A5066091076- Laser-Plasma Interactions and Diagnostics
- Laser-induced spectroscopy and plasma
- Laser-Matter Interactions and Applications
- High-pressure geophysics and materials
- Laser Design and Applications
- Nuclear Physics and Applications
- Fusion materials and technologies
- Fluid Dynamics and Turbulent Flows
- Cold Fusion and Nuclear Reactions
- Magnetic confinement fusion research
- Computational Fluid Dynamics and Aerodynamics
- Fusion and Plasma Physics Studies
- Fluid Dynamics and Heat Transfer
- Heat and Mass Transfer in Porous Media
- Nuclear reactor physics and engineering
- Combustion and Detonation Processes
- Fluid Dynamics Simulations and Interactions
- Microtubule and mitosis dynamics
- Additive Manufacturing Materials and Processes
- Neurological disorders and treatments
- Nuclear Issues and Defense
- High-Velocity Impact and Material Behavior
- Advancements in Photolithography Techniques
- Forecasting Techniques and Applications
- Tribology and Lubrication Engineering
University of Rochester
2019-2025
Energetics (United States)
2019-2025
Applied Energetics (United States)
2021-2025
Statistical modeling of experimental and simulation databases has enabled the development an accurate predictive capability for deuterium-tritium layered cryogenic implosions at OMEGA laser [V. Gopalaswamy et al.,Nature 565, 581 (2019)]. In this letter, a physics-based statistical mapping framework is described used to uncover dependencies fusion yield. This model identify quantify degradation mechanisms yield in direct-drive on OMEGA. The found be reduced by ratio beam target radius,...
Nonuniformities present in the laser illumination and target laser-driven inertial confinement fusion experiments lead to an asymmetric compression of target, resulting inefficient conversion shell kinetic energy thermal hot-spot plasma. In this paper, effects cryogenic deuterium tritium laser-direct-drive implosions are examined using a suite nuclear x-ray diagnostics on OMEGA laser. The neutron-averaged velocity (u→hs) apparent ion temperature (Ti) asymmetry determined from neutron...
Improving the performance of inertial confinement fusion implosions requires physics models that can accurately predict response to changes in experimental inputs. Good predictive capability has been demonstrated for yield using a statistical mapping simulated outcomes data [Gopalaswamy et al., Nature 565(771), 581–586 (2019)]. In this paper, physics-based approach is used extract and quantify all major sources degradation direct-drive on OMEGA laser. The found be dependent age deuterium...
Considerable progress has been made in deuterium-tritium-layered implosion experiments on the OMEGA Laser System, bringing prospects for thermonuclear ignition direct-drive configurations with megajoule-class lasers closer to reality. Doing so required navigating balance between improved 1D performance and multidimensional stability. Using statistical modeling based over 350 cryogenic implosions identify various degradation mechanisms, combined simulations experimental techniques such as...
Multidimensional effects degrade the neutron yield and compressed areal density of laser-direct-drive inertial confinement fusion implosions layered deuterium–tritium cryogenic targets on OMEGA Laser System with respect to 1D radiation-hydrodynamic simulation predictions. A comprehensive physics-informed 3D reconstruction effort is under way infer hot-spot shell conditions at stagnation from four x-ray seven detectors distributed around target chamber. Neutron diagnostics, providing...
Finding the optimal implosion design on existing experimental facilities for inertial confinement fusion requires an exhaustive search of vast parameter space. This is infeasible both with experiments and simulations. Consequently, a large fraction experimentally realizable space remains unexplored, new schemes are challenging to optimize in reasonable time frame. On OMEGA laser facility, predictive machine learning models have been developed accurately forecast result experiment using only...
Cryogenic deuterium–tritium ice target implosions on OMEGA with new small-spot (SG5-650) distributed phase plates (DPPs) achieved an (11±4)% increase in energy coupling compared to larger-spot SG5-850 DPPs by decreasing the ratio of laser spot diameter from 0.93 0.75. The SG5-650 provide a focus size 674 μm, which is defined as that encircles 95% measured beam 834 μm for SG5-850, are standard cryogenic OMEGA. hydrodynamic efficiency, kinetic imploding shell energy, increased 4.5% 5.0% based...
Over 300 cryogenic layered direct-drive inertial confinement fusion implosions have been successfully executed on the OMEGA Laser System in last decade. However, extracting sufficient understanding from these experiments to develop new designs or identify mitigate degradation sources remains challenging. Recently, a statistical modeling approach was developed design and predict improved implosion OMEGA. Here, we show that one-dimensional simulations can be used outcomes of systematically...
Multidimensional effects on hot-spot formation must be considered to better understand the current limits performance of direct-drive inertial confinement fusion experiments OMEGA with cryogenically layered solid deuterium–tritium targets. A comprehensive reconstruction effort has been established at Laboratory for Laser Energetics infer and shell conditions stagnation from a large collection x-ray, neutron, particle detectors along multiple lines sight. Several time-gated time-integrated...
The rich and complex physics of inertial confinement fusion provides a unique challenging space for high-fidelity first-principles modeling. Consequently, simulation codes that are used to design experiments computationally expensive lack the predictive capability required extensive parameter exploration in search high-performing laser direct drive. In this article, we present two deep-learning-based models intended address these difficulties. first model (TL DNN) acts as fast emulator...
A deep-learning convolutional neural network (CNN) is used to infer, from x-ray images along multiple lines of sight, the low-mode shape hot-spot emission deuterium–tritium (DT) laser-direct-drive cryogenic implosions on OMEGA. The motivation this approach develop a physics-informed 3-D reconstruction technique that can be performed within minutes facilitate use results inform changes initial target and laser conditions for subsequent implosion. CNN trained 3D radiation-hydrodynamic...
The role of baroclinicity, which arises from the misalignment pressure and density gradients, is well-known in vorticity equation, yet its kinetic energy budget has never been obvious. Here, we show that baroclinicity appears naturally after carrying out appropriate scale decomposition. Strain generation by both barotropic baroclinic, also results our analysis. These two processes underlie recently identified mechanism “baropycnal work”, can transfer across scales variable flows. As such,...
In direct-drive inertial confinement fusion, the laser bandwidth reduces imprinting seed of hydrodynamic instabilities. The impact varying on performance DT-layered implosions was studied in targets with different stability properties. controlled by changing shell adiabat from (${\ensuremath{\alpha}}_{F}\ensuremath{\simeq}5$) (more stable) to (${\ensuremath{\alpha}}_{F}\ensuremath{\simeq}3.5$) (less stable). These experiments show that lower improves considerably as is raised indicating...
We report simulation results that suggest record neutron yields above 3×1014 can be achieved in laser-driven fusion on OMEGA by imploding large-outer-diameter targets (∼1010 μm) containing ice layers as thin 34 μm. Historically, the performance of and fast capsules is thought to highly degraded hydrodynamic instabilities. present pulse designs push implosion velocities 650 km/s while maintaining enough ablative stabilization low in-flight aspect ratios survive acceleration phase. show these...
Observations and computer models are almost always resolution-limited. Is it possible to infer the sub-resolution flow from that we already resolve? This is indeed by performing an operation analogous a Taylor series expansion, but in scale rather than space. What makes this inference property called ``scale-locality,'' which gives us powerful handle on how resolved unresolved structures coupled.
A series of two-dimensional particle-in-cell simulations with speckled laser drivers was carried out to study hot electron generation in direct-drive inertial confinement fusion on OMEGA. Scaling laws were obtained for fraction and temperature as functions laser/plasma conditions the quarter-critical region. Using these scalings from hydro simulations, temporal history can be predicted. The further improved predict hard x-rays a collection OMEGA warm target implosions within experimental...
In laser-driven implosions for laboratory fusion, the comparison of hot-spot x-ray yield to neutron production can serve infer mix. For high-performance direct-drive implosions, this ratio depends sensitively on degree equilibration between ion and electron fluids. A scaling as a function characteristic temperatures is developed basis simulations with varying degrees equilibration. We apply model measurements cryogenic typical designs best ignition metrics. The measured yields indicates that...
Accurate diagnosis of areal density (ρR) is critical for the inference performance metrics in inertial confinement fusion implosions. One potential source error this existence low mode perturbations imploding target, which lead to asymmetries ρR from different lines sight. Here, accrued as a result limited coverage sphere due finite number detectors quantified, and development forward scatter measurement OMEGA neutron time-of-flight motivated. A method by 1D-equivalent 4π-averaged ⟨ρR⟩ can...
We show that an x-ray emission signature associated with acceleration phase mass injection [R. C. Shah et al., Phys. Rev. E 103, 023201 (2021)] correlates poor experimental hot-spot convergence and a reduced neutron production relative to expectations. It is shown increased target as well higher-design adiabats, this reduced, whereas debris on the target, increased. estimate vapor region in typical best designs may have up 2× assumed hydrogen at start of deceleration.Received 5 April...
This paper presents a simple physics-based model for the interpretation of key metrics in laser direct drive. The only input parameters required are target scale, in-flight aspect ratio, and beam-to-target radius, importance each has been quantified with tailored set cryogenic implosion experiments. These analyses lead to compact accurate predictions fusion yield areal density as function hydrodynamic stability, they suggest new ways take advantage To provide examples, we discuss how...