A5049627828- Laser-Plasma Interactions and Diagnostics
- Magnetic confinement fusion research
- Ionosphere and magnetosphere dynamics
- Laser-induced spectroscopy and plasma
- Plasma Diagnostics and Applications
- Electromagnetic Launch and Propulsion Technology
- Solar and Space Plasma Dynamics
- Dust and Plasma Wave Phenomena
- Plasma and Flow Control in Aerodynamics
- High voltage insulation and dielectric phenomena
- Particle accelerators and beam dynamics
- High-Velocity Impact and Material Behavior
- Lightning and Electromagnetic Phenomena
- High-pressure geophysics and materials
- Combustion and Detonation Processes
- Fluid Dynamics and Turbulent Flows
- Advanced Data Storage Technologies
- Astro and Planetary Science
- Electrohydrodynamics and Fluid Dynamics
- Nuclear Physics and Applications
- Advanced Measurement and Detection Methods
- Cold Fusion and Nuclear Reactions
- Gamma-ray bursts and supernovae
- Computational Fluid Dynamics and Aerodynamics
- Thermal Analysis in Power Transmission
Virginia Tech
2016-2022
ORCID
2022
Los Alamos National Laboratory
1998-2015
University of New Mexico
2012-2015
University of Washington
2006-2015
United States University
2015
Los Alamos National Security (United States)
2011
Energetics (United States)
2006-2009
Seattle University
2007
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...
We report experimental results on the parameters, structure, and evolution of high-Mach-number (M) argon plasma jets formed launched by a pulsed-power-driven railgun. The nominal initial average jet parameters in data set analyzed are density \approx 2 x 10^(16) cm^(-3), electron temperature 1.4 eV, velocity 30 km/s, M 14, ionization fraction 0.96, diameter 5 cm, length 20 cm. These values approach range needed Plasma Liner Experiment (PLX), which is designed to use merging form imploding...
We report spatially resolved measurements of the oblique merging two supersonic laboratory plasma jets. The jets are formed and launched by pulsed-power-driven railguns using injected argon, have electron density $\sim 10^{14}$ cm$^{-3}$, temperature $\approx 1.4$ eV, ionization fraction near unity, velocity 40$ km/s just prior to merging. jet produces a few-cm-thick stagnation layer, as observed in both fast-framing camera images multi-chord interferometer data, consistent with collisional...
The stabilizing effect of a sheared axial flow is investigated in the ZaP Z-pinch experiment at University Washington. Long-lived, hydrogen plasmas are generated that 1 m long with an approximately 10 mm radius and exhibit gross stability for many Alfvén transit times. Large magnetic fluctuations occur during pinch assembly, after which amplitude frequency diminish. This stable behaviour continues extended quiescent period. At end period, fluctuation levels increase magnitude frequency....
One-dimensional radiation-hydrodynamic simulations are performed to develop insight into the scaling of stagnation pressure with initial conditions an imploding spherical plasma shell or “liner.” Simulations reveal evolution high-Mach-number (M), annular, flows during convergence, stagnation, shock formation, and disassembly, indicate that cm- μs-scale plasmas peak pressures near 1 Mbar can be generated by liners kinetic energy several hundred kilo-joules. It is shown radiation transport...
We describe a laboratory plasma physics experiment at Los Alamos National Laboratory that uses two merging supersonic jets formed and launched by pulsed-power-driven railguns. The can be using any atomic species or mixture available in compressed-gas bottle have the following nominal initial parameters railgun nozzle exit: n e ≈ i ~ 10 16 cm −3 , T 1.4 eV, V jet 30–100 km/s, mean charge $\bar{Z}$ 1, sonic Mach number M s ≡ / C > 10, diameter = 5 cm, length ≈20 cm. Experiments to date...
We present time-resolved observations of Rayleigh--Taylor-instability (RTI) evolution at the interface between an unmagnetized plasma jet colliding with a stagnated, magnetized plasma. The observed instability growth time ($\sim 10$~$\mu$s) is consistent estimated linear RTI rate calculated using experimentally inferred values density 10^{14}$~cm$^{-3}$) and deceleration 10^9$~m/s$^2$). mode wavelength ($\gtrsim 1$~cm) nearly doubles within time. Theoretical estimates magnetic viscous...
We discuss the design, fabrication, and operation of a liner implosion system at peak currents 16 MA. Liners 1100 aluminum, with initial length, radius, thickness 4 cm, 5 1 mm, respectively, implode under action an axial current, rising in 8 /spl mu/s. Fields on conductor surfaces exceed 0.6 MG. Design fabrication issues that were successfully addressed include: Pulsed Power-especially current joints high magnetic fields possibility electrical breakdown connection cassette insulator to bank...
A fusion space thruster based on the flow-stabilized Z-pinch may be possible in near-term and provide many advantages over other fusion-based concepts. The Zpinch equilibrium is classically unstable to gross disruption modes according theoretical, numerical, experimental evidence. However, a new stabilization mechanism has been discovered that can stabilize these with plasma flow. stabilizing was developed for which an axial velocity profile linear radius. When shear exceeds threshold, are...
Results from inertial confinement fusion (ICF) experiments performed at the Omega laser facility suggest potential role of kinetic effects in plasmas during implosion. Recent theoretical and numerical work has indicated importance diffusion presence multiple ion species as well viscosity. This provides motivation to adequately develop multi-fluid plasma models capable capturing physics including concentration separation driven by gradient, pressure electron temperature gradients, electric...
This study measures the voltage at which flashover occurs in compressed air for a variety of dielectric materials and lengths uniform field DC voltages up to 100 kV. Statistical time lag is recorded characterized, displaying roughly exponential dependence on breakdown voltage. Of tested, acrylic observed be most resistant flashover. These data are intended facilitate design compressed-air insulated high systems as an alternative SF <sub xmlns:mml="http://www.w3.org/1998/Math/MathML"...
We report the characteristics of collisional plasma shocks formed during interactions between low density (ne≈1015 cm−3), temperature (Te≈2 eV), high velocity (30 km s−1), jets and stagnant similar parameters. This investigation seeks to probe structure in multi-ion-species plasmas, particular, presence gradient-driven ion species separation at shock front. The railgun-accelerated utilized here have previously been shown exist a regime with intra-jet mean-free-path substantially smaller than...
Kinetic effects on inertial confinement fusion have been investigated. In particular, inter-ion-species diffusion and suprathermal ion distribution analyzed. The former drives separation of the fuel constituents in hot reacting core governs mix at shell/fuel interface. latter underlie measurements obtained with nuclear diagnostics, including yield inferred burn temperatures. Basic mechanisms behind practical consequences from these are discussed.
Summary form only given. By enabling a fusion ignition regime with plasma density intermediate between that of MFE and ICF, magneto-inertial (MIF) offers the potential for low-cost development path to energy. A standoff driver eliminates repetitive destruction solid materials (e.g., metal liners or transmission lines) further improves attractiveness MIF. With Plasma Liner Experiment (PLX) starting experimental operation at LANL, we are exploring feasibility forming imploding using an array...
An entirely new cylindrical liner system has been designed and fabricated for use on the Shiva Star capacitor bank. The design incorporates features expected to be applicable a future power flow channel of Atlas bank with intention keeping any required modifications minimum when at is available. Four shots were successfully conducted that continued series hydrodynamics physics experiments started Los Alamos Pegasus Departures from diagnostic suite had previously used techniques in...