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Summary form only given. The early evolution of spiral galaxies is modeled with electromagnetic plasma interactions which cause the initial coalescence, rotation, wispy spirals, filamentary structures and magnetic pinches to initiate clumps. As time progresses, the interstellar plasma density decreases, EM plasma effects become weaker and gravitational effects become stronger. Stars are gravitationally...
Summary form only given. Comets have been discovered to be the source of primordial antimatter in our solar system. The announcement was made at April 2002 joint meeting of American Physical Society and American Astronomical Society. When sungrazer comets colliding with the Sun, they produce large sunspots and gigantic solar storms. These enormous ambiplasma storms travel hundreds of millions of kilometers...
Summary form only given. Soon after spacecraft pictures of Lunar surface features became available for detailed analysis, some analysts noted a strong similarity between some of the Lunar craters thought to be caused by impacts of meteorites and craters on surfaces of various materials in the laboratory known to be caused by plasma discharges. While conducting research about the effects of plasma...
Summary form only given. The mass of the outer and inner wire array used to drive the baseline dynamic hohlraum (DH) with pedestal target [Sanford, et al, Phys. Plasmas 13, 1 (2006)] is reversed in order to determine if the outer array is operating in a hydrodynamic- or transparent-like mode [Chittenden, et al, Phys. Plasmas 8, 675 (2001)] when the outer array impacts the inner. In contrast to the...
Summary form only given. Planar wire arrays were shown to produce the strong power and yield in EUV/X-ray region. The new results of the total radiation yield Et, time-resolved sub-keV and keV outputs, X-ray spectra and images from ten wire planar arrays from low-to high-Za materials were collected recently on Zebra at UNR. Data were compared with the similar mass cylindrical wire arrays results....
Summary form only given. We present the design of a broadband multiple-beam klystron (MBK) capable of generating >700 kW of peak RF power with a 3-dB instantaneous bandwidth of >11% at a center frequency of ~3.3 GHz. The MBK will operate in the TM01 fundamental-mode and is designed to be powered by an 18-beam, 42 kV, 41.6 A electron gun that is currently in fabrication. The gun employs a concentric...
Summary form only given. This study presents the first detail 3-D full modeling of all physical processes in laser-produced plasma (LPP) for various applications. The evolution of the target in 3-D full hydrodynamic response coupled with 3-D photon transport in the LPP with detail atomic physics are simulated for multiple-laser on target systems. For example, several concepts are considered in utilizing...
Summary form only given. Electric field distributions are measured around a biased probe immersed in an argon discharge. The distributions are measured as functions of probe bias, argon pressure, and distance of the probe from the "boundary" placed on the plasma by a powered electrode. The electric fields are symmetrically distributed around the probe when the probe is placed sufficiently...
Summary form only given. This paper presents and discusses the phenomenon of fireball ejection from hot spots in solid materials to the atmosphere. The hot spot is created in a substrate material (silicon, germanium, glass, ceramics, basalt, etc.) by the microwave drill mechanism in a reversed mode. A vaporized drop evolves from the molten hot-spot, and is blown up to form a stable fireball buoyant...
Summary form only given. Electron sheaths are electric fields that form near plasma boundaries to preserve quasineutrality in the bulk plasma by reducing the positive ion current lost to a boundary. Previous conjectures hypothesize that electron sheath formation near a positive anode is a solution to the current balance when the ratio of the anode area, Aa, to the chamber wall area, Aw, is less than...
Summary form only given. Conventional methods of decontamination or sterilization are based on using the chemical agents or heat, which may be unapplicable for heat-labile materials, foods etc. It seems possible, that the conventional methods may be appropriately replaced by the nondestructive non-thermal plasma. We studied bactericidal effects of non-thermal plasma generated by the corona discharge...
Summary form only given. In the present investigation we have used plasma focus, as a thin film deposition source, in two different ways: (a) in a conventional way, by replacing the usually used copper anode with a FeCo fitted anode and then depositing the ablated FeCo plasma, the one ablated by the hot plasma and energetic electron beam, on Si substrate placed up the anode axis, the distance between...
Summary form only given. Atmospheric pressure air plasmas are of interest in aeronautic applications, such as electromagnetic wave cross-section reduction. The required electron densities for this application exceed 1011 cm-3 and may vary strongly over small spatial scales. Mapping of the electron density therefore requires diagnostic techniques that provide high spatial resolution. A laser interferometric...
Summary form only given. We have developed a direct NO decomposition system using an intermittent power source, where NO is decomposed in a DBD plasma generated by an intermittent sinusoidal power source. The effects of applied voltage to generate a DBD plasma and gas temperature to the DeNOx rate are mainly investigated. This research is based on the ammonia radical injection DeNOx method using a...
Summary form only given. In this paper, a pulsed power generator that consists of a magnetic pulse compressor (MPC) and a Blumlein-type pulse forming network (BPFN) has been developed. The pulsed power generator can be operated with high repetition rate, long lifetime and high reliability for water treatments such as sterilization of microorganisms, decomposition of harmful materials and ozone generation...
Summary form only given. Biofilms are populations of microorganisms set in a glue-like matrix mostly composed of exopolysaccharides and a small amount of proteins and nucleic acids. Biofilms play an important role in bacterial pathogenesis in humans, animals, and plants, and in bacterial attachments to surfaces such as in medical devices, dental waterlines, etc. Disinfection and sterilization methods...
Summary form only given. Sandia National Laboratories began commissioning the six-stage inductive voltage adder (IVA) configuration of its Radiographic Integrated Test Stand (RITS-6) in 2006. The lower impedance IVA technology results in excess power-flow from the transmission line to the diode region. Schemes to divert the excess flow include attaching a large-radius field shaper ("knob")...
Summary form only given. Tests of nested aluminum (A15056) arrays at the Z accelerator have produced X-ray outputs of >350 kJ. The measured X-rays consist of the K-shell emission of aluminum and magnesium ions, stripped to the He- and H-like states, as well as free-bound continuum. For these tests we recorded these emissions with a variety of spectrometers: time-integrated, spatially resolved and...
Summary form only given. Semi-insulating, compensated silicon carbide (SiC) has been employed in the linear, extrinsic photo-conductive mode as a high power switch. The extrinsic mode is employed for the purpose of increasing the optical absorption depth and thus the area through current can flow. Thus, the dopant densities determine the maximum carrier density and thus the current density is limited...
Summary form only given. Sandia National Laboratories is participating in an intensive research effort into high brightness, electron beam, flash radiographic X-ray sources. One of the sources being investigated is the self magnetic pinch (SMP) diode, that consists of a hollow tapered stalk as the cathode and a bremsstrahlung converter as the anode. The bremsstrahlung converter is comprised of a thin...
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