A5061244819- Laser-Plasma Interactions and Diagnostics
- Nuclear Physics and Applications
- Magnetic confinement fusion research
- Plasma Diagnostics and Applications
- Laser-induced spectroscopy and plasma
- Pulsed Power Technology Applications
- Atomic and Subatomic Physics Research
- Cold Fusion and Nuclear Reactions
- Nuclear reactor physics and engineering
- Gyrotron and Vacuum Electronics Research
- Computational Fluid Dynamics and Aerodynamics
- Radiation Detection and Scintillator Technologies
- High-pressure geophysics and materials
- Astro and Planetary Science
- Ion-surface interactions and analysis
- Radiation Therapy and Dosimetry
- Ionosphere and magnetosphere dynamics
- Spacecraft and Cryogenic Technologies
- Combustion and Detonation Processes
Lawrence Livermore National Laboratory
2022-2025
University of California, San Diego
2023
Manufacturing Advocacy & Growth Network (United States)
2023
Lawrence Livermore National Security
2023
Abstract Previous measurements of neutron energy using fast plastic scintillators while operating the Fusion Z Pinch Experiment (FuZE) constrained any yield-producing deuteron beams to less than 4.65 keV. FuZE has since been operated at increasingly higher input power, resulting in increased plasma current and larger fusion yields. A detailed experimental study isotropy these regimes applies more stringent limits possible contributions from beam-target fusion. The device −25 kV charge...
Dense plasma focii (DPFs) are appealing as energy efficient sources of short pulses ions, neutrons, and x rays. The output these is expected to scale with input current (I4), but has been shown drop at the MA level [S. K. H. Auluck, “On failure neutron yield scaling in dense focus,” Phys. Plasmas 30, 080701 (2023)]. New results on MegaJOuLe Neutron Imaging Radiography DPF showed production agreement beyond previously observed drop. This work provides insight into pinch formation a reports...
A targeted experiment at the National Ignition Facility (NIF) confirms presence of multispecies hydrodynamics in inertial confinement fusion hohlraums relevant to ignition. The effects are identified by filling gold hohlraum with a deuterium-tritium (DT) gas mixture instead helium. As is heated NIF lasers, it implodes inward, compressing and heating DT, which leads fusion. resulting DT-fusion neutrons measured space, time, yield, angle, energy. distinct, peaked, triangular shape radial...
The sheared-flow-stabilized Z pinch concept has been studied extensively and is able to produce fusion-relevant plasma parameters along with neutron production over several microseconds. We present here elevated electron temperature results spatially temporally coincident the source. An optical Thomson scattering apparatus designed for FuZE device measures temperatures in range of 1–3 keV on axis device, 20 cm downstream nose cone. 17-fiber system radial profiles temperature. Scanning laser...
Nuclear fusion is a potential source of carbon-free electricity with many concepts in development. The Portable and Adaptable Neutron Diagnostics for Advancing Fusion Energy Science (PANDA-FES) suite has been deployed since 2021 to measure neutron yield, energy, spatiotemporal location at two different Z-pinch devices. This diagnostic can be used variety facilities pursuing the magnetic, inertial, magneto-inertial regimes. These regimes have wide range time scales from less than 100 ns few...
A study on the neutron production from single and double gas puff Z-pinches CESZAR linear transformer driver with ∼0.45 MA current 170 ns rise time is presented. Total yield measurements made a LaBr activation detector are compared for three configurations, using nozzle setup. When single, hollow, deuterium shell was used, reliable implosions could only be attained at higher load mass than optimal value to match implosion time, yields of ∼106 per pulse. The use configuration center jet...
To benchmark the accuracy of models and improve predictive capability future experiments, National Ignition Facility requires measurements physical conditions inside inertial confinement fusion hohlraums. The ion temperature bulk motion velocity gas-filled regions hohlraum can be obtained by replacing helium tamping gas in with deuterium-tritium (DT) measuring Doppler broadening shift neutron spectrum produced nuclear reactions hohlraum. understand spatial distribution production hohlraum,...
We report the plasma pressure reached inside central column of a sheared-flow-stabilized Z-pinch using Thomson scattering measurements. Building on previously reported experimental results and analysis methods established for high temperature moderate density plasmas generated FuZE device, we show evidence region with higher electron density, which is consistent pinch behavior. Elevated temperatures up to 2.25 ± 0.8 keV densities (4.9±0.2)×1017 cm−3 are observed temporally coincide fusion...
On pulsed fusion experiments, the neutron time of flight (nToF) diagnostic provides critical information on energy spectrum. This work presents an analysis technique that uses two collinear nToF detectors, potentially to measure nuclear bang and directional flow velocities. Two detectors may be sufficient disambiguate contributions velocities first moment spectrum, providing independent measurement time. Preliminary results from measured traces National Ignition Facility additional...
A dense plasma focus (DPF) is a coaxial gun that completes its discharge as z-pinch. The MJOLNIR (MegaJOuLe Neutron Imaging Radiography) DPF at LLNL designed for flash neutron radiography. We are designing suite of electromagnetic diagnostics to better understand current flow inside the head. Our goal with these new pinpoint location and timing parasitic paths or restrikes divert from pinch region produces radiation. Based on correlations between traces yields, we hypothesize lower yield...
Neutron diagnostics are used to support the development of a neutron imager and deuterium-based source at Lawrence Livermore National Laboratory MegaJOuLe Imaging Radiography (MJOLNIR) <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">[l]</sup> Dense Plasma Focus (DPF) experiment. The MJOLNIR DPF produces z-pinch like plasma column that generates short (~10s ns), high-yield (several 10 xmlns:xlink="http://www.w3.org/1999/xlink">11</sup> ) pulse....
The MJOLNIR (MegaJOuLe Neutron Imaging Radiography) dense plasma focus (DPF) at LLNL is a prototype source for performing neutron radiography of dynamic events. MJOLNIR's driver can store up to 2 MJ stored energy and produce currents 4.5 MA (so far commissioned >3 MA). DPF consists two coaxial electrodes, which generate sheath by ionizing deuterium gas. implodes on the axis in z-pinch geometry. When pinch breaks apart, it produces beam ions that impacts "target", region assembled past (n_e...
The gas puff Z-pinch is an intense source of neutrons when operated with deuterium [1] . Understanding the mechanisms neutron production in Z-pinches key importance to gain insight on their fundamental physics and viability as a fusion concept. Here, we discuss single double CESZAR Linear Transformer Driver (LTD) at ~0.5 MA currents [3] LTDs are attractive platform conduct experiments, due highly efficient energy conversion high shot rates [2] Comparing implosion trajectory models suggests...