A5054442759- Fusion materials and technologies
- Laser-Plasma Interactions and Diagnostics
- Nuclear Materials and Properties
- Nuclear Physics and Applications
- Muon and positron interactions and applications
- Laser-induced spectroscopy and plasma
- Plasma Diagnostics and Applications
- Silicon Nanostructures and Photoluminescence
- Nuclear reactor physics and engineering
- Thin-Film Transistor Technologies
- High-pressure geophysics and materials
- Radiation Detection and Scintillator Technologies
- Hydrogen Storage and Materials
- Radioactive contamination and transfer
- Silicon and Solar Cell Technologies
- Metal and Thin Film Mechanics
- Magnetic confinement fusion research
- Ion-surface interactions and analysis
- Particle accelerators and beam dynamics
- Ammonia Synthesis and Nitrogen Reduction
- Cold Fusion and Nuclear Reactions
- Laser-Matter Interactions and Applications
- Nuclear and radioactivity studies
- Hydrogen embrittlement and corrosion behaviors in metals
- Atomic and Molecular Physics
University of Rochester
2016-2025
Energetics (United States)
2014-2025
Applied Energetics (United States)
2013-2024
University of Toronto
1976-2005
Hydro One (Canada)
1994-2003
Kinectrics (Canada)
2002
Ontario Power Generation
2000
Institute of Plasma Physics
1997
Reaching ignition in direct-drive (DD) inertial confinement fusion implosions requires achieving central pressures excess of 100 Gbar. The OMEGA laser system [T. R. Boehly et al., Opt. Commun. 133, 495 (1997)] is used to study the physics that are hydrodynamically equivalent designs on National Ignition Facility (NIF) [J. A. Paisner Laser Focus World 30, 75 (1994)]. It shown highest hot-spot (up 40 Gbar) achieved target with a fuel adiabat α ≃ 4, an implosion velocity 3.8 × 107 cm/s, and...
A record fuel hot-spot pressure ${P}_{\mathrm{hs}}=56\ifmmode\pm\else\textpm\fi{}7\text{ }\text{ }\mathrm{Gbar}$ was inferred from x-ray and nuclear diagnostics for direct-drive inertial confinement fusion cryogenic, layered deuterium--tritium implosions on the 60-beam, 30-kJ, 351-nm OMEGA Laser System. When hydrodynamically scaled to energy of National Ignition Facility, these achieved a Lawson parameter $\ensuremath{\sim}60%$ value required ignition [A. Bose et al., Phys. Rev. E 94,...
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,...
A flexible direct-drive target platform is used to implode cryogenic deuterium–tritium (DT) capsules on the OMEGA laser [Boehly et al., Opt. Commun. 133, 495 (1997)]. The goal of these experiments demonstrate ignition hydrodynamically equivalent performance where drive intensity, implosion velocity, fuel adiabat, and in-flight aspect ratio (IFAR) are same as those for a 1.5-MJ [Goncharov Phys. Rev. Lett. 104, 165001 (2010)] designed ignite National Ignition Facility [Hogan Nucl. Fusion 41,...
Spherically symmetric, low-adiabat (adiabat α ≲ 3) cryogenic direct-drive-implosion experiments on the OMEGA laser [T. R. Boehly et al., Opt. Commun. 133, 495 (1995)] yield less than 10% of neutrons predicted in one-dimensional hydrodynamic simulations. Two-dimensional simulations suggest that this performance degradation can be explained assuming perturbations from isolated defects submicron to tens-of-micron scale outer surface or inside shell implosion targets. These develop during...
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...
Ignition target designs for inertial confinement fusion on the National Facility (NIF) [W. J. Hogan , Nucl. Fusion41, 567 (2001)] are based a spherical ablator containing solid, cryogenic-fuel layer of deuterium and tritium. The need solid-fuel layers was recognized more than 30 years ago considerable effort has resulted in production cryogenic targets that meet most critical fabrication tolerances ignition NIF. At University Rochester’s Laboratory Laser Energetics (LLE), inner-ice surface...
Directly driven implosions on the Omega laser [T. R. Boehly et al., Opt. Commun. 133, 495 (1997)] have measured presence of atomic mix using D+T neutron yield rates from plastic capsules with and without deuterated layers, a nearly pure tritium fuel containing 0.7% deuterium. In 15, 19, 24 μm thick shells, yields increased by factors 86, 112, when 1.2 inner layer was deuterated. Based adjusting fully modvfel to fit degradation in un-deuterated capsule applying it layer, mixing accounts for...
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...
The diagnostic designs for the Laser Megajoule (LMJ) will require components to operate in environments far more severe than those encountered present facilities. This harsh environment be induced by fluxes of neutrons, gamma rays, energetic ions, electromagnetic radiations, and, some cases, debris and shrapnel, at levels several orders magnitude higher experienced today on existing lessons learned about vulnerabilities parts fielded mainly OMEGA many years, have been very useful guide...
The next generation of large scale fusion devices—ITER/LMJ/NIF—will require diagnostic components to operate in environments far more severe than those encountered present facilities. This harsh environment is the result high fluxes neutrons, gamma rays, energetic ions, electromagnetic radiation, and some cases, debris shrapnel, at levels several orders magnitude higher experienced today’s devices. similarities dissimilarities between environmental effects on for inertial confinement...
A new Gas Cherenkov Detector (GCD) with low-energy threshold and high sensitivity, currently known as Super GCD (or GCD-3 at OMEGA), is being developed for use the OMEGA Laser Facility National Ignition (NIF). designed to be pressurized ≤400 psi (absolute) uses all metal seals allow of fluorinated gases inside target chamber. This will gamma energy run low 1.8 MeV 400 C2F6, opening up a portion ray spectrum. operating 20 cm from TCC ∼400 × more efficient detecting DT fusion gammas 16.7 than...
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...
Backlighting is a powerful technique to observe the flow of cold and dense material in high-energy-density–plasma experiments. High-performance, direct-drive cryogenic deuterium–tritium (DT) implosions are challenging backlighting configuration because low opacity DT shell, high shell velocity, small size stagnating very bright self-emission hot core. A crystal imaging system with Si Heα backlighter at 1.865 keV driven by ∼20-ps short pulses from OMEGA EP was developed radiograph implosions....
The newest generation of Gas Cherenkov Detector (GCD-3) employed in Inertial Confinement Fusion experiments at the Omega Laser Facility has provided improved performance over previous generations. Comparison reaction histories measured using two different deuterium-tritium fusion products, namely gamma rays GCD and neutrons Neutron Temporal Diagnostic (NTD), have added credibility to both techniques. GCD-3 is now being brought National Ignition (NIF) supplement existing Gamma Reaction...
Here, we present evidence, in the context of OMEGA cryogenic target implosions, that laser imprint, known to be capable degrading laser-direct-drive performance, plays a major role generating fuel–ablator mix. implosions show performance boundary correlated with acceleration-phase shell stability; for sufficiently low adiabats (where adiabat is ratio pressure Fermi pressure) and high in-flight aspect ratios (IFAR's), neutron-weighted areal density neutron yield relative clean simulated...
The introduction of tritium into hydrogenated amorphous silicon has given rise to a novel material with interesting physical properties and potential applications. Tritium undergoes radioactive decay, transforming 3He+ emitting an electron average energy 5.7 keV, at rate equivalent half-life 12.3 years. decay results in the creation electron–hole pairs formation dangling bonds. Infrared spectroscopy effusion measurements were used analyse bonding network. Electron spin resonance...
The dc saddle-field glow discharge system was used to stably bond tritium in hydrogenated amorphous silicon films. A betavoltaic battery is demonstrated using tritiated-hydrogenated as the intrinsic layer a p–i–n diode and betaconductivity observed a-Si:H:T Although half-life of 12.5 years, decay appeared rapidly increase midgap density states which decreased excess carrier lifetime power from battery. properties film were also affected.
In-line process tritium monitors have been designed, fabricated, and tested for experimental applications in the Tritium Laboratory at Ontario Hydro. The are uniquely simple compact design, ultrahigh vacuum compatible, bakeable to 300°C. low level medium with minimum detection limits of order 1 10 µCi m−3, respectively, linear responses spanning more than 6 decades concentration, flow independent least 0.5 L s−1, exhibit small memory effects rapid recovery following short duration exposures.