J. D. Salmonson
A5069612542- Laser-Plasma Interactions and Diagnostics
- Laser-induced spectroscopy and plasma
- Energetic Materials and Combustion
- High-pressure geophysics and materials
- Gamma-ray bursts and supernovae
- Combustion and Detonation Processes
- Laser-Matter Interactions and Applications
- Pulsars and Gravitational Waves Research
- Fusion materials and technologies
- Nuclear Physics and Applications
- Astro and Planetary Science
- Astrophysics and Cosmic Phenomena
- Magnetic confinement fusion research
- Ion-surface interactions and analysis
- Atomic and Molecular Physics
- Cold Fusion and Nuclear Reactions
- Astrophysical Phenomena and Observations
- Nuclear Materials and Properties
- Electromagnetic Launch and Propulsion Technology
- Engineering and Material Science Research
- Mass Spectrometry Techniques and Applications
- Rocket and propulsion systems research
- Infrared Target Detection Methodologies
- Laser Design and Applications
- Computational Fluid Dynamics and Aerodynamics
Lawrence Livermore National Laboratory
2015-2024
Los Alamos National Laboratory
2012-2021
General Atomics (United States)
2012-2021
École Polytechnique
2021
Diamond Materials (Germany)
2021
Massachusetts Institute of Technology
2012-2017
Fusion Academy
2012-2017
Fusion (United States)
2012-2017
University of Rochester
2012-2017
Energetics (United States)
2012-2017
Point design targets have been specified for the initial ignition campaign on National Ignition Facility [G. H. Miller, E. I. Moses, and C. R. Wuest, Opt. Eng. 443, 2841 (2004)]. The contain D-T fusion fuel in an ablator of either CH with Ge doping, or Be Cu. These shells are imploded a U Au hohlraum peak radiation temperature set between 270 300 eV. Considerations determining point include laser-plasma interactions, hydrodynamic instabilities, laser operations, target fabrication....
This paper presents a continuation of our efforts to numerically study accretion disks that are misaligned (tilted) with respect the rotation axis Kerr black hole. Here we present results global numerical simulation which fully incorporates effects hole spacetime as well magnetorotational turbulence is primary source angular momentum transport in flow. shows dramatic differences from comparable simulations untilted disks. Accretion onto occurs predominantly through two opposing plunging...
The National Ignition Facility (NIF) at Lawrence Livermore Laboratory includes a precision laser system now capable of delivering 1.8 MJ 500 TW 0.35-μm light to target. NIF has been operational since March 2009. A variety experiments have completed in support NIF's mission areas: national security, fundamental science, and inertial fusion energy. capabilities infrastructure are place its missions with nearly 60 X-ray, optical, nuclear diagnostic systems. primary goal the Campaign (NIC) on...
Radiative hydrodynamics simulations of ignition experiments show that energy transfer between crossing laser beams allows tuning the implosion symmetry. A new full-scale, three-dimensional quantitative model has been developed for crossed-beam transfer, allowing calculations propagation and coupling multiple their associated plasma waves in hohlraums. This implemented a radiative-hydrodynamics code, demonstrating control symmetry by wavelength separation cones beams.
This Letter reports on a series of high-adiabat implosions cryogenic layered deuterium-tritium (DT) capsules indirectly driven by ``high-foot'' laser drive pulse at the National Ignition Facility. High-foot have high ablation velocities and large density gradient scale lengths are more resistant to ablation-front Rayleigh-Taylor instability induced mixing ablator material into DT hot spot. Indeed, observed spot mix in these was low measured neutron yields were typically 50% (or higher)...
The National Ignition Campaign's [M. J. Edwards et al., Phys. Plasmas 20, 070501 (2013)] point design implosion has achieved DT neutron yields of $7.5\ifmmode\times\else\texttimes\fi{}1{0}^{14}$ neutrons, inferred stagnation pressures 103 Gbar, and areal densities ($\ensuremath{\rho}R$) $0.90\text{ }\text{ }\mathrm{g}/\mathrm{cm}{}^{2}$ (shot N111215), values that are lower than 1D expectations by factors $10\ifmmode\times\else\texttimes\fi{}$, $3.3\ifmmode\times\else\texttimes\fi{}$,...
In order to achieve the several hundred Gbar stagnation pressures necessary for inertial confinement fusion ignition, implosion experiments on National Ignition Facility (NIF) [E. I. Moses et al., Phys. Plasmas 16, 041006 (2009)] require compression of deuterium-tritium fuel layers by a convergence ratio as high forty. Such implosions are subject degradation range perturbations, including growth small-scale defects due hydrodynamic instabilities, well longer scale modulations radiation flux...
The “High-Foot” platform manipulates the laser pulse-shape coming from National Ignition Facility to create an indirect drive 3-shock implosion that is significantly more robust against instability growth involving ablator and also modestly reduces convergence ratio. This strategy gives up on theoretical high-gain in inertial confinement fusion order obtain better control of bring experimental performance in-line with calculated performance, yet keeps absolute capsule relatively high. In...
The recently completed National Ignition Campaign (NIC) on the Facility (NIF) showed significant discrepancies between post-shot simulations of implosion performance and experimentally measured performance, particularly in thermonuclear yield. This discrepancy simulation observation persisted despite concerted efforts to include all known sources degradation within a reasonable two-dimensional (2-D), even three-dimensional (3-D), model, e.g., using surface imperfections radiation drives...
Measurements have been made of the in-flight dynamics imploding capsules indirectly driven by laser energies 1–1.7 MJ at National Ignition Facility [Miller et al., Nucl. Fusion 44, 228 (2004)]. These experiments were part Campaign [Landen Phys. Plasmas 18, 051002 (2011)] to iteratively optimize inputs required achieve thermonuclear ignition in laboratory. Using gated or streaked hard x-ray radiography, a suite ablator performance parameters, including time-resolved radius, velocity, mass,...
We report on the first layered deuterium-tritium (DT) capsule implosions indirectly driven by a "high-foot" laser pulse that were fielded in depleted uranium hohlraums at National Ignition Facility. Recently, high-foot have demonstrated improved resistance to ablation-front Rayleigh-Taylor instability induced mixing of ablator material into DT hot spot [Hurricane et al., Nature (London) 506, 343 (2014)]. Uranium provide higher albedo and thus an increased drive equivalent additional 25 TW...
A new in-flight radiography platform has been established at the National Ignition Facility (NIF) to measure Rayleigh–Taylor and Richtmyer–Meshkov instability growth in inertial confinement fusion capsules. The tested up a convergence ratio of 4. An experimental campaign is underway pre-imposed sinusoidal modulations capsule surface, as function wavelength, for pair ignition-relevant laser drives: “low-foot” drive representative what was fielded during Campaign (NIC) [Edwards et al., Phys....
We present a data-based model for low mode asymmetry in gas-fill hohlraum experiments on the National Ignition Facility {NIF [Moses et al., Fusion Sci. Technol. 69, 1 (2016)]} laser. This is based hypothesis that these fill hohlraums dominated by hydrodynamics of expanding, density, high-Z (gold or uranium) “bubble,” which occurs where intense outer cone laser beams hit wall. developed simple states implosion symmetry becomes more oblate as bubble size large compared to radius capsule...
HYBRID-E is an inertial confinement fusion implosion design that increases energy coupled to the hot spot by increasing capsule scale in cylindrical hohlraums while operating within current experimental limits of National Ignition Facility. reduces hohlraum at a fixed size compared previous HYBRID designs, thereby efficiency and capsule, uses cross-beam transfer (CBET) control symmetry inner (23° 30°) outer (44° 50°) laser beams different wavelengths (Δλ> 0). Small case ratio designs...
We numerically compute light and polarisation curves of gamma-ray burst afterglows for various configurations the jet luminosity structure different dynamical evolutions. especially consider standard homogeneous ``top hat'' ``universal structured jet'' with power-law wings. also investigate a possible more physical variation model: ``Gaussian jet''. The last two types are shown here first time together computation X-ray radio polarised fluxes. show that lightcurves total flux from these very...
The equations governing a flat Robertson-Walker cosmological model containing dissipative Boltzmann gas are integrated numerically. bulk viscous stress is modeled using the Eckart and Israel-Stewart theories of relativistic fluids; resulting cosmologies compared contrasted. models shown to always differ in significant quantitative way from models. It thus appears inappropriate use pathological (nonhyperbolic) theory for applications. For large viscosities, both approach asymptotic...
The full scale modeling of power transfer between laser beams crossing in plasmas is presented. A new model was developed, allowing calculations the propagation and coupling pairs with their associated plasma wave three dimensions. complete set beam smoothing techniques used ignition experiments modeled effects on crossed-beam energy are investigated. shift wavelength can move instability or out resonance hence allows tuning transfer. effective pointing symmetry have been Several designs...
The National Ignition Campaign, tasked with designing and fielding targets for fusion ignition experiments on the Facility (NIF) [G. H. Miller, E. I. Moses, C. R. Wuest, Nucl. Fusion 44, S228 (2004)], has carried forward three complementary target designs past several years: a beryllium ablator design, plastic high-density carbon or synthetic diamond design. This paper describes current simulations design optimization to develop capsule as candidate first attempt NIF. trade-offs in scale...
The National Ignition Campaign (NIC) uses non-igniting “tritium hydrogen deuterium (THD)” capsules to study and optimize the hydrodynamic assembly of fuel without burn. These are designed simultaneously reduce DT neutron yield maintain similarity with ignition capsule. We will discuss nominal THD performance associated experimental observables. show results large ensembles numerical simulations implosions their simulated diagnostic outputs. cover a broad range both off-nominal implosions....
Hydrodynamic instabilities are a major obstacle in the quest to achieve ignition as they cause preexisting capsule defects grow and ultimately quench fusion burn experiments at National Ignition Facility. Unstable growth ablation front has been dramatically reduced implosions with ``high-foot'' drives measured using x-ray radiography of modulations most dangerous wavelengths (Legendre mode numbers 30--90). These reductions have helped improve performance layered DT reported by O. A....
For several years, we have been calculating the radiation drive in laser-heated gold hohlraums using flux-limited heat transport with a limiter of 0.15, tabulated values local thermodynamic equilibrium opacity, and an approximate model for not (NLTE) emissivity (DCA_2010). This has successful predicting vacuum hohlraums, but gas-filled used to capsule implosions, consistently predicts too much bang times earlier than measured. In this work, introduce new that brings calculated time into...
This paper reviews scientific results from the pursuit of indirect drive ignition on National Ignition Facility (NIF) and describes program's forward looking research directions. In NIF, laser beams heat an x-ray enclosure called a hohlraum that surrounds spherical pellet. X-ray radiation ablates surface pellet, imploding thin shell deuterium/tritium (DT) must accelerate to high velocity (v > 350 km s−1) compress by factor several thousand. Since 2009, substantial progress has been made in...