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O. S. Jones

Bio: O. S. Jones is an academic researcher from Lawrence Livermore National Laboratory. The author has contributed to research in topics: National Ignition Facility & Hohlraum. The author has an hindex of 49, co-authored 176 publications receiving 7703 citations.


Papers
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Journal ArticleDOI
TL;DR: In this paper, Marinak et al. used the HYDRA multiphysics radiation hydrodynamics code to simulate a cylindrical NIF hohlraum that includes an imploding capsule.
Abstract: The performance of a targets designed for the National Ignition Facility (NIF) are simulated in three dimensions using the HYDRA multiphysics radiation hydrodynamics code. [M. Marinak et al., Phys. Plasmas 5, 1125 (1998)] In simulations of a cylindrical NIF hohlraum that include an imploding capsule, all relevant hohlraum features and the detailed laser illumination pattern, the motion of the wall material inside the hohlraum shows a high degree of axisymmetry. Laser light is able to propagate through the entrance hole for the required duration of the pulse. Gross hohlraum energetics mirror the results from an axisymmetric simulation. A NIF capsule simulation resolved the full spectrum of the most dangerous modes that grow from surface roughness. Hydrodynamic instabilities evolve into the weakly nonlinear regime. There is no evidence of anomalous low mode growth driven by nonlinear mode coupling.

615 citations

Journal ArticleDOI
TL;DR: Miller et al. as discussed by the authors proposed a point design for the initial ignition campaign on the National Ignition Facility (NIF) using D-T fusion fuel in an ablator of either CH with Ge doping, or Be with Cu.
Abstract: Point design targets have been specified for the initial ignition campaign on the National Ignition Facility [G. H. Miller, E. I. Moses, and C. R. Wuest, Opt. Eng. 443, 2841 (2004)]. The targets contain D-T fusion fuel in an ablator of either CH with Ge doping, or Be with Cu. These shells are imploded in a U or Au hohlraum with a peak radiation temperature set between 270 and 300 eV. Considerations determining the point design include laser-plasma interactions, hydrodynamic instabilities, laser operations, and target fabrication. Simulations were used to evaluate choices, and to define requirements and specifications. Simulation techniques and their experimental validation are summarized. Simulations were used to estimate the sensitivity of target performance to uncertainties and variations in experimental conditions. A formalism is described that evaluates margin for ignition, summarized in a parameter the Ignition Threshold Factor (ITF). Uncertainty and shot-to-shot variability in ITF are evaluated, and...

534 citations

Journal ArticleDOI
M. J. Edwards1, P. K. Patel, J. D. Lindl1, L. J. Atherton, Siegfried Glenzer, S. W. Haan, J. D. Kilkenny, O. L. Landen, Edward I. Moses, A. Nikroo, R. D. Petrasso, T. C. Sangster, P. T. Springer, Steven H. Batha, R. Benedetti, L. A. Bernstein, Riccardo Betti, D. L. Bleuel, T. R. Boehly, D. K. Bradley, J. A. Caggiano, D. A. Callahan, P. M. Celliers, C. J. Cerjan, K. C. Chen, Daniel Clark, Gilbert Collins, E. L. Dewald, Laurent Divol, S. N. Dixit, Tilo Doeppner, D. H. Edgell, James E. Fair, Michael Farrell, R. J. Fortner, Johan Frenje, M. Gatu Johnson, E. M. Giraldez, V. Yu. Glebov, Gary Grim, B. A. Hammel, A. V. Hamza, D. R. Harding, S. P. Hatchett, N. Hein, Hans W. Herrmann, Damien Hicks, D. E. Hinkel, M. Hoppe, W. W. Hsing, Nobuhiko Izumi, B. Jacoby, O. S. Jones, Daniel H. Kalantar, Robert L. Kauffman, John Kline, J. P. Knauer, J. A. Koch, B. J. Kozioziemski, G. A. Kyrala, K. N. LaFortune, S. Le Pape, R. J. Leeper, R. A. Lerche, T. Ma, B. J. MacGowan, A. J. Mackinnon, Andrew MacPhee, Evan Mapoles, M. M. Marinak, M. Mauldin, P. W. McKenty, M. Meezan, Pierre Michel, Jose Milovich, J. D. Moody, Matthew Moran, D. H. Munro, C. L. Olson, Kathy Opachich, Art Pak, T. G. Parham, H.-S. Park, Joseph Ralph, Sean Regan, Bruce Remington, H. G. Rinderknecht, Harry Robey, M. D. Rosen, Steven Ross, Jay D. Salmonson, J. D. Sater, D. H. Schneider, Fredrick Seguin, Scott Sepke, D. A. Shaughnessy, V. A. Smalyuk, Brian Spears, Christian Stoeckl, Wolfgang Stoeffl, L. J. Suter, Cliff Thomas, R. Tommasini, Richard Town, S. V. Weber, Paul J. Wegner, K. Widman, Mark D. Wilke, Doug Wilson, Charles Yeamans, Alex Zylstra 
TL;DR: In this paper, a low-Z capsule filled with deuterium-tritium (DT) fuel via laser indirect-drive inertial confinement fusion and demonstrate fusion ignition and propagating thermonuclear burn with a net energy gain of ∼5-10 (fusion yield/input laser energy).
Abstract: The National Ignition Facility (NIF) at Lawrence Livermore National Laboratory includes a precision laser system now capable of delivering 1.8 MJ at 500 TW of 0.35-μm light to a target. NIF has been operational since March 2009. A variety of experiments have been completed in support of NIF's mission areas: national security, fundamental science, and inertial fusion energy. NIF capabilities and infrastructure are in place to support its missions with nearly 60 X-ray, optical, and nuclear diagnostic systems. A primary goal of the National Ignition Campaign (NIC) on the NIF was to implode a low-Z capsule filled with ∼0.2 mg of deuterium-tritium (DT) fuel via laser indirect-drive inertial confinement fusion and demonstrate fusion ignition and propagating thermonuclear burn with a net energy gain of ∼5–10 (fusion yield/input laser energy). This requires assembling the DT fuel into a dense shell of ∼1000 g/cm3 with an areal density (ρR) of ∼1.5 g/cm2, surrounding a lower density hot spot with a temperature of ∼10 keV and a ρR ∼0.3 g/cm2, or approximately an α-particle range. Achieving these conditions demand precise control of laser and target parameters to allow a low adiabat, high convergence implosion with low ablator fuel mix. We have demonstrated implosion and compressed fuel conditions at ∼80–90% for most point design values independently, but not at the same time. The nuclear yield is a factor of ∼3–10× below the simulated values and a similar factor below the alpha dominated regime. This paper will discuss the experimental trends, the possible causes of the degraded performance (the off-set from the simulations), and the plan to understand and resolve the underlying physics issues.

271 citations

Journal ArticleDOI
TL;DR: The comparison with radiation-hydrodynamic modeling indicates that low mode asymmetries and increased ablator surface perturbations may be responsible for the current performance of deuterium-tritium inertial confinement fusion implosion experiments.
Abstract: Deuterium-tritium inertial confinement fusion implosion experiments on the National Ignition Facility have demonstrated yields ranging from 0.8 to $7\ifmmode\times\else\texttimes\fi{}{10}^{14}$, and record fuel areal densities of 0.7 to $1.3\text{ }\text{ }\mathrm{g}/{\mathrm{cm}}^{2}$. 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.

215 citations


Cited by
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Journal ArticleDOI
TL;DR: The 1990 National Academy of Science final report of its review of the Inertial Confinement Fusion Program recommended completion of a series of target physics objectives on the 10-beam Nova laser at the Lawrence Livermore National Laboratory as the highest priority prerequisite for proceeding with construction of an ignition-scale laser facility as mentioned in this paper.
Abstract: The 1990 National Academy of Science final report of its review of the Inertial Confinement Fusion Program recommended completion of a series of target physics objectives on the 10-beam Nova laser at the Lawrence Livermore National Laboratory as the highest-priority prerequisite for proceeding with construction of an ignition-scale laser facility, now called the National Ignition Facility (NIF). These objectives were chosen to demonstrate that there was sufficient understanding of the physics of ignition targets that the laser requirements for laboratory ignition could be accurately specified. This research on Nova, as well as additional research on the Omega laser at the University of Rochester, is the subject of this review. The objectives of the U.S. indirect-drive target physics program have been to experimentally demonstrate and predictively model hohlraum characteristics, as well as capsule performance in targets that have been scaled in key physics variables from NIF targets. To address the hohlrau...

1,601 citations

Book
19 Dec 2003
TL;DR: In this article, the Equations of Gas Dynamics and Magnetoplasmas Dynamics were studied, as well as Magnetoplasma Stability and Transport in Magnetplasmas and Magnetic Stability.
Abstract: 1 The Equations of Gas Dynamics 2 Magnetoplasma Dynamics 3 Waves in Magnetoplasmas 4 Magnetoplasma Stability 5 Transport in Magnetoplasmas 6 Extensions of Theory Bibliography Index

748 citations

Journal ArticleDOI
20 Feb 2014-Nature
TL;DR: In this article, the authors 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.
Abstract: 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.

733 citations

Journal ArticleDOI
TL;DR: In this article, the authors developed accurate x-ray scattering techniques to measure the physical properties of dense plasmas for applications in high energy density physics, including inertial confinement fusion, material science, or laboratory astrophysics.
Abstract: Accurate x-ray scattering techniques to measure the physical properties of dense plasmas have been developed for applications in high energy density physics. This class of experiments produces short-lived hot dense states of matter with electron densities in the range of solid density and higher where powerful penetrating x-ray sources have become available for probing. Experiments have employed laser-based x-ray sources that provide sufficient photon numbers in narrow bandwidth spectral lines, allowing spectrally resolved x-ray scattering measurements from these plasmas. The backscattering spectrum accesses the noncollective Compton scattering regime which provides accurate diagnostic information on the temperature, density, and ionization state. The forward scattering spectrum has been shown to measure the collective plasmon oscillations. Besides extracting the standard plasma parameters, density and temperature, forward scattering yields new observables such as a direct measure of collisions and quantum effects. Dense matter theory relates scattering spectra with the dielectric function and structure factors that determine the physical properties of matter. Applications to radiation-heated and shock-compressed matter have demonstrated accurate measurements of compression and heating with up to picosecond temporal resolution. The ongoing development of suitable x-ray sources and facilities will enable experiments in a wide range of research areas including inertial confinement fusion,more » radiation hydrodynamics, material science, or laboratory astrophysics.« less

612 citations

Journal ArticleDOI
TL;DR: In this article, Zhou et al. presented the initial condition dependence of Rayleigh-Taylor (RT) and Richtmyer-Meshkov (RM) mixing layers, and introduced parameters that are used to evaluate the level of mixedness and mixed mass within the layers.

606 citations