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Summary form only given. Vacuum arcs are typically used to form metal plasmas that are nearly 100% ionized, which can then be used to create various types of coatings. The difficulty in forming coatings using an arc plasma is that these devices are also prodigious sources of "macro-particles", or micrometer-sized molten droplets of cathode material that emanate from the arc at high velocity...
Summary form only given. Stimulated Raman scattering (SRS) instability has been experimentally investigated in small-scale halfraums irradiated by intense laser pulses at 10 TW power. The driver energy was delivered by the OMEGA laser (LLE, Rochester) in 1 ns pulses, and deposited in a hot, under-dense Au plasma. The laser energy deposition shifts at later times outside the laser entrance hole (LEH)...
Summary form only given. A new method of ion implantation and plasma coating has been tested to achieve a surface modification of a dielectric thin material which is not suited for plasma based ion implantation (PBII) method. A capacitor of 500 nF charged up to 10 kV was discharged into a 3 cm wide, single-turn coil which surrounds a glass tube of 20 mm O.D. and 16.6 mm I.D. The coil current having...
Summary form only given. We present the design and preliminary results for an imaging system for plasma X-ray sources. The imaging system consists of filters, a compound refractive X-ray lens and CCD camera with an integrated scintillator. This system provides greater resolution images, better than 2 mum resolution, than is readily achievable with pinhole cameras; at 1 mum resolution, the collection...
Summary form only given. During conventional plasma ion implantation, the plasmas are generated uniformly in the vacuum chamber and then the target to be treated is negatively biased. Consequently, all the exposed surfaces are implanted simultaneously. In this paper, a novel plasma ion implantation technique referred to as local source plasma ion implantation is presented. The plasma is produced only...
Summary form only given. Radiofrequency helicon waves are excited in argon, helium, and deuterium at a frequency of 13.56 MHz with input RF powers of up to 2.5 kW using a half-turn double helix antenna. The effect on radial density profiles and ionization efficiency due to nonuniform axial static magnetic field profiles is investigated, with peak magnetic fields of up to 1 kG. The ionization efficiency...
Summary form only given. An appropriate boundary condition describing electron balance at the cathode surface is of fundamental importance to fluid modeling of gas discharges. This boundary condition is conventionally formulated in terms of the escape factor. Various approaches have been applied to evaluation of escape factors. Recently, escape factors for argon have been obtained by means of Monte...
Summary form only given. The stability issue in the gyrotron backward wave-oscillator (gyro-BWO) is the major limitation of demonstrating its capability of broadband and continuous tunability. A time-dependent code is employed to examine the stability of gyro-BWO for either magnetic-field or beam-voltage tuning. Numerical results indicate that shortening the interaction length stabilizes the operation...
Summary form only given. A new generation of materials experiments at high pressures-densities-temperatures is now possible due to a variety of high energy density (HED) facilities and new compression techniques. These facilities will be used over the next decade to measure equation of state and transport properties of materials at multi-gigabar pressure and over 10 fold compression. I will describe...
Summary form only given. The 1 MA Zebra generator has been used to generate plasmas from aluminum wires configured as an X-pinch. X-pinch plasmas are characterized by high-brightness, highly localized emission of >1 keV X-rays. These X-pinch experiments used three different wire types: pure aluminum, an aluminum-magnesium alloy, and pure aluminum coated with magnesium bands. The Mg bands were positioned...
Summary form only given. The X-ray satellite spectra arising due to 2p3/2-13x-1-3x-13d-1 (x = s, p, d) transition array, in elements with Z = 40 to 92, have been calculated. While the energies of various transitions of the array have been determined by using available Hartree Fock-Slater data on 1s-1 -2p-13x-1-1 and 2p3/2-1-3x-1 ,3x'-1, Auger transition energies and their relative intensities have...
Summary form only given. The variation of anode shape is cause to changing the rate of deposition. In this paper, we compared the deposition rate of two kind of copper anode (cylindrical and disk) and then we changed the position magnetic field and studied its effect on the growth copper film in argon and nitrogen gases. Also we investigated the optical properties (by AFM and spectrophotometry) on...
Summary form only given. The characterization of high energy density physics experiments in three dimensions has rarely been undertaken and the capability of measuring in four dimensions currently does not exist. Current high energy density diagnostics measure almost exclusively in two-dimensions and, as such, provide limited ability to benchmark existing and future hydrodynamical codes. We present...
Summary form only given. We present measurements of optical emission spectra in the UV/VUV and visible regions from hollow-slot microplasmas operating at 13.56 and 60 MHz at atmospheric pressure. Spectra are presented for discharges that use helium gas flowing between the electrodes into open air, as well as helium with small admixtures of impurities (nitrogen and hydrogen). We observe that the microplasmas...
Summary form only given. Z pinches are a well established method to produce pulsed X-rays (plasma radiating sources, PRS). Depending on the application, different spectral contents are desired which means that a range of atomic numbers should be available for use in the Z-pinch load. Gas puff loads complement the capabilities provided by wire array loads, offering the use of gases such as neon, argon...
Summary form only given. We have developed a time-dependent, two-dimensional computational model of a magnetized target fusion (MTF) configuration. This consists of an electromagnetically imploded cylindrical metallic liner compressing a target Z-pinch deuterium plasma. A two-dimensional (2-D) Eulerian MHD code has been developed for this purpose. The multimaterial hydrodynamic calculations use the...
Summary form only given. Global positioning satellites (GPS) have been experiencing an anomalous, accelerated degradation of solar array power. This phenomenon, analyzed since the early 80's, remains unexplained. Recently, low-energy (<50 keV) oxygen ions (O+) have been identified as a possible, still unexplored, cause of degradation of solar panel coverglass materials. Oxygen ion implantation...
Summary form only given. A major facility for conducting ionospheric heating experiments is under development in Gakona, Alaska, as part of the high frequency active auroral research program (HAARP). Currently, HAARP HF transmitting system is being expanded from a phased-array antenna of 48 elements to one with 180 elements. After completion of this upgrading, its maximum effective radiated power...
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