidable with the use of mechanical thrust chambers. This vehicle is capable of 100-day manned Mars missions with a 100-metric-ton payload and a total vehicle launch mass near 6000 metric tons, based on advanced technology assumed to be available by A.D. 2020. Such short-duration missions minimize radiation exposures and physiological deterioration of astronauts.

  12. A Freon-Filled Bubble Chamber for Neutron Detection in Inertial Confinement Fusion Experiments

    SciTech Connect

    Ghilea, M.C.; Meyerhofer, D.D.; Sangster, T.C.

    2011-03-24

    Neutron imaging is one of the main methods used in inertial confinement fusion experiments to measure the core symmetry of target implosions. Previous studies have shown that bubble chambers have the potential to obtain higher resolution images of the targets for a shorter source-to-target distance than typical scintillator arrays. A bubble chamber for neutron imaging with Freon 115 as the active medium was designed and built for the OMEGA laser system. Bubbles resulting from spontaneous nucleation were recorded. Bubbles resulting from neutron–Freon interactions were observed at neutron yields of 1013 emitted from deuterium–tritium target implosions on OMEGA. The measured column bubble density was too low for neutron imaging on OMEGA but agreed with the model of bubble formation. The recorded data suggest that neutron bubble detectors are a promising technology for the higher neutron yields expected at National Ignition Facility.

  13. A Freon-filled bubble chamber for neutron detection in inertial confinement fusion experiments

    SciTech Connect

    Ghilea, M. C.; Meyerhofer, D. D.; Sangster, T. C.

    2011-03-15

    Neutron imaging is one of the main methods used in inertial confinement fusion experiments to measure the core symmetry of target implosions. Previous studies have shown that bubble chambers have the potential to obtain higher resolution images of the targets for a shorter source-to-target distance than typical scintillator arrays. A bubble chamber for neutron imaging with Freon 115 as the active medium was designed and built for the OMEGA laser system. Bubbles resulting from spontaneous nucleation were recorded. Bubbles resulting from neutron-Freon interactions were observed at neutron yields of 10{sup 13} emitted from deuterium-tritium target implosions on OMEGA. The measured column bubble density was too low for neutron imaging on OMEGA but agreed with the model of bubble formation. The recorded data suggest that neutron bubble detectors are a promising technology for the higher neutron yields expected at National Ignition Facility.

  14. Compact Intense Neutron Generators Based on Inertial Electrostatic Confinement of D-D Fusion Plasmas

    NASA Astrophysics Data System (ADS)

    Masuda, K.; Inoue, K.; Kajiwara, T.; Nakamatsu, R.

    2015-10-01

    A neutron generator based on inertial electrostatic confinement (IEC) of fusion plasmas is being developed for a non-destructive inspection system of special nuclear materials hidden in sea containers. The new IEC device is equipped with a multistage feedthrough which was designed aiming at both capability of a high bias voltage and enhancement of ion recirculation by modification of electric fields in the IEC device. Experimental comparison was made with a conventional single-stage IEC device developed in an earlier work. As the results, both the increase in the applied voltage and the modified field symmetry by the new multistage scheme showed significant enhancement in the neutron output. As a consequence, neutron output per input discharge current was enhanced drastically by a factor of ~30 in total. Also, the first pulsing experiments of the newly developed IEC neutron generator showed pulsed neutron output with a rapid pulse fall-off of ~ 1 μsec successfully.

  15. Onset of hydrodynamic mix in high-velocity, highly compressed inertial confinement fusion implosions.

    PubMed

    Ma, T; Patel, P K; Izumi, N; Springer, P T; Key, M H; Atherton, L J; Benedetti, L R; Bradley, D K; Callahan, D A; Celliers, P M; Cerjan, C J; Clark, D S; Dewald, E L; Dixit, S N; Döppner, T; Edgell, D H; Epstein, R; Glenn, S; Grim, G; Haan, S W; Hammel, B A; Hicks, D; Hsing, W W; Jones, O S; Khan, S F; Kilkenny, J D; Kline, J L; Kyrala, G A; Landen, O L; Le Pape, S; MacGowan, B J; Mackinnon, A J; MacPhee, A G; Meezan, N B; Moody, J D; Pak, A; Parham, T; Park, H-S; Ralph, J E; Regan, S P; Remington, B A; Robey, H F; Ross, J S; Spears, B K; Smalyuk, V; Suter, L J; Tommasini, R; Town, R P; Weber, S V; Lindl, J D; Edwards, M J; Glenzer, S H; Moses, E I

    2013-08-23

    Deuterium-tritium inertial confinement fusion implosion experiments on the National Ignition Facility have demonstrated yields ranging from 0.8 to 7×10(14), and record fuel areal densities of 0.7 to 1.3 g/cm2. These implosions use hohlraums irradiated with shaped laser pulses of 1.5-1.9 MJ energy. The laser peak power and duration at peak power were varied, as were the capsule ablator dopant concentrations and shell thicknesses. We quantify the level of hydrodynamic instability mix of the ablator into the hot spot from the measured elevated absolute x-ray emission of the hot spot. We observe that DT neutron yield and ion temperature decrease abruptly as the hot spot mix mass increases above several hundred ng. The comparison with radiation-hydrodynamic modeling indicates that low mode asymmetries and increased ablator surface perturbations may be responsible for the current performance. PMID:24010449

  16. Thin shell, high velocity inertial confinement fusion implosions on the national ignition facility.

    PubMed

    Ma, T; Hurricane, O A; Callahan, D A; Barrios, M A; Casey, D T; Dewald, E L; Dittrich, T R; Döppner, T; Haan, S W; Hinkel, D E; Berzak Hopkins, L F; Le Pape, S; MacPhee, A G; Pak, A; Park, H-S; Patel, P K; Remington, B A; Robey, H F; Salmonson, J D; Springer, P T; Tommasini, R; Benedetti, L R; Bionta, R; Bond, E; Bradley, D K; Caggiano, J; Celliers, P; Cerjan, C J; Church, J A; Dixit, S; Dylla-Spears, R; Edgell, D; Edwards, M J; Field, J; Fittinghoff, D N; Frenje, J A; Gatu Johnson, M; Grim, G; Guler, N; Hatarik, R; Herrmann, H W; Hsing, W W; Izumi, N; Jones, O S; Khan, S F; Kilkenny, J D; Knauer, J; Kohut, T; Kozioziemski, B; Kritcher, A; Kyrala, G; Landen, O L; MacGowan, B J; Mackinnon, A J; Meezan, N B; Merrill, F E; Moody, J D; Nagel, S R; Nikroo, A; Parham, T; Ralph, J E; Rosen, M D; Rygg, J R; Sater, J; Sayre, D; Schneider, M B; Shaughnessy, D; Spears, B K; Town, R P J; Volegov, P L; Wan, A; Widmann, K; Wilde, C H; Yeamans, C

    2015-04-10

    Experiments have recently been conducted at the National Ignition Facility utilizing inertial confinement fusion capsule ablators that are 175 and 165  μm in thickness, 10% and 15% thinner, respectively, than the nominal thickness capsule used throughout the high foot and most of the National Ignition Campaign. These three-shock, high-adiabat, high-foot implosions have demonstrated good performance, with higher velocity and better symmetry control at lower laser powers and energies than their nominal thickness ablator counterparts. Little to no hydrodynamic mix into the DT hot spot has been observed despite the higher velocities and reduced depth for possible instability feedthrough. Early results have shown good repeatability, with up to 1/2 the neutron yield coming from α-particle self-heating. PMID:25910132

  17. Hot-spot mix in ignition-scale inertial confinement fusion targets.

    PubMed

    Regan, S P; Epstein, R; Hammel, B A; Suter, L J; Scott, H A; Barrios, M A; Bradley, D K; Callahan, D A; Cerjan, C; Collins, G W; Dixit, S N; Döppner, T; Edwards, M J; Farley, D R; Fournier, K B; Glenn, S; Glenzer, S H; Golovkin, I E; Haan, S W; Hamza, A; Hicks, D G; Izumi, N; Jones, O S; Kilkenny, J D; Kline, J L; Kyrala, G A; Landen, O L; Ma, T; MacFarlane, J J; MacKinnon, A J; Mancini, R C; McCrory, R L; Meezan, N B; Meyerhofer, D D; Nikroo, A; Park, H-S; Ralph, J; Remington, B A; Sangster, T C; Smalyuk, V A; Springer, P T; Town, R P J

    2013-07-26

    Mixing of plastic ablator material, doped with Cu and Ge dopants, deep into the hot spot of ignition-scale inertial confinement fusion implosions by hydrodynamic instabilities is diagnosed with x-ray spectroscopy on the National Ignition Facility. The amount of hot-spot mix mass is determined from the absolute brightness of the emergent Cu and Ge K-shell emission. The Cu and Ge dopants placed at different radial locations in the plastic ablator show the ablation-front hydrodynamic instability is primarily responsible for hot-spot mix. Low neutron yields and hot-spot mix mass between 34(-13,+50)  ng and 4000(-2970,+17 160)  ng are observed. PMID:23931375

  18. Equations of State for Ablator Materials in Inertial Confinement Fusion Simulations

    NASA Astrophysics Data System (ADS)

    Sterne, P. A.; Benedict, L. X.; Hamel, S.; Correa, A. A.; Milovich, J. L.; Marinak, M. M.; Celliers, P. M.; Fratanduono, D. E.

    2016-05-01

    We discuss the development of the tabular equation of state (EOS) models for ablator materials in current use at Lawrence Livermore National Laboratory in simulations of inertial confinement fusion (ICF) experiments at the National Ignition Facility. We illustrate the methods with a review of current models for ablator materials and discuss some of the challenges in performing hydrocode simulations with high-fidelity multiphase models. We stress the importance of experimental data, as well as the utility of ab initio electronic structure calculations, in regions where data is not currently available. We illustrate why Hugoniot data alone is not sufficient to constrain the EOS models. These cases illustrate the importance of experimental EOS data in multi-megabar regimes, and the vital role they play in the development and validation of EOS models for ICF simulations.

  19. A technique for thick polymer coating of inertial-confinement-fusion targets

    NASA Technical Reports Server (NTRS)

    Lee, M. C.; Feng, I.-A.; Wang, T. G.; Kim, H.-G.

    1983-01-01

    A technique to coat a stalk-mounted inertial-confinement fusion (ICF) target with a thick polymer layer has been successfully demonstrated. The polymer solution is first atomized, allowed to coalesce into a droplet, and positioned in a stable acoustic levitating field. The stalk-mounted ICF target is then moved into the acoustic field by manipulating a 3-D positioner to penetrate the surface membrane of the droplet, thus immersing the target in the levitated coating solution. The target inside the droplet is maintained at the center of the levitated liquid using the 3-D positional information provided by two orthogonally placed TV cameras until the drying process is completed. The basic components of the experimental apparatus, including an acoustic levitator, liquid sample deployment device, image acquisition instrumentation, and 3-D positioner, are briefly described.

  20. Models and analyses for inertial-confinement fusion-reactor studies

    SciTech Connect

    Bohachevsky, I.O.

    1981-05-01

    This report describes models and analyses devised at Los Alamos National Laboratory to determine the technical characteristics of different inertial confinement fusion (ICF) reactor elements required for component integration into a functional unit. We emphasize the generic properties of the different elements rather than specific designs. The topics discussed are general ICF reactor design considerations; reactor cavity phenomena, including the restoration of interpulse ambient conditions; first-wall temperature increases and material losses; reactor neutronics and hydrodynamic blanket response to neutron energy deposition; and analyses of loads and stresses in the reactor vessel walls, including remarks about the generation and propagation of very short wavelength stress waves. A discussion of analytic approaches useful in integrations and optimizations of ICF reactor systems concludes the report.

  1. Thin Shell, High Velocity Inertial Confinement Fusion Implosions on the National Ignition Facility

    NASA Astrophysics Data System (ADS)

    Ma, T.; Hurricane, O. A.; Callahan, D. A.; Barrios, M. A.; Casey, D. T.; Dewald, E. L.; Dittrich, T. R.; Döppner, T.; Haan, S. W.; Hinkel, D. E.; Berzak Hopkins, L. F.; Le Pape, S.; MacPhee, A. G.; Pak, A.; Park, H.-S.; Patel, P. K.; Remington, B. A.; Robey, H. F.; Salmonson, J. D.; Springer, P. T.; Tommasini, R.; Benedetti, L. R.; Bionta, R.; Bond, E.; Bradley, D. K.; Caggiano, J.; Celliers, P.; Cerjan, C. J.; Church, J. A.; Dixit, S.; Dylla-Spears, R.; Edgell, D.; Edwards, M. J.; Field, J.; Fittinghoff, D. N.; Frenje, J. A.; Gatu Johnson, M.; Grim, G.; Guler, N.; Hatarik, R.; Herrmann, H. W.; Hsing, W. W.; Izumi, N.; Jones, O. S.; Khan, S. F.; Kilkenny, J. D.; Knauer, J.; Kohut, T.; Kozioziemski, B.; Kritcher, A.; Kyrala, G.; Landen, O. L.; MacGowan, B. J.; Mackinnon, A. J.; Meezan, N. B.; Merrill, F. E.; Moody, J. D.; Nagel, S. R.; Nikroo, A.; Parham, T.; Ralph, J. E.; Rosen, M. D.; Rygg, J. R.; Sater, J.; Sayre, D.; Schneider, M. B.; Shaughnessy, D.; Spears, B. K.; Town, R. P. J.; Volegov, P. L.; Wan, A.; Widmann, K.; Wilde, C. H.; Yeamans, C.

    2015-04-01

    Experiments have recently been conducted at the National Ignition Facility utilizing inertial confinement fusion capsule ablators that are 175 and 165 μ m in thickness, 10% and 15% thinner, respectively, than the nominal thickness capsule used throughout the high foot and most of the National Ignition Campaign. These three-shock, high-adiabat, high-foot implosions have demonstrated good performance, with higher velocity and better symmetry control at lower laser powers and energies than their nominal thickness ablator counterparts. Little to no hydrodynamic mix into the DT hot spot has been observed despite the higher velocities and reduced depth for possible instability feedthrough. Early results have shown good repeatability, with up to 1 /2 the neutron yield coming from α -particle self-heating.

  2. Inhibition of turbulence in inertial-confinement-fusion hot spots by viscous dissipation

    NASA Astrophysics Data System (ADS)

    Weber, C. R.; Clark, D. S.; Cook, A. W.; Busby, L. E.; Robey, H. F.

    2014-05-01

    Achieving ignition in inertial confinement fusion (ICF) requires the formation of a high-temperature (>10 keV) central hot spot. Turbulence has been suggested as a mechanism for degrading the hot-spot conditions by altering transport properties, introducing colder, mixed material, or reducing the conversion of radially directed kinetic energy to hot-spot heating. We show, however, that the hot spot is very viscous, and the assumption of turbulent conditions in the hot spot is incorrect. This work presents the first high-resolution, three-dimensional simulations of National Ignition Facility (NIF) implosion experiments using detailed knowledge of implosion dynamics and instability seeds and including an accurate model of physical viscosity. We find that when viscous effects are neglected, the hot spot can exhibit a turbulent kinetic energy cascade. Viscous effects, however, are significant and strongly damp small-scale velocity structures, with a hot-spot Reynolds number in the range of only 10--100.

  3. Interactive tools designed to study mix in inertial confinement fusion implosions

    SciTech Connect

    Welser-sherrill, Leslie; Cooley, James H; Wilson, Doug C

    2008-01-01

    Graphical user interface tools have been built in IDL to study mix in inertial confinement fusion (ICF) implosion cores. FLAME (Fall-Line Analysis Mix Evaluator), a code which investigates yield degradation due to mix , was designed to post-process 1D hydrodynamic simulation output by implementing a variety of mix models. Three of these mix models are based on the physics of the fall-line. In addition, mixing data from other sources can be incorporated into the yield degradation analysis. Two independent tools called HAME (Haan Analysis Mix Evaluator) and YAME (Youngs Analysis Mix Evaluator) were developed to calculate the spatial extent of the mix region according to the Haan saturation model and Youngs' phenomenological model, respectively. FLAME facilitates a direct comparison to experimental data. The FLAME, HAME, and YAME interfaces are user-friendly, flexible, and platform-independent.

  4. Study on optimal inertial-confinement-fusion hohlraum wall radial density and wall loss

    SciTech Connect

    Zhang Lu; Wu Shunchao; Ding Yongkun; Yang Jiamin; Jiang Shaoen

    2011-03-15

    Reducing hohlraum wall loss is one of the most important ways to improve hohlraum coupling efficiency in laser indirect drive inertial-confinement fusion. It is appeared that a high Z metallic foam as hohlraum wall material will reduce wall loss. By adjusting initial hohlraum wall density distribution along radial axes to {rho}{sub 0}(r)=kr, the numerical simulation results show that it can indeed bring best savings of {approx}40% general wall loss. We conclude that absorbed energy mainly decreases by restraining rarefactions, and a proper slope k can optimize internal energy loss of low density and increased kinetic loss by subsonic. Also saved energy ratio reduces with source temperature decreasing. This approach would cut the reactor driver that needs quite substantially if experiments demonstrate it.

  5. Advances in compact proton spectrometers for inertial-confinement fusion and plasma nuclear science

    SciTech Connect

    Seguin, F. H.; Sinenian, N.; Rosenberg, M.; Zylstra, A.; Manuel, M. J.-E.; Sio, H.; Waugh, C.; Rinderknecht, H. G.; Johnson, M. Gatu; Frenje, J.; Li, C. K.; Petrasso, R.; Sangster, T. C.; Roberts, S.

    2012-10-15

    Compact wedge-range-filter proton spectrometers cover proton energies {approx}3-20 MeV. They have been used at the OMEGA laser facility for more than a decade for measuring spectra of primary D{sup 3}He protons in D{sup 3}He implosions, secondary D{sup 3}He protons in DD implosions, and ablator protons in DT implosions; they are now being used also at the National Ignition Facility. The spectra are used to determine proton yields, shell areal density at shock-bang time and compression-bang time, fuel areal density, and implosion symmetry. There have been changes in fabrication and in analysis algorithms, resulting in a wider energy range, better accuracy and precision, and better robustness for survivability with indirect-drive inertial-confinement-fusion experiments.

  6. Development of aerogel-lined targets for inertial confinement fusion experiments

    SciTech Connect

    Braun, Tom

    2013-03-28

    This thesis explores the formation of ICF compatible foam layers inside of an ablator shell used for inertial confinement fusion experiments at the National Ignition Facility. In particular, the capability of p- DCPD polymer aerogels to serve as a scaffold for the deuterium-tritium mix was analyzed. Four different factors were evaluated: the dependency of different factors such as thickness or composition of a precursor solution on the uniformity of the aerogel layer, how to bring the optimal composition inside of the ablator shell, the mechanical stability of ultra-low density p-DCPD aerogel bulk pieces during wetting and freezing with hydrogen, and the wetting behavior of thin polymer foam layers in HDC carbon ablator shells with liquid deuterium. The research for thesis was done at Lawrence Livermore National Laboratory in cooperation with the Technical University Munich.

  7. Studies of Plastic-Ablator Compressibility for Direct-Drive Inertial Confinement Fusion on Omega

    SciTech Connect

    Hu, S. X.; Smalyuk, V. A.; Goncharov, V. N.; Knauer, J. P.; Radha, P. B.; Igumenshchev, I. V.; Marozas, J. A.; Stoeckl, C.; Yaakobi, B.; Shvarts, D.; Sangster, T. C.; McKenty, P. W.; Meyerhofer, D. D.; Skupsky, S.; McCrory, R. L.

    2008-05-09

    The compression of planar plastic targets was studied with x-ray radiography in the range of laser intensities of I{approx}0.5 to 1.5x10{sup 15} W/cm{sup 2} using square (low-compression) and shaped (high-compression) pulses. Two-dimensional simulations with the radiative hydrocode DRACO show good agreement with measurements at laser intensities up to I{approx}10{sup 15} W/cm{sup 2}. These results provide the first experimental evidence for low-entropy, adiabatic compression of plastic shells in the laser intensity regime relevant to direct-drive inertial confinement fusion. A density reduction near the end of the drive at a high intensity of I{approx}1.5x10{sup 15} W/cm{sup 2} has been correlated with the hard x-ray signal caused by hot electrons from two-plasmon-decay instability.

  8. Studies of Plastic-Ablator Compresibility for Direct-Drive Inertial Confinement Fusion on OMEGA

    SciTech Connect

    Hu, S.X.; Smalyuk, V.A.; Goncharov, V.N.; Knauer, J.P.; Radha, P.B.; Igumenshchev, I.V.; Marozas, J.A.; Stoeckl, C.; Yaakobi, B.; Shvarts, D.; Sangster, T.C.; McKenty, P.W.; Meyerhofer, D.D.; Skupsky, S.; McCrory, R.L.

    2008-05-07

    The compression of planar plastic targets was studied with x-ray radiography in the range of laser intensities of I ~ 0.5 to 1.5 x 10^15 W/cm^2 using square (low-compression) and shaped (high-compression) pulses. Two-dimensional simulations with the radiative hydrocode DRACO show good agreement with measurements at laser intensities up to I ~ 10^15 W/cm^2. These resulsts provide the first experimental evidence for low-entropy, adiabatic compression of plastic shells in the laser intensity regime relevant to direct-drive inertial confinement fusion. A density reduction near the end of the drive at a high intensity of I ~ 1.5 x 10^15 W/cm^2 has been correlated with the hard x-ray signal caused by hot electrons from two-plasmon-decay instability.

  9. A highly efficient neutron time-of-flight detector for inertial confinement fusion experiments

    NASA Astrophysics Data System (ADS)

    Izumi, N.; Yamaguchi, K.; Yamagajo, T.; Nakano, T.; Kasai, T.; Urano, T.; Azechi, H.; Nakai, S.; Iida, T.

    1999-01-01

    We have developed the highly efficient neutron detector system MANDALA for the inertial-confinement-fusion experiment. The MANDALA system consists of 842 elements plastic scintillation detectors and data acquisition electronics. The detection level is the yield of 1.2×105 for 2.5 MeV and 1×105 for 14.1 MeV neutrons (with 100 detected hits). We have calibrated the intrinsic detection efficiencies of the detector elements using a neutron generator facility. Timing calibration and integrity test of the system were also carried out with a 60Co γ ray source. MANDALA system was applied to the implosion experiments at the GEKKO XII laser facility. The integrity test was carried out by implosion experiments.

  10. Thin Shell, High Velocity Inertial Confinement Fusion Implosions on the National Ignition Facility

    SciTech Connect

    Ma, T.; Hurricane, O. A.; Callahan, D. A.; Barrios, M. A.; Casey, D. T.; Dewald, E. L.; Dittrich, T. R.; Doppner, T.; Haan, S. W.; Hinkel, D. E.; Berzak Hopkins, L. F.; Le Pape, S.; MacPhee, A. G.; Pak, A.; Park, H. S.; Patel, P. K.; Remington, B. A.; Robey, H. F.; Salmonson, J. D.; Springer, P. T.; Tommasini, R.; Benedetti, L. R.; Bionta, R.; Bond, E.; Bradley, D. K.; Caggiano, J.; Celliers, P.; Cerjan, C. J.; Church, J. A.; Dixit, S.; Dylla-Spears, R.; Edgell, D.; Edwards, M. J.; Field, J.; Fittinghoff, D. N.; Frenje, J. A.; Gatu Johnson, M.; Grim, G.; Guler, N.; Hatarik, R.; Herrmann, H. W.; Hsing, W. W.; Izumi, N.; Jones, O. S.; Khan, S. F.; Kilkenny, J. D.; Knauer, J.; Kohut, T.; Kozioziemski, B.; Kritcher, A.; Kyrala, G.; Landen, O. L.; MacGowan, B. J.; Mackinnon, A. J.; Meezan, N. B.; Merrill, F. E.; Moody, J. D.; Nagel, S. R.; Nikroo, A.; Parham, T.; Ralph, J. E.; Rosen, M. D.; Rygg, J. R.; Sater, J.; Sayre, D.; Schneider, M. B.; Shaughnessy, D.; Spears, B. K.; Town, R.P. J.; Volegov, P. L.; Wan, A.; Widmann, K.; Wilde, C. H.; Yeamans, C.

    2015-04-06

    Experiments have recently been conducted at the National Ignition Facility utilizing inertial confinement fusion capsule ablators that are 175 and 165 μm in thickness, 10% and 15% thinner, respectively, than the nominal thickness capsule used throughout the high foot and most of the National Ignition Campaign. These three-shock, high-adiabat, high-foot implosions have demonstrated good performance, with higher velocity and better symmetry control at lower laser powers and energies than their nominal thickness ablator counterparts. Little to no hydrodynamic mix into the DT hot spot has been observed despite the higher velocities and reduced depth for possible instability feedthrough. Earlier results have shown good repeatability, with up to 1/2 the neutron yield coming from α-particle self-heating.

  11. Stability of the lithium 'waterfall' first wall protection concept for inertial confinement fusion reactors

    SciTech Connect

    Esser, P.D.; Paul, D.D.; Abdel-Khalik, S.I.

    1981-01-01

    Uncertainties regarding the feasibility of using an annular waterfall of liquid lithium to protect the first wall in inertial confinement fusion reactor cavities have prompted a theoretical investigation of annular jet stability. Infinitesimal perturbation techniques are applied to an idealized model of the jet with disturbances acting upon either or both of the free surfaces. Dispersion relations are derived that predict the range of disturbance frequencies leading to instability, as well as the perturbation growth rates and jet break-up length. The results are extended to turbulent annular jets and are evaluated for the lithium waterfall design. It is concluded that inherent instabilities due to turbulent fluctuations will not cause the jet to break up over distances comparable to the height of the reactor cavity.

  12. Stability of the lithium ''WATERFALL'' first wall protection concept for inertial confinement fusion reactors

    SciTech Connect

    Esser, P.D.; Abel-Khalik, S.I.; Paul, D.D.

    1981-04-01

    Uncertainties regarding the feasibility of using an annular ''waterfall'' of liquid lithium to protect the first wall in inertial confinement fusion reactor cavities have prompted a theoretical investigation of annular jet stability. Infinitesimal perturbation techniques are applied to an idealized model of the jet with disturbances acting upon either or both of the free surfaces. Dispersion relations are derived that predict the range of disturbance frequencies leading to instability, as well as the perturbation growth rates and jet breakup length. The results are extended to turbulent annular jets and are evaluated for the lithium waterfall design. It is concluded that inherent instabilities due to turbulent fluctuations will not cause the jet to break up over distances comparable to the height of the reactor cavity.

  13. Review of the magnetic fusion program by the 1986 ERAB Fusion Panel

    NASA Astrophysics Data System (ADS)

    Davidson, Ronald C.

    1987-09-01

    The 1986 ERAB Fusion Panel finds that fusion energy continues to be an attractive energy source with great potential for the future, and that the magnetic fusion program continues to make substantial technical progress. In addition, fusion research advances plasma physics, a sophisticated and useful branch of applied science, as well as technologies important to industry and defense. These factors fully justify the substantial expenditures by the Department of Energy in fusion research and development (R&D). The Panel endorses the overall program direction, strategy, and plans, and recognizes the importance and timeliness of proceeding with a burning plasma experiment, such as the proposed Compact Ignition Tokamak (CIT) experiment.

  14. BOOK REVIEW: Inertial confinement fusion: The quest for ignition and energy gain using indirect drive

    NASA Astrophysics Data System (ADS)

    Yamanaka, C.

    1999-06-01

    Inertial confinement fusion (ICF) is an alternative way to control fusion which is based on scaling down a thermonuclear explosion to a small size, applicable for power production, a kind of thermonuclear internal combustion engine. This book extends many interesting topics concerning the research and development on ICF of the last 25 years. It provides a systematic development of the physics basis and also various experimental data on radiation driven implosion. This is a landmark treatise presented at the right time. It is based on the article ``Development of the indirect-drive approach to inertial confinement fusion and the target physics basis for ignition and gain'' by J.D. Lindl, published in Physics of Plasmas, Vol. 2, November 1995, pp. 3933-4024. As is well known, in the United States of America research on the target physics basis for indirect drive remained largely classified until 1994. The indirect drive approaches were closely related to nuclear weapons research at Lawrence Livermore and Los Alamos National Laboratories. In Japan and other countries, inertial confinement fusion research for civil energy has been successfully performed to achieve DT fuel pellet compression up to 1000 times normal density, and indirect drive concepts, such as the `Cannon Ball' scheme, also prevailed at several international conferences. In these circumstances the international fusion community proposed the Madrid Manifesto in 1988, which urged openness of ICF information to promote international collaboration on civil energy research for the future resources of the human race. This proposal was also supported by some of the US scientists. The United States Department of Energy revised its classification guidelines for ICF six years after the Madrid Manifesto. This first book from the USA treating target physics issues, covering topics from implosion dynamics to hydrodynamic stability, ignition physics, high-gain target design and the scope for energy applications is

  15. Inertial confinement fusion implosions with imposed magnetic field compression using the OMEGA Laser

    SciTech Connect

    Hohenberger, M.; Chang, P.-Y.; Fiksel, G.; Knauer, J. P.; Marshall, F. J.; Betti, R.; Meyerhofer, D. D.; and others

    2012-05-15

    Experiments applying laser-driven magnetic-flux compression to inertial confinement fusion (ICF) targets to enhance the implosion performance are described. Spherical plastic (CH) targets filled with 10 atm of deuterium gas were imploded by the OMEGA Laser, compare Phys. Plasmas 18, 056703 or Phys. Plasmas 18, 056309. Before being imploded, the targets were immersed in an 80-kG magnetic seed field. Upon laser irradiation, the high implosion velocities and ionization of the target fill trapped the magnetic field inside the capsule, and it was amplified to tens of megagauss through flux compression. At such strong magnetic fields, the hot spot inside the spherical target was strongly magnetized, reducing the heat losses through electron confinement. The experimentally observed ion temperature was enhanced by 15%, and the neutron yield was increased by 30%, compared to nonmagnetized implosions [P. Y. Chang et al., Phys. Rev. Lett. 107, 035006 (2011)]. This represents the first experimental verification of performance enhancement resulting from embedding a strong magnetic field into an ICF capsule. Experimental data for the fuel-assembly performance and magnetic field are compared to numerical results from combining the 1-D hydrodynamics code LILAC with a 2-D magnetohydrodynamics postprocessor.

  16. Mode 1 drive asymmetry in inertial confinement fusion implosions on the National Ignition Facility

    SciTech Connect

    Spears, Brian K. Edwards, M. J.; Hatchett, S.; Kritcher, A.; Lindl, J.; Munro, D.; Patel, P.; Robey, H. F.; Town, R. P. J.; Kilkenny, J.; Knauer, J.

    2014-04-15

    Mode 1 radiation drive asymmetry (pole-to-pole imbalance) at significant levels can have a large impact on inertial confinement fusion implosions at the National Ignition Facility (NIF). This asymmetry distorts the cold confining shell and drives a high-speed jet through the hot spot. The perturbed hot spot shows increased residual kinetic energy and reduced internal energy, and it achieves reduced pressure and neutron yield. The altered implosion physics manifests itself in observable diagnostic signatures, especially the neutron spectrum which can be used to measure the neutron-weighted flow velocity, apparent ion temperature, and neutron downscattering. Numerical simulations of implosions with mode 1 asymmetry show that the resultant simulated diagnostic signatures are moved toward the values observed in many NIF experiments. The diagnostic output can also be used to build a set of integrated implosion performance metrics. The metrics indicate that P{sub 1} has a significant impact on implosion performance and must be carefully controlled in NIF implosions.

  17. Neutron Induced D Breakup in Inertial Confinement Fusion at the Omega Laser Facility

    NASA Astrophysics Data System (ADS)

    Forrest, C. J.; Glebov, V. Yu.; Knauer, J. P.; Radha, P. B.; Regan, S. P.; Sangster, T. C.; Stoeckl, C.; Schroder, W. U.; Frenje, J. A.; Gatu Johnson, M.

    2015-11-01

    High-resolution neutron spectroscopy is used to study the deuteron breakup reaction D(n,n ') np in the thermonuclear environment created in inertial confinement fusion experiments at the Omega Laser Facility. Neutrons with an energy of 14.1 MeV generated in the primary D-T fusion reactions scatter elastically and inelastically off the dense (cryogenic) D-T fuel assembly surrounding the central hot spot at peak fuel compression. These neutrons also induce a breakup of the fuel deuterons. The corresponding breakup cross section is measured relative to elastic n -D and n -T scattering, i.e., simultaneously in the same environment. Apart from astrophysical and technological interest, the neutron-induced deuteron breakup reaction is of interest to the physics of nucleon -nucleon forces. For example, theoretical calculations predict a noticeable influence of nucleonic three-body forces on the magnitude of the breakup cross section. Preliminary results from measurements of the neutron contribution in the 2- to 6-MeV range show reasonable agreement with the published ENDL 2008.2 semi-empirical cross-section. This material is based upon work supported by the Department of Energy National Nuclear Security Administration under Award Number DE-NA0001944.

  18. Hydrodynamic Scaling of the Deceleration-Phase Rayleigh-Taylor Instability for Inertial Confinement Fusion Implosions

    NASA Astrophysics Data System (ADS)

    Bose, A.; Betti, R.; Woo, K.; Nora, R.

    2014-10-01

    Hydrodynamic equivalence and ignition theory allow for the extrapolation of OMEGA experiments to ignition-scale implosions. The yield-over-clean (YOC = measured yield/1-D yield) depicts the effect of hydro-instabilities on inertial confinement fusion implosions. A 2-D study of the deceleration-phase Rayleigh-Taylor instability (RTI) is carried out to assess the YOC scaling with target size at varying nonuniformity levels. The deceleration-phase ablative RTI is mitigated by the hot-spot thermal and radiation transport, which do not scale hydro-equivalently. Scaling of the thermal conduction shows that hot-spot ablation velocity is higher on OMEGA than on the National Ignition Facility (NIF), resulting in higher RTI growth factors on the NIF. Radiation emitted in the hot-spot makes the implosion nearly hydro-equivalent by increasing the density gradient scale length on the NIF. Thermal conduction and radiation both are nonscalable physics in the deceleration phase, with complementary impacts the scaling of deceleration-phase RTI. Analytic and numerical study of the deceleration-phase RTI on OMEGA and NIF-scale targets show that YOCNIF ~ YOCΩ considering identical laser imprinting and normalized ice roughness levels. This material is based upon work supported by the Department of Energy National Nuclear Security Administration under Award Number DE-NA0001944 and the Office of Fusion Energy Sciences Number DE-FG02-04ER54786.

  19. Production and Metrology of Cylindrical Inertial Confinement Fusion Targets with Sinusoidal Perturbations

    SciTech Connect

    Balkey, M.M.; Day, R.D.; Batha, S.H.; Elliot, N.E.; Pierce, T.; Sandoval, D.L.; Garrard, K.P.; Sohn, A.

    2004-03-15

    Shock waves generated during inertial confinement fusion implosions propagate toward the center of the capsule encountering interfaces between materials with different densities, such as between the ablator and the DT fuel. These interactions are hydrodynamically unstable and the resulting instability causes mixing of the materials at the interface, which is predicted to have detrimental effects on fusion burn. In this experiment, the growth of a single-mode perturbation machined into a radiographically opaque marker layer, driven by a strong shock, is measured during a cylindrically symmetric implosion. These measurements are used to validate simulations and theories of the complex hydrodynamics. Since any perturbation on the marker layer surface will lead to instability growth, precise knowledge of the initial conditions is critical. The targets used in this experiment have up to a 3.0-{mu}m-amplitude, mode 28 ({lambda} = 98 {mu}m) sinusoidal perturbation machined into a 438-{mu}m-outerradius aluminum band with a nominal thickness of 8 {mu}m. The perturbations were machined using a fast-tool servo [B. JARED and T. A. DOW, Precision Engineering Center Annual Report, North Carolina State University, Raleigh NC, p. 123 (1996)] and were metrologized using a linear variable differential transformer [FRANK J. OLIVER, Practical Instrumentation Tranducers, p. 42-45, Hayden Book Company (1971)]. In this paper, the importance of metrology is discussed and is shown to be critical to the interpretation of experimental results.

  20. Progress in laboratory high gain ICF (inertial confinement fusion): Prospects for the future

    SciTech Connect

    Storm, E.; Lindl, J.D.; Campbell, E.M.; Bernat, T.P.; Coleman, L.W.; Emmett, J.L.; Hogan, W.J.; Hunt, J.T.; Krupke, W.F.; Lowdermilk, W.H.

    1988-01-01

    Inertial confinement fusion (ICF), a thermonuclear reaction in a small (/approximately/5 mm diameter) fuel capsule filled with a few milligrams of deuterium and tritium, has been the subject of very fruitful experimentation since the early 1970's. High gain ICF is now on the threshold of practical applications. With a Laboratory Microfusion Facility (LMF), these applications will have major implications for national defense, basic and applied science, and power production. With a driver capable of delivering about 10 MJ in a 10-ns pulse at an intensity of /approximately/3 /times/ 10/sup 14/ W/cm/sup 2/, an appropriately configured cryogenic capsule could be compressed to a density of about 200 g/cm/sup 3/ and a temperature of 3--5 keV. Under these conditions, up to 10 mg of DT could be ignited, and with a burn efficiency of about 30%, release up to 1000 MJ of fusion energy, an energy gain of about 100. A thousand megajoules is equivalent to about one quarter ton of TNT, or about 7 gallons of oil--an amount of energy tractable under laboratory conditions and potentially very useful for a variety of applications. 61 refs., 33 figs.

  1. Numerical model for simulating the dynamic response of an inertial confinement fusion cavity gas to a target explosion

    SciTech Connect

    McCarville, T.J.

    1982-01-01

    One of the methods suggested for protecting the first wall of an inertial confinement fusion cavity from the x-rays and ions emitted by an exploding target is to fill the cavity with a buffer gas. A computer code package is developed in this thesis for studying the radiative and hydrodynamic response of the gas to an exploding target.

  2. Optimizing Neutron Production Rates from D-D Fusion in an Inertial Electrostatic Confinement Device

    SciTech Connect

    Wehmeyer, A.L.; Radel, R.F.; Kulcinski, G.L.

    2005-05-15

    Detection of explosives has been identified as a near term commercial opportunity for using a fusion plasma. Typical explosive compositions contain low Z material (C, N, O) which are not easily detected using conventional x-rays or metal detectors. However, 2.45 MeV neutrons produced in a D-D fusion reaction can be used for detection of explosives or other clandestine materials in suitcases, packages, or shipping containers.Steady-state D-D operation is possible using an Inertial Electrostatic Confinement (IEC) fusion device. The University of Wisconsin IEC device has produced D-D neutrons at 1.8 x 10{sup 8} neutrons/second at a true cathode voltage of 166 kV and a meter current of 68 mA. These neutron production rates are approaching the levels required for the detection of explosives. In order to increase and optimize the neutron production rate in the IEC device, experiments were performed altering the cathode's size (diameter), geometry, and material composition. Preliminary results indicate that significant differences in neutron production rates are not achieved by altering the geometry or material composition of the cathode. However, the neutron production rate was found to increase approximately 20% by doubling the cathode's diameter from 10 cm to 20 cm. In addition, increasing the cathode voltage from 34 kV to 94 kV at a meter current of 30 mA increased the neutron production rate from 1.24 x 10{sup 6} n/s to 2.83 x 10{sup 7} n/s.

  3. Program status 3. quarter -- FY 1990: Confinement systems programs

    SciTech Connect

    1990-07-24

    Highlights of the DIII-D Research Operations task are: completed five weeks tokamak operations; initiated summer vent; achievement of 10.7% beta; carried out first dimensionless transport scaling experiment; completed IBW program; demonstrated divertor heat reduction with gas puffing; field task proposals presented to OFE; presentation of DIII-D program to FPAC; made presentation to Admiral Watkins; and SAN safety review. Summaries are given on research programs, operations, program development, hardware development, operations support and collaborative efforts. Brief summaries of progress on the International Cooperation task include: TORE SUPRA, ASDEX, JFT-2M, and JET. Funding for work on CIT physics was received this quarter. Several physics R and D planning tasks were initiated. Earlier in FY90, a poloidal field coil shaping system (PFC) was found for DIGNITOR. This quarter more detailed analysis has been done to optimize the design of the PFC system.

  4. Midterm Summary of Japan-US Fusion Cooperation Program TITAN

    SciTech Connect

    Muroga, Takeo; Sze, Dai-Kai; Sokolov, Mikhail; Katoh, Yutai; Stoller, Roger E

    2011-01-01

    Japan-US cooperation program TITAN (Tritium, Irradiation and Thermofluid for America and Nippon) started in April 2007 as 6-year project. This is the summary report at the midterm of the project. Historical overview of the Japan-US cooperation programs and direction of the TITAN project in its second half are presented in addition to the technical highlights. Blankets are component systems whose principal functions are extraction of heat and tritium. Thus it is crucial to clarify the potentiality for controlling heat and tritium flow throughout the first wall, blanket and out-of-vessel recovery systems. The TITAN project continues the JUPITER-II activity but extends its scope including the first wall and the recovery systems with the title of 'Tritium and thermofluid control for magnetic and inertial confinement systems'. The objective of the program is to clarify the mechanisms of tritium and heat transfer throughout the first-wall, the blanket and the heat/tritium recovery systems under specific conditions to fusion such as irradiation, high heat flux, circulation and high magnetic fields. Based on integrated models, the breeding, transfer, inventory of tritium and heat extraction properties will be evaluated for some representative liquid breeder blankets and the necessary database will be obtained for focused research in the future.

  5. Planning for U.S. Fusion Community Participation in the ITER Program

    SciTech Connect

    Baker, Charles; Berk, Herbert; Greenwald, Martin; Mauel, Michael E.; Najmabadi, Farrokh; Nevins, William M.; Stambaugh, Ronald; Synakowski, Edmund; Batchelor, Donald B.; Fonck, Raymond; Hawryluk, Richard J.; Meade, Dale M.; Neilson, George H.; Parker, Ronald; Strait, Ted

    2006-06-07

    A central step in the mission of the U.S. Fusion Energy Sciences program is the creation and study of a fusion-powered "star on earth", where the same energy source that drives the sun and other stars is reproduced and controlled for sustained periods in the laboratory. This “star” is formed by an ionized gas, or plasma, heated to fusion temperatures in a magnetic confinement device known as a tokamak, which is the most advanced magnetic fusion concept. The ITER tokamak is designed to be the premier scientific tool for exploring and testing expectations for plasma behavior in the fusion burning plasma regime, wherein the fusion process itself provides the dominant heat source to sustain the plasma temperature. It will provide the scientific basis and control tools needed to move toward the fusion energy goal. The ITER project confronts the grand challenge of creating and understanding a burning plasma for the first time. The distinguishing characteristic of a burning plasma is the tight coupling between the fusion heating, the resulting energetic particles, and the confinement and stability properties of the plasma. Achieving this strongly coupled burning state requires resolving complex physics issues and integrating challenging technologies. A clear and comprehensive scientific understanding of the burning plasma state is needed to confidently extrapolate plasma behavior and related technology beyond ITER to a fusion power plant. Developing this predictive understanding is the overarching goal of the U.S. Fusion Energy Sciences program. The burning plasma research program in the U.S. is being organized to maximize the scientific benefits of U.S. participation in the international ITER experiment. It is expected that much of the research pursued on ITER will be based on the scientific merit of proposed activities, and it will be necessary to maintain strong fusion research capabilities in the U.S. to successfully contribute to the success of ITER and optimize

  6. The updated advancements of inertial confinement fusion program in China

    NASA Astrophysics Data System (ADS)

    He, X. T.; ICF Teams in China

    2016-03-01

    The recent achievements of ICF research in China are reviewed. The constructions of laser facilities of SG-III and SG-IIUP are completed in this year and the full energy output operation will be in 2014. The target physics studies involving numerical simulations of a new ignition scheme, which is proposed to enhance implosion velocity and suppress hydrodynamic instability and distortion at interface between hot spot and main fuel, and experimental results (a few selected examples) are presented.

  7. Spectroscopic Studies of Atomic and Molecular Processes in the Edge Region of Magnetically Confined Fusion Plasmas

    SciTech Connect

    Hey, J. D.; Brezinsek, S.; Mertens, Ph.; Unterberg, B.

    2006-12-01

    Edge plasma studies are of vital importance for understanding plasma-wall interactions in magnetically confined fusion devices. These interactions determine the transport of neutrals into the plasma, and the properties of the plasma discharge. This presentation deals with optical spectroscopic studies of the plasma boundary, and their role in elucidating the prevailing physical conditions. Recorded spectra are of four types: emission spectra of ions and atoms, produced by electron impact excitation and by charge-exchange recombination, atomic spectra arising from electron impact-induced molecular dissociation and ionisation, visible spectra of molecular hydrogen and its isotopic combinations, and laser-induced fluorescence (LIF) spectra. The atomic spectra are strongly influenced by the confining magnetic field (Zeeman and Paschen-Back effects), which produces characteristic features useful for species identification, temperature determination by Doppler broadening, and studies of chemical and physical sputtering. Detailed analysis of the Zeeman components in both optical and LIF spectra shows that atomic hydrogen is produced in various velocity classes, some related to the relevant molecular Franck-Condon energies. The latter reflect the dominant electron collision processes responsible for production of atoms from molecules. This assignment has been verified by gas-puffing experiments through special test limiters. The higher-energy flanks of hydrogen line profiles probably also show the influence of charge-exchange reactions with molecular ions accelerated in the plasma sheath ('scrape-off layer') separating limiter surfaces from the edge plasma, in analogy to acceleration in the cathode-fall region of gas discharges. While electron collisions play a vital role in generating the spectra, ion collisions with excited atomic radiators act through re-distribution of population among the atomic fine-structure sublevels, and momentum transfer to the atomic nuclei via

  8. Crystallization and fusion behaviors, observed by adiabatic calorimetry, of benzene confined in silica mesopores with uniform diameters.

    PubMed

    Nagoe, Atsushi; Oguni, Masaharu; Fujimori, Hiroki

    2015-03-18

    Heat capacities and spontaneous enthalpy-relaxation effects of the benzene confined in silica MCM-41 and SBA-15 pores with uniform diameters were measured by high-precision adiabatic calorimetry. The fusion temperatures and fusion enthalpies determined were compared with the literature results of benzene confined within pores of CPG glasses. It was confirmed, from the observed spontaneous heat-release or -absorption effects, that there exists a non-crystallizing amorphous component of confined benzene, as reported previously. The pore-diameter dependence of fusion enthalpy observed was inconsistent with the previously proposed model which suggested that the non-crystallizing amorphous component is located on the pore wall in the form of a shell-like structure of a few nm in thickness. A very slow relaxation process corresponding to a translational-diffusion motion of molecule was observed, indicating that the benzene fills the pores incompletely along the pore channel. In addition, we found that the fusion enthalpy as a function of inverse pore-diameter dependence decreases steeply in the range of 60-10 nm in diameter while gradually in the range around 5 nm. PMID:25627639

  9. Crystallization and fusion behaviors, observed by adiabatic calorimetry, of benzene confined in silica mesopores with uniform diameters

    NASA Astrophysics Data System (ADS)

    Nagoe, Atsushi; Oguni, Masaharu; Fujimori, Hiroki

    2015-03-01

    Heat capacities and spontaneous enthalpy-relaxation effects of the benzene confined in silica MCM-41 and SBA-15 pores with uniform diameters were measured by high-precision adiabatic calorimetry. The fusion temperatures and fusion enthalpies determined were compared with the literature results of benzene confined within pores of CPG glasses. It was confirmed, from the observed spontaneous heat-release or -absorption effects, that there exists a non-crystallizing amorphous component of confined benzene, as reported previously. The pore-diameter dependence of fusion enthalpy observed was inconsistent with the previously proposed model which suggested that the non-crystallizing amorphous component is located on the pore wall in the form of a shell-like structure of a few nm in thickness. A very slow relaxation process corresponding to a translational-diffusion motion of molecule was observed, indicating that the benzene fills the pores incompletely along the pore channel. In addition, we found that the fusion enthalpy as a function of inverse pore-diameter dependence decreases steeply in the range of 60-10 nm in diameter while gradually in the range around 5 nm.

  10. Neutron irradiation experiments for fusion reactor materials through JUPITER program

    NASA Astrophysics Data System (ADS)

    Abe, K.; Kohyama, A.; Namba, C.; Wiffen, F. W.; Jones, R. H.

    1998-10-01

    A Japan-USA Program of irradiation experiments for fusion research, "JUPITER", has been established as a 6 year program from 1995 to 2000. The goal is to study "the dynamic behavior of fusion reactor materials and their response to variable and complex irradiation environment". This is phase-three of the collaborative program, which follows RTNS-II Program (Phase-1: 1982-1986) and FFTF/MOTA Program (Phase-2: 1987-1994). This program is to provide a scientific basis for application of materials performance data, generated by fission reactor experiments, to anticipated fusion environments. Following the systematic study on cumulative irradiation effects, done through FFTF/MOTA Program, JUPITER is emphasizing the importance of dynamic irradiation effects on materials performance in fusion systems. The irradiation experiments in this program include low activation structural materials, functional ceramics and other innovative materials. The experimental data are analyzed by theoretical modeling and computer simulation to integrate the above effects.

  11. Dynamic symmetry of indirectly driven inertial confinement fusion capsules on the National Ignition Facilitya)

    NASA Astrophysics Data System (ADS)

    Town, R. P. J.; Bradley, D. K.; Kritcher, A.; Jones, O. S.; Rygg, J. R.; Tommasini, R.; Barrios, M.; Benedetti, L. R.; Berzak Hopkins, L. F.; Celliers, P. M.; Döppner, T.; Dewald, E. L.; Eder, D. C.; Field, J. E.; Glenn, S. M.; Izumi, N.; Haan, S. W.; Khan, S. F.; Kline, J. L.; Kyrala, G. A.; Ma, T.; Milovich, J. L.; Moody, J. D.; Nagel, S. R.; Pak, A.; Peterson, J. L.; Robey, H. F.; Ross, J. S.; Scott, R. H. H.; Spears, B. K.; Edwards, M. J.; Kilkenny, J. D.; Landen, O. L.

    2014-05-01

    In order to achieve ignition using inertial confinement fusion it is important to control the growth of low-mode asymmetries as the capsule is compressed. Understanding the time-dependent evolution of the shape of the hot spot and surrounding fuel layer is crucial to optimizing implosion performance. A design and experimental campaign to examine sources of asymmetry and to quantify symmetry throughout the implosion has been developed and executed on the National Ignition Facility (NIF) [E. I. Moses et al., Phys. Plasmas 16, 041006 (2009)]. We have constructed a large simulation database of asymmetries applied during different time intervals. Analysis of the database has shown the need to measure and control the hot-spot shape, areal density distribution, and symmetry swings during the implosion. The shape of the hot spot during final stagnation is measured using time-resolved imaging of the self-emission, and information on the shape of the fuel at stagnation can be obtained from Compton radiography [R. Tommasini et al., Phys. Plasmas 18, 056309 (2011)]. For the first time on NIF, two-dimensional inflight radiographs of gas-filled and cryogenic fuel layered capsules have been measured to infer the symmetry of the radiation drive on the capsule. These results have been used to modify the hohlraum geometry and the wavelength tuning to improve the inflight implosion symmetry. We have also expanded our shock timing capabilities by the addition of extra mirrors inside the re-entrant cone to allow the simultaneous measurement of shock symmetry in three locations on a single shot, providing asymmetry information up to Legendre mode 4. By diagnosing the shape at nearly every step of the implosion, we estimate that shape has typically reduced fusion yield by about 50% in ignition experiments.

  12. Overview of the VISTA Spacecraft Concept Powered by Inertial Confinement Fusion

    SciTech Connect

    Orth, C D

    2000-11-21

    VISTA was conceived through a detailed systems analysis as a viable, realistic, and defensible spacecraft concept based on advanced ICF technology but existing or near-term technology for other systems. It is a conical self-contained single-stage piloted spacecraft in which a magnetic thrust chamber directs the plasma emissions from inertial confinement fusion (ICF) targets into a rearward exhaust. VISTA's propulsion system is therefore unique because it is based on (1) a rather mature technology (ICF), which is known to work with sufficient driver input; (2) direct heating of all expellant by the fusion process, thus providing high mass flow rates without significant degradation of jet efficiency; and (3) a magnetic thrust chamber, which avoids the plasma thermalization and resultant degradation of specific impulse that are unavoidable with the use of mechanical thrust chambers. VISTA therefore has inherently high power/mass ratios and high specific impulses. With advanced ICF technology, ultra-fast roundtrips (RTs) to objects within the solar system are possible (e.g., {ge}145 days RT to Mars, {ge}7 years RT to Pluto). Such short-duration missions are imperative to minimize the human physiological deteriorations arising from zero gravity and the cosmic-radiation. In addition, VISTA offers on-board artificial gravity and propellant-based shielding from cosmic rays, thus reducing the physiological deteriorations to insignificant levels. In this paper, we give an overview of the various vehicle systems for this concept, estimate the general missions performance capabilities for interplanetary missions, and describe in detail the performance for the baseline mission of a piloted roundtrip to Mars with a 100-ton payload. Items requiring further research include a reduction of the wet mass from its baseline value of 6,000 metric tons, and the development of fast ignition or its equivalent to provide target gains in excess of several hundred. With target gains well

  13. The potential role of electric fields and plasma barodiffusion on the inertial confinement fusion databasea)

    NASA Astrophysics Data System (ADS)

    Amendt, Peter; Wilks, S. C.; Bellei, C.; Li, C. K.; Petrasso, R. D.

    2011-05-01

    The generation of strong, self-generated electric fields (GV/m) in direct-drive, inertial-confinement-fusion (ICF) capsules has been reported [Rygg et al., Science 319, 1223 (2008); Li et al., Phys. Rev. Lett. 100, 225001 (2008)]. A candidate explanation for the origin of these fields based on charge separation across a plasma shock front was recently proposed [Amendt et al., Plasma Phys. Controlled Fusion 51 124048 (2009)]. The question arises whether such electric fields in imploding capsules can have observable consequences on target performance. Two well-known anomalies come to mind: (1) an observed ≈2× greater-than-expected deficit of neutrons in an equimolar D3He fuel mixture compared with hydrodynamically equivalent D [Rygg et al., Phys. Plasmas 13, 052702 (2006)] and DT [Herrmann et al., Phys. Plasmas 16, 056312 (2009)] fuels, and (2) a similar shortfall of neutrons when trace amounts of argon are mixed with D in indirect-drive implosions [Lindl et al., Phys. Plasmas 11, 339 (2004)]. A new mechanism based on barodiffusion (or pressure gradient-driven diffusion) in a plasma is proposed that incorporates the presence of shock-generated electric fields to explain the reported anomalies. For implosions performed at the Omega laser facility [Boehly et al., Opt. Commun. 133, 495 (1997)], the (low Mach number) return shock has an appreciable scale length over which the lighter D ions can diffuse away from fuel center. The depletion of D fuel is estimated and found to lead to a corresponding reduction in neutrons, consistent with the anomalies observed in experiments for both argon-doped D fuels and D3He equimolar mixtures. The reverse diffusional flux of the heavier ions toward fuel center also increases the pressure from a concomitant increase in electron number density, resulting in lower stagnation pressures and larger imploded cores in agreement with gated, self-emission, x-ray imaging data.

  14. Program status. 2nd quarter - FY 1995. Confinement systems programs

    SciTech Connect

    1995-04-18

    We conducted physics experiments: record normalized {Beta} = 4.9 achieved in VH-mode, {Beta} limits of ITER-like configurations evaluated, FWCD commissioning. The tokamak vessel was opened to atmosphere for six weeks and a number of key diagnostics for understanding the divertor were installed. The DIII-D Advisory Committee met in January to review the DIII-D program and plan. They commended us for recent progress and supported the vanadium divertor design. The U.S./Japan DIII-D steering committee met and recommended extending the agreement to the year 2000. The field work proposal for FY 96/97 was presented in Washington on March 29, 1995. A review of the DIII-D plan to install vanadium structural components as part of the new radiative divertor modification was held in Washington 31, 1995 and the panel endorsed the plans. Preliminary plans were developed with PPPL for collaborations in FY96,

  15. The NASA-Lewis program on fusion energy for space power and propulsion, 1958-1978

    NASA Technical Reports Server (NTRS)

    Schulze, Norman R.; Roth, J. Reece

    1990-01-01

    An historical synopsis is provided of the NASA-Lewis research program on fusion energy for space power and propulsion systems. It was initiated to explore the potential applications of fusion energy to space power and propulsion systems. Some fusion related accomplishments and program areas covered include: basic research on the Electric Field Bumpy Torus (EFBT) magnetoelectric fusion containment concept, including identification of its radial transport mechanism and confinement time scaling; operation of the Pilot Rig mirror machine, the first superconducting magnet facility to be used in plasma physics or fusion research; operation of the Superconducting Bumpy Torus magnet facility, first used to generate a toroidal magnetic field; steady state production of neutrons from DD reactions; studies of the direct conversion of plasma enthalpy to thrust by a direct fusion rocket via propellant addition and magnetic nozzles; power and propulsion system studies, including D(3)He power balance, neutron shielding, and refrigeration requirements; and development of large volume, high field superconducting and cryogenic magnet technology.

  16. Applications of deuterium-tritium equation of state based on density functional theory in inertial confinement fusion

    SciTech Connect

    Wang, Cong; He, Xian-Tu; Ye, Wen-Hua; Zhang, Ping; Fan, Zheng-Feng

    2015-06-15

    An accurate equation of state for deuterium-tritium mixture is of crucial importance in inertial confinement fusion. The equation of state can determine the compressibility of the imploding target and the energy deposited into the fusion fuel. In the present work, a new deuterium-tritium equation of state, which is calculated according to quantum molecular dynamic and orbital free molecular dynamic simulations, has been used to study the target implosion hydrodynamics. The results indicate that the peak density predicted by the new equation of state is ∼10% higher than the quotidian equation of state data. During the implosion, the areal density and neutron yield are also discussed.

  17. Effects of fuel-capsule shimming and drive asymmetry on inertial-confinement-fusion symmetry and yield

    DOE PAGESBeta

    Seguin, F. H.; Li, C. K.; DeCiantis, J. L.; Frenje, J. A.; Rygg, J. R.; Petrasso, R. D.; Marshall, F. J.; Smalyuk, V.; Glebov, V. Yu.; Knauer, J. P.; et al

    2016-03-22

    Three orthogonal proton emission imaging cameras were used to study the 3D effects of low-mode drive asymmetries and target asymmetries on nuclear burn symmetry and yield in direct-drive, inertial-confinement-fusion experiments. The fusion yield decreased quickly as the burn region became asymmetric due to either drive or capsule asymmetry. Here, measurements and analytic scaling are used to predict how intentionally asymmetric capsule shells could improve performance by compensating for drive asymmetry when it cannot be avoided (such as with indirect drive or with polar direct drive).

  18. Effects of fuel-capsule shimming and drive asymmetry on inertial-confinement-fusion symmetry and yield

    NASA Astrophysics Data System (ADS)

    Séguin, F. H.; Li, C. K.; DeCiantis, J. L.; Frenje, J. A.; Rygg, J. R.; Petrasso, R. D.; Marshall, F. J.; Smalyuk, V.; Glebov, V. Yu.; Knauer, J. P.; Sangster, T. C.; Kilkenny, J. D.; Nikroo, A.

    2016-03-01

    Three orthogonal proton emission imaging cameras were used to study the 3D effects of low-mode drive asymmetries and target asymmetries on nuclear burn symmetry and yield in direct-drive, inertial-confinement-fusion experiments. The fusion yield decreased quickly as the burn region became asymmetric due to either drive or capsule asymmetry. Measurements and analytic scaling are used to predict how intentionally asymmetric capsule shells could improve performance by compensating for drive asymmetry when it cannot be avoided (such as with indirect drive or with polar direct drive).

  19. Effect of the mounting membrane on shape in inertial confinement fusion implosions

    SciTech Connect

    Nagel, S. R. Haan, S. W.; Rygg, J. R.; Barrios, M.; Benedetti, L. R.; Bradley, D. K.; Field, J. E.; Hammel, B. A.; Izumi, N.; Jones, O. S.; Khan, S. F.; Ma, T.; Pak, A. E.; Tommasini, R.; Town, R. P. J.

    2015-02-15

    The performance of Inertial Confinement Fusion targets relies on the symmetric implosion of highly compressed fuel. X-ray area-backlit imaging is used to assess in-flight low mode 2D asymmetries of the shell. These time-resolved images of the shell exhibit features that can be related to the lift-off position of the membranes used to hold the capsule within the hohlraum. Here, we describe a systematic study of this membrane or “tent” thickness and its impact on the measured low modes for in-flight and self-emission images. The low mode amplitudes of the shell in-flight shape (P{sub 2} and P{sub 4}) are weakly affected by the tent feature in time-resolved, backlit data. By contrast, time integrated self-emission images along the same axis exhibit a reversal in perceived P{sub 4} mode due to growth of a feature seeded by the tent, which can explain prior inconsistencies between the in-flight P{sub 4} and core P{sub 4}, leading to a reevaluation of optimum hohlraum length. Simulations with a tent-like feature normalized to match the feature seen in the backlit images predict a very large impact on the capsule performance from the tent feature.

  20. Laue transmission x-ray spectrograph for inertial confinement fusion (ICF) diagnostics

    NASA Astrophysics Data System (ADS)

    Burek, A. J.

    1992-01-01

    An absolutely calibrated, focusing Laue transmission crystal spectrograph has been developed for inertial confinement fusion (ICF) diagnostics of high-energy x-ray continuum at NOVA. A single flat EddT 020 crystal, 500-μm thick, provides continuous energy coverage over the 5.5-25 keV energy range. The spectrograph is designed with low dispersion and low resolving power E/ΔE of between 10 and 50 for high sensitivity to continuum. Greater resolving power with lower continuum sensitivity is possible by increasing dispersion. The focusing design achieves very low background and provides a compact flat field for coupling to various position sensitive detectors including streak cameras. In addition to EddT, PET 020 has high efficiency in transmission in this energy range and used in the Cauchois geometry achieves high to moderate resolving power that is independent of ICF source size. Initial experiments with gold targets at NOVA with the EddT spectrograph show high sensitivity for single shot recording of continuum and gold L lines on Kodak DEF film. Factors affecting instrument design, resolving power, and sensitivity will be discussed.

  1. Benchmarking atomic physics models for magnetically confined fusion plasma physics experiments

    NASA Astrophysics Data System (ADS)

    May, M. J.; Finkenthal, M.; Soukhanovskii, V.; Stutman, D.; Moos, H. W.; Pacella, D.; Mazzitelli, G.; Fournier, K.; Goldstein, W.; Gregory, B.

    1999-01-01

    In present magnetically confined fusion devices, high and intermediate Z impurities are either puffed into the plasma for divertor radiative cooling experiments or are sputtered from the high Z plasma facing armor. The beneficial cooling of the edge as well as the detrimental radiative losses from the core of these impurities can be properly understood only if the atomic physics used in the modeling of the cooling curves is very accurate. To this end, a comprehensive experimental and theoretical analysis of some relevant impurities is undertaken. Gases (Ne, Ar, Kr, and Xe) are puffed and nongases are introduced through laser ablation into the FTU tokamak plasma. The charge state distributions and total density of these impurities are determined from spatial scans of several photometrically calibrated vacuum ultraviolet and x-ray spectrographs (3-1600 Å), the multiple ionization state transport code transport code (MIST) and a collisional radiative model. The radiative power losses are measured with bolometery, and the emissivity profiles were measured by a visible bremsstrahlung array. The ionization balance, excitation physics, and the radiative cooling curves are computed from the Hebrew University Lawrence Livermore atomic code (HULLAC) and are benchmarked by these experiments. (Supported by U.S. DOE Grant No. DE-FG02-86ER53214 at JHU and Contract No. W-7405-ENG-48 at LLNL.)

  2. Ultrafast picket fence pulse trains to enhance frequency conversion of shaped inertial confinement fusion laser pulses.

    PubMed

    Rothenberg, J E

    2000-12-20

    A high-frequency train of 5-100-ps pulses (picket fence) is proposed to improve significantly the third-harmonic frequency conversion of Nd:glass lasers that are used to generate high-contrast-shaped pulses for inertial confinement fusion (ICF) targets. High conversion efficiency of the low-power foot of a shaped ICF pulse is obtained by use of a low duty cycle, multi-gigahertz train of approximately 20-ps pulses with high peak power. Even with less than 10% duty cycle, continuous illumination is maintained on the target by a combination of temporal broadening schemes. The picket fence approach is analyzed, and the practical limits are identified as applied to the National Ignition Facility laser. It is found that the higher conversion efficiency allows approximately 40% more third-harmonic energy to be delivered to the target, potentially enabling the larger drive needed for high-yield ICF target designs. In addition, the frequency conversion efficiency of these short pulses saturates much more readily, which reduces the transfer of fluctuations at the fundamental and thus greatly improves the power stability of the third harmonic. PMID:18354706

  3. First-principles equation of state of polystyrene and its effect on inertial confinement fusion implosions.

    PubMed

    Hu, S X; Collins, L A; Goncharov, V N; Kress, J D; McCrory, R L; Skupsky, S

    2015-10-01

    Obtaining an accurate equation of state (EOS) of polystyrene (CH) is crucial to reliably design inertial confinement fusion (ICF) capsules using CH/CH-based ablators. With first-principles calculations, we have investigated the extended EOS of CH over a wide range of plasma conditions (ρ=0.1to100g/cm(3) and T=1000 to 4,000,000 K). When compared with the widely used SESAME-EOS table, the first-principles equation of state (FPEOS) of CH has shown significant differences in the low-temperature regime, in which strong coupling and electron degeneracy play an essential role in determining plasma properties. Hydrodynamic simulations of cryogenic target implosions on OMEGA using the FPEOS table of CH have predicted ∼30% decrease in neutron yield in comparison with the usual SESAME simulations. This is attributed to the ∼5% reduction in implosion velocity that is caused by the ∼10% lower mass ablation rate of CH predicted by FPEOS. Simulations using CH-FPEOS show better agreement with measurements of Hugoniot temperature and scattered light from ICF implosions. PMID:26565353

  4. First-principles equation of state of polystyrene and its effect on inertial confinement fusion implosions

    NASA Astrophysics Data System (ADS)

    Hu, S. X.; Collins, L. A.; Goncharov, V. N.; Kress, J. D.; McCrory, R. L.; Skupsky, S.

    2015-10-01

    Obtaining an accurate equation of state (EOS) of polystyrene (CH) is crucial to reliably design inertial confinement fusion (ICF) capsules using CH/CH-based ablators. With first-principles calculations, we have investigated the extended EOS of CH over a wide range of plasma conditions (ρ =0.1 to 100 g /cm3 and T =1000 to 4 000 000 K ). When compared with the widely used SESAME-EOS table, the first-principles equation of state (FPEOS) of CH has shown significant differences in the low-temperature regime, in which strong coupling and electron degeneracy play an essential role in determining plasma properties. Hydrodynamic simulations of cryogenic target implosions on OMEGA using the FPEOS table of CH have predicted ˜30% decrease in neutron yield in comparison with the usual SESAME simulations. This is attributed to the ˜5% reduction in implosion velocity that is caused by the ˜10% lower mass ablation rate of CH predicted by FPEOS. Simulations using CH-FPEOS show better agreement with measurements of Hugoniot temperature and scattered light from ICF implosions.

  5. Mitigating laser imprint in direct-drive inertial confinement fusion implosions with high-Z dopants.

    PubMed

    Hu, S X; Fiksel, G; Goncharov, V N; Skupsky, S; Meyerhofer, D D; Smalyuk, V A

    2012-05-11

    Nonuniformities seeded by both long- and short-wavelength laser perturbations can grow via Rayleigh-Taylor (RT) instability in direct-drive inertial confinement fusion, leading to performance reduction in low-adiabat implosions. To mitigate the effect of laser imprinting on target performance, spherical RT experiments have been performed on OMEGA using Si- or Ge-doped plastic targets in a cone-in-shell configuration. Compared to a pure plastic target, radiation preheating from these high-Z dopants (Si/Ge) increases the ablation velocity and the standoff distance between the ablation front and laser-deposition region, thereby reducing both the imprinting efficiency and the RT growth rate. Experiments showed a factor of 2-3 reduction in the laser-imprinting efficiency and a reduced RT growth rate, leading to significant (3-5 times) reduction in the σ(rms) of shell ρR modulation for Si- or Ge-doped targets. These features are reproduced by radiation-hydrodynamics simulations using the two-dimensional hydrocode DRACO. PMID:23003051

  6. Effects of electron-ion temperature equilibration on inertial confinement fusion implosions.

    PubMed

    Xu, Barry; Hu, S X

    2011-07-01

    The electron-ion temperature relaxation essentially affects both the laser absorption in coronal plasmas and the hot-spot formation in inertial confinement fusion (ICF). It has recently been reexamined for plasma conditions closely relevant to ICF implosions using either classical molecular-dynamics simulations or analytical methods. To explore the electron-ion temperature equilibration effects on ICF implosion performance, we have examined two Coulomb logarithm models by implementing them into our hydrocodes, and we have carried out hydrosimulations for ICF implosions. Compared to the Lee-More model that is currently used in our standard hydrocodes, the two models predict substantial differences in laser absorption, coronal temperatures, and neutron yields for ICF implosions at the OMEGA Laser Facility [Boehly et al. Opt. Commun. 133, 495 (1997)]. Such effects on the triple-picket direct-drive design at the National Ignition Facility (NIF) have also been explored. Based on the validity of the two models, we have proposed a combined model of the electron-ion temperature-relaxation rate for the overall ICF plasma conditions. The hydrosimulations using the combined model for OMEGA implosions have shown ∼6% more laser absorption, ∼6%-15% higher coronal temperatures, and ∼10% more neutron yield, when compared to the Lee-More model prediction. It is also noticed that the gain for the NIF direct-drive design can be varied by ∼10% among the different electron-ion temperature-relaxation models. PMID:21867323

  7. Development of the large neutron imaging system for inertial confinement fusion experiments.

    PubMed

    Caillaud, T; Landoas, O; Briat, M; Kime, S; Rossé, B; Thfoin, I; Bourgade, J L; Disdier, L; Glebov, V Yu; Marshall, F J; Sangster, T C

    2012-03-01

    Inertial confinement fusion (ICF) requires a high resolution (~10 μm) neutron imaging system to observe deuterium and tritium (DT) core implosion asymmetries. A new large (150 mm entrance diameter: scaled for Laser MégaJoule [P. A. Holstein, F. Chaland, C. Charpin, J. M. Dufour, H. Dumont, J. Giorla, L. Hallo, S. Laffite, G. Malinie, Y. Saillard, G. Schurtz, M. Vandenboomgaerde, and F. Wagon, Laser and Particle Beams 17, 403 (1999)]) neutron imaging detector has been developed for such ICF experiments. The detector has been fully characterized using a linear accelerator and a (60)Co γ-ray source. A penumbral aperture was used to observe DT-gas-filled target implosions performed on the OMEGA laser facility. [T. R. Boehly, D. L. Brown, R. S. Craxton, R. L. Keck, J. P. Knauer, J. H. Kelly, T. J. Kessler, S. A. Kumpan, S. J. Loucks, S. A. Letzring, F. J. Marshall, R. L. McCrory, S. F. B. Morse, W. Seka, J. M. Soures, and C. P. Verdon, Opt. Commun. 133, 495 (1997)] Neutron core images of 14 MeV with a resolution of 15 μm were obtained and are compared to x-ray images of comparable resolution. PMID:22462917

  8. Investigation of radial wire arrays for inertial confinement fusion and radiation effects science.

    SciTech Connect

    Serrano, Jason Dimitri; Bland, Simon Nicholas; McBride, Ryan D.; Chittenden, Jeremy Paul; Suzuki-Vidal, Francisco Andres; Jennings, Christopher A.; Hall, Gareth Neville; Ampleford, David J.; Peyton, Bradley Philip; Lebedev, Sergey V.; Cleveland, Monica; Rogers, Thomas John; Cuneo, Michael Edward; Coverdale, Christine Anne; Jones, Brent Manley; Jones, Michael C.

    2010-02-01

    Radial wire arrays provide an alternative x-ray source for Z-pinch driven Inertial Confinement Fusion. These arrays, where wires are positioned radially outwards from a central cathode to a concentric anode, have the potential to drive a more compact ICF hohlraum. A number of experiments were performed on the 7MA Saturn Generator. These experiments studied a number of potential risks in scaling radial wire arrays up from the 1MA level, where they have been shown to provide similar x-ray outputs to larger diameter cylindrical arrays, to the higher current levels required for ICF. Data indicates that at 7MA radial arrays can obtain higher power densities than cylindrical wire arrays, so may be of use for x-ray driven ICF on future facilities. Even at the 7MA level, data using Saturn's short pulse mode indicates that a radial array should be able to drive a compact hohlraum to temperatures {approx}92eV, which may be of interest for opacity experiments. These arrays are also shown to have applications to jet production for laboratory astrophysics. MHD simulations require additional physics to match the observed behavior.

  9. Development of the large neutron imaging system for inertial confinement fusion experiments

    NASA Astrophysics Data System (ADS)

    Caillaud, T.; Landoas, O.; Briat, M.; Kime, S.; Rossé, B.; Thfoin, I.; Bourgade, J. L.; Disdier, L.; Glebov, V. Yu.; Marshall, F. J.; Sangster, T. C.

    2012-03-01

    Inertial confinement fusion (ICF) requires a high resolution (˜10 μm) neutron imaging system to observe deuterium and tritium (DT) core implosion asymmetries. A new large (150 mm entrance diameter: scaled for Laser MégaJoule [P. A. Holstein, F. Chaland, C. Charpin, J. M. Dufour, H. Dumont, J. Giorla, L. Hallo, S. Laffite, G. Malinie, Y. Saillard, G. Schurtz, M. Vandenboomgaerde, and F. Wagon, Laser and Particle Beams 17, 403 (1999), 10.1017/S0263034699173087]) neutron imaging detector has been developed for such ICF experiments. The detector has been fully characterized using a linear accelerator and a 60Co γ-ray source. A penumbral aperture was used to observe DT-gas-filled target implosions performed on the OMEGA laser facility. [T. R. Boehly, D. L. Brown, R. S. Craxton, R. L. Keck, J. P. Knauer, J. H. Kelly, T. J. Kessler, S. A. Kumpan, S. J. Loucks, S. A. Letzring, F. J. Marshall, R. L. McCrory, S. F. B. Morse, W. Seka, J. M. Soures, and C. P. Verdon, Opt. Commun. 133, 495 (1997), 10.1016/S0030-4018(96)00325-2] Neutron core images of 14 MeV with a resolution of 15 μm were obtained and are compared to x-ray images of comparable resolution.

  10. Development of backlighting sources for a Compton radiography diagnostic of Inertial Confinement Fusion targets

    SciTech Connect

    Tommasini, R; MacPhee, A; Hey, D; Ma, T; Chen, C; Izumi, N; Unites, W; MacKinnon, A; Hatchett, S P; Remington, B A; Park, H S; Springer, P; Koch, J A; Landen, O L; Seely, J; Holland, G; Hudson, L

    2008-05-07

    We present scaled demonstrations of backlighter sources, emitting Bremsstrahlung x-rays with photon energies above 75 keV, that we will use to record x-ray Compton radiographic snapshots of cold dense DT fuel in inertial confinement fusion implosions at the National Ignition Facility (NIF). In experiments performed at the Titan laser facility at Lawrence Livermore National Laboratory, we measured the source size and the Bremsstrahlung spectrum as a function of laser intensity and pulse length, from solid targets irradiated at 2e17-5e18 W/cm{sup 2} using 2-40 ps pulses. Using Au planar foils we achieved source sizes down to 5.5 {micro}m, and conversion efficiencies of about 1e-3 J/J into x-ray photons with energies in the 75-100 keV spectral range. We can now use these results to design NIF backlighter targets and shielding, and to predict Compton radiography performance as a function of the NIF implosion yield and associated background.

  11. Development of backlighting sources for a Compton radiography diagnostic of inertial confinement fusion targets (invited)

    SciTech Connect

    Tommasini, R.; MacPhee, A.; Hey, D.; Ma, T.; Chen, C.; Izumi, N.; Unites, W.; MacKinnon, A.; Hatchett, S. P.; Remington, B. A.; Park, H. S.; Springer, P.; Koch, J. A.; Landen, O. L.; Seely, John; Holland, Glenn; Hudson, Larry

    2008-10-15

    We present scaled demonstrations of backlighter sources, emitting bremsstrahlung x rays with photon energies above 75 keV, that we will use to record x-ray Compton radiographic snapshots of cold dense DT fuel in inertial confinement fusion implosions at the National Ignition Facility (NIF). In experiments performed at the Titan laser facility at Lawrence Livermore National Laboratory, we measured the source size and the bremsstrahlung spectrum as a function of laser intensity and pulse length from solid targets irradiated at 2x10{sup 17}-5x10{sup 18} W/cm{sup 2} using 2-40 ps pulses. Using Au planar foils we achieved source sizes down to 5.5 {mu}m and conversion efficiencies of about 1x10{sup -13} J/J into x-ray photons with energies in the 75-100 keV spectral range. We can now use these results to design NIF backlighter targets and shielding and to predict Compton radiography performance as a function of the NIF implosion yield and associated background.

  12. Observations of the Ablative Richtmyer-Meshkov Effect Relevant to Indirect-Drive Inertial Confinement Fusion

    NASA Astrophysics Data System (ADS)

    Loomis, Eric; Braun, Dave; Batha, Steve; Landen, Otto

    2013-10-01

    Recent simulations and experiments have shown that isolated features on the outer surface of Inertial Confinement Fusion (ICF) ignition capsules can profoundly impact capsule performance by leading to material jetting or mixing into the hotspot. Controlling the growth of these artifacts is complicated due to uncertainties in equation of state (EOS) models used in simulation codes. Here we report on measurements pertaining to the growth and decay of isolated defects due to x-ray ablation Richtmyer-Meshkov in CH capsules in order to validate these models. Face-on transmission radiography was used to measure the evolution of Gaussian bump arrays in plastic targets. Au halfraums heated to radiation temperatures near 70 eV using 15 beams in a 7.5 ns pulse from the Omega laser (Laboratory for Laser Energetics, University of Rochester, NY) indirectly drove the samples while simultaneous radiographs from Ta and Y backlighter foils were recorded. Shock speed measurements were also made with Omega's Active Shock Break Out (ASBO) diagnostic in conjunction with the x-ray flux recorded by a soft x-ray power diagnostic (DANTE) were used to determine drive conditions in the target. Measurements of 5 micron tall, 17 micron wide bumps show a decrease in bump areal density between 4.5 and 7.5 ns while 33 micron wide bumps saturate near 3 ns consistent with LEOS 5310 and SESAME 7592 simulations.

  13. Fast ignition of a compressed inertial confinement fusion hemispherical capsule by two proton beams

    SciTech Connect

    Temporal, Mauro

    2006-12-15

    A hemispherical conically guided indirectly driven inertial confinement fusion capsule has been considered. The fast ignition of the precompressed capsule driven by one or two laser-accelerated proton beams has been numerically investigated. The energy distribution of the protons is Gaussian with a mean energy of 12 MeV and a full width at half maximum of 1 MeV. A new scheme that uses two laser-accelerated proton beams is proposed. It is found that the energy deposition of 1 kJ provided by a first proton beam generates a low-density cylindrical channel and launches a forward shock. A second proton beam, delayed by a few tens of ps and driving the energy of 6 kJ, crosses the low-density channel and heats the dense shocked region where the ignition of the deuterium-tritium nuclear fuel is achieved. For the considered capsule, this new two-beam configuration reduces the ignition energy threshold to 7 kJ.

  14. Plasma viscosity with mass transport in spherical inertial confinement fusion implosion simulations

    SciTech Connect

    Vold, E. L.; Molvig, K.; Joglekar, A. S.; Ortega, M. I.; Moll, R.; Fenn, D.

    2015-11-15

    The effects of viscosity and small-scale atomic-level mixing on plasmas in inertial confinement fusion (ICF) currently represent challenges in ICF research. Many current ICF hydrodynamic codes ignore the effects of viscosity though recent research indicates viscosity and mixing by classical transport processes may have a substantial impact on implosion dynamics. We have implemented a Lagrangian hydrodynamic code in one-dimensional spherical geometry with plasma viscosity and mass transport and including a three temperature model for ions, electrons, and radiation treated in a gray radiation diffusion approximation. The code is used to study ICF implosion differences with and without plasma viscosity and to determine the impacts of viscosity on temperature histories and neutron yield. It was found that plasma viscosity has substantial impacts on ICF shock dynamics characterized by shock burn timing, maximum burn temperatures, convergence ratio, and time history of neutron production rates. Plasma viscosity reduces the need for artificial viscosity to maintain numerical stability in the Lagrangian formulation and also modifies the flux-limiting needed for electron thermal conduction.

  15. Inhibition of turbulence in inertial-confinement-fusion hot spots by viscous dissipation.

    PubMed

    Weber, C R; Clark, D S; Cook, A W; Busby, L E; Robey, H F

    2014-05-01

    Achieving ignition in inertial confinement fusion (ICF) requires the formation of a high-temperature (>10 keV) central hot spot. Turbulence has been suggested as a mechanism for degrading the hot-spot conditions by altering transport properties, introducing colder, mixed material, or reducing the conversion of radially directed kinetic energy to hot-spot heating. We show, however, that the hot spot is very viscous, and the assumption of turbulent conditions in the hot spot is incorrect. This work presents the first high-resolution, three-dimensional simulations of National Ignition Facility (NIF) implosion experiments using detailed knowledge of implosion dynamics and instability seeds and including an accurate model of physical viscosity. We find that when viscous effects are neglected, the hot spot can exhibit a turbulent kinetic energy cascade. Viscous effects, however, are significant and strongly damp small-scale velocity structures, with a hot-spot Reynolds number in the range of only 10-100. PMID:25353903

  16. Performance of large-aperture optical switches for high-energy inertial-confinement fusion lasers

    SciTech Connect

    Rhodes, M.A.; Woods, B.; DeYoreo, J.J.; Roberts, D.; Atherton, L.J.

    1995-08-20

    We describe the design and performance of large-aperture ({lt}30 cm {times} 30 cm) optical switches that have demonstrated, for the first time to our knowledge, active switching of a high-energy ({lt}5 kJ) optical pulse in an inertial-confinement fusion laser. These optical switches, which consist of a plasma-electrode Pockels cell (PEPC) and a passive polarizer, permit the design of efficient, multipass laser amplifiers. In a PEPC, plasma discharges on the faces of a thin (1-cm) electro-optic crystal (KDP or KD{bold |}P) act as highly conductive and transparent electrodes. These plasma electrodes facilitate rapid ({lt}100 ns) and uniform charging of the crystal to the half-wave voltage and discharging back to 0 V. We discuss the operating principles, design, optical performance, and technical issues of a 32 cm {times} 32 cm prototype PEPC with both KDP and KD{bold |}P crystals, and a 37 cm {times} 37 cm PEPC with a KDP crystal for the Beamlet laser. This PEPC recently switched a 6-kJ, 3-ns pulse in a four-pass cavity.

  17. Neutron attenuation in the laser ducts of an inertial-confinement fusion reactor

    SciTech Connect

    Augustine, F. Jr.

    1981-11-01

    This report deals with the problem of neutron streaming through the laser beam ducts of an inertial confinement fusion power plant. The neutron flux through these ducts must be attenuated by a factor of 10/sup 12/ to meet radiological safety limits. The problem is dealt with by using mirrors to bend the path of the laser beam while cutting off a line of sight path for neutrons. The Monte Carlo Code MCNP was used to analyze the two mirror SOLASE design, which only attenuated the neutron flux by a factor of 10/sup 3/. The Westinghouse design, initially assuming four mirrors, attenuated the neutron flux by 10/sup 4/ per mirror bend, and hence only three mirror bends were needed. Further studies also revealed that the large length/diameter ratio of the ducts and the thinner mirror design were crucial to the large attenuation. It may also be possible to develop a two mirror system, at 10/sup 6/ attenuation per mirror bend, utilizing improvements such as point cross overs, a second flux trap, and acute column-to-column angles. Further studies are needed to check this possibility.

  18. Plasma viscosity with mass transport in spherical inertial confinement fusion implosion simulations

    NASA Astrophysics Data System (ADS)

    Vold, E. L.; Joglekar, A. S.; Ortega, M. I.; Moll, R.; Fenn, D.; Molvig, K.

    2015-11-01

    The effects of viscosity and small-scale atomic-level mixing on plasmas in inertial confinement fusion (ICF) currently represent challenges in ICF research. Many current ICF hydrodynamic codes ignore the effects of viscosity though recent research indicates viscosity and mixing by classical transport processes may have a substantial impact on implosion dynamics. We have implemented a Lagrangian hydrodynamic code in one-dimensional spherical geometry with plasma viscosity and mass transport and including a three temperature model for ions, electrons, and radiation treated in a gray radiation diffusion approximation. The code is used to study ICF implosion differences with and without plasma viscosity and to determine the impacts of viscosity on temperature histories and neutron yield. It was found that plasma viscosity has substantial impacts on ICF shock dynamics characterized by shock burn timing, maximum burn temperatures, convergence ratio, and time history of neutron production rates. Plasma viscosity reduces the need for artificial viscosity to maintain numerical stability in the Lagrangian formulation and also modifies the flux-limiting needed for electron thermal conduction.

  19. Neutron flux assessment of a neutron irradiation facility based on inertial electrostatic confinement fusion.

    PubMed

    Sztejnberg Gonçalves-Carralves, M L; Miller, M E

    2015-12-01

    Neutron generators based on inertial electrostatic confinement fusion were considered for the design of a neutron irradiation facility for explanted organ Boron Neutron Capture Therapy (BNCT) that could be installed in a health care center as well as in research areas. The chosen facility configuration is "irradiation chamber", a ~20×20×40 cm(3) cavity near or in the center of the facility geometry where samples to be irradiated can be placed. Neutron flux calculations were performed to study different manners for improving scattering processes and, consequently, optimize neutron flux in the irradiation position. Flux distributions were assessed through numerical simulations of several models implemented in MCNP5 particle transport code. Simulation results provided a wide spectrum of combinations of net fluxes and energy spectrum distributions. Among them one can find a group that can provide thermal neutron fluxes per unit of production rate in a range from 4.1·10(-4) cm(-2) to 1.6·10(-3) cm(-2) with epithermal-to-thermal ratios between 0.3% and 13% and fast-to-thermal ratios between 0.01% to 8%. Neutron generators could be built to provide more than 10(10) n s(-1) and, consequently, with an arrangement of several generators appropriate enough neutron fluxes could be obtained that would be useful for several BNCT-related irradiations and, eventually, for clinical practice. PMID:26122974

  20. Sensitivity of inertial confinement fusion hot spot properties to the deuterium-tritium fuel adiabat

    NASA Astrophysics Data System (ADS)

    Melvin, J.; Lim, H.; Rana, V.; Cheng, B.; Glimm, J.; Sharp, D. H.; Wilson, D. C.

    2015-02-01

    We determine the dependence of key Inertial Confinement Fusion (ICF) hot spot simulation properties on the deuterium-tritium fuel adiabat, here modified by addition of energy to the cold shell. Variation of this parameter reduces the simulation to experiment discrepancy in some, but not all, experimentally inferred quantities. Using simulations with radiation drives tuned to match experimental shots N120321 and N120405 from the National Ignition Campaign (NIC), we carry out sets of simulations with varying amounts of added entropy and examine the sensitivities of important experimental quantities. Neutron yields, burn widths, hot spot densities, and pressures follow a trend approaching their experimentally inferred quantities. Ion temperatures and areal densities are sensitive to the adiabat changes, but do not necessarily converge to their experimental quantities with the added entropy. This suggests that a modification to the simulation adiabat is one of, but not the only explanation of the observed simulation to experiment discrepancies. In addition, we use a theoretical model to predict 3D mix and observe a slight trend toward less mixing as the entropy is enhanced. Instantaneous quantities are assessed at the time of maximum neutron production, determined dynamically within each simulation. These trends contribute to ICF science, as an effort to understand the NIC simulation to experiment discrepancy, and in their relation to the high foot experiments, which features a higher adiabat in the experimental design and an improved neutron yield in the experimental results.

  1. Energy gain of a thin DT shell target in inertial confinement fusion

    NASA Astrophysics Data System (ADS)

    Khoshbinfar, Soheil

    2014-11-01

    Estimation of maximum possible energy gain for a given energy of driver has always become a key point in inertial confinement fusion. It has direct impact on the cost of produced electricity. Here, we employ a hydrodynamics model to assess energy gain in the case of a symmetrical hydrodynamics implosion where a narrow fuel shell consisting of deuterium-tritium (DT), can experience an isentropic compression in a self-similar regime. Introducing a set of six state parameters {Hhs, Ths, Uimp, αc, ξhs and μhs}, the final fuel state close to ignition is fully described. It enables us to calculate energy gain curves for specific set of these state variables. The envelope of the energy gain family curves provide a limiting gain curve Gfuel fuel* ∝ Ef0.36. Next, we took into account the inertial of cold surrounding fuel on the ignition process. It changes the limiting gain curve slope to 0.41. Finally, the analytical model results assessed and validated using numerical simulation code.

  2. Analysis of the neutron time-of-flight spectra from inertial confinement fusion experiments

    SciTech Connect

    Hatarik, R. Sayre, D. B.; Caggiano, J. A.; Phillips, T.; Eckart, M. J.; Bond, E. J.; Cerjan, C.; Grim, G. P.; Hartouni, E. P.; Mcnaney, J. M.; Munro, D. H.; Knauer, J. P.

    2015-11-14

    Neutron time-of-flight diagnostics have long been used to characterize the neutron spectrum produced by inertial confinement fusion experiments. The primary diagnostic goals are to extract the d + t → n + α (DT) and d + d → n + {sup 3}He (DD) neutron yields and peak widths, and the amount DT scattering relative to its unscattered yield, also known as the down-scatter ratio (DSR). These quantities are used to infer yield weighted plasma conditions, such as ion temperature (T{sub ion}) and cold fuel areal density. We report on novel methodologies used to determine neutron yield, apparent T{sub ion}, and DSR. These methods invoke a single temperature, static fluid model to describe the neutron peaks from DD and DT reactions and a spline description of the DT spectrum to determine the DSR. Both measurements are performed using a forward modeling technique that includes corrections for line-of-sight attenuation and impulse response of the detection system. These methods produce typical uncertainties for DT T{sub ion} of 250 eV, 7% for DSR, and 9% for the DT neutron yield. For the DD values, the uncertainties are 290 eV for T{sub ion} and 10% for the neutron yield.

  3. Analysis of the neutron time-of-flight spectra from inertial confinement fusion experiments

    NASA Astrophysics Data System (ADS)

    Hatarik, R.; Sayre, D. B.; Caggiano, J. A.; Phillips, T.; Eckart, M. J.; Bond, E. J.; Cerjan, C.; Grim, G. P.; Hartouni, E. P.; Knauer, J. P.; Mcnaney, J. M.; Munro, D. H.

    2015-11-01

    Neutron time-of-flight diagnostics have long been used to characterize the neutron spectrum produced by inertial confinement fusion experiments. The primary diagnostic goals are to extract the d + t → n + α (DT) and d + d → n + 3He (DD) neutron yields and peak widths, and the amount DT scattering relative to its unscattered yield, also known as the down-scatter ratio (DSR). These quantities are used to infer yield weighted plasma conditions, such as ion temperature (Tion) and cold fuel areal density. We report on novel methodologies used to determine neutron yield, apparent Tion, and DSR. These methods invoke a single temperature, static fluid model to describe the neutron peaks from DD and DT reactions and a spline description of the DT spectrum to determine the DSR. Both measurements are performed using a forward modeling technique that includes corrections for line-of-sight attenuation and impulse response of the detection system. These methods produce typical uncertainties for DT Tion of 250 eV, 7% for DSR, and 9% for the DT neutron yield. For the DD values, the uncertainties are 290 eV for Tion and 10% for the neutron yield.

  4. Sensitivity of inertial confinement fusion hot spot properties to the deuterium-tritium fuel adiabat

    SciTech Connect

    Melvin, J.; Lim, H.; Rana, V.; Glimm, J.; Cheng, B.; Sharp, D. H.; Wilson, D. C.

    2015-02-15

    We determine the dependence of key Inertial Confinement Fusion (ICF) hot spot simulation properties on the deuterium-tritium fuel adiabat, here modified by addition of energy to the cold shell. Variation of this parameter reduces the simulation to experiment discrepancy in some, but not all, experimentally inferred quantities. Using simulations with radiation drives tuned to match experimental shots N120321 and N120405 from the National Ignition Campaign (NIC), we carry out sets of simulations with varying amounts of added entropy and examine the sensitivities of important experimental quantities. Neutron yields, burn widths, hot spot densities, and pressures follow a trend approaching their experimentally inferred quantities. Ion temperatures and areal densities are sensitive to the adiabat changes, but do not necessarily converge to their experimental quantities with the added entropy. This suggests that a modification to the simulation adiabat is one of, but not the only explanation of the observed simulation to experiment discrepancies. In addition, we use a theoretical model to predict 3D mix and observe a slight trend toward less mixing as the entropy is enhanced. Instantaneous quantities are assessed at the time of maximum neutron production, determined dynamically within each simulation. These trends contribute to ICF science, as an effort to understand the NIC simulation to experiment discrepancy, and in their relation to the high foot experiments, which features a higher adiabat in the experimental design and an improved neutron yield in the experimental results.

  5. First-principles investigations on ionization and thermal conductivity of polystyrene for inertial confinement fusion applications

    DOE PAGESBeta

    Hu, S. X.; Collins, L. A.; Goncharov, V. N.; Kress, J. D.; McCrory, R. L.; Skupsky, S.

    2016-04-14

    Using quantum molecular-dynamics (QMD) methods based on the density functional theory, we have performed first-principles investigations on the ionization and thermal conductivity of polystyrene (CH) over a wide range of plasma conditions (ρ = 0.5 to 100 g/cm3 and T = 15,625 to 500,000 K). The ionization data from orbital-free molecular-dynamics calculations have been fitted with a “Saha-type” model as a function of the CH plasma density and temperature, which exhibits the correct behaviors of continuum lowering and pressure ionization. The thermal conductivities (κQMD) of CH, derived directly from the Kohn–Sham molecular-dynamics calculations, are then analytically fitted with a generalizedmore » Coulomb logarithm [(lnΛ)QMD] over a wide range of plasma conditions. When compared with the traditional ionization and thermal conductivity models used in radiation–hydrodynamics codes for inertial confinement fusion simulations, the QMD results show a large difference in the low-temperature regime in which strong coupling and electron degeneracy play an essential role in determining plasma properties. Furthermore, hydrodynamic simulations of cryogenic deuterium–tritium targets with CH ablators on OMEGA and the National Ignition Facility using the QMD-derived ionization and thermal conductivity of CH have predicted –20% variation in target performance in terms of hot-spot pressure and neutron yield (gain) with respect to traditional model simulations.« less

  6. Interaction physics for the shock ignition scheme of inertial confinement fusion targets

    NASA Astrophysics Data System (ADS)

    Depierreux, S.; Goyon, C.; Lewis, K.; Bandulet, H.; Michel, D. T.; Loisel, G.; Yahia, V.; Tassin, V.; Stenz, C.; Borisenko, N. G.; Nazarov, W.; Limpouch, J.; Masson Laborde, P. E.; Loiseau, P.; Casanova, M.; Nicolaï, Ph; Hüller, S.; Pesme, D.; Riconda, C.; Tikhonchuk, V. T.; Labaune, C.

    2011-12-01

    This paper presents an analysis of laser-plasma interaction risks of the shock ignition (SI) scheme and experimental results under conditions relevant to the corona of a compressed target. Experiments are performed on the LIL facility at the 10 kJ level, on the LULI 2000 facility with two beams at the kJ level and on the LULI 6-beam facility with 100 J in each beam. Different aspects of the interaction of the SI pulse are studied exploiting either the flexibility of the LULI 6-beam facility to produce a very high intensity pulse or the high energy of the LIL to produce long and hot plasmas. A continuity is found allowing us to draw some conclusions regarding the coupling quality and efficiency of the SI spike pulse. It is shown that the propagation of the SI beams in the underdense plasma present in the corona of inertial confinement fusion targets could strongly modify the initial spot size of the beam through filamentation. Detailed experimental studies of the growth and saturation of backscattering instabilities in these plasmas indicate that significant levels of stimulated scattering reflectivities (larger than 40%) may be reached at least for some time during the SI pulse.

  7. Advances in HYDRA and its application to simulations of Inertial Confinement Fusion targets

    NASA Astrophysics Data System (ADS)

    Marinak, M. M.; Kerbel, G. D.; Koning, J. M.; Patel, M. V.; Sepke, S. M.; Brown, P. N.; Chang, B.; Procassini, R.; Veitzer, S. A.

    2008-11-01

    We will outline new capabilities added to the HYDRA 2D/3D multiphysics ICF simulation code. These include a new SN multigroup radiation transport package (1D), constitutive models for elastic-plastic (strength) effects, and a mix model. A Monte Carlo burn package is being incorporated to model diagnostic signatures of neutrons, gamma rays and charged particles. A 3D MHD package that treats resistive MHD is available. Improvements to HYDRA's implicit Monte Carlo photonics package, including the addition of angular biasing, now enable integrated hohlraum simulations to complete in substantially shorter time. The heavy ion beam deposition package now includes a new model for ion stopping power developed by the Tech-X Corporation, with improved accuracy below the Bragg peak. Examples will illustrate HYDRA's enhanced capabilities to simulate various aspects of inertial confinement fusion targets.This work was performed under the auspices of the Lawrence Livermore National Security, LLC, (LLNS) under Contract No. DE-AC52-07NA27344. The work of Tech-X personnel was funded by the Department of Energy under Small Business Innovation Research Contract No. DE-FG02-03ER83797.

  8. Double emulsion generation in the mass production of inertial confinement fusion targets using T-junctions

    NASA Astrophysics Data System (ADS)

    Moynihan, Matthew J.

    This work demonstrates a new device for the continuous controlled production of double emulsions for the manufacturing of inertial confinement fusion targets. This device can be integrated into a microfluidic approach to produce targets which should increase the yield and quality of the targets and at a lower cost. The device is a double T-Junction, which has been scaled, optimized and built to produce oil-in-water-in-oil double emulsions from diameters of roughly 4 mm or less. A T-Junction is an intersection of two channels at a right angle where fluid emerges and is broken off to form droplets. A systematic study presented here has shown that a single T-Junction has four modes of operation: squeezing, dripping, transition and streaming. The droplet size may be controlled by controlling the fluid flow rate through the channels; the droplet increases with increasing dispersed flow and decreasing continuous flow. The device was utilized to produce hundreds of ˜ 2.5 mm diameter resorcinol formaldehyde double emulsions with better than 2 percent reproducibility in diameter. The device was used to produce 2.0 mm shells with an average wall thickness of 510 microns.

  9. Fast-Shock Ignition: A New Concept to Inertial Confinement Fusion

    NASA Astrophysics Data System (ADS)

    Ghasemi, Seyed; Farahbod, Amir; Laser Plasma Interaction Team

    2013-03-01

    A new concept for inertial confinement fusion called fast-shock ignition (FSI) is introduced to obtain high target gain. In the proposed model, the separation of fuel ignition into two successive steps, under the suitable conditions, reduces required ignitor energy. The main procedure in FSI concept is at first, compressing the fuel up to stagnation. Then, two high intensity short pulse laser spikes with energy and power lower than those required for shock ignition (SI) and fast ignition (FI) with a proper delay time launched at the fuel which increases the central hot-spot temperature and complete the ignition of the pre compressed fuel. The introduced semi-analytical model indicates that with fast-shock ignition, the total required energy for compression and ignition of the fuel can be slightly reduced in comparison with pure shock ignition. Furthermore, for fuel mass greater than 2mg, the target energy gain increases up to 15 percent and the contribution of fast ignitor could be decreased about 20 percent over pure fast ignition. The FSI scheme is beneficial from technological considerations for the construction of short pulse high power laser drivers. The general advantages of fast-shock ignition over pure shock ignition can be better than 1.3.

  10. Collection of solid and gaseous samples to diagnose inertial confinement fusion implosions

    SciTech Connect

    Stoyer, M. A.; Velsko, C. A.; Spears, B. K.; Hicks, D. G.; Hudson, G. B.; Sangster, T. C.; Freeman, C. G.

    2012-02-15

    Collection of representative samples of debris following inertial confinement fusion implosions in order to diagnose implosion conditions and efficacy is a challenging endeavor because of the unique conditions within the target chamber such as unconverted laser light, intense pulse of x-rays, physical chunks of debris, and other ablative effects. We present collection of gas samples following an implosion for the first time. High collection fractions for noble gases were achieved. We also present collection of solid debris samples on flat plate collectors. Geometrical collection efficiencies for Au hohlraum material were achieved and collection of capsule debris (Be and Cu) was also observed. Asymmetric debris distributions were observed for Au and Be samples. Collection of Be capsule debris was higher for solid collectors viewing the capsule through the laser entrance hole in the hohlraum than for solid collectors viewing the capsule around the waist of the hohlraum. Collection of Au hohlraum material showed the opposite pattern: more Au debris was collected around the waist than through the laser entrance hole. The solid debris collectors were not optimized for minimal Cu backgrounds, which limited the conclusions about the symmetry of the Cu debris. The quality of the data limited conclusions on chemical fractionation effects within the burning, expanding, and then cooling plasma.

  11. Angular radiation temperature simulation for time-dependent capsule drive prediction in inertial confinement fusion

    SciTech Connect

    Jing, Longfei; Yang, Dong; Li, Hang; Zhang, Lu; Lin, Zhiwei; Li, Liling; Kuang, Longyu; Jiang, Shaoen Ding, Yongkun; Huang, Yunbao

    2015-02-15

    The x-ray drive on a capsule in an inertial confinement fusion setup is crucial for ignition. Unfortunately, a direct measurement has not been possible so far. We propose an angular radiation temperature simulation to predict the time-dependent drive on the capsule. A simple model, based on the view-factor method for the simulation of the radiation temperature, is presented and compared with the experimental data obtained using the OMEGA laser facility and the simulation results acquired with VISRAD code. We found a good agreement between the time-dependent measurements and the simulation results obtained using this model. The validated model was then used to analyze the experimental results from the Shenguang-III prototype laser facility. More specifically, the variations of the peak radiation temperatures at different view angles with the albedo of the hohlraum, the motion of the laser spots, the closure of the laser entrance holes, and the deviation of the laser power were investigated. Furthermore, the time-dependent radiation temperature at different orientations and the drive history on the capsule were calculated. The results indicate that the radiation temperature from “U20W112” (named according to the diagnostic hole ID on the target chamber) can be used to approximately predict the drive temperature on the capsule. In addition, the influence of the capsule on the peak radiation temperature is also presented.

  12. Collection of solid and gaseous samples to diagnose inertial confinement fusion implosions.

    PubMed

    Stoyer, M A; Velsko, C A; Spears, B K; Hicks, D G; Hudson, G B; Sangster, T C; Freeman, C G

    2012-02-01

    Collection of representative samples of debris following inertial confinement fusion implosions in order to diagnose implosion conditions and efficacy is a challenging endeavor because of the unique conditions within the target chamber such as unconverted laser light, intense pulse of x-rays, physical chunks of debris, and other ablative effects. We present collection of gas samples following an implosion for the first time. High collection fractions for noble gases were achieved. We also present collection of solid debris samples on flat plate collectors. Geometrical collection efficiencies for Au hohlraum material were achieved and collection of capsule debris (Be and Cu) was also observed. Asymmetric debris distributions were observed for Au and Be samples. Collection of Be capsule debris was higher for solid collectors viewing the capsule through the laser entrance hole in the hohlraum than for solid collectors viewing the capsule around the waist of the hohlraum. Collection of Au hohlraum material showed the opposite pattern: more Au debris was collected around the waist than through the laser entrance hole. The solid debris collectors were not optimized for minimal Cu backgrounds, which limited the conclusions about the symmetry of the Cu debris. The quality of the data limited conclusions on chemical fractionation effects within the burning, expanding, and then cooling plasma. PMID:22380089

  13. Novel free-form hohlraum shape design and optimization for laser-driven inertial confinement fusion

    SciTech Connect

    Jiang, Shaoen; Jing, Longfei Ding, Yongkun; Huang, Yunbao

    2014-10-15

    The hohlraum shape attracts considerable attention because there is no successful ignition method for laser-driven inertial confinement fusion at the National Ignition Facility. The available hohlraums are typically designed with simple conic curves, including ellipses, parabolas, arcs, or Lame curves, which allow only a few design parameters for the shape optimization, making it difficult to improve the performance, e.g., the energy coupling efficiency or radiation drive symmetry. A novel free-form hohlraum design and optimization approach based on the non-uniform rational basis spline (NURBS) model is proposed. In the present study, (1) all kinds of hohlraum shapes can be uniformly represented using NURBS, which is greatly beneficial for obtaining the optimal available hohlraum shapes, and (2) such free-form uniform representation enables us to obtain an optimal shape over a large design domain for the hohlraum with a more uniform radiation and higher drive temperature of the fuel capsule. Finally, a hohlraum is optimized and evaluated with respect to the drive temperature and symmetry at the Shenguang III laser facility in China. The drive temperature and symmetry results indicate that such a free-form representation is advantageous over available hohlraum shapes because it can substantially expand the shape design domain so as to obtain an optimal hohlraum with high performance.

  14. Precision Manufacturing of Inertial Confinement Fusion Double Shell Laser Targets for OMEGA

    SciTech Connect

    Amendt, P A; Bono, M J; Hibbard, R L; Castro, C; Bennett, D W

    2003-11-21

    Double shell targets have been built by Lawrence Livermore National Laboratory (LLNL) for inertial confinement fusion (ICF) experiments on the Omega laser at the University of Rochester and as a prelude to similar experiments on NIF. Of particular interest to ICF studies are high-precision double shell implosion targets for demonstrating thermonuclear ignition without the need for cryogenic preparation. Because the ignition tolerance to interface instabilities is rather low, the manufacturing requirements for smooth surface finishes and shell concentricity are particularly strict. This paper describes a deterministic approach to manufacturing and controlling error sources in each component. Included is the design philosophy of why certain manufacturing techniques were chosen to best reduce the errors within the target. The manufacturing plan developed for this effort created a deterministic process that, once proven, is repeatable. By taking this rigorous approach to controlling all error sources during the manufacture of each component and during assembly, we have achieved the overall 5 {micro}m dimensional requirement with sub-micron surface flaws. Strengths and weaknesses of the manufacturing process will be discussed.

  15. Three-dimensional hydrodynamics of the deceleration stage in inertial confinement fusion

    SciTech Connect

    Weber, C. R. Clark, D. S.; Cook, A. W.; Eder, D. C.; Haan, S. W.; Hammel, B. A.; Hinkel, D. E.; Jones, O. S.; Marinak, M. M.; Milovich, J. L.; Patel, P. K.; Robey, H. F.; Salmonson, J. D.; Sepke, S. M.; Thomas, C. A.

    2015-03-15

    The deceleration stage of inertial confinement fusion implosions is modeled in detail using three-dimensional simulations designed to match experiments at the National Ignition Facility. In this final stage of the implosion, shocks rebound from the center of the capsule, forming the high-temperature, low-density hot spot and slowing the incoming fuel. The flow field that results from this process is highly three-dimensional and influences many aspects of the implosion. The interior of the capsule has high-velocity motion, but viscous effects limit the range of scales that develop. The bulk motion of the hot spot shows qualitative agreement with experimental velocity measurements, while the variance of the hot spot velocity would broaden the DT neutron spectrum, increasing the inferred temperature by 400–800 eV. Jets of ablator material are broken apart and redirected as they enter this dynamic hot spot. Deceleration stage simulations using two fundamentally different rad-hydro codes are compared and the flow field is found to be in good agreement.

  16. First-principles equation of state of polystyrene and its effect on inertial confinement fusion implosions

    DOE PAGESBeta

    Hu, S. X.; Collins, L. A.; Goncharov, V. N.; Kress, J. D.; McCrory, R. L.; Skupsky, S.

    2015-10-14

    Obtaining an accurate equation of state (EOS) of polystyrene (CH) is crucial to reliably design inertial confinement fusion (ICF) capsules using CH/CH-based ablators. Thus, with first-principles calculations, we have investigated the extended EOS of CH over a wide range of plasma conditions (ρ = 0.1 to 100 g/cm3 and T = 1,000 to 4,000,000 K). When compared with the widely used SESAME-EOS table, the first-principles equation of state (FPEOS) of CH has shown significant differences in the low-temperature regime, in which strong coupling and electron degeneracy play an essential role in determining plasma properties. Hydrodynamic simulations of cryogenic target implosionsmore » on OMEGA using the FPEOS table of CH have predicted ~5% reduction in implosion velocity and ~30% decrease in neutron yield in comparison with the usual SESAME simulations. This is attributed to the ~10% lower mass ablation rate of CH predicted by FPEOS. Simulations using CH-FPEOS show better agreement with measurements of Hugoniot temperature and scattered lights from ICF implosions.« less

  17. First-principles equation of state of polystyrene and its effect on inertial confinement fusion implosions

    SciTech Connect

    Hu, S. X.; Collins, L. A.; Goncharov, V. N.; Kress, J. D.; McCrory, R. L.; Skupsky, S.

    2015-10-14

    Obtaining an accurate equation of state (EOS) of polystyrene (CH) is crucial to reliably design inertial confinement fusion (ICF) capsules using CH/CH-based ablators. Thus, with first-principles calculations, we have investigated the extended EOS of CH over a wide range of plasma conditions (ρ = 0.1 to 100 g/cm3 and T = 1,000 to 4,000,000 K). When compared with the widely used SESAME-EOS table, the first-principles equation of state (FPEOS) of CH has shown significant differences in the low-temperature regime, in which strong coupling and electron degeneracy play an essential role in determining plasma properties. Hydrodynamic simulations of cryogenic target implosions on OMEGA using the FPEOS table of CH have predicted ~5% reduction in implosion velocity and ~30% decrease in neutron yield in comparison with the usual SESAME simulations. This is attributed to the ~10% lower mass ablation rate of CH predicted by FPEOS. Simulations using CH-FPEOS show better agreement with measurements of Hugoniot temperature and scattered lights from ICF implosions.

  18. Novel free-form hohlraum shape design and optimization for laser-driven inertial confinement fusion

    NASA Astrophysics Data System (ADS)

    Jiang, Shaoen; Jing, Longfei; Huang, Yunbao; Ding, Yongkun

    2014-10-01

    The hohlraum shape attracts considerable attention because there is no successful ignition method for laser-driven inertial confinement fusion at the National Ignition Facility. The available hohlraums are typically designed with simple conic curves, including ellipses, parabolas, arcs, or Lame curves, which allow only a few design parameters for the shape optimization, making it difficult to improve the performance, e.g., the energy coupling efficiency or radiation drive symmetry. A novel free-form hohlraum design and optimization approach based on the non-uniform rational basis spline (NURBS) model is proposed. In the present study, (1) all kinds of hohlraum shapes can be uniformly represented using NURBS, which is greatly beneficial for obtaining the optimal available hohlraum shapes, and (2) such free-form uniform representation enables us to obtain an optimal shape over a large design domain for the hohlraum with a more uniform radiation and higher drive temperature of the fuel capsule. Finally, a hohlraum is optimized and evaluated with respect to the drive temperature and symmetry at the Shenguang III laser facility in China. The drive temperature and symmetry results indicate that such a free-form representation is advantageous over available hohlraum shapes because it can substantially expand the shape design domain so as to obtain an optimal hohlraum with high performance.

  19. On the transport coefficients of hydrogen in the inertial confinement fusion regime

    SciTech Connect

    Lambert, Flavien; Recoules, Vanina; Decoster, Alain; Clerouin, Jean; Desjarlais, Michael

    2011-05-15

    Ab initio molecular dynamics is used to compute the thermal and electrical conductivities of hydrogen from 10 to 160 g cm{sup -3} and temperatures up to 800 eV, i.e., thermodynamical conditions relevant to inertial confinement fusion (ICF). The ionic structure is obtained using molecular dynamics simulations based on an orbital-free treatment for the electrons. The transport properties were computed using ab initio simulations in the DFT/LDA approximation. The thermal and electrical conductivities are evaluated using Kubo-Greenwood formulation. Particular attention is paid to the convergence of electronic transport properties with respect to the number of bands and atoms. These calculations are then used to check various analytical models (Hubbard's, Lee-More's and Ichimaru's) widely used in hydrodynamics simulations of ICF capsule implosions. The Lorenz number, which is the ratio between thermal and electrical conductivities, is also computed and compared to the well-known Wiedemann-Franz law in different regimes ranging from the highly degenerate to the kinetic one. This allows us to deduce electrical conductivity from thermal conductivity for analytical model. We find that the coupling of Hubbard and Spitzer models gives a correct description of the behavior of electrical and thermal conductivities in the whole thermodynamic regime.

  20. Early stage of implosion in inertial confinement fusion: Shock timing and perturbation evolution

    NASA Astrophysics Data System (ADS)

    Goncharov, V. N.; Gotchev, O. V.; Vianello, E.; Boehly, T. R.; Knauer, J. P.; McKenty, P. W.; Radha, P. B.; Regan, S. P.; Sangster, T. C.; Skupsky, S.; Smalyuk, V. A.; Betti, R.; McCrory, R. L.; Meyerhofer, D. D.; Cherfils-Clérouin, C.

    2006-01-01

    Excessive increase in the shell entropy and degradation from spherical symmetry in inertial confinement fusion implosions limit shell compression and could impede ignition. The entropy is controlled by accurately timing shock waves launched into the shell at an early stage of an implosion. The seeding of the Rayleigh-Taylor instability, the main source of the asymmetry growth, is also set at early times during the shock transit across the shell. In this paper we model the shock timing and early perturbation growth of directly driven targets measured on the OMEGA laser system [T. R. Boehly et al., Opt. Commun. 133, 495 (1997)]. By analyzing the distortion evolution, it is shown that one of the main parameters characterizing the growth is the size of the conduction zone Dc, defined as a distance between the ablation front and the laser deposition region. Modes with kDc>1 are stable and experience oscillatory behavior [V. N. Goncharov, Phys. Rev. Lett. 82, 2091 (1999)]. The model shows that the main stabilizing mechanism is the dynamic overpressure due to modulations in the blow-off velocity inside the conduction zone. The long wavelengths with kDc<1 experience growth because of coupled Richtmyer-Meshkov-like and Landau-Darrieus instabilities [L. D. Landau and E. M. Lifshitz, Fluid Mechanics (Pergamon, New York, 1982)]. To match the simulation results with both the shock timing and perturbation growth measurements a new nonlocal thermal transport model is developed and used in hydrocodes.

  1. Mechanism for magnetic field generation and growth in Rayleigh-Taylor unstable inertial confinement fusion plasmas

    SciTech Connect

    Srinivasan, Bhuvana; Tang Xianzhu

    2012-08-15

    Rayleigh-Taylor instabilities (RTI) in inertial confinement fusion (ICF) implosions are expected to generate magnetic fields at the gas-ice interface and at the ice-ablator interface. The focus here is on the gas-ice interface where the temperature gradient is the largest. A Hall-MHD model is used to study the magnetic field generation and growth for 2-D single-mode and multimode RTI in a stratified two-fluid plasma, the two fluids being ions and electrons. Self-generated magnetic fields are observed and these fields grow as the RTI progresses via the {nabla}n{sub e} Multiplication-Sign {nabla}T{sub e} term in the generalized Ohm's law. Srinivasan et al.[Phys. Rev. Lett. 108, 165002 (2012)] present results of the magnetic field generation and growth, and some scaling studies in 2-dimensions. The results presented here study the mechanism behind the magnetic field generation and growth, which is related to fluid vorticity generation by RTI. The magnetic field wraps around the bubbles and spikes and concentrates in flux bundles at the perturbed gas-ice interface where fluid vorticity is large. Additionally, the results of Srinivasan et al.[Phys. Rev. Lett. 108, 165002 (2012)] are described in greater detail. Additional scaling studies are performed to determine the growth of the self-generated magnetic field as a function of density, acceleration, perturbation wavelength, Atwood number, and ion mass.

  2. Inertial Electrostatic Confinement Fusion: The Laser Elevator Solar System Survey for Propellants Abstract

    NASA Technical Reports Server (NTRS)

    Pryor, Wayne

    1999-01-01

    Dr. Wayne Pryor worked on three projects this summer. These were: 1) Inertial Electrostatic Confinement; 2) The Laser Elevator; and 3) Solar System Survey for Propellants Abstract. We Assisted Jon Nadler from Richland Community College in assembling and operating a table-top nuclear fusion reactor. We successfully demonstrated neutron production in a deuterium plasma. Pryor also obtained basic spectroscopic information on the atomic and molecular emissions in the plasma. The second project consisted of the completion of a paper on a novel propulsion concept (due to Tom Meyer of Colorado, the first author): a laser sail that bounces light back to the laser source. Recycling the photons from source to sail perhaps 100-1000 times dramatically improves the energy efficiency of this system, which may become very important for high-velocity missions in the future. Lastly, we compiled a very basic inventory of solar system propellant resources, their locations, and their accessibility. This initial inventory concentrates on sunlight availability, water availability, and the difficulty (delta-velocity requirement and radiation environment) in getting there.

  3. Ion separation effects in mixed-species ablators for inertial-confinement-fusion implosions

    NASA Astrophysics Data System (ADS)

    Amendt, Peter; Bellei, Claudio; Ross, J. Steven; Salmonson, Jay

    2015-02-01

    Recent efforts to demonstrate significant self-heating of the fuel and eventual ignition at the National Ignition Facility make use of plastic (CH) ablators [O. A. Hurricane et al., Phys. Plasmas 21, 056314 (2014), 10.1063/1.4874330]. Mainline simulation techniques for modeling CH capsule implosions treat the ablator as an average-atom fluid and neglect potential species separation phenomena. The mass-ablation process for a mixture is shown to lead to the potential for species separation, parasitic energy loss according to thermodynamic arguments, and reduced rocket efficiency. A generalized plasma barometric formula for a multispecies concentration gradient that includes collisionality and steady flows in spherical geometry is presented. A model based on plasma expansion into a vacuum is used to interpret reported experimental evidence for ablator species separation in an inertial-confinement-fusion target [J. S. Ross et al., Rev. Sci. Instrum. 83, 10E323 (2012)]. The possibility of "runaway" hydrogen ions in the thermoelectric field of the ablation front is conjectured.

  4. Effects of perturbations and radial profiles on ignition of inertial confinement fusion hotspots

    NASA Astrophysics Data System (ADS)

    Taylor, S.; Chittenden, J. P.

    2014-06-01

    Perturbations of inertial confinement fusion hotspots from spherical symmetry cause an increase in the implosion velocity required for ignition, as investigated analytically by [R. Kishony and D. Shvarts, Phys. Plasmas 8, 4925 (2001)] and in numerical studies by many authors. In this paper, we analyse the mechanisms behind this effect by comparing fully 3D fluid simulations of National Ignition Facility targets to a novel analytic model of the thermal energy balance of the hotspot. The analytic model takes into account the radial variation of the state variables within the hotspot and provides an accurate relationship between the hotspot's 0D parameters (ρc, Tc, R , uR, and q) and its heating and cooling rates. The dominant effect of perturbations appears to be an increase in the inflow velocity at the hotspot's surface due to transverse flow of material between perturbation structures, causing premature thermalisation of kinetic energy before the hotspot is fully compressed. In hotspots with a broad perturbation spectrum, thermalisation of energy is inhibited by nonradial motion introduced by mode-mode interaction, reducing the yield further.

  5. X-ray ablation rates in inertial confinement fusion capsule materials

    NASA Astrophysics Data System (ADS)

    Olson, R. E.; Rochau, G. A.; Landen, O. L.; Leeper, R. J.

    2011-03-01

    X-ray ablation rates have been measured in beryllium, copper-doped beryllium, germanium-doped plastic (Ge-doped CH), and diamondlike high density carbon (HDC) for radiation temperatures T in the range of 160-260 eV. In beryllium, the measured ablation rates range from 3 to 12 mg/cm2/ns; in Ge-doped CH, the ablation rates range from 2 to 6 mg/cm2/ns; and for HDC, the rates range from 2 to 9 mg/cm2/ns. The ablation rates follow an approximate T3 dependence and, for T below 230 eV, the beryllium ablation rates are significantly higher than HDC and Ge-doped CH. The corresponding implied ablation pressures are in the range of 20-160 Mbar, scaling as T3.5. The results are found to be well predicted by computational simulations using the physics packages and computational techniques employed in the design of indirect-drive inertial confinement fusion capsules. An iterative rocket model has been developed and used to compare the ablation rate data set to spherical indirect-drive capsule implosion experiments and to confirm the validity of some aspects of proposed full-scale National Ignition Facility ignition capsule designs.

  6. Optimized beryllium target design for indirectly driven inertial confinement fusion experiments on the National Ignition Facility

    SciTech Connect

    Simakov, Andrei N. Wilson, Douglas C.; Yi, Sunghwan A.; Kline, John L.; Batha, Steven H.; Clark, Daniel S.; Milovich, Jose L.; Salmonson, Jay D.

    2014-02-15

    For indirect drive inertial confinement fusion, Beryllium (Be) ablators offer a number of important advantages as compared with other ablator materials, e.g., plastic and high density carbon. In particular, the low opacity and relatively high density of Be lead to higher rocket efficiencies giving a higher fuel implosion velocity for a given X-ray drive; and to higher ablation velocities providing more ablative stabilization and reducing the effect of hydrodynamic instabilities on the implosion performance. Be ablator advantages provide a larger target design optimization space and can significantly improve the National Ignition Facility (NIF) [J. D. Lindl et al., Phys. Plasmas 11, 339 (2004)] ignition margin. Herein, we summarize the Be advantages, briefly review NIF Be target history, and present a modern, optimized, low adiabat, Revision 6 NIF Be target design. This design takes advantage of knowledge gained from recent NIF experiments, including more realistic levels of laser-plasma energy backscatter, degraded hohlraum-capsule coupling, and the presence of cross-beam energy transfer.

  7. Ion separation effects in mixed-species ablators for inertial-confinement-fusion implosions.

    PubMed

    Amendt, Peter; Bellei, Claudio; Ross, J Steven; Salmonson, Jay

    2015-02-01

    Recent efforts to demonstrate significant self-heating of the fuel and eventual ignition at the National Ignition Facility make use of plastic (CH) ablators [O. A. Hurricane et al., Phys. Plasmas 21, 056314 (2014)]. Mainline simulation techniques for modeling CH capsule implosions treat the ablator as an average-atom fluid and neglect potential species separation phenomena. The mass-ablation process for a mixture is shown to lead to the potential for species separation, parasitic energy loss according to thermodynamic arguments, and reduced rocket efficiency. A generalized plasma barometric formula for a multispecies concentration gradient that includes collisionality and steady flows in spherical geometry is presented. A model based on plasma expansion into a vacuum is used to interpret reported experimental evidence for ablator species separation in an inertial-confinement-fusion target [J. S. Ross et al., Rev. Sci. Instrum. 83, 10E323 (2012)]. The possibility of "runaway" hydrogen ions in the thermoelectric field of the ablation front is conjectured. PMID:25768614

  8. Inertial confinement fusion target component fabrication and technology development support: Annual report, October 1, 1997--September 30, 1998

    SciTech Connect

    Gibson, J.

    1998-12-01

    During this period, General Atomics (GA) and their partner Schafer Corporation were assigned 17 formal tasks in support of the Inertial Confinement Fusion (ICF) program and its five laboratories. A portion of the effort on these tasks included providing direct ``On-site Support`` at Lawrence Livermore National Laboratory (LLNL), Los Alamos National Laboratory (LANL), and Sandia National Laboratory Albuquerque (SNLA). They fabricated and delivered over 1,200 hohlraum mandrels and numerous other micromachined components to LLNL, LANL, and SNLA. They produced more than 1,300 glass and plastic target capsules for LLNL, LANL, SNLA, and the University of Rochester/Laboratory for Laser Energetics (UR/LLE). They also delivered nearly 2,000 various target foils and films for Naval Research Lab (NRL) and UR/LLE in FY98. This report describes these target fabrication activities and the target fabrication and characterization development activities that made the deliveries possible. During FY98, great progress was made by the GA/Schafer-UR/LLE-LANL team in the design, procurement, installation, and testing of the OMEGA Cryogenic Target System (OCTS) that will field cryogenic targets on OMEGA. The design phase was concluded for all components of the OCTS and all major components were procured and nearly all were fabricated. Many of the components were assembled and tested, and some have been shipped to UR/LLE. The ICF program is anticipating experiments at the OMEGA laser and the National Ignition Facility (NIF) which will require targets containing cryogenic layered D{sub 2} or deuterium-tritium (DT) fuel. They are part of the National Cryogenic Target Program and support experiments at LLNL and LANL to generate and characterize cryogenic layers for these targets. They also contributed cryogenic support and developed concepts for NIF cryogenic targets. This report summarizes and documents the technical progress made on these tasks.

  9. Confined growth of carbon nanoforms in one-dimension by fusion of anthracene rings inside the pores of MCM-41

    NASA Astrophysics Data System (ADS)

    Bosch-Navarro, Concha; Coronado, Eugenio; Martí-Gastaldo, Carlos; Amorós, Pedro

    2014-06-01

    We report a simple two-step procedure that uses anthracene, a cheap polyaromatic hydrocarbon with low melting point, as a molecular precursor to produce carbon nanoforms (CNFs). First, we describe the chemical synthesis of graphite from the fusion of anthracene rings at relatively low temperature (520 °C) followed by cyclodehydrogenation. Next, we extend this protocol to the synthesis of CNFs by confining the molecular precursor in a mesoporous host like MCM-41. The confined environment favors one-dimensional growth of CNFs with sizes controlled by the pores of the mesoporous host.We report a simple two-step procedure that uses anthracene, a cheap polyaromatic hydrocarbon with low melting point, as a molecular precursor to produce carbon nanoforms (CNFs). First, we describe the chemical synthesis of graphite from the fusion of anthracene rings at relatively low temperature (520 °C) followed by cyclodehydrogenation. Next, we extend this protocol to the synthesis of CNFs by confining the molecular precursor in a mesoporous host like MCM-41. The confined environment favors one-dimensional growth of CNFs with sizes controlled by the pores of the mesoporous host. Electronic supplementary information (ESI) available: Synthesis details, SEM and additional HR-TEM images, FT-IR spectra, EDAX microanalysis and pore distribution of loaded MCM41@anth. See DOI: 10.1039/c3nr06669j

  10. Fusion Safety Program annual report, fiscal year 1994

    SciTech Connect

    Longhurst, G.R.; Cadwallader, L.C.; Dolan, T.J.; Herring, J.S.; McCarthy, K.A.; Merrill, B.J.; Motloch, C.G.; Petti, D.A.

    1995-03-01

    This report summarizes the major activities of the Fusion Safety Program in fiscal year 1994. The Idaho National Engineering Laboratory (INEL) is the designated lead laboratory and Lockheed Idaho Technologies Company is the prime contractor for this program. The Fusion Safety Program was initiated in 1979. Activities are conducted at the INEL, at other DOE laboratories, and at other institutions, including the University of Wisconsin. The technical areas covered in this report include tritium safety, beryllium safety, chemical reactions and activation product release, safety aspects of fusion magnet systems, plasma disruptions, risk assessment failure rate data base development, and thermalhydraulics code development and their application to fusion safety issues. Much of this work has been done in support of the International Thermonuclear Experimental Reactor (ITER). Also included in the report are summaries of the safety and environmental studies performed by the Fusion Safety Program for the Tokamak Physics Experiment and the Tokamak Fusion Test Reactor and of the technical support for commercial fusion facility conceptual design studies. A major activity this year has been work to develop a DOE Technical Standard for the safety of fusion test facilities.

  11. Fusion safety program Annual report, Fiscal year 1995

    SciTech Connect

    Longhurst, G.R.; Cadwallader, L.C.; Carmack, W.J.

    1995-12-01

    This report summarizes the major activities of the Fusion Safety Program in FY-95. The Idaho National Engineering Laboratory (INEL) is the designated lead laboratory, and Lockheed Idaho Technologies Company is the prime contractor for this program. The Fusion Safety Program was initiated in 1979. Activities are conducted at the INEL, at other DOE laboratories, and at other institutions. Among the technical areas covered in this report are tritium safety, beryllium safety, chemical reactions and activation product release, safety aspects of fusion magnet systems, plasma disruptions, risk assessment failure rate database development, and safety code development and application to fusion safety issues. Most of this work has been done in support of the International Thermonuclear Experimental Reactor (ITER). Also included in the report are summaries of the safety and environmental studies performed by the Fusion Safety Program for the Tokamak Physics Experiment and the Tokamak Fusion Test Reactor and the technical support for commercial fusion facility conceptual design studies. A final activity described is work to develop DOE Technical Standards for Safety of Fusion Test Facilities.

  12. Role of supercomputers in magnetic fusion and energy research programs

    SciTech Connect

    Killeen, J.

    1985-06-01

    The importance of computer modeling in magnetic fusion (MFE) and energy research (ER) programs is discussed. The need for the most advanced supercomputers is described, and the role of the National Magnetic Fusion Energy Computer Center in meeting these needs is explained.

  13. Approximate models for the ion-kinetic regime in inertial-confinement-fusion capsule implosions

    SciTech Connect

    Hoffman, Nelson M.; Zimmerman, George B.; Molvig, Kim; Rinderknecht, Hans G.; Rosenberg, Michael J.; Albright, B. J.; Simakov, Andrei N.; Sio, Hong; Zylstra, Alex B.; Johnson, Maria Gatu; Séguin, Fredrick H.; Frenje, Johan A.; Li, C. K.; Petrasso, Richard D.; Higdon, David M.; Srinivasan, Gowri; Glebov, Vladimir Yu.; Stoeckl, Christian; Seka, Wolf; Sangster, T. Craig

    2015-05-19

    “Reduced” (i.e., simplified or approximate) ion-kinetic (RIK) models in radiation-hydrodynamic simulations permit a useful description of inertial-confinement-fusion (ICF) implosions where kinetic deviations from hydrodynamic behavior are important. For implosions in or near the kinetic regime (i.e., when ion mean free paths are comparable to the capsule size), simulations using a RIK model give a detailed picture of the time- and space-dependent structure of imploding capsules, allow an assessment of the relative importance of various kinetic processes during the implosion, enable explanations of past and current observations, and permit predictions of the results of future experiments. The RIK simulation method described here uses moment-based reduced kinetic models for transport of mass, momentum, and energy by long-mean-free-path ions, a model for the decrease of fusion reactivity owing to the associated modification of the ion distribution function, and a model of hydrodynamic turbulent mixing. The transport models are based on local gradient-diffusion approximations for the transport of moments of the ion distribution functions, with coefficients to impose flux limiting or account for transport modification. After calibration against a reference set of ICF implosions spanning the hydrodynamic-to-kinetic transition, the method has useful, quantifiable predictive ability over a broad range of capsule parameter space. Calibrated RIK simulations show that an important contributor to ion species separation in ICF capsule implosions is the preferential flux of longer-mean-free-path species out of the fuel and into the shell, leaving the fuel relatively enriched in species with shorter mean free paths. Also, the transport of ion thermal energy is enhanced in the kinetic regime, causing the fuel region to have a more uniform, lower ion temperature, extending over a larger volume, than implied by clean simulations. We expect that the success of our simple approach

  14. Approximate models for the ion-kinetic regime in inertial-confinement-fusion capsule implosions

    DOE PAGESBeta

    Hoffman, Nelson M.; Zimmerman, George B.; Molvig, Kim; Rinderknecht, Hans G.; Rosenberg, Michael J.; Albright, B. J.; Simakov, Andrei N.; Sio, Hong; Zylstra, Alex B.; Johnson, Maria Gatu; et al

    2015-05-19

    “Reduced” (i.e., simplified or approximate) ion-kinetic (RIK) models in radiation-hydrodynamic simulations permit a useful description of inertial-confinement-fusion (ICF) implosions where kinetic deviations from hydrodynamic behavior are important. For implosions in or near the kinetic regime (i.e., when ion mean free paths are comparable to the capsule size), simulations using a RIK model give a detailed picture of the time- and space-dependent structure of imploding capsules, allow an assessment of the relative importance of various kinetic processes during the implosion, enable explanations of past and current observations, and permit predictions of the results of future experiments. The RIK simulation method describedmore » here uses moment-based reduced kinetic models for transport of mass, momentum, and energy by long-mean-free-path ions, a model for the decrease of fusion reactivity owing to the associated modification of the ion distribution function, and a model of hydrodynamic turbulent mixing. The transport models are based on local gradient-diffusion approximations for the transport of moments of the ion distribution functions, with coefficients to impose flux limiting or account for transport modification. After calibration against a reference set of ICF implosions spanning the hydrodynamic-to-kinetic transition, the method has useful, quantifiable predictive ability over a broad range of capsule parameter space. Calibrated RIK simulations show that an important contributor to ion species separation in ICF capsule implosions is the preferential flux of longer-mean-free-path species out of the fuel and into the shell, leaving the fuel relatively enriched in species with shorter mean free paths. Also, the transport of ion thermal energy is enhanced in the kinetic regime, causing the fuel region to have a more uniform, lower ion temperature, extending over a larger volume, than implied by clean simulations. We expect that the success of our simple

  15. Quantitative studies of kinetic effects in direct- and indirect-drive Inertial Confinement Fusion implosions

    NASA Astrophysics Data System (ADS)

    Rinderknecht, Hans

    2013-10-01

    A comprehensive set of experiments using shock-driven implosions has been conducted to quantitatively study kinetic effects by exploring deviations from hydrodynamic behavior in plasmas relevant to inertial confinement fusion (ICF). Two types of targets were imploded at OMEGA to create ~10 keV, ~1022 cm-3 plasmas with conditions comparable to the incipient hotspot in ignition designs: thin-glass targets filled with mixtures of D2 and 3He gas; and thin deuterated-plastic shells filled with 3He. In the thin-glass experiments, the gas pressure was varied from 1 to 25 atm to scan the ion-mean-free path in the plasma at shock burn. The observed nuclear yields and temperatures deviated more strongly from hydrodynamic predictions as the ion-mean-free path increased to the order of the plasma size. This result provides the first direct experimental evidence how kinetic effects impact yields and ion temperature. The ratio of D to 3He was also varied while maintaining the fuel mass density. As the D fraction was reduced, the DD and D3He fusion products displayed an anomalous yield reduction. Separation of the D and 3He ion species across the strong (Mach ~10) shock-front will be discussed as the likely cause of this result. Finally, thin-CD shells filled with 3He produced significantly more D3He-protons when imploded than is explained by hydrodynamic mix models. This result suggests a kinetic form of mix dominates at the strongly-shocked shell-gas interface. This work was performed in collaboration with C. Li, M. Rosenberg, A. Zylstra, H. Sio, M. Gatu Johnson, F. Séguin, J. Frenje, and R. Petrasso (MIT), V. Glebov, C. Stoeckl, J. Delettrez, and C. Sangster (LLE), J. Pino, P. Amendt, C. Bellei, and S. Wilks (LLNL), G. Kagan, N. Hoffmann and K. Molvig (LANL), and A. Nikroo (GA) and was supported in part by the NLUF, FSC/UR, U.S. DOE, LLNL and LLE.

  16. Approximate models for the ion-kinetic regime in inertial-confinement-fusion capsule implosions

    NASA Astrophysics Data System (ADS)

    Hoffman, Nelson M.; Zimmerman, George B.; Molvig, Kim; Rinderknecht, Hans G.; Rosenberg, Michael J.; Albright, B. J.; Simakov, Andrei N.; Sio, Hong; Zylstra, Alex B.; Gatu Johnson, Maria; Séguin, Fredrick H.; Frenje, Johan A.; Li, C. K.; Petrasso, Richard D.; Higdon, David M.; Srinivasan, Gowri; Glebov, Vladimir Yu.; Stoeckl, Christian; Seka, Wolf; Sangster, T. Craig

    2015-05-01

    "Reduced" (i.e., simplified or approximate) ion-kinetic (RIK) models in radiation-hydrodynamic simulations permit a useful description of inertial-confinement-fusion (ICF) implosions where kinetic deviations from hydrodynamic behavior are important. For implosions in or near the kinetic regime (i.e., when ion mean free paths are comparable to the capsule size), simulations using a RIK model give a detailed picture of the time- and space-dependent structure of imploding capsules, allow an assessment of the relative importance of various kinetic processes during the implosion, enable explanations of past and current observations, and permit predictions of the results of future experiments. The RIK simulation method described here uses moment-based reduced kinetic models for transport of mass, momentum, and energy by long-mean-free-path ions, a model for the decrease of fusion reactivity owing to the associated modification of the ion distribution function, and a model of hydrodynamic turbulent mixing. The transport models are based on local gradient-diffusion approximations for the transport of moments of the ion distribution functions, with coefficients to impose flux limiting or account for transport modification. After calibration against a reference set of ICF implosions spanning the hydrodynamic-to-kinetic transition, the method has useful, quantifiable predictive ability over a broad range of capsule parameter space. Calibrated RIK simulations show that an important contributor to ion species separation in ICF capsule implosions is the preferential flux of longer-mean-free-path species out of the fuel and into the shell, leaving the fuel relatively enriched in species with shorter mean free paths. Also, the transport of ion thermal energy is enhanced in the kinetic regime, causing the fuel region to have a more uniform, lower ion temperature, extending over a larger volume, than implied by clean simulations. We expect that the success of our simple approach

  17. VISTA -- A Vehicle for Interplanetary Space Transport Application Powered by Inertial Confinement Fusion

    SciTech Connect

    Orth, C D

    2005-03-31

    Inertial Confinement Fusion (ICF) is an ideal technology to power self-contained single-stage piloted (manned) spacecraft within the solar system because of its inherently high power/mass ratios and high specific impulses (i.e., high exhaust velocities). These technological advantages are retained when ICF is utilized with a magnetic thrust chamber, which avoids the plasma thermalization and resultant degradation of specific impulse that are unavoidable with the use of mechanical thrust chambers. We started with Rod Hyde's 1983 description of an ICF-powered engine concept using a magnetic thrust chamber, and conducted a more detailed systems study to develop a viable, realistic, and defensible spacecraft concept based on ICF technology projected to be available in the first half of the 21st century. The results include an entirely new conical spacecraft conceptual design utilizing near-existing radiator technology. We describe the various vehicle systems for this new concept, estimate the missions performance capabilities for general missions to the planets within the solar system, and describe in detail the performance for the baseline mission of a piloted roundtrip to Mars with a 100-ton payload. For this mission, we show that roundtrips totaling {ge}145 days are possible with advanced DT fusion technology and a total (wet) spacecraft mass of about 6000 metric tons. Such short-duration missions are advantageous to minimize the known cosmic-radiation hazards to astronauts, and are even more important to minimize the physiological deteriorations arising from zero gravity. These ICF-powered missions are considerably faster than those available using chemical or nuclear-electric-propulsion technologies with minimum-mass vehicle configurations. VISTA also offers onboard artificial gravity and propellant-based shielding from cosmic rays, thus reducing the known hazards and physiological deteriorations to insignificant levels. We emphasize, however, that the degree to

  18. Detailed high-resolution three-dimensional simulations of OMEGA separated reactants inertial confinement fusion experiments

    NASA Astrophysics Data System (ADS)

    Haines, Brian M.; Grim, Gary P.; Fincke, James R.; Shah, Rahul C.; Forrest, Chad J.; Silverstein, Kevin; Marshall, Frederic J.; Boswell, Melissa; Fowler, Malcolm M.; Gore, Robert A.; Hayes-Sterbenz, Anna C.; Jungman, Gerard; Klein, Andreas; Rundberg, Robert S.; Steinkamp, Michael J.; Wilhelmy, Jerry B.

    2016-07-01

    We present results from the comparison of high-resolution three-dimensional (3D) simulations with data from the implosions of inertial confinement fusion capsules with separated reactants performed on the OMEGA laser facility. Each capsule, referred to as a "CD Mixcap," is filled with tritium and has a polystyrene (CH) shell with a deuterated polystyrene (CD) layer whose burial depth is varied. In these implosions, fusion reactions between deuterium and tritium ions can occur only in the presence of atomic mix between the gas fill and shell material. The simulations feature accurate models for all known experimental asymmetries and do not employ any adjustable parameters to improve agreement with experimental data. Simulations are performed with the RAGE radiation-hydrodynamics code using an Implicit Large Eddy Simulation (ILES) strategy for the hydrodynamics. We obtain good agreement with the experimental data, including the DT/TT neutron yield ratios used to diagnose mix, for all burial depths of the deuterated shell layer. Additionally, simulations demonstrate good agreement with converged simulations employing explicit models for plasma diffusion and viscosity, suggesting that the implicit sub-grid model used in ILES is sufficient to model these processes in these experiments. In our simulations, mixing is driven by short-wavelength asymmetries and longer-wavelength features are responsible for developing flows that transport mixed material towards the center of the hot spot. Mix material transported by this process is responsible for most of the mix (DT) yield even for the capsule with a CD layer adjacent to the tritium fuel. Consistent with our previous results, mix does not play a significant role in TT neutron yield degradation; instead, this is dominated by the displacement of fuel from the center of the implosion due to the development of turbulent instabilities seeded by long-wavelength asymmetries. Through these processes, the long

  19. Simultaneous usage of pinhole and penumbral apertures for imaging small scale neutron sources from inertial confinement fusion experiments.

    PubMed

    Guler, N; Volegov, P; Danly, C R; Grim, G P; Merrill, F E; Wilde, C H

    2012-10-01

    Inertial confinement fusion experiments at the National Ignition Facility are designed to understand the basic principles of creating self-sustaining fusion reactions by laser driven compression of deuterium-tritium (DT) filled cryogenic plastic capsules. The neutron imaging diagnostic provides information on the distribution of the central fusion reaction region and the surrounding DT fuel by observing neutron images in two different energy bands for primary (13-17 MeV) and down-scattered (6-12 MeV) neutrons. From this, the final shape and size of the compressed capsule can be estimated and the symmetry of the compression can be inferred. These experiments provide small sources with high yield neutron flux. An aperture design that includes an array of pinholes and penumbral apertures has provided the opportunity to image the same source with two different techniques. This allows for an evaluation of these different aperture designs and reconstruction algorithms. PMID:23126842

  20. Alternative hot spot formation techniques using liquid deuterium-tritium layer inertial confinement fusion capsules

    SciTech Connect

    Olson, R. E.; Leeper, R. J.

    2013-09-15

    The baseline DT ice layer inertial confinement fusion (ICF) ignition capsule design requires a hot spot convergence ratio of ∼34 with a hot spot that is formed from DT mass originally residing in a very thin layer at the inner DT ice surface. In the present paper, we propose alternative ICF capsule designs in which the hot spot is formed mostly or entirely from mass originating within a spherical volume of DT vapor. Simulations of the implosion and hot spot formation in two DT liquid layer ICF capsule concepts—the DT wetted hydrocarbon (CH) foam concept and the “fast formed liquid” (FFL) concept—are described and compared to simulations of standard DT ice layer capsules. 1D simulations are used to compare the drive requirements, the optimal shock timing, the radial dependence of hot spot specific energy gain, and the hot spot convergence ratio in low vapor pressure (DT ice) and high vapor pressure (DT liquid) capsules. 2D simulations are used to compare the relative sensitivities to low-mode x-ray flux asymmetries in the DT ice and DT liquid capsules. It is found that the overall thermonuclear yields predicted for DT liquid layer capsules are less than yields predicted for DT ice layer capsules in simulations using comparable capsule size and absorbed energy. However, the wetted foam and FFL designs allow for flexibility in hot spot convergence ratio through the adjustment of the initial cryogenic capsule temperature and, hence, DT vapor density, with a potentially improved robustness to low-mode x-ray flux asymmetry.

  1. First-principles investigations on ionization and thermal conductivity of polystyrene for inertial confinement fusion applications

    NASA Astrophysics Data System (ADS)

    Hu, S. X.; Collins, L. A.; Goncharov, V. N.; Kress, J. D.; McCrory, R. L.; Skupsky, S.

    2016-04-01

    Using quantum molecular-dynamics (QMD) methods based on the density functional theory, we have performed first-principles investigations of the ionization and thermal conductivity of polystyrene (CH) over a wide range of plasma conditions (ρ = 0.5 to 100 g/cm3 and T = 15 625 to 500 000 K). The ionization data from orbital-free molecular-dynamics calculations have been fitted with a "Saha-type" model as a function of the CH plasma density and temperature, which gives an increasing ionization as the CH density increases even at low temperatures (T < 50 eV). The orbital-free molecular dynamics method is only used to gauge the average ionization behavior of CH under the average-atom model in conjunction with the pressure-matching mixing rule. The thermal conductivities (κQMD) of CH, derived directly from the Kohn-Sham molecular-dynamics calculations, are then analytically fitted with a generalized Coulomb logarithm [(lnΛ)QMD] over a wide range of plasma conditions. When compared with the traditional ionization and thermal conductivity models used in radiation-hydrodynamics codes for inertial confinement fusion simulations, the QMD results show a large difference in the low-temperature regime in which strong coupling and electron degeneracy play an essential role in determining plasma properties. Hydrodynamic simulations of cryogenic deuterium-tritium targets with CH ablators on OMEGA and the National Ignition Facility using the QMD-derived ionization and thermal conductivity of CH have predicted ˜20% variation in target performance in terms of hot-spot pressure and neutron yield (gain) with respect to traditional model simulations.

  2. Alternative hot spot formation techniques using liquid deuterium-tritium layer inertial confinement fusion capsules

    NASA Astrophysics Data System (ADS)

    Olson, R. E.; Leeper, R. J.

    2013-09-01

    The baseline DT ice layer inertial confinement fusion (ICF) ignition capsule design requires a hot spot convergence ratio of ˜34 with a hot spot that is formed from DT mass originally residing in a very thin layer at the inner DT ice surface. In the present paper, we propose alternative ICF capsule designs in which the hot spot is formed mostly or entirely from mass originating within a spherical volume of DT vapor. Simulations of the implosion and hot spot formation in two DT liquid layer ICF capsule concepts—the DT wetted hydrocarbon (CH) foam concept and the "fast formed liquid" (FFL) concept—are described and compared to simulations of standard DT ice layer capsules. 1D simulations are used to compare the drive requirements, the optimal shock timing, the radial dependence of hot spot specific energy gain, and the hot spot convergence ratio in low vapor pressure (DT ice) and high vapor pressure (DT liquid) capsules. 2D simulations are used to compare the relative sensitivities to low-mode x-ray flux asymmetries in the DT ice and DT liquid capsules. It is found that the overall thermonuclear yields predicted for DT liquid layer capsules are less than yields predicted for DT ice layer capsules in simulations using comparable capsule size and absorbed energy. However, the wetted foam and FFL designs allow for flexibility in hot spot convergence ratio through the adjustment of the initial cryogenic capsule temperature and, hence, DT vapor density, with a potentially improved robustness to low-mode x-ray flux asymmetry.

  3. A new ignition hohlraum design for indirect-drive inertial confinement fusion

    NASA Astrophysics Data System (ADS)

    Li, Xin; Wu, Chang-Shu; Dai, Zhen-Sheng; Zheng, Wu-Di; Gu, Jian-Fa; Gu, Pei-Jun; Zou, Shi-Yang; Liu, Jie; Zhu, Shao-Ping

    2016-08-01

    In this paper, a six-cylinder-port hohlraum is proposed to provide high symmetry flux on capsule. It is designed to ignite a capsule with 1.2-mm radius in indirect-drive inertial confinement fusion (ICF). Flux symmetry and laser energy are calculated by using three-dimensional view factor method and laser energy balance in hohlraum. Plasma conditions are analyzed based on the two-dimensional radiation-hydrodynamic simulations. There is no Y lm (l ⩽ 4) asymmetry in the six-cylinder-port hohlraum when the influences of laser entrance holes (LEHs) and laser spots cancel each other out with suitable target parameters. A radiation drive with 300 eV and good flux symmetry can be achieved by using a laser energy of 2.3 MJ and peak power of 500 TW. According to the simulations, the electron temperature and the electron density on the wall of laser cone are high and low, respectively, which are similar to those of outer cones in the hohlraums on National Ignition Facility (NIF). And the laser intensity is also as low as those of NIF outer cones. So the backscattering due to laser plasma interaction (LPI) is considered to be negligible. The six-cyliner-port hohlraum could be superior to the traditional cylindrical hohlraum and the octahedral hohlraum in both higher symmetry and lower backscattering without supplementary technology at an acceptable laser energy level. It is undoubted that the hohlraum will add to the diversity of ICF approaches. Project supported by the National Natural Science Foundation of China (Grant Nos. 11435011 and 11575034).

  4. A measurable Lawson criterion and hydro-equivalent curves for inertial confinement fusion

    SciTech Connect

    Zhou, C. D.; Betti, R.

    2008-10-15

    It is shown that the ignition condition (Lawson criterion) for inertial confinement fusion (ICF) can be cast in a form dependent on the only two parameters of the compressed fuel assembly that can be measured with existing techniques: the hot spot ion temperature (T{sub i}{sup h}) and the total areal density ({rho}R{sub tot}), which includes the cold shell contribution. A marginal ignition curve is derived in the {rho}R{sub tot}, T{sub i}{sup h} plane and current implosion experiments are compared with the ignition curve. On this plane, hydrodynamic equivalent curves show how a given implosion would perform with respect to the ignition condition when scaled up in the laser-driver energy. For 3<{sub n}<6 keV, an approximate form of the ignition condition (typical of laser-driven ICF) is {sub n}{sup 2.6}{center_dot}<{rho}R{sub tot}>{sub n}>50 keV{sup 2.6}{center_dot} g/cm{sup 2}, where <{rho}R{sub tot}>{sub n} and {sub n} are the burn-averaged total areal density and hot spot ion temperature, respectively. Both quantities are calculated without accounting for the alpha-particle energy deposition. Such a criterion can be used to determine how surrogate D{sub 2} and subignited DT target implosions perform with respect to the one-dimensional ignition threshold.

  5. The mitigating effect of magnetic fields on Rayleigh-Taylor unstable inertial confinement fusion plasmas

    SciTech Connect

    Srinivasan, Bhuvana; Tang, Xian-Zhu

    2013-05-15

    Rayleigh-Taylor (RT) instabilities at interfaces of disparate mass densities have long been known to generate magnetic fields during inertial confinement fusion implosions. An externally applied magnetic field can also be efficiently amplified by RT instabilities. The focus here is on magnetic field generation and amplification at the gas-ice interface which is RT unstable during the deceleration phase of the implosion. RT instabilities lead to undesirable mix of hot and cold plasmas which enhances thermal energy loss and tends to produce a more massive warm-spot instead of a hot-spot. Two mechanisms are shown here to mitigate the thermal energy loss from the hot-spot. The first mechanism is the reduction of electron thermal conductivity with interface-aligned magnetic fields. This can occur through self-generated magnetic fields via the Biermann battery effect as well as through externally applied magnetic fields that undergo an exponential growth via the stretch-and-fold magnetohydrodynamic dynamo. Self-generated magnetic fields during RT evolution can result in a factor of 2−10 decrease in the electron thermal conductivity at the gas-ice interface, while externally applied magnetic fields that are compressed to 6–1000 T at the onset of deceleration (corresponding to pre-implosion external fields of 0.06–10 T) could result in a factor of 2–500 reduction in electron thermal conductivity at the gas-ice interface. The second mechanism to mitigate thermal energy loss from the hot-spot is to decrease the interface mixing area between the hot and cold plasmas. This is achieved through large external magnetic fields of 1000 T at the onset of deceleration which damp short-wavelength RT modes and long-wavelength Kelvin-Helmholtz modes thus significantly slowing the RT growth and reducing mix.

  6. Fusion of ranging data from robot teams operating in confined areas

    NASA Astrophysics Data System (ADS)

    Lyons, Damian M.; Shrestha, Karma; Liu, Tsung-Ming

    2013-05-01

    We address the problem of fusing laser ranging data from multiple mobile robots that are surveying an area as part of a robot search and rescue or area surveillance mission. We are specifically interested in the case where members of the robot team are working in close proximity to each other. The advantage of this teamwork is that it greatly speeds up the surveying process; the area can be quickly covered even when the robots use a random motion exploration approach. However, the disadvantage of the close proximity is that it is possible, and even likely, that the laser ranging data from one robot include many depth readings caused by another robot. We refer to this as mutual interference. Using a team of two Pioneer 3-AT robots with tilted SICK LMS-200 laser sensors, we evaluate several techniques for fusing the laser ranging information so as to eliminate the mutual interference. There is an extensive literature on the mapping and localization aspect of this problem. Recent work on mapping has begun to address dynamic or transient objects. Our problem differs from the dynamic map problem in that we look at one kind of transient map feature, other robots, and we know that we wish to completely eliminate the feature. We present and evaluate three different approaches to the map fusion problem: a robot-centric approach, based on estimating team member locations; a map-centric approach, based on inspecting local regions of the map, and a combination of both approaches. We show results for these approaches for several experiments for a two robot team operating in a confined indoor environment .

  7. SIRIUS-P: An inertially confined direct drive laser fusion power reactor

    SciTech Connect

    Sviatoslavsky, I.N.; Kulcinski, G.L.; Moses, G.A.; Bruggink, D.; Engelstad, R.L.; Khater, H.Y.; Larsen, E.M.; Lovell, E.G.; MacFarlane, J.J.; Mogahed, E.A.; Peterson, R.R.; Sawan, M.E.; Wang, P.; Wittenberg, L.J.

    1993-03-01

    The SIRIUS-P conceptual design study is of a 1000 MWe laser driven inertial confinement fusion power reactor utilizing near symmetric illumination of direct drive targets. The reference driver is a KrF laser; however, any other laser capable of delivering short wavelength energy can be substituted. Sixty beams providing a total of 3.4 MJ of energy are used at a repetition rate of 6.7 Hz and a target gain of 118. The spherical chamber has an internal diameter of 6.5 m and consists of two independent components, a first wall assembly fabricated from a c/c composite and a blanket assembly made of SiC. First wall protection is provided by a xenon buffer gas at a pressure of 0.5 torr. The chamber is cooled by a flowing granular bed of solid ceramic material, TiO[sub 2] for the first wall assembly and Li[sub 2]O for the blanket assembly. The chamber is housed within a 42 m radius cylindrical reactor building which is 86 m high and which shares the same vacuum space as the chamber. All the laser beams are brought in at the bottom of the building, first onto a dielectrically coated final focusing mirror and finally onto a metallic grazing incidence mirror which reflects them into the chamber through beam ports open to the building. Neutron traps behind the grazing incidence mirrors are used to prolong the lifetimes of the final focusing optics. The nominal cost of electricity from this system is 65 mills/kwh assuming an 8% interest rate on capital.

  8. SIRIUS-P: An inertially confined direct drive laser fusion power reactor

    SciTech Connect

    Sviatoslavsky, I.N.; Kulcinski, G.L.; Moses, G.A.; Bruggink, D.; Engelstad, R.L.; Khater, H.Y.; Larsen, E.M.; Lovell, E.G.; MacFarlane, J.J.; Mogahed, E.A.; Peterson, R.R.; Sawan, M.E.; Wang, P.; Wittenberg, L.J.

    1993-03-01

    The SIRIUS-P conceptual design study is of a 1000 MWe laser driven inertial confinement fusion power reactor utilizing near symmetric illumination of direct drive targets. The reference driver is a KrF laser; however, any other laser capable of delivering short wavelength energy can be substituted. Sixty beams providing a total of 3.4 MJ of energy are used at a repetition rate of 6.7 Hz and a target gain of 118. The spherical chamber has an internal diameter of 6.5 m and consists of two independent components, a first wall assembly fabricated from a c/c composite and a blanket assembly made of SiC. First wall protection is provided by a xenon buffer gas at a pressure of 0.5 torr. The chamber is cooled by a flowing granular bed of solid ceramic material, TiO{sub 2} for the first wall assembly and Li{sub 2}O for the blanket assembly. The chamber is housed within a 42 m radius cylindrical reactor building which is 86 m high and which shares the same vacuum space as the chamber. All the laser beams are brought in at the bottom of the building, first onto a dielectrically coated final focusing mirror and finally onto a metallic grazing incidence mirror which reflects them into the chamber through beam ports open to the building. Neutron traps behind the grazing incidence mirrors are used to prolong the lifetimes of the final focusing optics. The nominal cost of electricity from this system is 65 mills/kwh assuming an 8% interest rate on capital.

  9. Fusion programs in Applied Plasma Physics. Contract extension report, October 1, 1991--January 31, 1992

    SciTech Connect

    Not Available

    1992-07-01

    The Applied Plasma Physics (APP) program at General Atomics (GA) described here includes four major elements: (a) Applied Plasma Physics Theory Program, (b) Alpha Particle Diagnostic, (c) Edge and Current Density Diagnostic, and (d) Fusion User Service Center (USC). The objective of the APP theoretical plasma physics research at GA is to support the DIII-D and other tokamak experiments and to significantly advance our ability to design a commercially-attractive fusion reactor. We categorize our efforts in three areas: magnetohydrodynamic (MHD) equilibria and stability; plasma transport with emphasis on H-mode, divertor, and boundary physics; and radio frequency (rf). The objective of the APP alpha particle diagnostic is to develop diagnostics of fast confined alpha particles using the interactions with the ablation cloud surrounding injected pellets and to develop diagnostic systems for reacting and ignited plasmas. The objective of the APP edge and current density diagnostic is to first develop a lithium beam diagnostic system for edge fluctuation studies on the Texas Experimental Tokamak (TEXT). The objective of the Fusion USC is to continue to provide maintenance and programming support to computer users in the GA fusion community. The detailed progress of each separate program covered in this report period is described in the following sections.

  10. Presentation at FTP: A review. [ORNL Fusion Energy Program

    SciTech Connect

    Sheffield, J.

    1987-01-01

    This series of vugraphs presents some information concerning ORNL's involvement in the fusion energy research program. Recent and future experiments are named, and a rough estimate of funding is given. (JDH)

  11. Fusion programs in applied plasma physics and development and technology at GA Technologies, Inc.

    NASA Astrophysics Data System (ADS)

    Overskei, D. O.

    1988-01-01

    Research carried out by GA for the Department of Energy Office of Fusion Energy provides key information and insight necessary for the development of fusion power systems. Highlights of the fusion theory effort described in this report include progress in numerical simulations of turbulent transport in tokamak plasmas, extension of novel theories of the H-mode, development and application of advanced codes for evaluating ECRF current drive efficiency, and new understanding and techniques for dealing with high beta tokamak equilibria. Experimental plasma research efforts are addresssing several important issues in fusion research. Neutron and alpha particle spectroscopy and triton confinement diagnostics are being developed to enable fusion researchers to understand alpha particle confinement and slowdown in burning plasmas. Development of Li beam diagnostic systems continued and has shown a capability for measuring both magnetic field pitch angle and relative current density profiles. Experiments on Ergodic Magnetic Divertor (EMD) phenomena on the Texas Experimental Tokamak (TEXT) continued to demonstrate low plasma edge temperatures and impurity reduction that make the concept attractive for reactor applications. GA led efforts continuing the Resonant Island Divertor (RID) experiments on TEXT using the EMD as a controlled magnetic perturbation. Research carried out in GA's Development and Technology programs included reactor systems design studies, and development of ferritic steels suitable for use as a structural material in fusion reactors. In the reactor systems design area, GA participated in the TITAN Reserved Field Pinch (RFP) Reactor Design Study. GA is responsible for project operation, safety design and analysis, and blanket shield neutronics calculations for this study.

  12. Neutron Transport and Nuclear Burnup Analysis for the Laser Inertial Confinement Fusion-Fission Energy (LIFE) Engine

    SciTech Connect

    Kramer, K J; Latkowski, J F; Abbott, R P; Boyd, J K; Powers, J J; Seifried, J E

    2008-10-24

    Lawrence Livermore National Laboratory is currently developing a hybrid fusion-fission nuclear energy system, called LIFE, to generate power and burn nuclear waste. We utilize inertial confinement fusion to drive a subcritical fission blanket surrounding the fusion chamber. It is composed of TRISO-based fuel cooled by the molten salt flibe. Low-yield (37.5 MJ) targets and a repetition rate of 13.3 Hz produce a 500 MW fusion source that is coupled to the subcritical blanket, which provides an additional gain of 4-8, depending on the fuel. In the present work, we describe the neutron transport and nuclear burnup analysis. We utilize standard analysis tools including, the Monte Carlo N-Particle (MCNP) transport code, ORIGEN2 and Monteburns to perform the nuclear design. These analyses focus primarily on a fuel composed of depleted uranium not requiring chemical reprocessing or enrichment. However, other fuels such as weapons grade plutonium and highly-enriched uranium are also under consideration. In addition, we have developed a methodology using {sup 6}Li as a burnable poison to replace the tritium burned in the fusion targets and to maintain constant power over the lifetime of the engine. The results from depleted uranium analyses suggest up to 99% burnup of actinides is attainable while maintaining full power at 2GW for more than five decades.

  13. Fusion safety program annual report fiscal year 1997

    SciTech Connect

    Longhurst, G.R.; Anderl, R.A.; Cadwallader, L.C.

    1998-01-01

    This report summarizes the major activities of the Fusion Safety Program in FY 1997. The Idaho National Engineering and Environmental Laboratory (INEEL) is the designated lead laboratory, and Lockheed Martin Idaho Technologies Company is the prime contractor for this program. The Fusion Safety Program was initiated in FY 1979 to perform research and develop data needed to ensure safety in fusion facilities. Activities include experiments, analysis, code development and application, and other forms of research. These activities are conducted at the INEEL, different DOE laboratories, and other institutions. The technical areas covered in this report include chemical reactions and activation product release, tritium safety, risk assessment failure rate database development, and safety code development and application to fusion safety issues. Most of this work has been done in support of the International Thermonuclear Experimental Reactor (ITER) project. Work done for ITER this year has focused on developing the needed information for the Non-site Specific Safety Report (NSSR-2).

  14. The Heavy Ion Fusion Program in the USA

    SciTech Connect

    Bangerter, R.O.

    2000-03-17

    The U.S. Department of Energy has established a new, larger inertial fusion energy program. To manage program growth, we have developed a new inertial fusion energy research and we have established a Virtual National Laboratory for Heavy Ion Fusion. There has been significant technical progress. Improvements in target design have reduced the predicted energy requirements by approximately a factor of two. There have also been important experiments on chamber dynamics and other inertial fusion technologies. The accelerator program has completed a number of small-scale experiments. Experiments with driver-scale beams are being designed -- including experiments with driver-scale ion sources and injectors. Finally we are developing the technologies needed to build a major research facility known as the Integrated Research Experiment (IRE)

  15. Bump evolution driven by the x-ray ablation Richtmyer-Meshkov effect in plastic inertial confinement fusion Ablators

    NASA Astrophysics Data System (ADS)

    Loomis, Eric; Braun, Dave; Batha, Steven H.; Landen, Otto L.

    2013-11-01

    Growth of hydrodynamic instabilities at the interfaces of inertial confinement fusion capsules (ICF) due to ablator and fuel non-uniformities are a primary concern for the ICF program. Recently, observed jetting and parasitic mix into the fuel were attributed to isolated defects on the outer surface of the capsule. Strategies for mitigation of these defects exist, however, they require reduced uncertainties in Equation of State (EOS) models prior to invoking them. In light of this, we have begun a campaign to measure the growth of isolated defects (bumps) due to x-ray ablation Richtmyer-Meshkov in plastic ablators to validate these models. Experiments used hohlraums with radiation temperatures near 70 eV driven by 15 beams from the Omega laser (Laboratory for Laser Energetics, University of Rochester, NY), which sent a ˜1.25Mbar shock into a planar CH target placed over one laser entrance hole. Targets consisted of 2-D arrays of quasi-gaussian bumps (10 microns tall, 34 microns FWHM) deposited on the surface facing into the hohlraum. On-axis radiography with a saran (Cl Heα - 2.76keV) backlighter was used to measure bump evolution prior to shock breakout. Shock speed measurements were also performed to determine target conditions. Simulations using the LEOS 5310 and SESAME 7592 models required the simulated laser power be turned down to 80 and 88%, respectively to match observed shock speeds. Both LEOS 5310 and SESAME 7592 simulations agreed with measured bump areal densities out to 6 ns where ablative RM oscillations were observed in previous laser-driven experiments, but did not occur in the x-ray driven case. The QEOS model, conversely, over predicted shock speeds and under predicted areal density in the bump.

  16. First-principles thermal conductivity of warm-dense deuterium plasmas for inertial confinement fusion applications

    NASA Astrophysics Data System (ADS)

    Hu, S. X.; Collins, L. A.; Boehly, T. R.; Kress, J. D.; Goncharov, V. N.; Skupsky, S.

    2014-04-01

    Thermal conductivity (κ) of both the ablator materials and deuterium-tritium (DT) fuel plays an important role in understanding and designing inertial confinement fusion (ICF) implosions. The extensively used Spitzer model for thermal conduction in ideal plasmas breaks down for high-density, low-temperature shells that are compressed by shocks and spherical convergence in imploding targets. A variety of thermal-conductivity models have been proposed for ICF hydrodynamic simulations of such coupled and degenerate plasmas. The accuracy of these κ models for DT plasmas has recently been tested against first-principles calculations using the quantum molecular-dynamics (QMD) method; although mainly for high densities (ρ > 100 g/cm3), large discrepancies in κ have been identified for the peak-compression conditions in ICF. To cover the wide range of density-temperature conditions undergone by ICF imploding fuel shells, we have performed QMD calculations of κ for a variety of deuterium densities of ρ = 1.0 to 673.518 g/cm3, at temperatures varying from T = 5 × 103 K to T = 8 × 106 K. The resulting κQMD of deuterium is fitted with a polynomial function of the coupling and degeneracy parameters Γ and θ, which can then be used in hydrodynamic simulation codes. Compared with the "hybrid" Spitzer-Lee-More model currently adopted in our hydrocode lilac, the hydrosimulations using the fitted κQMD have shown up to ˜20% variations in predicting target performance for different ICF implosions on OMEGA and direct-drive-ignition designs for the National Ignition Facility (NIF). The lower the adiabat of an imploding shell, the more variations in predicting target performance using κQMD. Moreover, the use of κQMD also modifies the shock conditions and the density-temperature profiles of the imploding shell at early implosion stage, which predominantly affects the final target performance. This is in contrast to the previous speculation that κQMD changes mainly the

  17. Inertial Confinement Fusion quarterly report April-June 1999, volume 9, number 3

    SciTech Connect

    MacGowan, B

    1999-06-01

    enhance significantly our understanding of the details of how radiation and matter interact with one another in contexts relevant both to inertial confinement fusion (ICF) and to other applications. The first of these two articles describes these experiments. The second one describes the application of such radiative heating techniques to development of a ''piston'' for shocklessly accelerating materials. This new experimental technique, first developed on Nova, shows promise as a way to diagnose the development of acceleration-driven hydrodynamic instabilities in the compressible regime, a longstanding ICF problem that is currently only poorly understood.

  18. First-principles opacity table of warm dense deuterium for inertial-confinement-fusion applications.

    PubMed

    Hu, S X; Collins, L A; Goncharov, V N; Boehly, T R; Epstein, R; McCrory, R L; Skupsky, S

    2014-09-01

    Accurate knowledge of the optical properties of a warm dense deuterium-tritium (DT) mixture is important for reliable design of inertial confinement fusion (ICF) implosions using radiation-hydrodynamics simulations. The opacity of a warm dense DT shell essentially determines how much radiation from hot coronal plasmas can be deposited in the DT fuel of an imploding capsule. Even for the simplest species of hydrogen, the accurate calculation of their opacities remains a challenge in the warm-dense matter regime because strong-coupling and quantum effects play an important role in such plasmas. With quantum-molecular-dynamics (QMD) simulations, we have derived a first-principles opacity table (FPOT) of deuterium (and the DT mixture by mass scaling) for a wide range of densities from ρ(D)=0.5 to 673.518g/cm(3) and temperatures from T=5000K up to the Fermi temperature T(F) for each density. Compared with results from the astrophysics opacity table (AOT) currently used in our hydrocodes, the FPOT of deuterium from our QMD calculations has shown a significant increase in opacity for strongly coupled and degenerate plasma conditions by a factor of 3-100 in the ICF-relevant photon-energy range. As conditions approach those of classical plasma, the opacity from the FPOT converges to the corresponding values of the AOT. By implementing the FPOT of deuterium and the DT mixture into our hydrocodes, we have performed radiation-hydrodynamics simulations for low-adiabat cryogenic DT implosions on the OMEGA laser and for direct-drive-ignition designs for the National Ignition Facility. The simulation results using the FPOT show that the target performance (in terms of neutron yield and energy gain) could vary from ∼10% up to a factor of ∼2 depending on the adiabat of the imploding DT capsule; the lower the adiabat, the more variation is seen in the prediction of target performance when compared to the AOT modeling. PMID:25314551

  19. First-principles thermal conductivity of warm-dense deuterium plasmas for inertial confinement fusion applications.

    PubMed

    Hu, S X; Collins, L A; Boehly, T R; Kress, J D; Goncharov, V N; Skupsky, S

    2014-04-01

    Thermal conductivity (κ) of both the ablator materials and deuterium-tritium (DT) fuel plays an important role in understanding and designing inertial confinement fusion (ICF) implosions. The extensively used Spitzer model for thermal conduction in ideal plasmas breaks down for high-density, low-temperature shells that are compressed by shocks and spherical convergence in imploding targets. A variety of thermal-conductivity models have been proposed for ICF hydrodynamic simulations of such coupled and degenerate plasmas. The accuracy of these κ models for DT plasmas has recently been tested against first-principles calculations using the quantum molecular-dynamics (QMD) method; although mainly for high densities (ρ > 100 g/cm3), large discrepancies in κ have been identified for the peak-compression conditions in ICF. To cover the wide range of density-temperature conditions undergone by ICF imploding fuel shells, we have performed QMD calculations of κ for a variety of deuterium densities of ρ = 1.0 to 673.518 g/cm3, at temperatures varying from T = 5 × 103 K to T = 8 × 106 K. The resulting κQMD of deuterium is fitted with a polynomial function of the coupling and degeneracy parameters Γ and θ, which can then be used in hydrodynamic simulation codes. Compared with the "hybrid" Spitzer-Lee-More model currently adopted in our hydrocode lilac, the hydrosimulations using the fitted κQMD have shown up to ∼20% variations in predicting target performance for different ICF implosions on OMEGA and direct-drive-ignition designs for the National Ignition Facility (NIF). The lower the adiabat of an imploding shell, the more variations in predicting target performance using κQMD. Moreover, the use of κQMD also modifies the shock conditions and the density-temperature profiles of the imploding shell at early implosion stage, which predominantly affects the final target performance. This is in contrast to the previous speculation that κQMD changes mainly the

  20. Impact of first-principles properties of deuterium–tritium on inertial confinement fusion target designs

    DOE PAGESBeta

    Hu, S. X.; Goncharov, V. N.; Boehly, T. R.; McCrory, R. L.; Skupsky, S.; Collins, L. A.; Kress, J. D.; Militizer, B.

    2015-04-20

    In this study, a comprehensive knowledge of the properties of high-energy-density plasmas is crucial to understanding and designing low-adiabat, inertial confinement fusion (ICF) implosions through hydrodynamic simulations. Warm-dense-matter (WDM) conditions are routinely accessed by low-adiabat ICF implosions, in which strong coupling and electron degeneracy often play an important role in determining the properties of warm dense plasmas. The WDM properties of deuterium–tritium (DT) mixtures and ablator materials, such as the equation of state, thermal conductivity, opacity, and stopping power, were usually estimated by models in hydro-codes used for ICF simulations. In these models, many-body and quantum effects were only approximatelymore » taken into account in the WMD regime. Moreover, the self-consistency among these models was often missing. To examine the accuracy of these models, we have systematically calculated the static, transport, and optical properties of warm dense DT plasmas, using first-principles (FP) methods over a wide range of densities and temperatures that cover the ICF “path” to ignition. These FP methods include the path-integral Monte Carlo (PIMC) and quantum-molecular dynamics (QMD) simulations, which treat electrons with many-body quantum theory. The first-principles equation-of-state table, thermal conductivities (KQMD), and first principles opacity table of DT have been self-consistently derived from the combined PIMC and QMD calculations. They have been compared with the typical models, and their effects to ICF simulations have been separately examined in previous publications. In this paper, we focus on their combined effects to ICF implosions through hydro-simulations using these FP-based properties of DT in comparison with the usual model simulations. We found that the predictions of ICF neutron yield could change by up to a factor of –2.5; the lower the adiabat of DT capsules, the more variations in hydro

  1. Impact of first-principles properties of deuterium-tritium on inertial confinement fusion target designsa)

    NASA Astrophysics Data System (ADS)

    Hu, S. X.; Goncharov, V. N.; Boehly, T. R.; McCrory, R. L.; Skupsky, S.; Collins, L. A.; Kress, J. D.; Militzer, B.

    2015-05-01

    A comprehensive knowledge of the properties of high-energy-density plasmas is crucial to understanding and designing low-adiabat, inertial confinement fusion (ICF) implosions through hydrodynamic simulations. Warm-dense-matter (WDM) conditions are routinely accessed by low-adiabat ICF implosions, in which strong coupling and electron degeneracy often play an important role in determining the properties of warm dense plasmas. The WDM properties of deuterium-tritium (DT) mixtures and ablator materials, such as the equation of state, thermal conductivity, opacity, and stopping power, were usually estimated by models in hydro-codes used for ICF simulations. In these models, many-body and quantum effects were only approximately taken into account in the WMD regime. Moreover, the self-consistency among these models was often missing. To examine the accuracy of these models, we have systematically calculated the static, transport, and optical properties of warm dense DT plasmas, using first-principles (FP) methods over a wide range of densities and temperatures that cover the ICF "path" to ignition. These FP methods include the path-integral Monte Carlo (PIMC) and quantum-molecular dynamics (QMD) simulations, which treat electrons with many-body quantum theory. The first-principles equation-of-state table, thermal conductivities (κQMD), and first principles opacity table of DT have been self-consistently derived from the combined PIMC and QMD calculations. They have been compared with the typical models, and their effects to ICF simulations have been separately examined in previous publications. In this paper, we focus on their combined effects to ICF implosions through hydro-simulations using these FP-based properties of DT in comparison with the usual model simulations. We found that the predictions of ICF neutron yield could change by up to a factor of ˜2.5; the lower the adiabat of DT capsules, the more variations in hydro-simulations. The FP-based properties of DT

  2. Impact of first-principles properties of deuterium–tritium on inertial confinement fusion target designs

    SciTech Connect

    Hu, S. X. Goncharov, V. N.; Boehly, T. R.; McCrory, R. L.; Skupsky, S.; Collins, L. A.; Kress, J. D.; Militzer, B.

    2015-05-15

    A comprehensive knowledge of the properties of high-energy-density plasmas is crucial to understanding and designing low-adiabat, inertial confinement fusion (ICF) implosions through hydrodynamic simulations. Warm-dense-matter (WDM) conditions are routinely accessed by low-adiabat ICF implosions, in which strong coupling and electron degeneracy often play an important role in determining the properties of warm dense plasmas. The WDM properties of deuterium–tritium (DT) mixtures and ablator materials, such as the equation of state, thermal conductivity, opacity, and stopping power, were usually estimated by models in hydro-codes used for ICF simulations. In these models, many-body and quantum effects were only approximately taken into account in the WMD regime. Moreover, the self-consistency among these models was often missing. To examine the accuracy of these models, we have systematically calculated the static, transport, and optical properties of warm dense DT plasmas, using first-principles (FP) methods over a wide range of densities and temperatures that cover the ICF “path” to ignition. These FP methods include the path-integral Monte Carlo (PIMC) and quantum-molecular dynamics (QMD) simulations, which treat electrons with many-body quantum theory. The first-principles equation-of-state table, thermal conductivities (κ{sub QMD}), and first principles opacity table of DT have been self-consistently derived from the combined PIMC and QMD calculations. They have been compared with the typical models, and their effects to ICF simulations have been separately examined in previous publications. In this paper, we focus on their combined effects to ICF implosions through hydro-simulations using these FP-based properties of DT in comparison with the usual model simulations. We found that the predictions of ICF neutron yield could change by up to a factor of ∼2.5; the lower the adiabat of DT capsules, the more variations in hydro-simulations. The FP

  3. Impact of first-principles properties of deuterium–tritium on inertial confinement fusion target designs

    SciTech Connect

    Hu, S. X.; Goncharov, V. N.; Boehly, T. R.; McCrory, R. L.; Skupsky, S.; Collins, L. A.; Kress, J. D.; Militizer, B.

    2015-04-20

    In this study, a comprehensive knowledge of the properties of high-energy-density plasmas is crucial to understanding and designing low-adiabat, inertial confinement fusion (ICF) implosions through hydrodynamic simulations. Warm-dense-matter (WDM) conditions are routinely accessed by low-adiabat ICF implosions, in which strong coupling and electron degeneracy often play an important role in determining the properties of warm dense plasmas. The WDM properties of deuterium–tritium (DT) mixtures and ablator materials, such as the equation of state, thermal conductivity, opacity, and stopping power, were usually estimated by models in hydro-codes used for ICF simulations. In these models, many-body and quantum effects were only approximately taken into account in the WMD regime. Moreover, the self-consistency among these models was often missing. To examine the accuracy of these models, we have systematically calculated the static, transport, and optical properties of warm dense DT plasmas, using first-principles (FP) methods over a wide range of densities and temperatures that cover the ICF “path” to ignition. These FP methods include the path-integral Monte Carlo (PIMC) and quantum-molecular dynamics (QMD) simulations, which treat electrons with many-body quantum theory. The first-principles equation-of-state table, thermal conductivities (KQMD), and first principles opacity table of DT have been self-consistently derived from the combined PIMC and QMD calculations. They have been compared with the typical models, and their effects to ICF simulations have been separately examined in previous publications. In this paper, we focus on their combined effects to ICF implosions through hydro-simulations using these FP-based properties of DT in comparison with the usual model simulations. We found that the predictions of ICF neutron yield could change by up to a factor of –2.5; the lower the adiabat of DT capsules, the more variations in hydro

  4. Impact of first-principles properties of deuterium–tritium on inertial confinement fusion target designsa)

    DOE PAGESBeta

    Hu, S. X.; Goncharov, V. N.; Boehly, T. R.; McCrory, R. L.; Skupsky, S.; Collins, L. A.; Kress, J. D.; Militizer, B.

    2015-04-20

    In this study, a comprehensive knowledge of the properties of high-energy-density plasmas is crucial to understanding and designing low-adiabat, inertial confinement fusion (ICF) implosions through hydrodynamic simulations. Warm-dense-matter (WDM) conditions are routinely accessed by low-adiabat ICF implosions, in which strong coupling and electron degeneracy often play an important role in determining the properties of warm dense plasmas. The WDM properties of deuterium–tritium (DT) mixtures and ablator materials, such as the equation of state, thermal conductivity, opacity, and stopping power, were usually estimated by models in hydro-codes used for ICF simulations. In these models, many-body and quantum effects were only approximatelymore » taken into account in the WMD regime. Moreover, the self-consistency among these models was often missing. To examine the accuracy of these models, we have systematically calculated the static, transport, and optical properties of warm dense DT plasmas, using first-principles (FP) methods over a wide range of densities and temperatures that cover the ICF “path” to ignition. These FP methods include the path-integral Monte Carlo (PIMC) and quantum-molecular dynamics (QMD) simulations, which treat electrons with many-body quantum theory. The first-principles equation-of-state table, thermal conductivities (KQMD), and first principles opacity table of DT have been self-consistently derived from the combined PIMC and QMD calculations. They have been compared with the typical models, and their effects to ICF simulations have been separately examined in previous publications. In this paper, we focus on their combined effects to ICF implosions through hydro-simulations using these FP-based properties of DT in comparison with the usual model simulations. We found that the predictions of ICF neutron yield could change by up to a factor of –2.5; the lower the adiabat of DT capsules, the more variations in hydro

  5. Inertial confinement fusion. Quarterly report, July--September 1993: Volume 3, No. 4

    SciTech Connect

    Sacks, R.A.; Murphy, P.W.; Schleich, D.P.

    1993-12-31

    This report discusses the following research: Diode-pumped solid- state-laser driver for inertial fusion energy power plants; Longitudinal beam dynamics in heavy ion fusion accelerators; Design of the ion sources for heavy ion fusion; Measurement of electron density in laser-produced plasma with a soft x-ray moire deflectometer; and Analysis of weakly nonlinear three-dimensional Rayleigh-Taylor instability growth.

  6. BOOK REVIEW: Inertial confinement fusion: The quest for ignition and energy gain using indirect drive

    NASA Astrophysics Data System (ADS)

    Yamanaka, C.

    1999-06-01

    Inertial confinement fusion (ICF) is an alternative way to control fusion which is based on scaling down a thermonuclear explosion to a small size, applicable for power production, a kind of thermonuclear internal combustion engine. This book extends many interesting topics concerning the research and development on ICF of the last 25 years. It provides a systematic development of the physics basis and also various experimental data on radiation driven implosion. This is a landmark treatise presented at the right time. It is based on the article ``Development of the indirect-drive approach to inertial confinement fusion and the target physics basis for ignition and gain'' by J.D. Lindl, published in Physics of Plasmas, Vol. 2, November 1995, pp. 3933-4024. As is well known, in the United States of America research on the target physics basis for indirect drive remained largely classified until 1994. The indirect drive approaches were closely related to nuclear weapons research at Lawrence Livermore and Los Alamos National Laboratories. In Japan and other countries, inertial confinement fusion research for civil energy has been successfully performed to achieve DT fuel pellet compression up to 1000 times normal density, and indirect drive concepts, such as the `Cannon Ball' scheme, also prevailed at several international conferences. In these circumstances the international fusion community proposed the Madrid Manifesto in 1988, which urged openness of ICF information to promote international collaboration on civil energy research for the future resources of the human race. This proposal was also supported by some of the US scientists. The United States Department of Energy revised its classification guidelines for ICF six years after the Madrid Manifesto. This first book from the USA treating target physics issues, covering topics from implosion dynamics to hydrodynamic stability, ignition physics, high-gain target design and the scope for energy applications is

  7. Development and characterization of a Z-pinch-driven hohlraum high-yield inertial confinement fusion target concept

    NASA Astrophysics Data System (ADS)

    Cuneo, Michael E.; Vesey, Roger A.; Porter, John L.; Chandler, Gordon A.; Fehl, David L.; Gilliland, Terrance L.; Hanson, David L.; McGurn, John S.; Reynolds, Paul G.; Ruggles, Laurence E.; Seamen, Hans; Spielman, Rick B.; Struve, Ken W.; Stygar, William A.; Simpson, Walter W.; Torres, Jose A.; Wenger, David F.; Hammer, James H.; Rambo, Peter W.; Peterson, Darrell L.; Idzorek, George C.

    2001-05-01

    Initial experiments to study the Z-pinch-driven hohlraum high-yield inertial confinement fusion (ICF) concept of Hammer, Tabak, and Porter [Hammer et al., Phys. Plasmas 6, 2129 (1999)] are described. The relationship between measured pinch power, hohlraum temperature, and secondary hohlraum coupling ("hohlraum energetics") is well understood from zero-dimensional semianalytic, and two-dimensional view factor and radiation magnetohydrodynamics models. These experiments have shown the highest x-ray powers coupled to any Z-pinch-driven secondary hohlraum (26±5 TW), indicating the concept could scale to fusion yields of >200 MJ. A novel, single-sided power feed, double-pinch driven secondary that meets the pinch simultaneity requirements for polar radiation symmetry has also been developed. This source will permit investigation of the pinch power balance and hohlraum geometry requirements for ICF relevant secondary radiation symmetry, leading to a capsule implosion capability on the Z accelerator [Spielman et al., Phys. Plasmas 5, 2105 (1998)].

  8. Spallation as a dominant source of pusher-fuel and hot-spot mix in inertial confinement fusion capsules

    NASA Astrophysics Data System (ADS)

    Orth, Charles D.

    2016-02-01

    We suggest that a potentially dominant but previously neglected source of pusher-fuel and hot-spot "mix" may have been the main degradation mechanism for fusion energy yields of modern inertial confinement fusion (ICF) capsules designed and fielded to achieve high yields—not hydrodynamic instabilities. This potentially dominant mix source is the spallation of small chunks or "grains" of pusher material into the fuel regions whenever (1) the solid material adjacent to the fuel changes its phase by nucleation and (2) this solid material spalls under shock loading and sudden decompression. We describe this mix mechanism, support it with simulations and experimental evidence, and explain how to eliminate it and thereby allow higher yields for ICF capsules and possibly ignition at the National Ignition Facility.

  9. Spallation as a dominant source of pusher-fuel and hot-spot mix in inertial confinement fusion capsules

    DOE PAGESBeta

    Orth, Charles D.

    2016-02-23

    We suggest that a potentially dominant but previously neglected source of pusher-fuel and hot-spot “mix” may have been the main degradation mechanism for fusion energy yields of modern inertial confinement fusion (ICF) capsules designed and fielded to achieve high yields — not hydrodynamic instabilities. This potentially dominant mix source is the spallation of small chunks or “grains” of pusher material into the fuel regions whenever (1) the solid material adjacent to the fuel changes its phase by nucleation, and (2) this solid material spalls under shock loading and sudden decompression. Finally, we describe this mix mechanism, support it with simulationsmore » and experimental evidence, and explain how to eliminate it and thereby allow higher yields for ICF capsules and possibly ignition at the National Ignition Facility.« less

  10. Single Crystal Growth and Formation of Defects in Deuterium-Tritium Ice Layers for Inertial Confinement Fusion

    SciTech Connect

    Chernov, A A; Kozioziemski, B J; Koch, J A; Atherton, L J; Johnson, M A; Hamza, A V; Kucheyev, S O; Lugten, J B; Mapoles, E A; Moody, J D; Salmonson, J D; Sater, J D

    2008-09-05

    We identify vapor-etched grain boundary grooves on the solid-vapor interface as the main source of surface roughness in the Deuterium-Tritium (D-T) fuel layers which are solidified and then cooled. Current inertial confinement fusion target designs impose stringent limits to the cross sectional area and total volume of these grooves. Formation of these grain boundaries occurs over timescales of hours as the dislocation network anneals, and is inevitable in a plastically deformed material. Therefore, either cooling on a much shorter time scale or a technique that requires no cooling after solidification should be used to minimize the fuel layer surface roughness.

  11. Fabrication of cryogenic inertial-confinement-fusion targets using target free-fall technique. Report No. 2-82

    SciTech Connect

    Kim, K.; Murphy, M.J.

    1982-04-01

    Techniques for fabricating cryogenic inertial confinement fusion targets (i.e., spherical shells containing a uniform layer of DT ice) are investigated using target free-fall concept. Detection and characterization of the moving targets are effected by optoelectronic means, of which the principal is an RF ac-interferometer. This interferometer system demonstrates, for the first time, the speed capabilities of the phase-modulation ac-interferometry. New techiques developed for handling, holding, launching, and transporting targets are also described. Results obtained at both room and cryogenic temperatures are presented.

  12. Direct asymmetry measurement of temperature and density spatial distributions in inertial confinement fusion plasmas from pinhole space-resolved spectra

    SciTech Connect

    Nagayama, T.; Mancini, R. C.; Florido, R.; Mayes, D.; Tommasini, R.; Koch, J. A.; Delettrez, J. A.; Regan, S. P.; Smalyuk, V. A.

    2014-05-15

    Two-dimensional space-resolved temperature and density images of an inertial confinement fusion (ICF) implosion core have been diagnosed for the first time. Argon-doped, direct-drive ICF experiments were performed at the Omega Laser Facility and a collection of two-dimensional space-resolved spectra were obtained from an array of gated, spectrally resolved pinhole images recorded by a multi-monochromatic x-ray imager. Detailed spectral analysis revealed asymmetries of the core not just in shape and size but in the temperature and density spatial distributions, thus characterizing the core with an unprecedented level of detail.

  13. Spatial profiling using a Time of Flight Diagnostic and applications of deuterim-deuterium fusion in Inertial Electrostatic Confinement fusion devices

    NASA Astrophysics Data System (ADS)

    Donovan, David C.

    2011-12-01

    The Inertial Electrostatic Confinement (IEC) Fusion Research Group at the University of Wisconsin-Madison utilizes IEC devices as small-scale neutron generators using D-D fusion to create 2.45 MeV neutrons for the purpose of detecting clandestine material. Detection of explosives in particular can be accomplished using thermal neutron capture methods to identify characteristic nitrogen signatures in explosive material. Research has been conducted to increase reliability of detection, decrease interrogation time, and increase the steady-state operational time. Efforts have also been made to increase the neutron production rate of the device. Optimization studies have varied the configuration and design of the electrodes and have resulted in system configurations with up to 50 percent higher neutron production rates than have previously been utilized. A new feedthrough design has been constructed that is intended to increase the maximum operating voltage from 175 kV with the previous feedthrough to 300 kV. Neutron production rates scale almost linearly with both current and voltage, so the IEC device will be capable of operation at higher neutron producing regimes than have ever before been achieved. The optimization efforts involve the use of several new diagnostic tools developed at UW, which are the Fusion Ion Doppler (FIDO) Diagnostic and the Time of Flight (TOF) Diagnostic. FIDO provides the energy spectra of the charged fusion products and reactants created in the IEC device. The FIDO Diagnostic was originally only capable of studying D-D fusion, but with recent advancements is now able to study both D-D and D-3He fusion. The TOF Diagnostic provides spatial information along with the energy resolution of where the fusion reactions are occurring in the IEC device. Development of the diagnostics has involved the implementation of timing electronics, alignment systems, data acquisition software, computational post-processing, and upgrades to the experimental

  14. Ion kinetic effects on the ignition and burn of inertial confinement fusion targets: A multi-scale approach

    SciTech Connect

    Peigney, B. E.; Larroche, O.

    2014-12-15

    In this article, we study the hydrodynamics and burn of the thermonuclear fuel in inertial confinement fusion pellets at the ion kinetic level. The analysis is based on a two-velocity-scale Vlasov-Fokker-Planck kinetic model that is specially tailored to treat fusion products (suprathermal α-particles) in a self-consistent manner with the thermal bulk. The model assumes spherical symmetry in configuration space and axial symmetry in velocity space around the mean flow velocity. A typical hot-spot ignition design is considered. Compared with fluid simulations where a multi-group diffusion scheme is applied to model α transport, the full ion-kinetic approach reveals significant non-local effects on the transport of energetic α-particles. This has a direct impact on hydrodynamic spatial profiles during combustion: the hot spot reactivity is reduced, while the inner dense fuel layers are pre-heated by the escaping α-suprathermal particles, which are transported farther out of the hot spot. We show how the kinetic transport enhancement of fusion products leads to a significant reduction of the fusion yield.

  15. High power millimeter wave ECRH source needs for fusion program

    SciTech Connect

    Not Available

    1984-06-01

    This document stems from the four-day Gyrotron Symposium held at the US Department of Energy (DOE) Headquarters on June 13-16, 1983, and serves as a position paper for the Office of Fusion Energy, DOE, on high-power millimeter wave source development for Electron Cyclotron Heating (ECH) of plasmas. It describes the fusion program needs for gyrotron as ECH sources, their current status, and desirable development strategies.

  16. Inertial confinement fusion with direct electric generation by magnetic flux comparession

    SciTech Connect

    Lasche, G.P.

    1983-01-01

    A high-power-density laser-fusion-reactor concept in investigated in which directed kinetic enery imparted to a large mass of liquid lithium--in which the fusion target is centrally located--is maximized. In turn, this kinetic energy is converted directly to electricity with, potentially, very high efficiency by work done against a pulsed magnetic field applied exterior to the lithium. Because the concept maximizes the blanket thickness per unit volume of lithium, neutron-induced radioactivities in the reaction chamber wall can be many orders of magnitude less than is typical of D-T fusion reactor concepts.

  17. Self-consistent stability analysis of ablation fronts in inertial confinement fusion

    NASA Astrophysics Data System (ADS)

    Goncharov, Valeri N.

    1998-09-01

    In Inertial Confinement Fusion (ICF) implosions, a cold target material is accelerated by a hot, low density plasma. The surface between the heavy and light materials is Rayleigh-Taylor (RT) unstable similar to the interface between two fluids of constant densities ρh and ρl subject to a gravitational field g pointing toward the lighter fluid ρl. The classical treatment of the sharp-interface RT instability leads to a linear growth rate γcl=/sqrt[ATkg], where k is the perturbation wave number, g is the acceleration, and AT=(ρh- ρl)/(ρh+ρl) is the Atwood number. In this thesis, the linear stability analysis of accelerated ICF targets is carried out including the effects of ablative flow and finite thermal conduction. The thermal conductivity κ has a power law dependence on the temperature, κ~Tν, with a power index /nu. It is shown that the physical mechanisms inherent to the ablative compression (finite density-gradient scale-length, mass flow across the ablation region, transverse and lateral thermal conductivity, etc.) reduce the classical growth rate of the unstable modes γ<γcl. The most important parameter characterizing the instability is the Froude number Fr defined as Fr=Va2/(gL0), where Va is the ablation velocity, g is the target acceleration, and L0 is the characteristic width of the ablation region. For ablation-fronts with large Froude numbers, the unstable spectrum consists only of long-wavelength modes (kLmin/ll1, where Lmin is the minimum density-gradient scale-length) and short-wavelengths (kLmin/gg1) are stable (the cutoff wavelength is much longer than the minimum density-gradient scale-length). The main physical mechanisms stabilizing the Rayleigh-Taylor growth of the interface in this case are the jump of the dynamic pressure pd=/rho V2 caused by lateral thermal conduction, and the mass flow through the ablation region. For the ablation fronts with small Froude numbers, the unstable spectrum consists of long as well as short

  18. Self-organized criticality and the dynamics of near-marginal turbulent transport in magnetically confined fusion plasmas

    NASA Astrophysics Data System (ADS)

    Sanchez, R.; Newman, D. E.

    2015-12-01

    The high plasma temperatures expected at reactor conditions in magnetic confinement fusion toroidal devices suggest that near-marginal operation could be a reality in future devices and reactors. By near-marginal it is meant that the plasma profiles might wander around the local critical thresholds for the onset of instabilities. Self-organized criticality (SOC) was suggested in the mid 1990s as a more proper paradigm to describe the dynamics of tokamak plasma transport in near-marginal conditions. It advocated that, near marginality, the evolution of mean profiles and fluctuations should be considered simultaneously, in contrast to the more common view of a large separation of scales existing between them. Otherwise, intrinsic features of near-marginal transport would be missed, that are of importance to understand the properties of energy confinement. In the intervening 20 years, the relevance of the idea of SOC for near-marginal transport in fusion plasmas has transitioned from an initial excessive hype to the much more realistic standing of today, which we will attempt to examine critically in this review paper. First, the main theoretical ideas behind SOC will be described. Secondly, how they might relate to the dynamics of near-marginal transport in real magnetically confined plasmas will be discussed. Next, we will review what has been learnt about SOC from various numerical studies and what it has meant for the way in which we do numerical simulation of fusion plasmas today. Then, we will discuss the experimental evidence available from the several experiments that have looked for SOC dynamics in fusion plasmas. Finally, we will conclude by identifying the various problems that still remain open to investigation in this area. Special attention will be given to the discussion of frequent misconceptions and ongoing controversies. The review also contains a description of ongoing efforts that seek effective transport models better suited than traditional

  19. Overview of the US Magnetic Fusion Energy Program

    SciTech Connect

    Wiffen, F.W. ); Dowling, R.J.; Marton, W.A.; Eckstrand, S.A. . Office of Fusion Energy)

    1990-01-01

    Since the 1988 Symposium on Fusion Technology, steady progress has been made in the US Magnetic Fusion Energy Program. The large US tokamaks have reached new levels of plasma performance with associated improvements in the understanding of transport. The technology support for ongoing and future devices is similarly advancing with notable advances in magnetic, rf heating tubes, pellet injector, plasma interactive materials, tritium handling, structural materials, and system studies. Currently, a high level DOE review of the program is underway to provide recommendations for a strategic plan.

  20. Fusion Safety Program Annual Report, Fiscal Year 1996

    SciTech Connect

    Longhurst, G.R.; Anderl, R.A.; Cadwallader, L.C.

    1996-12-01

    This report summarizes the major activities of the Fusion Safety Program in FY 1996. The Idaho National Engineering Laboratory (INEL) is the designated lead laboratory, and Lockheed Martin Idaho Technologies Company is the prime contractor for this program. The Fusion Safety Program was initiated in 1979. The objective is to perform research and develop data needed to ensure safety in fusion facilities. Activities include experiments, analysis, code development and application, and other forms of research. These activities are conducted at the INEL, at other DOE laboratories, and at other institutions. Among the technical areas covered in this report are tritium safety, chemical reactions and activation product release, risk assessment failure rate database development, and safety code development and application to fusion safety issues. Most of this work has been done in support of the International Thermonuclear Experimental Reactor (ITER). Work done for ITER this year has focused on developing the needed information for the Non- Site- Specific Safety Report (NSSR-1). A final area of activity described is development of the new DOE Technical Standards for Safety of Magnetic Fusion Facilities.

  1. Assessment of liquid hydrogen cooled MgB2 conductors for magnetically confined fusion

    NASA Astrophysics Data System (ADS)

    Glowacki, B. A.; Nuttall, W. J.

    2008-02-01

    Importantly environmental factors are not the only policy-driver for the hydrogen economy. Over the timescale of the development of fusion energy systems, energy security issues are likely to motivate a shift towards both hydrogen production and fusion as an energy source. These technologies combine local control of the system with the collaborative research interests of the major energy users in the global economy. A concept Fusion Island Reactor that might be used to generate H2 (rather than electricity) is presented. Exploitation of produced hydrogen as a coolant and as a fuel is proposed in conjunction with MgB2 conductors for the tokomak magnets windings, and electrotechnical devices for Fusion Island's infrastructure. The benefits of using MgB2 over the Nb-based conductors during construction, operation and decommissioning of the Fusion Island Reactor are presented. The comparison of Nb3Sn strands for ITER fusion magnet with newly developed high field composite MgB2 PIT conductors has shown that at 14 Tesla MgB2 possesses better properties than any of the Nb3Sn conductors produced. In this paper the potential of MgB2 conductors is examined for tokamaks of both the conventional ITER type and a Spherical Tokamak geometry. In each case MgB2 is considered as a conductor for a range of field coil applications and the potential for operation at both liquid helium and liquid hydrogen temperatures is considered. Further research plans concerning the application of MgB2 conductors for Fusion Island are also considered.

  2. THE GENERAL ATOMICS FUSION THEORY PROGRAM ANNUAL REPORT FOR GRANT YEAR 2004

    SciTech Connect

    PROJECT STAFF

    2004-12-01

    The dual objective of the fusion theory program at General Atomics (GA) is to significantly advance our scientific understanding of the physics of fusion plasmas and to support the DIII-D and other tokamak experiments. The program plan is aimed at contributing significantly to the Fusion Energy Science and the Tokamak Concept Improvement goals of the Office of Fusion Energy Sciences (OFES).

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

    SciTech Connect

    Armijo, Julien

    2006-10-01

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

  4. A Microcomputer Program for Evaluating Pumping Test Results for Confined Aquifers.

    ERIC Educational Resources Information Center

    Smith, Stephen M.

    1986-01-01

    Describes an interactive, self-prompting BASIC program that can be incorporated in introductory and intermediate hydrology courses. Exlains how the program can be used to evaluate pumping test data and also to calculate transmissivity and storativity values of confined aquifers. The program is written for the IBM PC. (ML)

  5. Status of target physics for inertial confinement fusion: Report on the review at DOE Headquarters, Germantown, MD on November 14--17, 1988

    SciTech Connect

    Not Available

    1990-03-09

    A four day review to assess the status of target physics of inertial confinement fusion was held at US Department of Energy (DOE) Headquarters on November 14--17, 1988. This review completes the current series of reviews of the inertial fusion program elements to assess the status of the data base for a decision to proceed with the proposed Laboratory Microfusion Facility (LMF) that is being planned. In addition to target physics, the program elements that have been reviewed previously include the driver technology development for KrF and solid-state lasers, and the light-on beam pulsed power system. This series of reviews was undertaken for internal DOE assessment in anticipation of the ICF program review mandated by the Congress in 1988 to be completed in 1990 to assess the significance and implications of the progress that has been realized in the laboratory and the underground Halite/Centurion experiments. For this target physics review, both the direct and the indirect drive approaches were considered. The principal issues addressed in this review were: Is the present target physics data base adequate for a decision to proceed with design and construction of LMF now as opposed to continue planning activities at this time What specific additional target physics data are desirable to reduce the risk for a DOE decision to construct an LMF What is the role for continuation of Halite/Centurion experiments What priority should be given to the direct drive approach Are the program elements optimally structured to resolve the critical issues for an LMF decision Specific findings relating to these five issues are summarized in the following.

  6. Determination of Atomic Data Pertinent to the Fusion Energy Program

    SciTech Connect

    Reader, J.

    2013-06-11

    We summarize progress that has been made on the determination of atomic data pertinent to the fusion energy program. Work is reported on the identification of spectral lines of impurity ions, spectroscopic data assessment and compilations, expansion and upgrade of the NIST atomic databases, collision and spectroscopy experiments with highly charged ions on EBIT, and atomic structure calculations and modeling of plasma spectra.

  7. Fusion Safety Program annual report, Fiscal Year 1993

    SciTech Connect

    Longhurst, G.R.; Cadwallader, L.C.; Dolan, T.J.; Herring, J.S.; McCarthy, K.A.; Merrill, B.J.; Motloch, C.G.; Petti, D.A.

    1993-12-01

    This report summarizes the major activities of the Fusion Safety Program in Fiscal Year 1993. The Idaho National Engineering Laboratory (INEL) has been designated by DOE as the lead laboratory for fusion safety, and EG&G Idaho, Inc., is the prime contractor for INEL operations. The Fusion Safety Program was initiated in 1979. Activities are conducted at the INEL and in participating organizations, including universities and private companies. Technical areas covered in the report include tritium safety, beryllium safety, activation product release, reactions involving potential plasma-facing materials, safety of fusion magnet systems, plasma disruptions and edge physics modeling, risk assessment failure rates, computer codes for reactor transient analysis, and regulatory support. These areas include work completed in support of the International Thermonuclear Experimental Reactor (ITER). Also included in the report are summaries of the safety and environmental studies performed at the INEL for the Tokamak Physics Experiment and the Tokamak Fusion Test Reactor projects at the Princeton Plasma Physics Laboratory and a summary of the technical support for the ARIES/PULSAR commercial reactor design studies.

  8. Magnetic Fusion Energy Plasma Interactive and High Heat Flux Components: Volume 5, Technical assessment of critical issues in the steady state operation of fusion confinement devices

    SciTech Connect

    Not Available

    1988-01-01

    Critical issues for the steady state operation of plasma confinement devices exist in both the physics and technology fields of fusion research. Due to the wide range and number of these issues, this technical assessment has focused on the crucial issues associated with the plasma physics and the plasma interactive components. The document provides information on the problem areas that affect the design and operation of a steady state ETR or ITER type confinement device. It discusses both tokamaks and alternative concepts, and provides a survey of existing and planned confinement machines and laboratory facilities that can address the identified issues. A universal definition of steady state operation is difficult to obtain. From a physics point of view, steady state is generally achieved when the time derivatives approach zero and the operation time greatly exceeds the characteristic time constants of the device. Steady state operation for materials depends on whether thermal stress, creep, fatigue, radiation damage, or power removal are being discussed. For erosion issues, the fluence and availability of the machine for continuous operation are important, assuming that transient events such as disruptions do not limit the component lifetimes. The panel suggests, in general terms, that steady state requires plasma operation from 100 to 1000 seconds and an availability of more than a few percent, which is similar to the expectations for an ETR type device. The assessment of critical issues for steady state operation is divided into four sections: physics issues; technology issues; issues in alternative concepts; and devices and laboratory facilities that can address these problems.

  9. Block Ignition Inertial Confinement Fusion (ICF) with Condensed Matter Cluster Type Targets for p-B11 Powered Space Propulsion

    NASA Astrophysics Data System (ADS)

    Miley, George H.; Hora, H.; Badziak, J.; Wolowski, J.; Sheng, Zheng-Ming; Zhang, Jie; Osman, F.; Zhang, Weiyan; tu He, Xia

    2009-03-01

    The use of laser-driven Inertial Confinement Fusion (ICF) for space propulsion has been the subject of several earlier conceptual design studies, (see: Orth, 1998; and other references therein). However, these studies were based on older ICF technology using either "direct "or "in-direct x-ray driven" type target irradiation. Important new directions have opened for laser ICF in recent years following the development of "chirped" lasers capable of ultra short pulses with powers of TW up to few PW which leads to the concept of "fast ignition (FI)" to achieve higher energy gains from target implosions. In a recent publication the authors showed that use of a modified type of FI, termed "block ignition" (Miley et al., 2008), could meet many of the requirements anticipated (but not then available) by the designs of the Vehicle for Interplanetary Space Transport Applications (VISTA) ICF fusion propulsion ship (Orth, 2008) for deep space missions. Subsequently the first author devised and presented concepts for imbedding high density condensed matter "clusters" of deuterium into the target to obtain ultra high local fusion reaction rates (Miley, 2008). Such rates are possible due to the high density of the clusters (over an order of magnitude above cryogenic deuterium). Once compressed by the implosion, the yet higher density gives an ultra high reaction rate over the cluster volume since the fusion rate is proportional to the square of the fuel density. Most recently, a new discovery discussed here indicates that the target matrix could be composed of B11 with proton clusters imbedded. This then makes p-B11 fusion practical, assuming all of the physics issues such as stability of the clusters during compression are resolved. Indeed, p-B11 power is ideal for fusion propulsion since it has a minimum of unwanted side products while giving most of the reaction energy to energetic alpha particles which can be directed into an exhaust (propulsion) nozzle. Power plants using p

  10. Block Ignition Inertial Confinement Fusion (ICF) with Condensed Matter Cluster Type Targets for p-B11 Powered Space Propulsion

    SciTech Connect

    Miley, George H.; Hora, H.; Badziak, J.; Wolowski, J.; Sheng Zhengming; Zhang Jie; Osman, F.; Zhang Weiyan; Tuhe Xia

    2009-03-16

    The use of laser-driven Inertial Confinement Fusion (ICF) for space propulsion has been the subject of several earlier conceptual design studies, (see: Orth, 1998; and other references therein). However, these studies were based on older ICF technology using either 'direct' or 'in-direct x-ray driven' type target irradiation. Important new directions have opened for laser ICF in recent years following the development of 'chirped' lasers capable of ultra short pulses with powers of TW up to few PW which leads to the concept of 'fast ignition (FI)' to achieve higher energy gains from target implosions. In a recent publication the authors showed that use of a modified type of FI, termed 'block ignition' (Miley et al., 2008), could meet many of the requirements anticipated (but not then available) by the designs of the Vehicle for Interplanetary Space Transport Applications (VISTA) ICF fusion propulsion ship (Orth, 2008) for deep space missions. Subsequently the first author devised and presented concepts for imbedding high density condensed matter 'clusters' of deuterium into the target to obtain ultra high local fusion reaction rates (Miley, 2008). Such rates are possible due to the high density of the clusters (over an order of magnitude above cryogenic deuterium). Once compressed by the implosion, the yet higher density gives an ultra high reaction rate over the cluster volume since the fusion rate is proportional to the square of the fuel density. Most recently, a new discovery discussed here indicates that the target matrix could be composed of B{sup 11} with proton clusters imbedded. This then makes p-B{sup 11} fusion practical, assuming all of the physics issues such as stability of the clusters during compression are resolved. Indeed, p-B{sup 11} power is ideal for fusion propulsion since it has a minimum of unwanted side products while giving most of the reaction energy to energetic alpha particles which can be directed into an exhaust (propulsion) nozzle

  11. Fusion Safety Program annual report, fiscal year 1992

    SciTech Connect

    Holland, D.F.; Cadwallader, L.C.; Herring, J.S.; Longhurst, G.R.; McCarthy, K.A.; Merrill, B.J.; Piet, S.J.

    1993-01-01

    This report summarizes the major activities of the Fusion Safety Program in fiscal year 1992. The Idaho National Engineering Laboratory (INEL) is the designated lead laboratory and EG&G Idaho, Inc. is the prime contractor for this program. The Fusion Safety Program was initiated in 1979. Activities are conducted at the INEL and in participating organizations including the Westinghouse Hanford Company at the Hanford Engineering Development Laboratory, the Massachusetts Institute of Technology, and the University of Wisconsin. The technical areas covered in the report include tritium safety, activation product release, reactions involving beryllium, reactions involving lithium breeding materials, safety of fusion magnet systems, plasma disruptions, risk assessment failure rate data base, and computer code development for reactor transients. Also included in the report is a summary of the safety and environmental studies performed by the INEL for the Tokamak Physics Experiments and the Tokamak Fusion Test Reactor, the safety analysis for the International Thermonuclear Experimental Reactor design, and the technical support for the ARIES commercial reactor design study.

  12. Fusion Safety Program annual report, fiscal year 1992

    SciTech Connect

    Holland, D.F.; Cadwallader, L.C.; Herring, J.S.; Longhurst, G.R.; McCarthy, K.A.; Merrill, B.J.; Piet, S.J.

    1993-01-01

    This report summarizes the major activities of the Fusion Safety Program in fiscal year 1992. The Idaho National Engineering Laboratory (INEL) is the designated lead laboratory and EG G Idaho, Inc. is the prime contractor for this program. The Fusion Safety Program was initiated in 1979. Activities are conducted at the INEL and in participating organizations including the Westinghouse Hanford Company at the Hanford Engineering Development Laboratory, the Massachusetts Institute of Technology, and the University of Wisconsin. The technical areas covered in the report include tritium safety, activation product release, reactions involving beryllium, reactions involving lithium breeding materials, safety of fusion magnet systems, plasma disruptions, risk assessment failure rate data base, and computer code development for reactor transients. Also included in the report is a summary of the safety and environmental studies performed by the INEL for the Tokamak Physics Experiments and the Tokamak Fusion Test Reactor, the safety analysis for the International Thermonuclear Experimental Reactor design, and the technical support for the ARIES commercial reactor design study.

  13. Refraction-Enhanced X-ray Radiography for Inertial Confinement Fusion and Laser-Produced Plasma Applications

    SciTech Connect

    Koch, J A; Landen, O L; Kozioziemski, B J; Izumi, N; Dewald, E L; Salmonson, J D; Hammel, B A

    2008-08-26

    We explore various laser-produced plasma and inertial-confinement fusion (ICF) applications of phase-contrast x-ray radiography, and we show how the main features of these enhancements can be considered from a geometrical optics perspective as refraction enhancements. This perspective simplifies the analysis, and often permits simple analytical formulae to be derived that predict the enhancements. We explore a raytrace approach to various material interface applications, and we explore a more general example of refractive bending of x-rays by an implosion plasma. We find that refraction-enhanced x-ray radiography of implosions may provide a means to quantify density differences across shock fronts as well as density variations caused by local heating due to high-Z dopants. We also point out that refractive bending by implosions plasmas can blur fine radiograph features, and can also provide misleading contrast information in area-backlit pinhole imaging experiments unless its effects are taken into consideration.

  14. Multi-stage FEL amplifier with diaphragm focusing line as direct energy driver for inertial confinement fusion

    SciTech Connect

    Saldin, E.L.; Schneidmiller, E.A.; Ulyanov, Yu.N.

    1995-12-31

    An FEL based energy driver for Inertial Confinement Fusion (ICF) is proposed. The key element of the scheme is free electron laser system. Novel technical solutions, namely, using of multichannel, multi-stage FEL amplifier with diaphragm focusing line, reveal a possibility to construct the FEL system operating at radiation wavelength {lambda} = 0.5 {mu}m and providing flush energy E = 1 MJ and brightness 4 x 10{sup 22} W cm{sup -2} sr{sup -1} within steering pulse duration {tau} {approximately} 0.1-2 ns. Total energy efficiency of the proposed ICF energy driver is about of 11% and repetition rate is 40 Hz. It is shown that the FEL based ICF energy driver may be constructed at the present level of accelerator technique R& D.

  15. Generating energetic electrons through staged acceleration in the two-plasmon-decay instability in inertial confinement fusion.

    PubMed

    Yan, R; Ren, C; Li, J; Maximov, A V; Mori, W B; Sheng, Z-M; Tsung, F S

    2012-04-27

    A new hot-electron generation mechanism in two-plasmon-decay instabilities is described based on a series of 2D, long-term (~10 ps) particle-in-cell and fluid simulations under parameters relevant to inertial confinement fusion. The simulations show that significant laser absorption and hot-electron generation occur in the nonlinear stage. The hot electrons are stage accelerated from the low-density region to the high-density region. New modes with small phase velocities develop in the low-density region in the nonlinear stage and form the first stage for electron acceleration. Electron-ion collisions are shown to significantly reduce the efficiency of this acceleration mechanism. PMID:22680873

  16. Uniformity of spherical shock wave dynamically stabilized by two successive laser profiles in direct-drive inertial confinement fusion implosions

    NASA Astrophysics Data System (ADS)

    Temporal, M.; Canaud, B.; Garbett, W. J.; Ramis, R.

    2015-10-01

    The implosion uniformity of a directly driven spherical inertial confinement fusion capsule is considered within the context of the Laser Mégajoule configuration. Two-dimensional (2D) hydrodynamic simulations have been performed assuming irradiation with two laser beam cones located at 49° and 131° with respect to the axis of symmetry. The laser energy deposition causes an inward shock wave whose surface is tracked in time, providing the time evolution of its non-uniformity. The illumination model has been used to optimize the laser intensity profiles used as input in the 2D hydro-calculations. It is found that a single stationary laser profile does not maintain a uniform shock front over time. To overcome this drawback, it is proposed to use two laser profiles acting successively in time, in order to dynamically stabilize the non-uniformity of the shock front.

  17. First Measurements of Fuel-Ablator Interface Instability Growth in Inertial Confinement Fusion Implosions on the National Ignition Facility.

    PubMed

    Weber, C R; Döppner, T; Casey, D T; Bunn, T L; Carlson, L C; Dylla-Spears, R J; Kozioziemski, B J; MacPhee, A G; Nikroo, A; Robey, H F; Sater, J D; Smalyuk, V A

    2016-08-12

    Direct measurements of hydrodynamic instability growth at the fuel-ablator interface in inertial confinement fusion (ICF) implosions are reported for the first time. These experiments investigate one of the degradation mechanisms behind the lower-than-expected performance of early ICF implosions on the National Ignition Facility. Face-on x-ray radiography is used to measure instability growth occurring between the deuterium-tritium fuel and the plastic ablator from well-characterized perturbations. This growth starts in two ways through separate experiments-either from a preimposed interface modulation or from ablation front feedthrough. These experiments are consistent with analytic modeling and radiation-hydrodynamic simulations, which say that a moderately unstable Atwood number and convergence effects are causing in-flight perturbation growth at the interface. The analysis suggests that feedthrough from outersurface perturbations dominates the interface perturbation growth at mode 60. PMID:27563971

  18. Two-plasmon decay mitigation in direct-drive inertial-confinement-fusion experiments using multilayer targets

    DOE PAGESBeta

    Follett, R. K.; Delettrez, J. A.; Edgell, D. H.; Goncharov, V. N.; Henchen, R. J.; Katz, J.; Michel, D. T.; Myatt, J. F.; Shaw, J.; Solodov, A. A.; et al

    2016-04-15

    Multilayer direct-drive inertial-confinement-fusion (ICF) targets are shown to significantly reduce two-plasmon-decay (TPD) driven hot-electron production while maintaining high hydrodynamic efficiency. Implosion experiments on the OMEGA Laser used targets with silicon layered between an inner beryllium and outer silicon-doped plastic ablator. A factor of five reduction in hot-electron generation (> 50 keV) was observed in the multilayer targets relative to pure CH targets. Three-dimensional simulations of the TPD driven hot-electron production using a laser-plasma interaction code (LPSE) that includes nonlinear and kinetic effects show excellent agreement with the measurements. As a result, the simulations suggest that the reduction in hot-electron productionmore » observed in the multilayer targets is primarily due to increased electron-ion collisional damping.« less

  19. First Measurements of Fuel-Ablator Interface Instability Growth in Inertial Confinement Fusion Implosions on the National Ignition Facility

    NASA Astrophysics Data System (ADS)

    Weber, C. R.; Döppner, T.; Casey, D. T.; Bunn, T. L.; Carlson, L. C.; Dylla-Spears, R. J.; Kozioziemski, B. J.; MacPhee, A. G.; Nikroo, A.; Robey, H. F.; Sater, J. D.; Smalyuk, V. A.

    2016-08-01

    Direct measurements of hydrodynamic instability growth at the fuel-ablator interface in inertial confinement fusion (ICF) implosions are reported for the first time. These experiments investigate one of the degradation mechanisms behind the lower-than-expected performance of early ICF implosions on the National Ignition Facility. Face-on x-ray radiography is used to measure instability growth occurring between the deuterium-tritium fuel and the plastic ablator from well-characterized perturbations. This growth starts in two ways through separate experiments—either from a preimposed interface modulation or from ablation front feedthrough. These experiments are consistent with analytic modeling and radiation-hydrodynamic simulations, which say that a moderately unstable Atwood number and convergence effects are causing in-flight perturbation growth at the interface. The analysis suggests that feedthrough from outersurface perturbations dominates the interface perturbation growth at mode 60.

  20. Two-Plasmon Decay Mitigation in Direct-Drive Inertial-Confinement-Fusion Experiments Using Multilayer Targets.

    PubMed

    Follett, R K; Delettrez, J A; Edgell, D H; Goncharov, V N; Henchen, R J; Katz, J; Michel, D T; Myatt, J F; Shaw, J; Solodov, A A; Stoeckl, C; Yaakobi, B; Froula, D H

    2016-04-15

    Multilayer direct-drive inertial-confinement-fusion targets are shown to significantly reduce two-plasmon decay (TPD) driven hot-electron production while maintaining high hydrodynamic efficiency. Implosion experiments on the OMEGA laser used targets with silicon layered between an inner beryllium and outer silicon-doped plastic ablator. A factor-of-5 reduction in hot-electron generation (>50  keV) was observed in the multilayer targets relative to pure CH targets. Three-dimensional simulations of the TPD-driven hot-electron production using a laser-plasma interaction code (lpse) that includes nonlinear and kinetic effects show good agreement with the measurements. The simulations suggest that the reduction in hot-electron production observed in the multilayer targets is primarily caused by increased electron-ion collisional damping. PMID:27127973

  1. Two-Plasmon Decay Mitigation in Direct-Drive Inertial-Confinement-Fusion Experiments Using Multilayer Targets

    NASA Astrophysics Data System (ADS)

    Follett, R. K.; Delettrez, J. A.; Edgell, D. H.; Goncharov, V. N.; Henchen, R. J.; Katz, J.; Michel, D. T.; Myatt, J. F.; Shaw, J.; Solodov, A. A.; Stoeckl, C.; Yaakobi, B.; Froula, D. H.

    2016-04-01

    Multilayer direct-drive inertial-confinement-fusion targets are shown to significantly reduce two-plasmon decay (TPD) driven hot-electron production while maintaining high hydrodynamic efficiency. Implosion experiments on the OMEGA laser used targets with silicon layered between an inner beryllium and outer silicon-doped plastic ablator. A factor-of-5 reduction in hot-electron generation (>50 keV ) was observed in the multilayer targets relative to pure CH targets. Three-dimensional simulations of the TPD-driven hot-electron production using a laser-plasma interaction code (lpse) that includes nonlinear and kinetic effects show good agreement with the measurements. The simulations suggest that the reduction in hot-electron production observed in the multilayer targets is primarily caused by increased electron-ion collisional damping.

  2. Uniformity of spherical shock wave dynamically stabilized by two successive laser profiles in direct-drive inertial confinement fusion implosions

    SciTech Connect

    Temporal, M.; Canaud, B.; Garbett, W. J.; Ramis, R.

    2015-10-15

    The implosion uniformity of a directly driven spherical inertial confinement fusion capsule is considered within the context of the Laser Mégajoule configuration. Two-dimensional (2D) hydrodynamic simulations have been performed assuming irradiation with two laser beam cones located at 49° and 131° with respect to the axis of symmetry. The laser energy deposition causes an inward shock wave whose surface is tracked in time, providing the time evolution of its non-uniformity. The illumination model has been used to optimize the laser intensity profiles used as input in the 2D hydro-calculations. It is found that a single stationary laser profile does not maintain a uniform shock front over time. To overcome this drawback, it is proposed to use two laser profiles acting successively in time, in order to dynamically stabilize the non-uniformity of the shock front.

  3. Son of IXION: A Steady State Centrifugally Confined Plasma for Fusion*

    NASA Astrophysics Data System (ADS)

    Hassam, Adil

    1996-11-01

    A magnetic confinement scheme in which the inertial, u.grad(u), forces effect parallel confinement is proposed. The basic geometry is mirror-like as far as the poloidal field goes or, more simply, multipole (FM-1) type. The rotation is toroidal in this geometry. A supersonic rotation can effect complete parallel confinement, with the usual magnetic mirror force rendered irrelevant. The rotation shear, in addition, aids in the suppression of the flute mode. This suppression is not complete which indicates the addition of a toroidal field, at maximum of the order of the poloidal field. We show that at rotation in excess of Mach 3, the parallel particle and heat losses can be minimized to below the Lawson breakeven point. The crossfield transport can be expected to be better than tokamaks on account of the large velocity shear. Other advantages of the scheme are that it is steady state and disruption free. An exploratory experiment that tests equilibrium, parallel detachment, and MHD stability is proposed. The concept resembles earlier (Geneva, 1958) experiments on "homopolar generators" and a mirror configuration called IXION. Ixion, Greek mythological king, was forever strapped to a rotating, flaming wheel. *Work supported by DOE

  4. High illumination uniformity scheme with 32 beams configuration for direct-drive inertial confinement fusion

    NASA Astrophysics Data System (ADS)

    Li, Li; Gu, Chun; Xu, Lixin; Zhou, Shenlei

    2016-04-01

    The self-adapting algorithms are improved to optimize a beam configuration in the direct drive laser fusion system with the solid state lasers. A configuration of 32 laser beams is proposed for achieving a high uniformity illumination, with a root-mean-square deviation at 10-4 level. In our optimization, the parameters such as beam number, beam arrangement, and beam intensity profile are taken into account. The illumination uniformity robustness versus the parameters such as intensity profile deviations, power imbalance, intensity profile noise, the pointing error, and the target position error is also discussed. In this study, the model is assumed a solid-sphere illumination, and refraction effects of incident light on the corona are not considered. Our results may have a potential application in the design of the direct-drive laser fusion of the Shen Guang-II Upgrading facility (SG-II-U, China).

  5. Inertial confinement fusion quarterly report, October--December 1992. Volume 3, No. 1

    SciTech Connect

    Dixit, S.N.

    1992-12-31

    This report contains papers on the following topics: The Beamlet Front End: Prototype of a new pulse generation system;imaging biological objects with x-ray lasers; coherent XUV generation via high-order harmonic generation in rare gases; theory of high-order harmonic generation; two-dimensional computer simulations of ultra- intense, short-pulse laser-plasma interactions; neutron detectors for measuring the fusion burn history of ICF targets; the recirculator; and lasnex evolves to exploit computer industry advances.

  6. Investigation of electron-beam charging for inertial-confinement-fusion targets. Charged Particle Research Laboratory report No. 3-82

    SciTech Connect

    Kim, K.; Elsayed-Ali, H.E.

    1982-04-01

    Techniques for charging inertial confinement fusion targets using electron beam are investigated. A brief review of the various possible charging techniques is presented, along with a discussion of the advantages and disadvantages of each. The reasons for selecting the electron beam charging and a physical picture of the charging mechanism are described. Experimental results are presented and compared with the theoretical predictions.

  7. Accessible Passively Stored Highly Spin-Polarized Deuterium in Solid Hydrogen Deuterium, with Application to Inertially Confined Fusion

    NASA Astrophysics Data System (ADS)

    Alexander, Neil Brooks

    1992-01-01

    Highly spin-polarized D in solid HD was produced in a dilution refrigerator-magnet system under conditions whereby the polarization remains high upon removal of the sample to a 1K, modest field (~0.1 T) environment. This retained polarization remains for many hours to days, sufficient to allow the polarized material to be transported to distant locations and utilized there. The first intended application of this system is for inertially confined fusion (ICF) experiments with spin-polarized D fuel. The actual (vector) polarization attained thus far is P^{rm D} = 38%. The maximum D polarization obtainable with our present refrigerator and magnet (8 mK and 13 T) is 61%. The difference is due to our reluctance to wait the full time constants in these demonstration experiments and due to the inability to attain full efficiency in radio-frequency dynamic polarization transfer between D and H, the maximum polarizability of the latter in our system equaling about 85%. In addition to implementation of the polarization method, it was also necessary to develop methods for cold (4 K) sample transfer with engagement and disengagement provisions for the dilution-refrigerator apparatus, a storage -transport cryostat, various sample-preparation and diagnostic apparatuses, and an interface to an experimental destination facility, in the present case, the OMEGA fusion chamber at the University of Rochester's Laboratory for Laser Energetics. The nature of the fusion experiments required designing and constructing a complex mating system with interchange of cold shrouds to ascertain the sample was always shielded from room temperature black body radiation, and still provide means for positioning the target to within a few microns of the intersection of the high power laser beams. Means of filling plastic target shells to high pressure (at room temperature) with our special isotopic composition of HD with H_2 and D_2 impurities, and condensing them at cryogenic temperatures, were also

  8. Process for manufacture of inertial confinement fusion targets and resulting product

    DOEpatents

    Masnari, Nino A.; Rensel, Walter B.; Robinson, Merrill G.; Solomon, David E.; Wise, Kensall D.; Wuttke, Gilbert H.

    1982-01-01

    An ICF target comprising a spherical pellet of fusion fuel surrounded by a concentric shell; and a process for manufacturing the same which includes the steps of forming hemispheric shells of a silicon or other substrate material, adhering the shell segments to each other with a fuel pellet contained concentrically therein, then separating the individual targets from the parent substrate. Formation of hemispheric cavities by deposition or coating of a mold substrate is also described. Coatings or membranes may also be applied to the interior of the hemispheric segments prior to joining.

  9. Elliptical magnetic mirror generated via resistivity gradients for fast ignition inertial confinement fusion

    NASA Astrophysics Data System (ADS)

    Robinson, A. P. L.; Schmitz, H.

    2013-06-01

    The elliptical magnetic mirror scheme for guiding fast electrons for Fast Ignition proposed by Schmitz et al. (Plasma Phys. Controlled Fusion 54, 085016 (2012)) is studied for conditions on the multi-kJ scale which are much closer to full-scale Fast Ignition. When scaled up, the elliptical mirror scheme is still highly beneficial to Fast Ignition. An increase in the coupling efficiency by a factor of 3-4 is found over a wide range of fast electron divergence half-angles.

  10. Elliptical magnetic mirror generated via resistivity gradients for fast ignition inertial confinement fusion

    SciTech Connect

    Robinson, A. P. L.; Schmitz, H.

    2013-06-15

    The elliptical magnetic mirror scheme for guiding fast electrons for Fast Ignition proposed by Schmitz et al. (Plasma Phys. Controlled Fusion 54, 085016 (2012)) is studied for conditions on the multi-kJ scale which are much closer to full-scale Fast Ignition. When scaled up, the elliptical mirror scheme is still highly beneficial to Fast Ignition. An increase in the coupling efficiency by a factor of 3–4 is found over a wide range of fast electron divergence half-angles.

  11. Axial growth and fusion of liposome regulated by macromolecular crowding and confinement.

    PubMed

    Liu, Yun; Zhu, Lin; Yang, Jingfa; Sun, Jianbo; Zhao, Jiang; Liang, Dehai

    2015-05-01

    The endomembrane system, including the endoplasmic reticulum, Golgi apparatus, lysosomes, and endosomes, is located in the crowded intracellular environment. An understanding of the cellular structure and functions requires knowledge of how macromolecular crowding and confinement affect the activity of membrane and its proteins. Using negatively charged liposome and the peptide K3L8K3 as a model system, we studied the aggregation behavior of liposome in a matrix of polyacrylamide and hyaluronic acid. Without matrix, the liposomes form spherical aggregates in the presence of K3L8K3. However, they orient in one dimension and fuse into a tube up to 40 μm long in the matrix. The growth of the tube is via end-to-end connection. This anisotropic growth is mainly due to the macromolecular confinement provided by the polymer network. The study of the interactions between liposome and peptide in the crowded environment helps to reveal the mechanism of membrane-related processes in vivo. PMID:25874379

  12. Report of the Integrated Program Planning Activity for the DOE Fusion Energy Sciences Program

    SciTech Connect

    2000-12-01

    This report of the Integrated Program Planning Activity (IPPA) has been prepared in response to a recommendation by the Secretary of Energy Advisory Board that, ''Given the complex nature of the fusion effort, an integrated program planning process is an absolute necessity.'' We, therefore, undertook this activity in order to integrate the various elements of the program, to improve communication and performance accountability across the program, and to show the inter-connectedness and inter-dependency of the diverse parts of the national fusion energy sciences program. This report is based on the September 1999 Fusion Energy Sciences Advisory Committee's (FESAC) report ''Priorities and Balance within the Fusion Energy Sciences Program''. In its December 5,2000, letter to the Director of the Office of Science, the FESAC has reaffirmed the validity of the September 1999 report and stated that the IPPA presents a framework and process to guide the achievement of the 5-year goals listed in the 1999 report. The National Research Council's (NRC) Fusion Assessment Committee draft final report ''An Assessment of the Department of Energy's Office of Fusion Energy Sciences Program'', reviewing the quality of the science in the program, was made available after the IPPA report had been completed. The IPPA report is, nevertheless, consistent with the recommendations in the NRC report. In addition to program goals and the related 5-year, 10-year, and 15-year objectives, this report elaborates on the scientific issues associated with each of these objectives. The report also makes clear the relationships among the various program elements, and cites these relationships as the reason why integrated program planning is essential. In particular, while focusing on the science conducted by the program, the report addresses the important balances between the science and energy goals of the program, between the MFE and IFE approaches, and between the domestic and international aspects

  13. Core conditions for alpha heating attained in direct-drive inertial confinement fusion

    DOE PAGESBeta

    Bose, A.; Woo, K. M.; Betti, R.; Campbell, E. M.; Mangino, D.; Christopherson, A. R.; McCrory, R. L.; Nora, R.; Regan, S. P.; Goncharov, V. N.; et al

    2016-07-07

    Here, it is shown that direct-drive implosions on the OMEGA laser have achieved core conditions that would lead to significant alpha heating at incident energies available on the National Ignition Facility (NIF) scale. The extrapolation of the experimental results from OMEGA to NIF energy assumes only that the implosion hydrodynamic efficiency is unchanged at higher energies. This approach is independent of the uncertainties in the physical mechanism that degrade implosions on OMEGA, and relies solely on a volumetric scaling of the experimentally observed core conditions. It is estimated that the current best-performing OMEGA implosion [Regan et al., Phys. Rev. Lett.more » 117, 025001 (2016)] extrapolated to a 1.9 MJ laser driver with the same illumination configuration and laser-target coupling would produce 125 kJ of fusion energy with similar levels of alpha heating observed in current highest performing indirect-drive NIF implosions.« less

  14. Numerical Raytrace Verification of Optical Diagnostics of Ice Surface Roughness for Inertial Confinement Fusion Experiments

    SciTech Connect

    Koch, Jeffrey A.; Bernat, Thomas P.; Collins, Gilbert W.; Hammel, Bruce A.; MacKinnon, Andrew J.; Still, Charles H.; Sater, James D.; Bittner, Donald N

    2003-01-15

    Targets for future laser-fusion ignition experiments will consist of a frozen deuterium-tritium ice layer adhering to the inner surface of a spherical shell, and the specifications for the inner surface quality of this ice layer are extremely demanding. We have developed a numerical raytrace model in order to validate backlit optical shadowgraphy as an ice-surface diagnostic, and we have used the code to simulate shadowgraph data obtained from mathematical ice layers having known modal imperfections. We find that backlit optical shadowgraphy is a valid diagnostic of the mode spectrum of ice-surface imperfections for mode numbers as high as 80 provided the experimental data are analyzed appropriately. We also describe alternative measurement techniques, which may be more sensitive than conventional backlit shadowgraphy.

  15. Symmetric inertial confinement fusion implosions at ultra-high laser energies

    SciTech Connect

    Glenzer, S H; MacGowan, B J; Michel, P; Meezan, N B; Suter, L J; Dixit, S N; Kline, J L; Kyrala, G A; Callahan, D A; Dewald, E L; Divol, L; Dzenitis, E; Edwards, J; Hamza, A V; Haynam, C A; Hinkel, D E; Kalantar, D H; Kilkenny, J D; Landen, O L; Lindle, J D; LePape, S; Moody, J D; Nikroo, A; Parham, T; Schneider, M B; Town, R J; Wegner, P; Widmann, K; Whitman, P; Young, B F; Van Wonterghem, B; Atherton, J E; Moses, E I

    2009-12-03

    The first indirect-drive hohlraum experiments at the National Ignition Facility have demonstrated symmetric capsule implosions at unprecedented laser drive energies of 0.7 MJ. 192 simultaneously fired laser beams heat ignition hohlraums to radiation temperatures of 3.3 million Kelvin compressing 1.8-millimeter capsules by the soft x rays produced by the hohlraum. Self-generated plasma-optics gratings on either end of the hohlraum tune the laser power distribution in the hohlraum producing symmetric x-ray drive as inferred from capsule self-emission measurements. These experiments indicate conditions suitable for compressing deuterium-tritium filled capsules with the goal to achieve burning fusion plasmas and energy gain in the laboratory.

  16. Symmetric inertial confinement fusion implosions at ultra-high laser energies.

    PubMed

    Glenzer, S H; MacGowan, B J; Michel, P; Meezan, N B; Suter, L J; Dixit, S N; Kline, J L; Kyrala, G A; Bradley, D K; Callahan, D A; Dewald, E L; Divol, L; Dzenitis, E; Edwards, M J; Hamza, A V; Haynam, C A; Hinkel, D E; Kalantar, D H; Kilkenny, J D; Landen, O L; Lindl, J D; LePape, S; Moody, J D; Nikroo, A; Parham, T; Schneider, M B; Town, R P J; Wegner, P; Widmann, K; Whitman, P; Young, B K F; Van Wonterghem, B; Atherton, L J; Moses, E I

    2010-03-01

    Indirect-drive hohlraum experiments at the National Ignition Facility have demonstrated symmetric capsule implosions at unprecedented laser drive energies of 0.7 megajoule. One hundred and ninety-two simultaneously fired laser beams heat ignition-emulate hohlraums to radiation temperatures of 3.3 million kelvin, compressing 1.8-millimeter-diameter capsules by the soft x-rays produced by the hohlraum. Self-generated plasma optics gratings on either end of the hohlraum tune the laser power distribution in the hohlraum, which produces a symmetric x-ray drive as inferred from the shape of the capsule self-emission. These experiments indicate that the conditions are suitable for compressing deuterium-tritium-filled capsules, with the goal of achieving burning fusion plasmas and energy gain in the laboratory. PMID:20110465

  17. Core conditions for alpha heating attained in direct-drive inertial confinement fusion

    NASA Astrophysics Data System (ADS)

    Bose, A.; Woo, K. M.; Betti, R.; Campbell, E. M.; Mangino, D.; Christopherson, A. R.; McCrory, R. L.; Nora, R.; Regan, S. P.; Goncharov, V. N.; Sangster, T. C.; Forrest, C. J.; Frenje, J.; Gatu Johnson, M.; Glebov, V. Yu; Knauer, J. P.; Marshall, F. J.; Stoeckl, C.; Theobald, W.

    2016-07-01

    It is shown that direct-drive implosions on the OMEGA laser have achieved core conditions that would lead to significant alpha heating at incident energies available on the National Ignition Facility (NIF) scale. The extrapolation of the experimental results from OMEGA to NIF energy assumes only that the implosion hydrodynamic efficiency is unchanged at higher energies. This approach is independent of the uncertainties in the physical mechanism that degrade implosions on OMEGA, and relies solely on a volumetric scaling of the experimentally observed core conditions. It is estimated that the current best-performing OMEGA implosion [Regan et al., Phys. Rev. Lett. 117, 025001 (2016), 10.1103/PhysRevLett.117.025001] extrapolated to a 1.9 MJ laser driver with the same illumination configuration and laser-target coupling would produce 125 kJ of fusion energy with similar levels of alpha heating observed in current highest performing indirect-drive NIF implosions.

  18. Inertial Confinement Fusion quarterly report, January-March 1998, volume 8, number 2

    SciTech Connect

    Kruer, W

    1998-03-31

    The coupling of laser light with plasmas is one of the key physics issues for the use of high-power lasers for inertial fusion, high-energy-density physics, and scientific stockpile stewardship. The coupling physics is extremely rich and challenging, particularly in the large plasmas to be accessed on the National Ignition Facility (NIF). The coupling mechanisms span the gamut from classical inverse bremsstrahlung absorption to a variety of nonlinear optical processes. These include stimulated Raman scattering (SRS) from electron plasma waves, stimulated Brillouin scattering (SBS) from ion sound waves, resonant decay into electron plasma and ion sound waves, and laser beam filamentation. These processes depend on laser intensity and produce effects such as changes in the efficiency and location of the energy deposition or generation of a component of very energetic electrons, which can preheat capsules. Coupling physics issues have an extremely high leverage. The coupling models are clearly very important ingredients for detailed calculations of laser-irradiated target behavior. Improved understanding and models enable a more efficient use of laser facilities, which becomes even more important as these facilities become larger and more expensive. Advances in the understanding also allow a more timely and cost-effective identification of new applications of high-power lasers, such as for generation of high-temperature hohlraums and compact x-ray sources, or for discovery of advanced fusion schemes. Finally, the interaction of intense electromagnetic waves with ionized media is a fundamental topic of interest to numerous areas of applied science and is an excellent test bed for advancing plasma science and computational modeling of complex phenomena. This issue of the ICF Quarterly Report is dedicated to laser--plasma interactions. The eight articles present a cross section of the broad progress in understanding the key interaction issues, such as laser beam bending

  19. The need for a fusion technology information program

    SciTech Connect

    Correll, D.L. Jr.

    1987-06-16

    In providing an adequate energy technology for the future, which new programs should be considered by the Department of Energy national laboratories to ensure that the US remains in the forefront of international science and technology is an important question. This paper suggests that the urgency for energy independence demands an active communication program that would increase awareness of energy as a critical national issue and would present fusion, with its benefits and risks, as one of the long-term alternative energy sources.

  20. Magnetic Fusion Science Fellowship program: Summary of program activities for calendar year 1986

    SciTech Connect

    Not Available

    1986-01-01

    This report describes the 1985-1986 progress of the Magnetic Fusion Science Fellowship program (MFSF). The program was established in January of 1985 by the Office of Fusion Energy (OFE) of the US Department of Energy (DOE) to encourage talented undergraduate and first-year graduate students to enter qualified graduate programs in the sciences related to fusion energy development. The program currently has twelve fellows in participating programs. Six new fellows are being appointed during each of the program's next two award cycles. Appointments are for one year and are renewable for two additional years with a three year maximum. The stipend level also continues at a $1000 a month or $12,000 a year. The program pays all tuition and fee expenses for the fellows. Another important aspect of the fellowship program is the practicum. During the practicum fellows receive three month appointments to work at DOE designated fusion science research and development centers. The practicum allows the MFSF fellows to directly participate in on-going DOE research and development programs.

  1. A carbon-carbon composite materials development program for fusion energy applications

    SciTech Connect

    Burchell, T.D.; Eatherly, W.P. ); Engle, G.B. ); Hollenberg, G.W. )

    1992-10-01

    Carbon-carbon composites increasingly are being used for plasma-facing component (PFC) applications in magnetic-confinement plasma-fusion devices. They offer substantial advantages such as enhanced physical and mechanical properties and superior thermal shock resistance compared to the previously favored bulk graphite. Next-generation plasma-fusion reactors, such as the International Thermonuclear Experimental Reactor (ITER) and the Burning Plasma Experiment (BPX), will require advanced carbon-carbon composites possessing extremely high thermal conductivity to manage the anticipated extreme thermal heat loads. This report outlines a program that will facilitate the development of advanced carbon-carbon composites specifically tailored to meet the requirements of ITER and BPX. A strategy for developing the necessary associated design data base is described. Materials property needs, i.e., high thermal conductivity, radiation stability, tritium retention, etc., are assessed and prioritized through a systems analysis of the functional, operational, and component requirements for plasma-facing applications. The current Department of Energy (DOE) Office of Fusion Energy Program on carbon-carbon composites is summarized. Realistic property goals are set based upon our current understanding. The architectures of candidate PFC carbon-carbon composite materials are outlined, and architectural features considered desirable for maximum irradiation stability are described. The European and Japanese carbon-carbon composite development and irradiation programs are described. The Working Group conclusions and recommendations are listed. It is recommended that developmental carbon-carbon composite materials from the commercial sector be procured via request for proposal/request for quotation (RFP/RFQ) as soon as possible.

  2. Dynamic response of materials on sub-nanosecond time scales, and beryllium properties for inertial confinement fusion

    SciTech Connect

    Swift, D C; Tierney, T E; Luo, S N; Paisley, D L; Kyrala, G A; Hauer, A; Greenfield, S R; Koskelo, A C; McClellan, K J; Lorenzana, H E; Knudson, M D; Peralta, P P; Loomis, E

    2004-12-09

    During the past few years, substantial progress has been made in developing experimental techniques capable of investigating the response of materials to dynamic loading on nanosecond time scales and shorter, with multiple diagnostics probing different aspects of the behavior. these relatively short time scales are scientifically interesting because plastic flow and phase changes in common materials with simple crystal structures--such as iron--may be suppressed, allowing unusual states to be induced and the dynamics of plasticity and polymorphism to be explored. Loading by laser ablation can be particularly convenient. The TRIDENT laser has been used to impart shocks and isentropic compression waves from {approx}1 to 200GPa in a range of elements and alloys, with diagnostics including surface velocimetry (line-imaging VISAR), surface displacement (framed area imaging), x-ray diffraction (single crystal and polycrystal), ellipsometry, and Raman spectroscopy. A major motivation has been the study of the properties of beryllium under conditions relevant to the fuel capsule in inertial confinement fusion: magnetically-driven shock and isentropic compression shots at Z were used to investigate the equation of state and shock melting characteristics, complemented by laser ablation experiments to investigate plasticity and heterogeneous response. These results will help to constrain acceptable tolerances on manufacturing, and possible loading paths, for inertial fusion ignition experiments at the National Ignition Facility. Laser-based techniques are being developed further for future material dynamics experiments, where it should be possible to obtain high quality data on strength and phase changes up to at least 1TPa.

  3. Accessible passively stored highly spin-polarized D in solid HD, with application to inertially confined fusion

    SciTech Connect

    Alexander, N.B.

    1992-01-01

    Highly spin-polarized D in solid HD was produced in a dilution refrigerator-magnet system under conditions whereby the polarization remains high upon removal of the sample to a 1K, modest field ([approximately]0.1 T) environment. This retained polarization remains for many hours to days. The first intended application of this system is for inertially confined fusion (ICF) experiments with spin-polarized D fuel. The actual (vector) polarization attained thus far is P[sup D] = 38%. The maximum D polarization obtainable with the present refrigerator and magnet (8 mK and 13 T) is 61%. The difference is due to the author's reluctance to wait the full time constants in these demonstration experiments and due to the inability to attain full efficiency in radio-frequency dynamic polarization transfer between D and H, the maximum polarizability of the latter in the system equaling about 85%. It was necessary to develop methods for cold (4 K) sample transfer with engagement and disengagement provisions for the dilution-refrigerator apparatus, a storage-transport cryostat, various sample-preparation and diagnostic apparatus, and an interface to an experimental destination facility. The nature of the fusion experiments required designing and constructing a complex mating system with interchange of cold shrouds to ascertain the sample was always shielded from room temperature black body radiation, and still provide means for positioning the target to within a few microns of the intersection of the high power laser beams. Means of filling plastic target shells to high pressure with the special isotopic composition of HD with H[sub 2]and D[sub 2] impurities, and condensing them at cryogenic temperatures, were also perfected.

  4. Core conditions for alpha heating attained in direct-drive inertial confinement fusion.

    PubMed

    Bose, A; Woo, K M; Betti, R; Campbell, E M; Mangino, D; Christopherson, A R; McCrory, R L; Nora, R; Regan, S P; Goncharov, V N; Sangster, T C; Forrest, C J; Frenje, J; Gatu Johnson, M; Glebov, V Yu; Knauer, J P; Marshall, F J; Stoeckl, C; Theobald, W

    2016-07-01

    It is shown that direct-drive implosions on the OMEGA laser have achieved core conditions that would lead to significant alpha heating at incident energies available on the National Ignition Facility (NIF) scale. The extrapolation of the experimental results from OMEGA to NIF energy assumes only that the implosion hydrodynamic efficiency is unchanged at higher energies. This approach is independent of the uncertainties in the physical mechanism that degrade implosions on OMEGA, and relies solely on a volumetric scaling of the experimentally observed core conditions. It is estimated that the current best-performing OMEGA implosion [Regan et al., Phys. Rev. Lett. 117, 025001 (2016)10.1103/PhysRevLett.117.025001] extrapolated to a 1.9 MJ laser driver with the same illumination configuration and laser-target coupling would produce 125 kJ of fusion energy with similar levels of alpha heating observed in current highest performing indirect-drive NIF implosions. PMID:27575069

  5. Computational study of laser imprint mitigation in foam-buffered inertial confinement fusion targets

    SciTech Connect

    Mason, R.J.; Kopp, R.A.; Vu, H.X.; Wilson, D.C.; Goldman, S.R.; Watt, R.G.; Dunne, M.; Willi, O.

    1998-01-01

    Recent experiments have shown that low density foam layers can significantly mitigate the perturbing effects of beam nonuniformities affecting the acceleration of thin shells. This problem is studied parametrically with two-dimensional LASNEX [G. B. Zimmerman and W. L. Kruer, Comments Plasma Phys. Controlled Fusion {bold 2}, 51 (1975)]. Foam-buffered targets are employed, consisting typically of 250 {Angstrom} of gold, and 50 {mu}m of 50mg/cm{sup 3} C{sub 10}H{sub 8}O{sub 4} foam attached to a 10 {mu}m foil. In simulation these were characteristically exposed to 1.2 ns, flat-topped green light pulses at 1.4{times}10{sup 14}W/cm{sup 2} intensity, bearing 30 {mu}m lateral perturbations of up to 60{percent} variation in intensity. Without the buffer layers the foils were severely disrupted by 1 ns. With buffering only minimal distortion was manifest at 3 ns. The smoothing is shown to derive principally from the high thermal conductivity of the heated foam. The simulation results imply that (1) the foam thickness should exceed the disturbance wavelength; (2) intensities exceeding 5{times}10{sup 13}W/cm{sup 2} are needed for assured stability beyond 2 ns; (3) longer foams at lower densities are needed for effective mitigation with shorter wavelength light; (4) the gold layer hastens conversion of the structured foam to a uniform plasma. {copyright} {ital 1998 American Institute of Physics.}

  6. High-adiabat high-foot inertial confinement fusion implosion experiments on the national ignition facility.

    PubMed

    Park, H-S; Hurricane, O A; Callahan, D A; Casey, D T; Dewald, E L; Dittrich, T R; Döppner, T; Hinkel, D E; Berzak Hopkins, L F; Le Pape, S; Ma, T; Patel, P K; Remington, B A; Robey, H F; Salmonson, J D; Kline, J L

    2014-02-01

    This Letter reports on a series of high-adiabat implosions of cryogenic layered deuterium-tritium (DT) capsules indirectly driven by a "high-foot" laser drive pulse at the National Ignition Facility. High-foot implosions have high ablation velocities and large density gradient scale lengths and are more resistant to ablation-front Rayleigh-Taylor instability induced mixing of ablator material into the DT hot spot. Indeed, the observed hot spot mix in these implosions was low and the measured neutron yields were typically 50% (or higher) of the yields predicted by simulation. On one high performing shot (N130812), 1.7 MJ of laser energy at a peak power of 350 TW was used to obtain a peak hohlraum radiation temperature of ∼300  eV. The resulting experimental neutron yield was (2.4±0.05)×10(15) DT, the fuel ρR was (0.86±0.063)  g/cm2, and the measured Tion was (4.2±0.16)  keV, corresponding to 8 kJ of fusion yield, with ∼1/3 of the yield caused by self-heating of the fuel by α particles emitted in the initial reactions. The generalized Lawson criteria, an ignition metric, was 0.43 and the neutron yield was ∼70% of the value predicted by simulations that include α-particle self-heating. PMID:24580603

  7. Z pinches as intense x-ray sources for inertial confinement fusion applications

    SciTech Connect

    Matzen, M.K.

    1997-05-01

    Fast z-pinch implosions can convert more than 10% of the stored electrical energy in a pulsed-power accelerator into x-rays. On the Saturn pulsed-power accelerator at Sandia National Laboratories, currents of 6 to 8 MA with a risetime of less than 50 ns have been used to drive cylindrically-symmetric arrays of wires, producing x-ray energies greater than 400 kJ with x-ray pulsewidths less than 5 ns and peak x-ray powers of 75 {+-} 10 TW. Using similar loads, PBFA Z has produced > 1.5 MJ and > 150 TW of x-rays in the first four months of operation in the z-pinch mode. These x-ray energies and powers are records for laboratory x-ray production. The x-ray output can be thermalized into a near-Planckian x-ray source by containing it within a cylindrical radiation case (a hohlraum). These energetic, intense, large volume, long-lived hohlraum x-ray sources have recently been used for ICF-relevant ablator physics experiments and offer the potential for performing many new basic physics and fusion-relevant experiments.

  8. Effects of Laser-Plasma Instabilities on Hydro Evolution in Direct-Drive Inertial Confinement Fusion

    NASA Astrophysics Data System (ADS)

    Li, J.; Hu, S. X.; Ren, C.

    2015-11-01

    Laser-plasma instabilities and hydro evolution of coronal plasmas in an OMEGA EP long-scale-length experiment with planar targets are studied with particle-in-cell (PIC) and hydrodynamics simulations. Plasma and laser conditions are first obtained in a DRACO simulation with only inverse-bremsstrahlung absorption. Using these conditions, an OSIRIS simulation is performed to study laser absorption and hot-electron generation caused by laser-plasma instabilities near the quarter-critical region. The obtained PIC information has subsequently been coupled to another DRACO simulation to examine how the laser-plasma instabilities affect the overall hydrodynamics. The results show that the more-realistic laser absorption can increase the electron temperature but only slightly changes the density scale length in the corona. This material is based upon work supported by the Department of Energy National Nuclear Security Administration under Award Number DE-NA0001944, DE-FC02-04ER54789 (Fusion Science Center), and DE-SC0012316.

  9. Spatially resolved high resolution x-ray spectroscopy for magnetically confined fusion plasmas (invited)

    SciTech Connect

    Ince-Cushman, A.; Rice, J. E.; Reinke, M. L.; Podpaly, Y.; Marmar, E. S.; Bitter, M.; Hill, K. W.; Scott, S.; Gu, M. F.; Eikenberry, E.; Broennimann, Ch.; Lee, S. G.

    2008-10-15

    The use of high resolution x-ray crystal spectrometers to diagnose fusion plasmas has been limited by the poor spatial localization associated with chord integrated measurements. Taking advantage of a new x-ray imaging spectrometer concept [M. Bitter et al., Rev. Sci. Instrum. 75, 3660 (2004)], and improvements in x-ray detector technology [Ch. Broennimann et al., J. Synchrotron Radiat. 13, 120 (2006)], a spatially resolving high resolution x-ray spectrometer has been built and installed on the Alcator C-Mod tokamak. This instrument utilizes a spherically bent quartz crystal and a set of two dimensional x-ray detectors arranged in the Johann configuration [H. H. Johann, Z. Phys. 69, 185 (1931)] to image the entire plasma cross section with a spatial resolution of about 1 cm. The spectrometer was designed to measure line emission from H-like and He-like argon in the wavelength range 3.7 and 4.0 A with a resolving power of approximately 10 000 at frame rates up to 200 Hz. Using spectral tomographic techniques [I. Condrea, Phys. Plasmas 11, 2427 (2004)] the line integrated spectra can be inverted to infer profiles of impurity emissivity, velocity, and temperature. From these quantities it is then possible to calculate impurity density and electron temperature profiles. An overview of the instrument, analysis techniques, and example profiles are presented.

  10. Molecular Dynamics Investigations of the Ablator/Fuel Interface during Early Stages of Inertial Confinement Fusion

    NASA Astrophysics Data System (ADS)

    Stanton, Liam; Murillo, Michael; Glosli, James

    2014-10-01

    At the National Ignition Facility, high-powered laser beams are used to compress a small target to generate fusion reactions. A critical issue in achieving this is the understanding of mix at the ablator/fuel interface. Mixing occurs at various length scales, ranging from atomic inter-species diffusion to hydrodynamic instabilities. Because the interface is preheated by energy from the incoming shock, it is important to understand the dynamics before the shock arrives. The interface is in the warm dense matter phase with a deuterium/tritium fuel mixture on one side and a plastic mixture on the other. We would like to understand various aspects of the evolution, including the state of the interface when the main shock arrives, the role of electric field generation at the interface, and the character and time scales for diffusion. We present a molecular dynamics approach to model these processes, in which the ions are treated as classical point particles. Because we must reach extremely large length and time scales, we have also developed a simplified electronic structure model, which includes time- and space-dependent ionization levels, external heating and electron-ion energy exchange. Simulation results are presented and compared with other models and experiments. This work was performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344.

  11. High-speed repetitive pellet injector for plasma fueling of magnetic confinement fusion devices

    SciTech Connect

    Combs, S.K.; Baylor, L.R.; Foust, C.R.

    1993-11-01

    The projected fueling requirements of future magnetic confinement devices for controlled thermonuclear research [e.g., the International Thermonuclear Experimental Reactor (ITER)] indicate that a flexible plasma fueling capability is required. This includes a mix of traditional gas puffing and low- and high-velocity deuterium-tritium pellets. Conventional pellet injectors (based on light gas guns or centrifugal accelerators) can reliably provide frozen hydrogen pellets (1- to 6-mm-diam sizes tested) up to {approximately}1.3-km/s velocity at the appropriate pellet fueling rates (1 to 10 Hz or greater). For long-pulse operation in a higher velocity regime (>2 km/s), an experiment in collaboration between Oak Ridge National Laboratory (ORNL) and ENEA Frascati is under way. This activity will be carried out in the framework of a collaborative agreement between the US Department of Energy and European Atomic Energy Community -- ENEA Association. In this experiment, an existing ORNL hydrogen extruder (equipped with a pellet chambering mechanism/gun barrel assembly) and a Frascati two-stage light gas gun driver have been combined on a test facility at ORNL. Initial testing has been carried out with single deuterium pellets accelerated up to 2.05 km/s with the two-stage driver; in addition, some preliminary repetitive testing (to commission the diagnostics) was performed at reduced speeds, including sequences at 0.5 to 1 Hz and 10 to 30 pellets. The primary objective of this study is to demonstrate repetitive operation (up to {approximately}1 Hz) with speeds in the 2- to 3-km/s range. In addition, the strength of extruded hydrogen ice as opposed to that produced in situ by direct condensation in pipe guns can be investigated. The equipment and initial experimental results are described.

  12. Inertial confinement fusion using hohlraum radiation generated by heavy-ion clusters

    NASA Astrophysics Data System (ADS)

    Tahir, N. A.; Lutz, K.-J.; Geb, O.; Maruhn, J. A.; Deutsch, C.; Hoffmann, D. H. H.

    1997-03-01

    This paper discusses the feasibility of employing heavy-ion cluster beams to generate thermal radiation that can be used to drive inertial fusion capsules. The low charge-to-mass ratio of a cluster may allow the driver beam to be focused to a very small spot size with a radius of the order of 100 μm, while the low energy per nucleon (of the order of 10 keV) may lead to a very short range of the driver particles in the converter material. This would result in high specific power deposition that may lead to a very high conversion efficiency. The problem of cluster stopping in cold matter, as well as in hot dense plasmas has been thoroughly investigated. The conversion efficiency of cluster ions using a low-density gold converter has also been calculated over a wide range of parameters including converter density, converter geometry, and specific power deposition. These calculations have been carried out using a one-dimensional hydrodynamic computer code that includes a multigroup radiation transport scheme [Ramis et al., Comput. Phys. Commun. 49, 475 (1988)]. The problem of symmetrization of this radiation field in a hohlraum with solid gold walls has also been thoroughly investigated using a three-dimensional view factor code. The characteristics of the radiation field obtained by this study are used as input to capsule implosion calculations that are done with a three-temperature radiation-hydrodynamic computer code MEDUSA-KAT [Tahir et al., J. Appl. Phys. 60, 898 (1986)]. A reactor-size capsule which contains 5 mg deuterium-tritium (DT) fuel is used in these calculations. The problem of using a fuel mixture with a substantially reduced tritium content has also been discussed.

  13. Tools for Predicting Optical Damage on Inertial Confinement Fusion-Class Laser Systems

    SciTech Connect

    Nostrand, M C; Carr, C W; Liao, Z M; Honig, J; Spaeth, M L; Manes, K R; Johnson, M A; Adams, J J; Cross, D A; Negres, R A; Widmayer, C C; Williams, W H; Matthews, M J; Jancaitis, K S; Kegelmeyer, L M

    2010-12-20

    Operating a fusion-class laser to its full potential requires a balance of operating constraints. On the one hand, the total laser energy delivered must be high enough to give an acceptable probability for ignition success. On the other hand, the laser-induced optical damage levels must be low enough to be acceptably handled with the available infrastructure and budget for optics recycle. Our research goal was to develop the models, database structures, and algorithmic tools (which we collectively refer to as ''Loop Tools'') needed to successfully maintain this balance. Predictive models are needed to plan for and manage the impact of shot campaigns from proposal, to shot, and beyond, covering a time span of years. The cost of a proposed shot campaign must be determined from these models, and governance boards must decide, based on predictions, whether to incorporate a given campaign into the facility shot plan based upon available resources. Predictive models are often built on damage ''rules'' derived from small beam damage tests on small optics. These off-line studies vary the energy, pulse-shape and wavelength in order to understand how these variables influence the initiation of damage sites and how initiated damage sites can grow upon further exposure to UV light. It is essential to test these damage ''rules'' on full-scale optics exposed to the complex conditions of an integrated ICF-class laser system. Furthermore, monitoring damage of optics on an ICF-class laser system can help refine damage rules and aid in the development of new rules. Finally, we need to develop the algorithms and data base management tools for implementing these rules in the Loop Tools. The following highlights progress in the development of the loop tools and their implementation.

  14. LDRD final report on confinement of cluster fusion plasmas with magnetic fields.

    SciTech Connect

    Argo, Jeffrey W.; Kellogg, Jeffrey W.; Headley, Daniel Ignacio; Stoltzfus, Brian Scott; Waugh, Caleb J.; Lewis, Sean M.; Porter, John Larry, Jr.; Wisher, Matthew; Struve, Kenneth William; Savage, Mark Edward; Quevedo, Hernan J.; Bengtson, Roger

    2011-11-01

    Two versions of a current driver for single-turn, single-use 1-cm diameter magnetic field coils have been built and tested at the Sandia National Laboratories for use with cluster fusion experiments at the University of Texas in Austin. These coils are used to provide axial magnetic fields to slow radial loss of electrons from laser-produced deuterium plasmas. Typical peak field strength achievable for the two-capacitor system is 50 T, and 200 T for the ten-capacitor system. Current rise time for both systems is about 1.7 {mu}s, with peak current of 500 kA and 2 MA, respectively. Because the coil must be brought to the laser, the driver needs to be portable and drive currents in vacuum. The drivers are complete but laser-plasma experiments are still in progress. Therefore, in this report, we focus on system design, initial tests, and performance characteristics of the two-capacitor and ten-capacitors systems. The questions of whether a 200 T magnetic field can retard the breakup of a cluster-fusion plasma, and whether this field can enhance neutron production have not yet been answered. However, tools have been developed that will enable producing the magnetic fields needed to answer these questions. These are a two-capacitor, 400-kA system that was delivered to the University of Texas in 2010, and a 2-MA ten-capacitor system delivered this year. The first system allowed initial testing, and the second system will be able to produce the 200 T magnetic fields needed for cluster fusion experiments with a petawatt laser. The prototype 400-kA magnetic field driver system was designed and built to test the design concept for the system, and to verify that a portable driver system could be built that delivers current to a magnetic field coil in vacuum. This system was built copying a design from a fixed-facility, high-field machine at LANL, but made to be portable and to use a Z-machine-like vacuum insulator and vacuum transmission line. This system was sent to the

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

    DOEpatents

    Woolley, Robert D.

    1999-01-01

    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.

  16. Method and System to Directly Produce Electrical Power within the Lithium Blanket Region of a Magnetically Confined, Deuterium-Tritium (DT) Fueled, Thermonuclear Fusion Reactor

    SciTech Connect

    Woolley, Robert D.

    1998-09-22

    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.

  17. A 1.5-4 K detachable cold-sample transfer system: Application to inertially confined fusion with spin-polarized hydrogen fuels

    NASA Astrophysics Data System (ADS)

    Alexander, N.; Barden, J.; Fan, Q.; Honig, A.

    1991-11-01

    A compact cold-transfer apparatus for engaging and retrieving samples at liquid-helium temperatures (1.5-4 K), maintaining the samples at such temperatures for periods of hours, and subsequently inserting them in diverse apparatuses followed by disengagement, is described. The properties of several thermal radiation-insulating shrouds, necessary for very low sample temperatures, are presented. The immediate intended application is transportable target shells containing highly spin-polarized deuterons in solid HD or D2 for inertially confined fusion experiments. The system is also valuable for unpolarized high-density fusion fuels, as well as for other applications which are discussed.

  18. A 1. 5--4 Kelvin detachable cold-sample transfer system: Application to inertially confined fusion with spin-polarized hydrogens fuels

    SciTech Connect

    Alexander, N.; Barden, J.; Fan, Q.; Honig, A.

    1990-01-01

    A compact cold-transfer apparatus for engaging and retrieving samples at liquid helium temperatures (1.5--4K), maintaining the samples at such temperatures for periods of hours, and subsequently inserting them in diverse apparatuses followed by disengagement, is described. The properties of several thermal radiation-insulating shrouds, necessary for very low sample temperatures, are presented. The immediate intended application is transportable target-shells containing highly spin-polarized deuterons in solid HD or D{sub 2} for inertially confined fusion (ICF) experiments. The system is also valuable for unpolarized high-density fusion fuels, as well as for other applications which are discussed. 9 refs., 6 figs.

  19. A 1.5 to 4 kelvin detachable cold-sample transfer system: Application to inertially confined fusion with spin-polarized hydrogens fuels

    NASA Astrophysics Data System (ADS)

    Alexander, N.; Barden, J.; Fan, Q.; Honig, A.

    A compact cold-transfer apparatus for engaging and retrieving samples at liquid helium temperatures (1.5 to 4 K), maintaining the samples at such temperatures for periods of hours, and subsequently inserting them in diverse apparatuses followed by disengagement, is described. The properties of several thermal radiation-insulating shrouds, necessary for very low sample temperatures, are presented. The immediate intended application is transportable target-shells containing highly spin-polarized deuterons in solid HD or D(2) for inertially confined fusion (ICF) experiments. The system is also valuable for unpolarized high-density fusion fuels, as well as for other applications which are discussed.

  20. A 1. 5--4 K detachable cold-sample transfer system: Application to inertially confined fusion with spin-polarized hydrogen fuels

    SciTech Connect

    Alexander, N.; Barden, J.; Fan, Q.; Honig, A. )

    1991-11-01

    A compact cold-transfer apparatus for engaging and retrieving samples at liquid-helium temperatures (1.5--4 K), maintaining the samples at such temperatures for periods of hours, and subsequently inserting them in diverse apparatuses followed by disengagement, is described. The properties of several thermal radiation-insulating shrouds, necessary for very low sample temperatures, are presented. The immediate intended application is transportable target shells containing highly spin-polarized deuterons in solid HD or D{sub 2} for inertially confined fusion experiments. The system is also valuable for unpolarized high-density fusion fuels, as well as for other applications which are discussed.

  1. A simulation-based and analytic analysis of the off-Hugoniot response of alternative inertial confinement fusion ablator materials

    NASA Astrophysics Data System (ADS)

    Moore, Alastair S.; Prisbrey, Shon; Baker, Kevin L.; Celliers, Peter M.; Fry, Jonathan; Dittrich, Thomas R.; Wu, Kuang-Jen J.; Kervin, Margaret L.; Schoff, Michael E.; Farrell, Mike; Nikroo, Abbas; Hurricane, Omar A.

    2016-09-01

    The attainment of self-propagating fusion burn in an inertial confinement target at the National Ignition Facility will require the use of an ablator with high rocket-efficiency and ablation pressure. The ablation material used during the National Ignition Campaign (Lindl et al. 2014) [1], a glow-discharge polymer (GDP), does not couple as efficiently as simulations indicated to the multiple-shock inducing radiation drive environment created by laser power profile (Robey et al., 2012). We investigate the performance of two other ablators, boron carbide (B4C) and high-density carbon (HDC) compared to the performance of GDP under the same hohlraum conditions. Ablation performance is determined through measurement of the shock speed produced in planar samples of the ablator material subjected to the identical multiple-shock inducing radiation drive environments that are similar to a generic three-shock ignition drive. Simulations are in better agreement with the off-Hugoniot performance of B4C than either HDC or GDP, and analytic estimations of the ablation pressure indicate that while the pressure produced by B4C and GDP is similar when the ablator is allowed to release, the pressure reached by B4C seems to exceed that of HDC when backed by a Au/quartz layer.

  2. Effects of the Ponderomotive Terms in the Thermal Transport on the Hydrodynamic Flow in Inertial Confinement Fusion Experiments

    NASA Astrophysics Data System (ADS)

    Goncharov, V. N.; Li, G.

    2004-11-01

    Electron thermal transport is significantly modified by the laser-induced electric fields near the turning point and at the critical surface. It is shown that such modifications lead to an additional limitation in the heat flux in laser-produced plasmas. Furthermore, the ponderomotive terms in the heat flux lead to a steepening in the electron-density profile, which is shown to be a larger effect than the profile modification due to the ponderomotive force [W.L. Kruer, The Physics of Laser--Plasma Interactions, Frontiers in Physics, Vol. 73, edited by D. Pines (Addison-Wesley, Redwood City, CA, 1988)]. To take into account the nonlocal effects, the delocalization model developed in Ref. 2 [G.P. Schurtz, Ph.D. Nicolaï, and M. Busquet, Phys. Plasmas 7, 4238 (2000).] has been applied to conditions relevant to ICF experiments. This work was supported by the U.S. Department of Energy Office of Inertial Confinement Fusion under Cooperative Agreement No. DE-FC52-92SF19460.

  3. Simultaneous neutron and x-ray imaging of inertial confinement fusion experiments along a single line of sight at Omega

    DOE PAGESBeta

    Danly, C. R.; Day, T. H.; Fittinghoff, D. N.; Herrmann, H.; Izumi, N.; Kim, Y. H.; Martinez, J. I.; Merrill, F. E.; Schmidt, D. W.; Simpson, R. A.; et al

    2015-04-16

    Neutron and x-ray imaging provide critical information about the geometry and hydrodynamics of inertial confinement fusion implosions. However, existing diagnostics at Omega and the National Ignition Facility (NIF) cannot produce images in both neutrons and x-rays along the same line of sight. This leads to difficulty comparing these images, which capture different parts of the plasma geometry, for the asymmetric implosions seen in present experiments. Further, even when opposing port neutron and x-ray images are available, they use different detectors and cannot provide positive information about the relative positions of the neutron and x-ray sources. A technique has been demonstratedmore » on implosions at Omega that can capture x-ray images along the same line of sight as the neutron images. Thus, the technique is described, and data from a set of experiments are presented, along with a discussion of techniques for coregistration of the various images. It is concluded that the technique is viable and could provide valuable information if implemented on NIF in the near future.« less

  4. Simultaneous neutron and x-ray imaging of inertial confinement fusion experiments along a single line of sight at Omega

    SciTech Connect

    Danly, C. R.; Day, T. H.; Herrmann, H.; Kim, Y. H.; Martinez, J. I.; Merrill, F. E.; Schmidt, D. W.; Simpson, R. A.; Volegov, P. L.; Wilde, C. H.; Fittinghoff, D. N.; Izumi, N.

    2015-04-15

    Neutron and x-ray imaging provide critical information about the geometry and hydrodynamics of inertial confinement fusion implosions. However, existing diagnostics at Omega and the National Ignition Facility (NIF) cannot produce images in both neutrons and x-rays along the same line of sight. This leads to difficulty comparing these images, which capture different parts of the plasma geometry, for the asymmetric implosions seen in present experiments. Further, even when opposing port neutron and x-ray images are available, they use different detectors and cannot provide positive information about the relative positions of the neutron and x-ray sources. A technique has been demonstrated on implosions at Omega that can capture x-ray images along the same line of sight as the neutron images. The technique is described, and data from a set of experiments are presented, along with a discussion of techniques for coregistration of the various images. It is concluded that the technique is viable and could provide valuable information if implemented on NIF in the near future.

  5. A diamond detector for inertial confinement fusion X-ray bang-time measurements at the National Ignition Facility

    SciTech Connect

    MacPhee, A G; Brown, C; Burns, S; Celeste, J; Glenzer, S H; Hey, D; Jones, O S; Landen, O; Mackinnon, A J; Meezan, N; Parker, J; Edgell, D; Glebov, V Y; Kilkenny, J; Kimbrough, J

    2010-11-09

    An instrument has been developed to measure X-ray bang-time for inertial confinement fusion capsules; the time interval between the start of the laser pulse and peak X-ray emission from the fuel core. The instrument comprises chemical vapor deposited polycrystalline diamond photoconductive X-ray detectors with highly ordered pyrolytic graphite X-ray monochromator crystals at the input. Capsule bang-time can be measured in the presence of relatively high thermal and hard X-ray background components due to the selective band pass of the crystals combined with direct and indirect X-ray shielding of the detector elements. A five channel system is being commissioned at the National Ignition Facility at Lawrence Livermore National Laboratory for implosion optimization measurements as part of the National Ignition Campaign. Characteristics of the instrument have been measured demonstrating that X-ray bang-time can be measured with {+-} 30ps precision, characterizing the soft X-ray drive to +/- 1eV or 1.5%.

  6. Development of a gated scintillation fiber neutron detector for areal density measurements of inertial confinement fusion capsules

    NASA Astrophysics Data System (ADS)

    Izumi, N.; Lerche, R. A.; Phillips, T. W.; Schmid, G. J.; Moran, M. J.; Koch, J. A.; Azechi, H.; Sangster, T. C.

    2003-03-01

    A detector for fuel areal density measurements in inertial confinement fusion capsules has been designed. Observation of neutrons scattered in an imploded deuterium capsule (0.27-0.6 MeV) is a promising method for areal density measurements in the National Ignition Facility DD surrogate capsules. In order to detect scattered neutrons, we need to (1) suppress interference due to the strong direct neutron burst and (2) suppress the background produced by neutrons scattering on nontarget material (mainly from the target chamber). In our detector system, we suppress direct neutrons by gating the detector. We suppress the nontarget background neutrons by placing the detector outside the target chamber and limiting the view of the detector with collimators. In addition, we are developing a lithium-glass scintillation-fiber detector (LG-SCIFI) to detect the scattered neutrons. The LG-SCIFI will work as a multichannel scintillator array. The scintillation signal will be amplified by a microchannel plate image intensifier, which is gated to accept signals only in a specific time-of-flight window for the scattered neutrons. The gated scintillation image will be recorded by a charge-coupled device. Since the detector is segmented, neutron detection events will be clearly identified as bright spots in the gated image.

  7. Impact of First-Principles Property Calculations of Warm-Dense Deuterium/Tritium on Inertial Confinement Fusion Target Designs

    NASA Astrophysics Data System (ADS)

    Hu, S. X.

    2014-10-01

    Accurate knowledge of the properties of warm dense deuterium/tritium (DT) is essential to reliably design inertial confinement fusion (ICF) implosions. In the warm-dense-matter regime, routinely accessed by low-adiabat ICF implosions, strong-coupling and degeneracy effects play an important role in determining plasma properties. Using first-principles methods of both path-integral Monte Carlo and quantum molecular-dynamics (QMD), we have performed systematic investigation of the equation of state, thermal conductivity, and opacity for DT over a wide range of densities and temperatures. These first-principles properties have been incorporated into our hydrocodes. When compared to hydro simulations using standard plasma models, significant differences in 1-D target performance have been identified for simulations of DT implosions. For low-adiabat (α <= 2) DT plasma conditions, the QMD-predicted opacities are 10 to 100 × higher than predicted by the cold-opacity-patched astrophysical opacity table. The thermal conductivity could be 3 to 10 × larger than the Lee-More model prediction. These enhancements can modify the shell adiabat and shock dynamics in lower- α ICF implosions, which could lead to ~ 40 variations in peak density and neutron yield. This material is based upon work supported by the Department of Energy National Nuclear Security Administration under Award Number DE-NA0001944.

  8. Validating equation of state models in the ablative Richtmyer-Meshkov regime for indirect-drive inertial confinement fusion capsules

    NASA Astrophysics Data System (ADS)

    Loomis, Eric; Braun, Dave; Batha, Steve; Sorce, Charles; Landen, Otto

    2011-10-01

    Recent simulations have shown that isolated features on the outer surface of Inertial Confinement Fusion (ICF) ignition capsules can profoundly impact capsule performance by leading to mixing in the hotspot. Controlling the growth of these artifacts is complicated due to uncertainties in equation of state (EOS) models used in simulation codes. Here we report on measurements pertaining to the growth of isolated defects due to ablative Richtmyer-Meshkov in CH capsules in order to validate these models. Face-on transmission radiography was used to measure the evolution of Gaussian bump arrays in plastic targets. Au halfraums heated to radiation temperatures near 70 eV using 15 beams in a 5 ns pulse from the Omega laser (Laboratory for Laser Energetics, University of Rochester, NY) indirectly drove the samples. Shock speed measurements made with Omega's Active Shock BreakOut (ASBO) diagnostic in conjunction with the x-ray flux recorded by a soft x-ray power diagnostic (DANTE) were used to determine drive conditions in the target. These measurements show that SESAME 7592 is in closer agreement with shock speed and bump growth data compared to LEOS 5310.

  9. Laser absorption, power transfer, and radiation symmetry during the first shock of inertial confinement fusion gas-filled hohlraum experiments

    NASA Astrophysics Data System (ADS)

    Pak, A.; Dewald, E. L.; Landen, O. L.; Milovich, J.; Strozzi, D. J.; Berzak Hopkins, L. F.; Bradley, D. K.; Divol, L.; Ho, D. D.; MacKinnon, A. J.; Meezan, N. B.; Michel, P.; Moody, J. D.; Moore, A. S.; Schneider, M. B.; Town, R. P. J.; Hsing, W. W.; Edwards, M. J.

    2015-12-01

    Temporally resolved measurements of the hohlraum radiation flux asymmetry incident onto a bismuth coated surrogate capsule have been made over the first two nanoseconds of ignition relevant laser pulses. Specifically, we study the P2 asymmetry of the incoming flux as a function of cone fraction, defined as the inner-to-total laser beam power ratio, for a variety of hohlraums with different scales and gas fills. This work was performed to understand the relevance of recent experiments, conducted in new reduced-scale neopentane gas filled hohlraums, to full scale helium filled ignition targets. Experimental measurements, matched by 3D view factor calculations, are used to infer differences in symmetry, relative beam absorption, and cross beam energy transfer (CBET), employing an analytic model. Despite differences in hohlraum dimensions and gas fill, as well as in laser beam pointing and power, we find that laser absorption, CBET, and the cone fraction, at which a symmetric flux is achieved, are similar to within 25% between experiments conducted in the reduced and full scale hohlraums. This work demonstrates a close surrogacy in the dynamics during the first shock between reduced-scale and full scale implosion experiments and is an important step in enabling the increased rate of study for physics associated with inertial confinement fusion.

  10. Simultaneous neutron and x-ray imaging of inertial confinement fusion experiments along a single line of sight at Omega.

    PubMed

    Danly, C R; Day, T H; Fittinghoff, D N; Herrmann, H; Izumi, N; Kim, Y H; Martinez, J I; Merrill, F E; Schmidt, D W; Simpson, R A; Volegov, P L; Wilde, C H

    2015-04-01

    Neutron and x-ray imaging provide critical information about the geometry and hydrodynamics of inertial confinement fusion implosions. However, existing diagnostics at Omega and the National Ignition Facility (NIF) cannot produce images in both neutrons and x-rays along the same line of sight. This leads to difficulty comparing these images, which capture different parts of the plasma geometry, for the asymmetric implosions seen in present experiments. Further, even when opposing port neutron and x-ray images are available, they use different detectors and cannot provide positive information about the relative positions of the neutron and x-ray sources. A technique has been demonstrated on implosions at Omega that can capture x-ray images along the same line of sight as the neutron images. The technique is described, and data from a set of experiments are presented, along with a discussion of techniques for coregistration of the various images. It is concluded that the technique is viable and could provide valuable information if implemented on NIF in the near future. PMID:25933858

  11. Performance of a prototype for a large-aperture multipass Nd:glass laser for inertial confinement fusion

    SciTech Connect

    Van Wonterghem, B.M.; Murray, J.R.; Campbell, J.H.; Speck, D.R.; Barker, C.E.; Smith, I.C.; Browning, D.F.; Behrendt, W.C.

    1997-07-01

    The Beamlet is a single-beam prototype of future multibeam megajoule-class Nd:glass laser drivers for inertial confinement fusion. It uses a multipass main amplifier, adaptive optics, and efficient, high-fluence frequency conversion to the third harmonic. The Beamlet amplifier contains Brewster-angle glass slabs with a clear aperture of 39 cm{times}39 cm and a full-aperture plasma-electrode Pockels cell switch. It has been successfully tested over a range of pulse lengths from 1{endash}10 ns up to energies at 1.053 {mu}m of 5.8 kJ at 1 ns and 17.3 kJ at 10 ns. A 39-actuator deformable mirror corrects the beam quality to a Strehl ratio of as much as 0.4. The 1.053-{mu}m output has been converted to the third harmonic at efficiencies as high as 80{percent} and fluences as high as 8.7 J/cm{sup 2} for 3-ns pulses. {copyright} 1997 Optical Society of America

  12. Measurement of Hydrodynamic Growth near Peak Velocity in an Inertial Confinement Fusion Capsule Implosion using a Self-Radiography Technique.

    PubMed

    Pickworth, L A; Hammel, B A; Smalyuk, V A; MacPhee, A G; Scott, H A; Robey, H F; Landen, O L; Barrios, M A; Regan, S P; Schneider, M B; Hoppe, M; Kohut, T; Holunga, D; Walters, C; Haid, B; Dayton, M

    2016-07-15

    First measurements of hydrodynamic growth near peak implosion velocity in an inertial confinement fusion (ICF) implosion at the National Ignition Facility were obtained using a self-radiographing technique and a preimposed Legendre mode 40, λ=140  μm, sinusoidal perturbation. These are the first measurements of the total growth at the most unstable mode from acceleration Rayleigh-Taylor achieved in any ICF experiment to date, showing growth of the areal density perturbation of ∼7000×. Measurements were made at convergences of ∼5 to ∼10× at both the waist and pole of the capsule, demonstrating simultaneous measurements of the growth factors from both lines of sight. The areal density growth factors are an order of magnitude larger than prior experimental measurements and differed by ∼2× between the waist and the pole, showing asymmetry in the measured growth factors. These new measurements significantly advance our ability to diagnose perturbations detrimental to ICF implosions, uniquely intersecting the change from an accelerating to decelerating shell, with multiple simultaneous angular views. PMID:27472117

  13. Measurement of Hydrodynamic Growth near Peak Velocity in an Inertial Confinement Fusion Capsule Implosion using a Self-Radiography Technique

    NASA Astrophysics Data System (ADS)

    Pickworth, L. A.; Hammel, B. A.; Smalyuk, V. A.; MacPhee, A. G.; Scott, H. A.; Robey, H. F.; Landen, O. L.; Barrios, M. A.; Regan, S. P.; Schneider, M. B.; Hoppe, M.; Kohut, T.; Holunga, D.; Walters, C.; Haid, B.; Dayton, M.

    2016-07-01

    First measurements of hydrodynamic growth near peak implosion velocity in an inertial confinement fusion (ICF) implosion at the National Ignition Facility were obtained using a self-radiographing technique and a preimposed Legendre mode 40, λ =140 μ m , sinusoidal perturbation. These are the first measurements of the total growth at the most unstable mode from acceleration Rayleigh-Taylor achieved in any ICF experiment to date, showing growth of the areal density perturbation of ˜7000 × . Measurements were made at convergences of ˜5 to ˜10 × at both the waist and pole of the capsule, demonstrating simultaneous measurements of the growth factors from both lines of sight. The areal density growth factors are an order of magnitude larger than prior experimental measurements and differed by ˜2 × between the waist and the pole, showing asymmetry in the measured growth factors. These new measurements significantly advance our ability to diagnose perturbations detrimental to ICF implosions, uniquely intersecting the change from an accelerating to decelerating shell, with multiple simultaneous angular views.

  14. Development of backlighting sources for a Compton radiography diagnostic of inertial confinement fusion targets (invited)a)

    NASA Astrophysics Data System (ADS)

    Tommasini, R.; MacPhee, A.; Hey, D.; Ma, T.; Chen, C.; Izumi, N.; Unites, W.; MacKinnon, A.; Hatchett, S. P.; Remington, B. A.; Park, H. S.; Springer, P.; Koch, J. A.; Landen, O. L.; Seely, John; Holland, Glenn; Hudson, Larry

    2008-10-01

    We present scaled demonstrations of backlighter sources, emitting bremsstrahlung x rays with photon energies above 75keV, that we will use to record x-ray Compton radiographic snapshots of cold dense DT fuel in inertial confinement fusion implosions at the National Ignition Facility (NIF). In experiments performed at the Titan laser facility at Lawrence Livermore National Laboratory, we measured the source size and the bremsstrahlung spectrum as a function of laser intensity and pulse length from solid targets irradiated at 2×1017-5×1018W/cm2 using 2-40ps pulses. Using Au planar foils we achieved source sizes down to 5.5μm and conversion efficiencies of about 1×10-13J/J into x-ray photons with energies in the 75-100keV spectral range. We can now use these results to design NIF backlighter targets and shielding and to predict Compton radiography performance as a function of the NIF implosion yield and associated background.

  15. Laser absorption, power transfer, and radiation symmetry during the first shock of inertial confinement fusion gas-filled hohlraum experiments

    SciTech Connect

    Pak, A.; Dewald, E. L.; Landen, O. L.; Milovich, J.; Strozzi, D. J.; Berzak Hopkins, L. F.; Bradley, D. K.; Divol, L.; Ho, D. D.; MacKinnon, A. J.; Meezan, N. B.; Michel, P.; Moody, J. D.; Moore, A. S.; Schneider, M. B.; Town, R. P. J.; Hsing, W. W.; Edwards, M. J.

    2015-12-15

    Temporally resolved measurements of the hohlraum radiation flux asymmetry incident onto a bismuth coated surrogate capsule have been made over the first two nanoseconds of ignition relevant laser pulses. Specifically, we study the P2 asymmetry of the incoming flux as a function of cone fraction, defined as the inner-to-total laser beam power ratio, for a variety of hohlraums with different scales and gas fills. This work was performed to understand the relevance of recent experiments, conducted in new reduced-scale neopentane gas filled hohlraums, to full scale helium filled ignition targets. Experimental measurements, matched by 3D view factor calculations, are used to infer differences in symmetry, relative beam absorption, and cross beam energy transfer (CBET), employing an analytic model. Despite differences in hohlraum dimensions and gas fill, as well as in laser beam pointing and power, we find that laser absorption, CBET, and the cone fraction, at which a symmetric flux is achieved, are similar to within 25% between experiments conducted in the reduced and full scale hohlraums. This work demonstrates a close surrogacy in the dynamics during the first shock between reduced-scale and full scale implosion experiments and is an important step in enabling the increased rate of study for physics associated with inertial confinement fusion.

  16. Measurement of hydrodynamic growth near peak velocity in an inertial confinement fusion capsule implosion using a self-radiography technique

    DOE PAGESBeta

    Pickworth, L. A.; Hammel, B. A.; Smalyuk, V. A.; MacPhee, A. G.; Scott, H. A.; Robey, H. F.; Landen, O. L.; Barrios, M. A.; Regan, S. P.; Schneider, M. B.; et al

    2016-07-11

    First measurements of hydrodynamic growth near peak implosion velocity in an inertial confinement fusion (ICF) implosion at the National Ignition Facility were obtained using a self-radiographing technique and a preimposed Legendre mode 40, λ = 140 μm, sinusoidal perturbation. These are the first measurements of the total growth at the most unstable mode from acceleration Rayleigh-Taylor achieved in any ICF experiment to date, showing growth of the areal density perturbation of ~7000×. Measurements were made at convergences of ~5 to ~10× at both the waist and pole of the capsule, demonstrating simultaneous measurements of the growth factors from both linesmore » of sight. The areal density growth factors are an order of magnitude larger than prior experimental measurements and differed by ~2× between the waist and the pole, showing asymmetry in the measured growth factors. As a result, these new measurements significantly advance our ability to diagnose perturbations detrimental to ICF implosions, uniquely intersecting the change from an accelerating to decelerating shell, with multiple simultaneous angular views.« less

  17. Kinetic simulations of stimulated Raman backscattering and related processes for the shock-ignition approach to inertial confinement fusion

    SciTech Connect

    Riconda, C.; Weber, S.; Tikhonchuk, V. T.; Heron, A.

    2011-09-15

    A detailed description of stimulated Raman backscattering and related processes for the purpose of inertial confinement fusion requires multi-dimensional kinetic simulations of a full speckle in a high-temperature, large-scale, inhomogeneous plasma. In particular for the shock-ignition scheme operating at high laser intensities, kinetic aspects are predominant. High- (I{lambda}{sub o}{sup 2}{approx}5x10{sup 15}W{mu}m{sup 2}/cm{sup 2}) as well as low-intensity (I{lambda}{sub o}{sup 2}{approx}10{sup 15}W{mu}m{sup 2}/cm{sup 2}) cases show the predominance of collisionless, collective processes for the interaction. While the two-plasmon decay instability and the cavitation scenario are hardly affected by intensity variation, inflationary Raman backscattering proves to be very sensitive. Brillouin backscattering evolves on longer time scales and dominates the reflectivities, although it is sensitive to the intensity. Filamentation and self-focusing do occur for all cases but on time scales too long to affect Raman backscattering.

  18. The impact of laser plasma interactions on three-dimensional drive symmetry in inertial confinement fusion implosions

    SciTech Connect

    Peterson, J. L. Michel, P.; Thomas, C. A.; Town, R. P. J.

    2014-07-15

    Achieving symmetric hohlraum radiation drive is an important aspect of indirectly driven inertial confinement fusion experiments. However, when experimentally delivered laser powers deviate from ideal conditions, the resultant radiation field can become asymmetric. Two situations in which this may arise are random uncorrelated fluctuations, in as-delivered laser power and laser beams that do not participate in the implosion (either intentionally or unintentionally). Furthermore, laser plasma interactions in the hohlraum obfuscate the connection between laser powers and radiation drive. To study the effect of these situations on drive symmetry, we develop a simplified model for crossed-beam energy transfer, laser backscatter, and plasma absorption that can be used in conjunction with view factor calculations to expediently translate laser powers into three-dimensional capsule flux symmetries. We find that crossed-beam energy transfer can alter both the statistical properties of uncorrelated laser fluctuations and the impact of missing laser beams on radiation symmetry. A method is proposed to mitigate the effects of missing laser beams.

  19. Inertial confinement fusion reactor cavity analysis: Progress report for the period 1 July 1986 to 30 June 1987

    SciTech Connect

    Peterson, R.R.; MacFarlane, J.J.; Moses, G.A.; El-Afify, M.; Corradini, M.L.

    1987-07-01

    This is a process report for research performed from July 1, 1986 to June 30, 1987, for Lawrence Livermore National Laboratory under subcontract number 9265205 with the project title: Inertial Confinement Fusion Reactor Cavity Analysis. This research generally considers the problems of vaporization and condensation of liquid metal or solid first surface materials in high yield ICF facilities such as reactors or high yield target test experiments. The past year's research consisted of 1.2 man years of effort on three tasks. These tasks were: verify the current vaporization-condensation models in CONRAD through literature surveys of relevant published data, and evaluation and comparison of these data with predictions by CONRAD on condensation phenomena, and with predictions by CONRAD, ZPINCH, and/or MIXERG on radiation phenomena, design a small-scale vaporization experiment by evaluating existing experimental facilities, selecting a primary facility, and conceptually designing an experiment complete with facility parameters and measurables, and design a small-scale condensation experiment including experimental parameters, measurables, and diagnostics. 48 refs.

  20. Abrasion-resistant solgel antireflective films with a high laser-induced damage threshold for inertial confinement fusion

    NASA Astrophysics Data System (ADS)

    Xu, Yao; Zhang, Lei; Wu, Dong; Sun, Yu Han; Huang, Zu Xing; Jiang, Xiao Dong; Wei, Xiao Feng; Li, Zhi Hong; Dong, Bao Zhong; Wu, Zhong Hua

    2005-09-01

    To prepare abrasion-resistant antireflective (AR) films for inertial confinement fusion, four solgel routes have been investigated on polysiloxane-modified and polyvinylalcohol- (PVA-) modified SiO2 sols. As confirmed with a transmissive electron microscope, different fractal structure characteristics of the modified SiO2 particles are disclosed by small-angle x-ray scattering technology. And it is these special fractal characteristics that determine the performance of AR films on the level of internal microstructure. A 29Si magic angle spinning and nuclear magnetic resonance study has been successfully applied in explaining the fractal microstructure and its relation to the laser-induced damage threshold (LIDT) of AR films. The films modified by PVA120000 or acetic acid-catalyzed polysiloxane have higher LIDTs than those films modified by PVA16000 or hydrochloride acid-catalyzed polysiloxane. The films from PVA-modified SiO2 sols have a stronger abrasion resistance but lower antireflection than those films from polysiloxane-modified SiO2 sols. In addition, the films from polysiloxane-modified SiO2 sols can possess high transmittance and high LIDT if the polysiloxane synthesis condition is appropriately chosen, but the abrasion resistance is not as good as that from PVA modification. If strong abrasion resistance is necessary, a possible resolution may be to choose a more appropriate hydrophilic polymer than PVA. If not, polysiloxane-modified silica sol can also work when polysiloxane is synthesized under acetic acid catalysis.

  1. Time evolution of filamentation and self-generated fields in the coronae of directly driven inertial-confinement fusion capsules

    SciTech Connect

    Seguin, F. H.; Li, C. K.; Manuel, M. J.-E.; Rinderknecht, H. G.; Sinenian, N.; Frenje, J. A.; Rygg, J. R.; Hicks, D. G.; Petrasso, R. D.; Delettrez, J.; Betti, R.; Marshall, F. J.; Smalyuk, V. A.

    2012-01-15

    Time-gated radiography with monoenergetic 15-MeV protons, 3-MeV protons, and 4-MeV alpha particles has revealed a rich and complex evolution of electromagnetic field structures in and around imploding, directly driven inertial-confinement fusion (ICF) targets at the OMEGA laser facility. Plastic-shell capsules and solid plastic spheres were imaged during and after irradiation with ICF-relevant laser drive (up to 6 x 10{sup 14} W/cm{sup 2}). Radial filaments appeared while the laser was on; they filled, and were frozen into, the out-flowing corona, persisting until well after the end of the laser drive. Data from specially designed experiments indicate that the filaments were not generated by two-plasmon-decay instabilities or by Rayleigh-Taylor instabilities associated with shell acceleration. Before the onset of visible filamentation, quasi-spherical field structures appeared outside the capsule in the images in a form that suggests outgoing shells of net positive charge. We conjecture that these discrete shells are related to multiple peaks seen previously in the spectra of protons ablated from the targets.

  2. Simultaneous neutron and x-ray imaging of inertial confinement fusion experiments along a single line of sight at Omega

    SciTech Connect

    Danly, C. R.; Day, T. H.; Fittinghoff, D. N.; Herrmann, H.; Izumi, N.; Kim, Y. H.; Martinez, J. I.; Merrill, F. E.; Schmidt, D. W.; Simpson, R. A.; Volegov, P. L.; Wilde, C. H.

    2015-04-16

    Neutron and x-ray imaging provide critical information about the geometry and hydrodynamics of inertial confinement fusion implosions. However, existing diagnostics at Omega and the National Ignition Facility (NIF) cannot produce images in both neutrons and x-rays along the same line of sight. This leads to difficulty comparing these images, which capture different parts of the plasma geometry, for the asymmetric implosions seen in present experiments. Further, even when opposing port neutron and x-ray images are available, they use different detectors and cannot provide positive information about the relative positions of the neutron and x-ray sources. A technique has been demonstrated on implosions at Omega that can capture x-ray images along the same line of sight as the neutron images. Thus, the technique is described, and data from a set of experiments are presented, along with a discussion of techniques for coregistration of the various images. It is concluded that the technique is viable and could provide valuable information if implemented on NIF in the near future.

  3. Simultaneous neutron and x-ray imaging of inertial confinement fusion experiments along a single line of sight at Omega

    NASA Astrophysics Data System (ADS)

    Danly, C. R.; Day, T. H.; Fittinghoff, D. N.; Herrmann, H.; Izumi, N.; Kim, Y. H.; Martinez, J. I.; Merrill, F. E.; Schmidt, D. W.; Simpson, R. A.; Volegov, P. L.; Wilde, C. H.

    2015-04-01

    Neutron and x-ray imaging provide critical information about the geometry and hydrodynamics of inertial confinement fusion implosions. However, existing diagnostics at Omega and the National Ignition Facility (NIF) cannot produce images in both neutrons and x-rays along the same line of sight. This leads to difficulty comparing these images, which capture different parts of the plasma geometry, for the asymmetric implosions seen in present experiments. Further, even when opposing port neutron and x-ray images are available, they use different detectors and cannot provide positive information about the relative positions of the neutron and x-ray sources. A technique has been demonstrated on implosions at Omega that can capture x-ray images along the same line of sight as the neutron images. The technique is described, and data from a set of experiments are presented, along with a discussion of techniques for coregistration of the various images. It is concluded that the technique is viable and could provide valuable information if implemented on NIF in the near future.

  4. New concept for a high-repetition-rate reactor for inertial-confinement fusion

    SciTech Connect

    Monsler, M.J.

    1980-11-01

    A new design concept was developed that has three additional features that are very important in reducing program risk: (1) through a proper choice of the working temperature (400 to 540/sup 0/C) and of the liquid metal (lithium or lead-lithium eutectic alloy), we can select a chamber pressure within the range of 10/sup -1/ to 10/sup -4/ Torr, required for the propagation of either a laser-beam or a heavy-ion-beam driver; (2) presently available ferritic steels can be used for the structural material; and (3) the new concept allows flexibility in irradiaton geometry. Although two-sided irradiation at high f/Nos. seems most attractive from the standpoints of minimizing the number of chamber penetrations and of simplifing the layout of the balance of plant, we must provide for the possibility that target-implosion physics will require a more symmetrical illumination geometry.

  5. Estimates of confinement time and energy gain for plasma liner driven magnetoinertial fusion using an analytic self-similar converging shock model

    SciTech Connect

    Cassibry, J. T.; Cortez, R. J.; Hsu, S. C.; Witherspoon, F. D.

    2009-11-15

    Plasma liner driven magnetoinertial fusion (PLMIF) is a fusion energy concept that utilizes an imploding plasma liner to shock heat and compress a magnetized target plasma to fusion conditions. The fusion burn fraction is linearly proportional to the confinement (or ''dwell'') time of the liner-target system at peak compression, and therefore it is important to estimate the dwell time accurately in order to assess the fusion energy yield and gain. In this work, the dwell time has been estimated using the exact solution to a self-similar converging shock model. The dwell time was found to be determined by the sum of the outgoing shock and rarefaction times through the plasma liner at peak compression, and for chosen PLMIF conditions the dwell time was on the order of 1 {mu}s. In addition, we show that the engineering gain, i.e., the total energy extracted as electricity (from fusion plus expanded liner energy) divided by the electrical energy required to implode the liner, exceeds unity for a wide range of liner thicknesses and specific heat ratios.

  6. Inertial confinement fusion quarterly report: October--December 1995. Volume 6, Number 1

    SciTech Connect

    McEachern, R.L.; Carpenter, J.; Miguel, A.; Murphy, P.; Perez, J.; Schleich, D.

    1996-07-01

    This issue presents recent results from the ICF program at Lawrence Livermore National Laboratory in areas ranging from cryogenics to plasma instabilities. The article ``Metastable Crystal Structures of Solid Hydrogen`` describes primarily Raman spectroscopy studies of H{sub 2} and D{sub 2} films deposited at various rates and temperatures. All ignition target designs for ICF require a cryogenic deuterium-tritium (DT) fuel layer of uniform thickness and acceptable roughness. Solid DT layers, in particular, are easier to support in the presence of gravity and self-symmetrize due to self heating from the beta decay of tritium. The roughness of these films is closely related to their crystal structure, so it is important to understand film morphology under different deposition conditions. Three articles present different approaches to the study of plasma instabilities that lead to stimulated Brillouin scattering (SBS) and stimulated Raman scattering (SRS). In ``Modeling of Self-Focusing Experiments by Beam Propagation Codes,`` the authors describe the use of computer codes to model nonlinear effects during the propagation of laser beams through optical elements. Such codes have played a key role in the design of high-power lasers for ICF, both historically and for the NIF. The article ``Optical Scatter--A Diagnostic Tool to Investigate Laser Damage in KDP and DKDP`` examines the important problem of characterizing single crystals of KH{sub 2}PO{sub 4} (KDP) and deuterated KDP. These materials are used as optical switches, for frequency conversion in the Nova laser, and will be required for the NIF. The use of soft x-rays as a plasma probe is the topic of ``Soft X-Ray Interferometry.`` Interferometry of laser-produced plasmas presents a significant challenge, especially at electron densities exceeding 10{sup 20} cm{sup {minus}3}. The authors compare x-ray and optical interferometry of plasmas and show experimental results from a soft x-ray Mach-Zehnder interferometer.

  7. Neutronic Analysis of the Laser Inertial Confinement Fusion-Fission Energy (LIFE) Engine Using Various Thorium Molten Salts

    NASA Astrophysics Data System (ADS)

    Acır, Adem

    2013-08-01

    In this study, a neutronic performance of the Laser Inertial Confinement Fusion Fission Energy (LIFE) molten salt blanket is investigated. Neutronic calculations are performed by using XSDRNPM/SCALE5 codes in S8-P3 approximation. The thorium molten salt composition considered in this calculation is 75 % LiF—25 % ThF4, 75 % LiF—24 % ThF4—1 % 233UF4, 75 % LiF—23 % ThF4—2 % 233UF4. Also, effects of the 6Li enrichment in molten salt are performed for all heavy metal salt. The radiation damage behaviors of SS-304 structural material with respect to higher fissionable fuel content and 6Li enrichment are computed. By higher fissionable fuel content in molten salt and with 6Li enrichment (20 and 50 %) in the coolant in form of 75 % LiF—23 % ThF4—2 % 233UF4, an initial TBR >1.05 can be realized. On the other hand, the 75 % LiF—25 % ThF4 or 75 % LiF—24 % ThF4—1 % 233UF4 molten salt fuel as regards maintained tritium self-sufficiency is not suitable as regards improving neutronic performance of LIFE engine. A high quality fissile fuel with a rate of ~2,850 kg/year of 233U can be produced with 75 % LiF—23 % ThF4—2 % 233UF4. The energy multiplication factor is increased with high rate fission reactions of 233U occurring in the molten salt zone. Major damage mechanisms in SS-304 first wall stell have been computed as DPA = 48 and He = 132 appm per year with 75 % LiF—23 % ThF4—2 % 233UF4. This implies a replacement of the SS-304 first wall stell of every between 3 and 4 years.

  8. Exponential yield sensitivity to long-wavelength asymmetries in three-dimensional simulations of inertial confinement fusion capsule implosions

    SciTech Connect

    Haines, Brian M.

    2015-08-15

    In this paper, we perform a series of high-resolution 3D simulations of an OMEGA-type inertial confinement fusion (ICF) capsule implosion with varying levels of initial long-wavelength asymmetries in order to establish the physical energy loss mechanism for observed yield degradation due to long-wavelength asymmetries in symcap (gas-filled capsule) implosions. These simulations demonstrate that, as the magnitude of the initial asymmetries is increased, shell kinetic energy is increasingly retained in the shell instead of being converted to fuel internal energy. This is caused by the displacement of fuel mass away from and shell material into the center of the implosion due to complex vortical flows seeded by the long-wavelength asymmetries. These flows are not fully turbulent, but demonstrate mode coupling through non-linear instability development during shell stagnation and late-time shock interactions with the shell interface. We quantify this effect by defining a separation lengthscale between the fuel mass and internal energy and show that this is correlated with yield degradation. The yield degradation shows an exponential sensitivity to the RMS magnitude of the long-wavelength asymmetries. This strong dependence may explain the lack of repeatability frequently observed in OMEGA ICF experiments. In contrast to previously reported mechanisms for yield degradation due to turbulent instability growth, yield degradation is not correlated with mixing between shell and fuel material. Indeed, an integrated measure of mixing decreases with increasing initial asymmetry magnitude due to delayed shock interactions caused by growth of the long-wavelength asymmetries without a corresponding delay in disassembly.

  9. Abrasion-resistant solgel antireflective films with a high laser-induced damage threshold for inertial confinement fusion

    SciTech Connect

    Xu Yao; Zhang Lei; Wu Dong; Sun Yu Han; Huang Zuxing; Jiang Xiaodong; Wei Xiaofeng; Li Zhihong; Dong Baozhong; Wu Zhonghua

    2005-09-01

    To prepare abrasion-resistant antireflective (AR) films for inertial confinement fusion, four solgel routes have been investigated on polysiloxane-modified and polyvinylalcohol- (PVA-) modified SiO{sub 2} sols. As confirmed with a transmissive electron microscope, different fractal structure characteristics of the modified SiO{sub 2} particles are disclosed by small-angle x-ray scattering technology. And it is these special fractal characteristics that determine the performance of AR films on the level of internal microstructure. A {sup 29}Si magic angle spinning and nuclear magnetic resonance study has been successfully applied in explaining the fractal microstructure and its relation to the laser-induced damage threshold (LIDT) of AR films. The films modified by PVA120000 or acetic acid-catalyzed polysiloxane have higher LIDTs than those films modified by PVA16000 or hydrochloride acid-catalyzed polysiloxane. The films from PVA-modified SiO{sub 2} sols have a stronger abrasion resistance but lower antireflection than those films from polysiloxane-modified SiO{sub 2} sols. In addition, the films from polysiloxane-modified SiO{sub 2} sols can possess high transmittance and high LIDT if the polysiloxane synthesis condition is appropriately chosen, but the abrasion resistance is not as good as that from PVA modification. If strong abrasion resistance is necessary, a possible resolution may be to choose a more appropriate hydrophilic polymer than PVA. If not, polysiloxane-modified silica sol can also work when polysiloxane is synthesized under acetic acid catalysis.

  10. The design and simulation of high-voltage Applied-B ion diodes for inertial confinement fusion

    NASA Astrophysics Data System (ADS)

    Slutz, S. A.; Seidel, D. B.; Coats, R. S.

    1987-06-01

    We present the design of the high-voltage (30 MV) Applied-B ion diode that is now being tested on the PBFA-II accelerator at Sandia National Laboratories. This diode design is the first application of a new set of numerical design tools that have been developed over the past several years. Furthermore, this design represents significant departures from previous designs due to much higher voltage and the use of a nonprotonic ion, Li+. The higher voltage increases the magnetic field strength required to insulate the diode from 1 to 2 T of previous diodes to 3-7 T. This represents a very large increase in the magnetic field energy and the magnetic forces exerted on the field-coil structures. Our new design incorporates changes in the field-coil locations to significantly reduce the field energy and the forces on the field-coil structures. The use of nonprotonic ions introduces a new complication in that these ions will be stripped when they penetrate material, i.e., the gas cell membrane. The importance of current neutralization, charge-exchange reactions, and the conservation of canonical angular momentum are discussed in the context of designing light ion diodes suitable as drivers for inertial confinement fusion. We have simulated the performance of this diode design using the electromagnetic particle-in-cell code, magic. We find that the most sensitive point in the power flow is the transition from the self-magnetically insulated transmission line to the applied field region of the diode.

  11. Three-dimensional simulation strategy to determine the effects of turbulent mixing on inertial-confinement-fusion capsule performance.

    PubMed

    Haines, Brian M; Grinstein, Fernando F; Fincke, James R

    2014-05-01

    In this paper, we present and justify an effective strategy for performing three-dimensional (3D) inertial-confinement-fusion (ICF) capsule simulations. We have evaluated a frequently used strategy in which two-dimensional (2D) simulations are rotated to 3D once sufficient relevant 2D flow physics has been captured and fine resolution requirements can be restricted to relatively small regions. This addresses situations typical of ICF capsules which are otherwise prohibitively intensive computationally. We tested this approach for our previously reported fully 3D simulations of laser-driven reshock experiments where we can use the available 3D data as reference. Our studies indicate that simulations that begin as purely 2D lead to significant underprediction of mixing and turbulent kinetic energy production at later time when compared to the fully 3D simulations. If, however, additional suitable nonuniform perturbations are applied at the time of rotation to 3D, we show that one can obtain good agreement with the purely 3D simulation data, as measured by vorticity distributions as well as integrated mixing and turbulent kinetic energy measurements. Next, we present results of simulations of a simple OMEGA-type ICF capsule using the developed strategy. These simulations are in good agreement with available experimental data and suggest that the dominant mechanism for yield degradation in ICF implosions is hydrodynamic instability growth seeded by long-wavelength surface defects. This effect is compounded by drive asymmetries and amplified by repeated shock interactions with an increasingly distorted shell, which results in further yield reduction. Our simulations are performed with and without drive asymmetries in order to compare the importance of these effects to those of surface defects; our simulations indicate that long-wavelength surface defects degrade yield by approximately 60% and short-wavelength drive asymmetry degrades yield by a further 30%. PMID

  12. Perspectives for the high field approach in fusion research and advances within the Ignitor Program

    NASA Astrophysics Data System (ADS)

    Coppi, B.; Airoldi, A.; Albanese, R.; Ambrosino, G.; Belforte, G.; Boggio-Sella, E.; Cardinali, A.; Cenacchi, G.; Conti, F.; Costa, E.; D'Amico, A.; Detragiache, P.; De Tommasi, G.; DeVellis, A.; Faelli, G.; Ferraris, P.; Frattolillo, A.; Giammanco, F.; Grasso, G.; Lazzaretti, M.; Mantovani, S.; Merriman, L.; Migliori, S.; Napoli, R.; Perona, A.; Pierattini, S.; Pironti, A.; Ramogida, G.; Rubinacci, G.; Sassi, M.; Sestero, A.; Spillantini, S.; Tavani, M.; Tumino, A.; Villone, F.; Zucchi, L.

    2015-05-01

    The Ignitor Program maintains the objective of approaching D-T ignition conditions by incorporating systematical advances made with relevant high field magnet technology and with experiments on high density well confined plasmas in the present machine design. An additional objective is that of charting the development of the high field line of experiments that goes from the Alcator machine to the ignitor device. The rationale for this class of experiments, aimed at producing poloidal fields with the highest possible values (compatible with proven safety factors of known plasma instabilities) is given. On the basis of the favourable properties of high density plasmas produced systematically by this line of machines, the envisioned future for the line, based on novel high field superconducting magnets, includes the possibility of investigating more advanced fusion burn conditions than those of the D-T plasmas for which Ignitor is designed. Considering that a detailed machine design has been carried out (Coppi et al 2013 Nucl. Fusion 53 104013), the advances made in different areas of the physics and technology that are relevant to the Ignitor project are reported. These are included within the following sections of the present paper: main components issues, assembly and welding procedures; robotics criteria; non-linear feedback control; simulations with three-dimensional structures and disruption studies; ICRH and dedicated diagnostics systems; anomalous transport processes including self-organization for fusion burning regimes and the zero-dimensional model; tridimensional structures of the thermonuclear instability and control provisions; superconducting components of the present machine; envisioned experiments with high field superconducting magnets.

  13. Behavioral and biological interactions with confined microsocieties in a programmed environment

    NASA Technical Reports Server (NTRS)

    Emurian, H. H.; Brady, J. V.; Meyerhoff, J. L.; Mougey, E. H.

    1981-01-01

    This paper presents a summary of the background, objectives, and methodological approach of an ongoing research project devoted to the analysis of individual and small group performance effectiveness under conditions of isolation and confinement during extended residences in a continuously programmed environment. A more detailed description is provided of the results of a recent series of experiments designed and conducted to assess hormonal and behavioral effects of a change in group membership and size.

  14. Heavy Ion Inertial Fusion Energy: Summaries of Program Elements

    SciTech Connect

    Friedman, A; Barnard, J J; Kaganovich, I; Seidl, P A; Briggs, R J; Faltens, A; Kwan, J W; Lee, E P; Logan, B G

    2011-02-28

    The goal of the Heavy Ion Fusion (HIF) Program is to apply high-current accelerator technology to IFE power production. Ion beams of mass {approx}100 amu and kinetic energy {>=} 1 GeV provide efficient energy coupling into matter, and HIF enjoys R&D-supported favorable attributes of: (1) the driver, projected to be robust and efficient; see 'Heavy Ion Accelerator Drivers.'; (2) the targets, which span a continuum from full direct to full indirect drive (and perhaps fast ignition), and have metal exteriors that enable injection at {approx}10 Hz; see 'IFE Target Designs'; (3) the near-classical ion energy deposition in the targets; see 'Beam-Plasma Interactions'; (4) the magnetic final lens, robust against damage; see 'Final Optics-Heavy Ion Beams'; and (5) the fusion chamber, which may use neutronically-thick liquids; see 'Liquid-Wall Chambers.' Most studies of HIF power plants have assumed indirect drive and thick liquid wall protection, but other options are possible.

  15. Fusion Power Program biannual progress report, April-September 1979

    SciTech Connect

    Not Available

    1980-02-01

    This biannual report summarizes the Argonne National Laboratory work performed for the Office of Fusion Energy during the April-September 1979 quarter in the following research and development areas: materials; energy storage and transfer; tritium containment, recovery and control; advanced reactor design; atomic data; reactor safety; fusion-fission hybrid systems; alternate applications of fusion energy; and other work related to fusion power. Separate abstracts were prepared for three sections. (MOW)

  16. Fusion

    NASA Astrophysics Data System (ADS)

    Herman, Robin

    1990-10-01

    The book abounds with fascinating anecdotes about fusion's rocky path: the spurious claim by Argentine dictator Juan Peron in 1951 that his country had built a working fusion reactor, the rush by the United States to drop secrecy and publicize its fusion work as a propaganda offensive after the Russian success with Sputnik; the fortune Penthouse magazine publisher Bob Guccione sank into an unconventional fusion device, the skepticism that met an assertion by two University of Utah chemists in 1989 that they had created "cold fusion" in a bottle. Aimed at a general audience, the book describes the scientific basis of controlled fusion--the fusing of atomic nuclei, under conditions hotter than the sun, to release energy. Using personal recollections of scientists involved, it traces the history of this little-known international race that began during the Cold War in secret laboratories in the United States, Great Britain and the Soviet Union, and evolved into an astonishingly open collaboration between East and West.

  17. Fusion programs in applied plasma physics. Final report, fiscal years 1989--1991

    SciTech Connect

    Not Available

    1992-02-01

    The objectives of the theoretical science program are: To support the interpretation of present experiments and predict the outcome of future planned experiments; to improve on existing models and codes and validate against experimental results; and to conduct theoretical physics development of advanced concepts with applications for DIII-D and future devices. Major accomplishments in FY91 include the corroboration between theory and experiment on MHD behavior in the second stable regime of operation on DIII-D, and the frequency and mode structure of toroidal Alfven eigenmodes in high beta, shaped plasmas. We have made significant advances in the development of the gyro-Landau fluid approach to turbulence simulation which more accurately models kinetic drive and damping mechanisms. Several theoretical models to explain the bifurcation phenomenon in L- to H-mode transition were proposed providing the theoretical basis for future experimental verification. The capabilities of new rf codes have been upgraded in response to the expanding needs of the rf experiments. Codes are being employed to plan for a fully non-inductive current drive experiment in a high beta, enhanced confinement regime. GA`s experimental effort in Applied Physics encompasses two advanced diagnostics essential for the operation of future fusion experiments: Alpha particle diagnostic, and current and density profile diagnostics. This paper discusses research in all these topics.

  18. Status of Safety and Environmental Activities in the US Fusion Program

    SciTech Connect

    David A. Petti; Susana Reyes; Lee C. Cadwallader; Jeffery F. Latkowski

    2004-09-01

    This paper presents an overview of recent safety efforts in both magnetic and inertial fusion energy. Safety has been a part of fusion design and operations since the inception of fusion research. Safety research and safety design support have been provided for a variety of experiments in both the magnetic and inertial fusion programs. The main safety issues are reviewed, some recent safety highlights are discussed and the programmatic impacts that safety research has had are presented. Future directions in the safety and environmental area are proposed.

  19. Status of Safety and Environmental Activities in the US Fusion Program

    SciTech Connect

    Petti, D A; Reyes, S; Cadwallader, L C; Latkowski, J F

    2004-09-02

    This paper presents an overview of recent safety efforts in both magnetic and inertial fusion energy. Safety has been a part of fusion design and operations since the inception of fusion research. Safety research and safety design support have been provided for a variety of experiments in both the magnetic and inertial fusion programs. The main safety issues are reviewed, some recent safety highlights are discussed and the programmatic impacts that safety research has had are presented. Future directions in the safety and environmental area are proposed.

  20. Inertial electrostatic confinement and nuclear fusion in the interelectrode plasma of a nanosecond vacuum discharge. II: Particle-in-cell simulations

    NASA Astrophysics Data System (ADS)

    Kurilenkov, Yu. K.; Tarakanov, V. P.; Gus'kov, S. Yu.

    2010-12-01

    Results of particle-in-sell simulations of ion acceleration by using the KARAT code in a cylindrical geometry in the problem formulation corresponding to an actual experiment with a low-energy vacuum discharge with a hollow cathode are presented. The fundamental role of the formed virtual cathode is analyzed. The space-time dynamics of potential wells related to the formation of the virtual cathode is discussed. Quasi-steady potential wells (with a depth of ˜80% of the applied voltage) cause acceleration of deuterium ions to energies about the electron beam energy (˜50 keV). In the well, a quasi-isotropic velocity distribution function of fast ions forms. The results obtained are compared with available data on inertial electrostatic confinement fusion (IECF). In particular, similar correlations between the structure of potential wells and the neutron yield, as well as the scaling of the fusion power density, which increases with decreasing virtual cathode radius and increasing potential well depth, are considered. The chosen electrode configuration and potential well parameters provide power densities of nuclear DD fusion in a nanosecond vacuum discharge noticeably higher than those achieved in other similar IECF systems.