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Detailed spatially resolved spectroscopic analysis of a neon gas puff z pinch on the Weizmann 1 MA generator indicates that the radius of the K-shell emitting region grows to a maximum and then decreases during the radiation pulse1,2. ID Lagrangian simulations show the opposite trend because the emission arises from the inside surface of a dense shell that bounces off a hot, stripped central core...
A series of Al/Mg nested wire array Z-pinch load experiments has been recently performed on the refurbished Z accelerator. The earlier comparison study of the results from ID and 2D radiation MHD simulations of the Sandia Z1907/1908 experiments [Y. K. Chong, et. al, APS09] has shown that, in addition to the substantial difference in the prediction capability of the ID and 2D models, the radiation...
A two-dimensional radiation MHD model that includes a self-consistent calculation for non-local thermodynamic equilibrium kinetics and ray trace based radiation transport1 is employed to simulate 65 mm diameter stainless steel double wire array Z machine experiments of 5.0 mg and 2.5 mg, respectively (shots Z1859 and Z1860). Temporal knowledge of the plasma internal energy, ion density, velocity,...
Summary form only given. Fast z-pinches produce intense K-shell radiation from wire arrays and for Cu arrays these photon energies can exceed 8 keV Experimental investigations of pinches on ZR using Cu arrays have already begun and more are planned for the near future. However to produce significant K-Shell emissions from moderately high atomic number plasmas such as Cu, they must be rapidly ionized...
Summary form only given. Full understanding of the dynamics, population kinetics, and energy budget of a K-shell radiating Z-pinch remains a challenging problem in high energy density plasma physics. Recently, detailed axially-imaged spectroscopic measurements were performed on a Ne gas puff driven by the Weizmann generator (500 kA in 500 ns). The Gaussian line widths and measured energy input into...
Summary form only given. A two-dimensional radiation MHD model was recently developed and employed to investigate large diameter wire array Z-pinch experiments performed on the refurbished Z generator. This model incorporates into the Mach2 MHD code a self-consistent calculation for non-local thermodynamic equilibrium kinetics and ray trace based radiation transport. This level of detail is necessary...
We have developed a collisional-radiative spectroscopic model that combines the completeness of highly averaged Rydberg states models with the accuracy of detailed models for all important excited states. Our model includes an abundance of levels and atomic structure data as well as collisional and radiative processes including excitation, ionization, and recombination level couplings. This approach...
Summary form only given. K-shell X-rays have been studied with various materials at the 20-MA (pre-refurbished) Z accelerator. This paper presents results obtained for the ablation dynamics and stagnation physics of single and nested copper z-pinches with varying initial load diameters. Monochromatic imaging and shadowgraphy provide detailed information regarding the ablation of the wires and the...
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