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Summary form only given. Recently the first hohlraum experiments have been performed at the National Ignition Facility (NIF) in support of indirect drive inertial confinement fusion (ICF) and high energy density (HED) physics. Vacuum hohlraums have been irradiated with laser powers up to 8 TW, 1-9 ns pulse lengths and energies up to 17 kJ to activate several drive diagnostics, to study the hohlraum...
Summary form only given. Two algorithms for the simulation of an ideal two-fluid plasma are presented. The two-fluid model is more general than the often used magnetohydrodynamic (MHD) model. The model takes into account electron inertia effects, charge separation and the full electromagnetic field equations and allows for electron and ion demagnetization. The algorithms used are the wave propagation...
Summary form only given. Inertial-confinement-fusion target designs use multiple shock waves to condition the target material for optimal performance. These designs require that the shock waves be accurately timed to coalesce at a particular point in the target. It is essential that the propagation and dynamics of these multiple shocks be understood and correctly modeled. The OMEGA laser facility...
Summary form only given. In the past, prediction of field-emission properties has generally ignored the space-charged effects caused by the emitted electrons near the emitting surface. Normal procedures of predicting the field-emission properties are, first, to solve the Poisson's equation once and for all and, then, move the emitted electrons following the predicted unchanged electric field. However,...
Summary form only given. Recently it has been shown that wideband microwave pulses are more effective than those composed of single-frequency carriers at generating radio-frequency upset in electronic systems. Nonlinearity in semiconductor junctions down-convert the modulation frequencies off the carrier into baseband signals that may cause logic errors, oscillations and instability in the circuits...
Summary form only given. Energy exchange in a micron-scale zone between a light beam and a free electron beam (EB) can be regulated by control of the EB direction. A 1 V-biased electron deflector may produce light intensity modulation at a rate up to 10% of light frequency. The EB shape, density, and position in effect determine the refractive properties in the exchange zone. High-speed switching,...
Summary form only given. Applying external magnetic fields with megagauss strength is needed for hot plasma confinement and stabilization, with applications from laboratory astrophysics to radiation sources to fusion. We investigate the possibility of generating ultra-high magnetic fields with the fast Z-pinch generator "Zebra" for experiments at the NTF. The high impedance generator can...
Summary form only given. Electron beams in X-pinches generated at the CU XP (current 0.45 MA, 50 ns rise time) facility have been studied from measurements of X-rays >9 keV with 1 ns time-resolved filtered and collimated hard X-ray Si diodes. Early three types of electron beams were observed (V. Kantsyrev et al., Rev. Sci. Instr. 75, 3708 (2003)) in X-pinches. Spatial resolution was 0.4 of the...
Summary form only given. Doped with selected impurities has been shown to be an attractive approach to enhance the properties of amorphous carbon or diamond-like carbon (DLC) films for different application. The surface, mechanical, biological and other properties can be selectively enhanced. In this work, we fabricated calcium, sodium, and phosphorus doped carbon films and evaluated their surface...
Summary form only given. Two different compact plasma focus (PF) devices were developed as soft X-ray sources for microelectronic lithography. This paper will report investigation of soft X-ray emission from plasma focus. Experiments were carried out under various experimental conditions, such as different configurations of PF chamber, different anode lengths, different initial neon pressures, different...
Summary form only given. Spatially-resolved and spatially-integrated X-ray spectral data and time-integrated and time-resolved pinhole X-ray images accumulated from Cu wire arrays and X-pinch experiments on the "Zebra" generator have been analyzed. In particular, Cu wire arrays were investigated with different number of wires and load sizes, and Cu X-pinches implemented with two and four...
Summary form only given. Non-LTE kinetic models of low-Z elements are developed and their applications to Z-pinch and MITL experiments are discussed. In particular, theoretical EUV and X-ray spectra of C, O, and Na ions are presented and calculated for different plasma parameters, which account for different experiments. EUV spectra covered the spectral region of interest from 50 to 600 Aring that...
Summary form only given. Recently, the 1.5 MW, 110 GHz gyrotron with a new cavity has been tested at MIT. The new cavity (V-2005) significantly reduces ohmic loss and, therefore, it is very promising for CW operation of a gyrotron. The gyrotron with the new cavity has been tested in the axial configuration. The maximum power is 1.67 MW in the design mode TE22,6, and the corresponding efficiency is...
Summary form only given. The injection locking technique has been applied on the experiment of gyrotron backward wave oscillator (gyro-BWO) for phase control and spectral purity. The efficiency of the gyro-BWO was considerably enhanced when it was locked by an injected signal, which has never been thorough examined in the locked oscillator. Therefore, the physics underpinning is still unclear. A stationary...
Summary form only given. We present results of emission non-uniformity studies by 3D modeling and experiments on a 96 kV, 40 A magnetron injection gun (MIG) for use in a 1.5 MW 110 GHz gyrotron. Non-uniform beam current density is attributed to emitter surface roughness, surface temperature inhomogeneity, and variation of the work function along the emitting cathode ring. The emission nonuniformity...
Summary form only given. Plasma spectroscopy is an important component for diagnosis and design of laboratory plasma experiments. The advent of plasma-generation devices such as laboratory and FEL-based X-ray lasers, intense ultra-short-pulse lasers, NIF and powerful Z-pinch machines will provide further impetus to develop fast, accurate plasma spectroscopic techniques. The new generation techniques...
Summary form only given. The experimental measurement of the source distribution of flash X-rays produced by intense electron beam diodes for use in deep penetration flash radiography is important. Data on the intensity distribution of the X-ray source is required, both for the development of improved electron beam diodes, and also in order to provide more quantitative information for iterative reconstruction...
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