A5068395010- Laser-Plasma Interactions and Diagnostics
- Laser-induced spectroscopy and plasma
- Atomic and Molecular Physics
- Laser Design and Applications
- Combustion and Detonation Processes
- Magnetic confinement fusion research
- Energetic Materials and Combustion
- High-pressure geophysics and materials
- Nuclear Physics and Applications
- Laser-Matter Interactions and Applications
- Nuclear reactor physics and engineering
- Cold Fusion and Nuclear Reactions
- Gas Dynamics and Kinetic Theory
- Fusion materials and technologies
- Ionosphere and magnetosphere dynamics
- Ocular and Laser Science Research
- Pulsed Power Technology Applications
- Computational Fluid Dynamics and Aerodynamics
- Rocket and propulsion systems research
- Astro and Planetary Science
- Laser Material Processing Techniques
- Plasma Diagnostics and Applications
- Electron and X-Ray Spectroscopy Techniques
- Solar and Space Plasma Dynamics
- Fluid Dynamics and Turbulent Flows
Lawrence Livermore National Laboratory
2014-2024
General Atomics (United States)
2014
CEA DAM Île-de-France
2014
Massachusetts Institute of Technology
2014
Fusion Academy
2014
Fusion (United States)
2014
Los Alamos National Laboratory
2014
Rutherford Appleton Laboratory
2014
Sandia National Laboratories
2014
Bellevue Hospital Center
2009-2010
The quotidian equation of state (QEOS) is a general-purpose model for use in hydrodynamic simulation high-pressure phenomena. Electronic properties are obtained from modified Thomas–Fermi statistical model, while ion thermal motion described by multiphase combining Debye, Grüneisen, Lindemann, and fluid-scaling laws. theory gives smooth usable predictions ionization state, pressure, energy, entropy, Helmholtz free energy. When necessary, the results may be temperature-dependent pressure...
view Abstract Citations (659) References (56) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS Presupernova evolution of massive stars. Weaver, T. A. ; Zimmerman, G. B. Woosley, S. E. Results are reported for detailed calculations the complete 15- and 25-solar-mass Population I stars from ZAMS to iron core collapse. The structure entire is computed using an implicit hydrodynamics computer code, careful consideration given complex nuclear processes that...
As fusion experiments at the National Ignition Facility (NIF) approach and exceed breakeven, energy from burning capsule is predicted to couple gold walls reheat hohlraum. On December 5, 2022, experiment N221204 exceeded target historically achieving 3.15 MJ of 2.05 laser drive; for first time, igniting reheated hohlraum beyond peak laser-driven radiation temperature 313 eV a 350 eV, in less than half nanosecond. This reheating effect has now been unambiguously observed by two independent...
Several targets are described that in simulations give yields of 1–30 MJ when indirectly driven by 0.9–2 0.35 μm laser light. The article describes the targets, modeling was used to design them, and done set specifications for system proposed National Ignition Facility. Capsules with beryllium or polystyrene ablators enclosed gold hohlraums. All designs utilize a cryogenic fuel layer; it is very difficult achieve ignition at this scale noncryogenic capsule. It necessary use multiple bands...
A high Mach number, radiatively cooled jet of astrophysical interest has been produced using intense laser irradiation a gold cone. The evolution the was imaged in emission and radiography, temperature measured with Thomson scattering. Comparison numerical simulations shows that radiative cooling is dominant mechanism collapse Au plasma on axis, temperatures plummeting peak densities increasing, each by an order magnitude $\ensuremath{\sim}\frac{1}{2}\mathrm{ns}$. In dimensionless terms,...
Calculations are presented for a high yield inertial fusion design, employing indirect drive with double-ended z-pinch-driven hohlraum radiation source. A current (∼60 MA) accelerator implodes z pinches within an enclosing hohlraum. Radial spoke arrays and shine shields isolate the capsule from pinch plasma, magnetic field, direct x-ray shine. Our approach places minimal requirements on z-pinch uniformity stability, usually problematic due to magneto-Rayleigh–Taylor instability. Large...
We present the first simultaneous observations of ion acoustic and electron plasma waves in laser-produced dense plasmas with Thomson scattering. In addition to measuring standard parameters, temperature density, this novel experimental technique is shown be a sensitive method for temporally spatially resolved measurements averaged ionization stage plasma. Experiments highly ionized gold clearly show that inclusion dielectronic recombination radiation-hydrodynamic modeling critically...
We report for the first time on full 2-D radiation-hydrodynamic implosion simulations that explore impact of highly compressed imposed magnetic fields ignition and burn perturbed spherical implosions ignition-scale cryogenic capsules. Using perturbations convolute cold fuel boundary hotspot prevent without applied fields, we impose initial axial seed 20–100 T (potentially attainable using present experimental methods) compress to greater than 4 × 104 (400 MG) under implosion, thereby...
A series of 40 experiments on the National Ignition Facility (NIF) [E. I. Moses et al., Phys. Plasmas 16, 041006 (2009)] to study energy balance and implosion symmetry in reduced- full-scale ignition hohlraums was shot at energies up 1.3 MJ. This paper reports findings analysis ensemble experimental data obtained that has produced an improved model for simulating hohlraums. Last year first observation a NIF hohlraum transfer between cones beams as function wavelength shift those reported [P....
We examine the potential that imposed magnetic fields of tens Tesla increase to greater than 10 kT (100 MGauss) under implosion compression may relax conditions required for ignition and propagating burn in indirect-drive inertial confinement fusion (ICF) targets. This allow attainment ignition, or at least significant energy yields, presently performing ICF targets on National Ignition Facility (NIF) today are sub-marginal thermonuclear through adverse hydrodynamic stagnation [Doeppner et...
The application of an external 26 Tesla axial magnetic field to a D2 gas-filled capsule indirectly driven on the National Ignition Facility is observed increase ion temperature by 40% and neutron yield factor 3.2 in hot spot with areal density approaching what required for fusion ignition [1]. improvements are determined from energy spectral measurements 2.45 MeV neutrons D(d,n)3He reaction, compressed central core B estimated be ∼4.9 kT using 14.1 secondary D(T,n)4He reactions. experiments...
Experiments examining the amount of specular reflection (or “glint”) within hohlraums containing different gas fill densities have recently been performed. Simulations these experiments are presented that show using a single flux limiter cannot explain decrease in glinted power with increasing density. The hypothesis flow-induced beam deflection alters laser absorption is presented. A model proposed can be implemented into ray tracing description commonly used radiation hydrodynamic codes....
The inertial confinement fusion program relies upon detailed simulations with (ICF) codes to design targets and interpret the experimental results. These treat as much physics from essential principles is practical, including laser deposition, cross beam energy transfer, x-ray production transport, nonlocal thermal equilibrium kinetics, hydrodynamic instabilities, thermonuclear burn, transport of reaction products. Improvements in radiation code capabilities vast increases computing power...
Three similar cryogenic ignition capsule designs for the National Ignition Facility [J. Lindl, Phys. Plasmas 2, 3933 (1995)] are analyzed to determine surface roughness specifications required mitigate growth of hydrodynamic instabilities. These utilize brominated plastic, polyimid and copper-doped beryllium ablator materials respectively. Direct three-dimensional numerical simulations with HYDRA radiation code [M. M. Marinak et al., 3, 2070 (1996)] examine multimode perturbations seeded by...
A sonoluminescing bubble has been modeled as a thermally conducting, partially ionized plasma. The model is more complete than previous models, due to the inclusion of both plasma and normal molecular thermal conduction, vapor pressure, surface tension, mixing gas water in bubble, opacities. accounts for most observed experimental trends, including (i) asymmetric pulse shape; (ii) temperature driving pressure dependence width intensity; (iii) spectral shapes, particular, 300-nm peak spectrum...
Abstract Background and Objective The physical mechanisms for laser‐tattoo interactions the tattoo particle breakup process are not well understood. This study investigates whether mechanism of can be identified via computer simulations proposes a treatment strategy that potentially minimize collateral damage to surrounding tissues. Note “removal” particles is defined here as into smaller ones with sizes approaching or than visible wavelength light so they become less visible. Study...
Z-pinch implosions driven by the SATURN device [D. D. Bloomquist et al., Proceedings of 6th Institute Electrical and Electronics Engineers (IEEE) Pulsed Power Conference, Arlington, VA, edited P. J. Turchi B. H. Bernstein (IEEE, New York, 1987), p. 310] at Sandia National Laboratory are modeled with a two-dimensional radiation magnetohydrodynamic (MHD) code, showing strong growth magneto-Rayleigh–Taylor (MRT) instability. Modeling linear nonlinear development MRT modes predicts bubble-spike...
We have imaged hard x-ray (>100 keV) bremsstrahlung emission from energetic electrons slowing in a plastic ablator shell during indirectly driven implosions at the National Ignition Facility. measure 570 J with E>100 keV impinging on fusion capsule under ignition drive conditions. This translates into an acceptable increase adiabat α, defined as ratio of total deuterium-tritium fuel pressure to Fermi pressure, 3.5%. The observables are consistent detailed radiative-hydrodynamics simulations,...
"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 near the regime when ion mean free paths comparable to capsule size), using RIK model give detailed picture time- and space-dependent structure imploding capsules, allow an assessment relative importance various processes during implosion,...
Turbulent hydrodynamic mixing induced by the Rayleigh–Taylor (RT) and Richtmyer–Meshkov (RM) instabilities occurs in settings as varied exploding stars (supernovae), inertial confinement fusion (ICF) capsule implosions, macroscopic flows fluid dynamics facilities such shock tubes. Turbulence theory modeling have been applied to RT RM developed into a quantitative description of turbulence from onset asymptotic end-state. The treatment, based on combined approach theory, direct numerical...
Using the time-of-flight technique, energy distribution measurements were made of $\ensuremath{\alpha}$ particles emitted from laser implosions DT gas in glass microshells. The number nuclear reactions was determined by an absolute measurement particles. From width distributions, upper limits plasma ion temperature have been inferred.