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Double Planar Wire Arrays (DPWA), which consist of two parallel rows of wires, have previously demonstrated high radiation efficiency, compact size, and usefulness for various applications in experiments on a University-scale high-impedance Z-pinch generator1. Recently, we successfully performed two experimental campaigns with PWAs on the University of Michigan's low-impedance MAIZE (Linear Transformer...
A gas jet containing a mixture of monomers and clusters was characterized and studied as an x-ray radiation source produced by a TW-class laser pulse. Gas jet parameters such as average density and cluster size were measured at the UNR Radiation Physics Laboratory using both optical interferometry and Rayleigh scattering techniques, respectively. Several noble gases were used in the gas jet: Ar, Kr,...
Some aspects of physical phenomena occurring when an intense laser pulse with sub-ps duration and intensity > 1018-1019 W/cm2 heats under-dense plasma in supersonic clusters/gas jet from gas-puff system were studied to determine the relative contribution of these processes to soft and hard x-ray emission from debris-free plasmas. Experiments were performed at the UNR Leopard laser operated with...
Linear Discriminant Analysis (LDA) is applied and compared with the Principal Component Analysis (PCA) and the H- and He-like line ratio diagnostics to investigate the electron beam effects on the laser produced K-shell Al synthetic spectra1,2. The experiments were performed at the Leopard Laser Facility of NTF/UNR (1.057 μm Ti:Sapphire/Nd:glass laser system) with 0.8 ns pulses with 15 J of energy,...
Single Planar Wire Arrays (SPWA) and Double Planar Wire Arrays (DPWA), which consist of one or two parallel rows of wires, respectively, have demonstrated high radiation efficiency (up to 30 kJ), compact size (1.5–3 mm), and usefulness for various applications in experiments on the high-impedance Zebra (1.9Ω, 1 MA, 100 ns). For example, DPWAs are very suitable for the new compact multi-source hohlraum...
A new compact Z-pinch x-ray hohlraum design with multiple parallel-driven x-ray sources was jointly proposed by the Sandia National Laboratories and the University of Nevada [1]. The first proof-of-principle experimental demonstration of the full configuration of this compact hohlraum with central reemission target and tailored shine shields (to provide a symmetric temperature distribution on the...
Load Current Multiplier (LCM) continues to be successfully applied on Zebra at UNR. Here we consider further, expanded applications of LCM. Time-shaping of magnetic pressures on pulsed facilities is useful for such a number of High Energy Density Physics (HEDP) applications such as dynamic material properties studies1,2, high gain ICF research3 and instability growth studies4. The Dynamic LCM (DLCM)...
Previous experiments on the 1 MA Zebra generator at UNR studied precursor plasmas with Ni-60 cylindrical wire arrays (CWA). Those precursor plasmas were shown to consistently have electron temperatures > 400 eV1. Continuing research on precursor plasmas at 1 MA on Zebra investigated first other mid-Z wire materials and then alternate arrays using mixed Al/mid-Z CWAs. Results found similar electron...
Experiments on the Zebra generator with LCM (Load Current Multiplier, provides 1.5–1.7 MA) allow for implosions of larger sized wire array loads (including planar wire arrays) than at standard current of 1 MA. Advantages of larger sized planar wire array implosions include enhanced energy coupling to plasmas and better diagnostic access to observable plasma regions. A full set of diagnostics was implemented...
Extreme ultraviolet (EUV) radiation from z-pinch plasma sources has been shown to play a substantial role in the evolution of z-pinches, contributing significant amounts of radiation in the wire ablation, stagnation, and plasma expansion phases1. Recent studies of Cu z-pinch plasmas from cylindrical wire arrays have also shown that high temperatures (up to 450 eV) exist in precursor plasmas, which...
Planar foil liners are alternative loads to wire arrays at multi-mega ampere generators as well as a promising object for the investigation of the magnetic energy dissipation mechanisms in Z-pinch plasmas. Experimental comparison of implosion dynamics and radiative mechanisms of Al planar foils and single planar wire arrays (SPWAs) of the same width and linear mass was performed for the 0.9–1.6-MA...
An improved load current multiplier (LCM) was designed and tested on a high-voltage 100 ns, 0.8–1 MA generator Zebra. The new design allowed to achieve up to ∼1.7 MA in plasma loads and up to 1.9 MA in static loads [1]. The previous LCM version provided 1.4 and 1.6 MA accordingly [2]. The load current increase results in the increase of X-ray yield and power from plasma radiation source loads [3]...
Summary form only given. The planar wire array research on Zebra at UNR that started in 2005 continues experiments with new types of planar loads with results for consideration and comprehensive analysis [see, for example, Kantsyrev et al, HEDP 5, 115 (2009)]. The detailed studies of radiative properties of such loads are important and spectroscopy and imaging constitute a very valuable and informative...
Summary form only given. Triple Planar Wire Arrays (TPWA) consisted from three planes made of Mo (uniform) or from Mo and Al wire planes (combined). Each plane from Mo or Al wires was almost the same mass and therefore the total linear mass of both uniform and combined TPWAs was about 115 μg/cm. The previous results with 3 mm between planes are revisited. New experiments with the same TPWAs but with...
X-pinches are very good sources of x-rays and can be used for studying radiative properties of high density and temperature plasmas with scale from a few μm to several mm in size. An X-pinch is formed by the touch-crossing of two or more wires between the electrodes of a high-current pulsed-power generator. As a result of current quickly vaporizing and strongly ionizing the wire material, X-pinch...
Summary form only given. Radiographs of X-pinches driven by ~400 kA current pulses show jets of matter extending along the anode-cathode axis from both sides of the crossing point of the X pinch wires. The jets, formed by ablation of material from the heated wires of the X pinch, extend over a few mm of the 15 mm anode-cathode gap and persist over tens of ns during the X-pinch implosion. Spatially...
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