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Light Absorption and Scattering Mechanisms in Laser Fusion Plasmas

Description: The picture of laser light absorption and scattering which is emerging from theory and computer simulation studies of laser-plasma interactions is described. On the subject of absorption, we discuss theoretical and experimental evidence that resonance absorption in a steepened density profile is a dominant absorption mechanism. Recent work also indicates the presence of critical surface ripples, which we study using two and three dimensional computer simulations. Predictions of hot electron spe… more
Date: October 4, 1977
Creator: Barnes, C.; Estabrook, K. G.; Kruer, W. L.; Langdon, A. B.; Lasinski, B. F.; Max, C. E. et al.
Partner: UNT Libraries Government Documents Department
open access

Report of Group II-2: Running at ISA

Description: A discussion is given of the anticipated operating conditions at the ISABELLE storage rings. Communications between experimental and control areas are considered, and beam luminosity monitoring is discussed. Running conditions and expected problems are outlined. (PMA)
Date: August 4, 1977
Creator: Chen, M.; Herrera, J. C.; Littenberg, L.; Thorndike, A.; Ogren, H.; Potter, K. et al.
Partner: UNT Libraries Government Documents Department
open access

Simple scaling model for exploding pusher targets

Description: A simple model has been developed which when normalized by experiment or Lasnex calculations can be used to scale neutron yields for variations in laser input power and pulse length and target radius and wall thickness. The model also illucidates some of the physical processes occurring in this regime of laser fusion experiments. Within certain limitations on incident intensity and target geometry, the model scales with experiments and calculations to within a factor of two over six decades in … more
Date: November 4, 1977
Creator: Storm, E. K.; Larsen, J. T.; Nuckolls, J. H.; Ahlstrom, H. G. & Manes, K. R.
Partner: UNT Libraries Government Documents Department
open access

Vacuum system for the Tandem Mirror Experiment

Description: The Tandem Mirror Experiment (TMX) under construction at LLL is a Q-enhancement experiment using two mirror fields to ''plug'' a central solenoid field. Neutral beam injection supplies the energetic neutrals to the plug regions with attendant quantities of cold gas. The vacuum vessel consists of two large stainless steel tanks, which house the plug coils, joined by an aluminum central cell tank, which fits inside the existing solenoid coils from the 2XIIB experiment. The plug tanks are subdivid… more
Date: October 4, 1977
Creator: Atkinson, D.P.; Calderon, M.O. & Nagel, R.J.
Partner: UNT Libraries Government Documents Department
open access

Automated laser fusion target production concept

Description: A target production concept is described for the production of multilayered cryogenic spherical inertial confinement fusion targets. The facility is to deliver targets to the reactor chamber at rates up to 10 per second and at costs consistent with economic production of power.
Date: October 4, 1977
Creator: Hendricks, C.D.
Partner: UNT Libraries Government Documents Department
open access

Problems associated with transuranium determination of suspended solids in seawater samples

Description: Particulate material collected by filtration from the north Equatorial Pacific Ocean has been analyzed for plutonium and other radionuclides. Different filter pore size, types of filter substrates, flow rates, and sample volumes were evaluated. Retention of /sup 239 +240/Pu was found to vary with the sample volume filtered and was not greatly affected by the type of filter substrate, flow rate, or porosity tested. About 7 +- 3% of the /sup 239 +240/Pu activity in north Equatorial Pacific surfac… more
Date: October 4, 1979
Creator: Wong, K. M.; Jokela, T. A. & Noshkin, V. E.
Partner: UNT Libraries Government Documents Department
open access

Aggregated systems model: a tool for nuclear safeguards decision-making

Description: Setting performance criteria for systems that safeguard special nuclear material (SNM) involves many considerations: characteristics of adversaries attempting to divert SNM, safeguards response to attempts, costs of safeguards systems, and the consequences of diverted SNM. This paper describes an Aggregated Systems Model which is designed to assist decision makers integrate and evaluate consistently these diverse factors. Results from applying the model to a hypothetical facility handling SNM a… more
Date: October 4, 1979
Creator: Al-Ayat, R.; Judd, B. & Huntsman, J.
Partner: UNT Libraries Government Documents Department
open access

Scientific problems of fusion, solved and to be solved

Description: A good comprehensive review of research progress and the present status of research on inertial confinement, tokamak device, and magnetic mirror technology is given. (MOW)
Date: November 4, 1977
Creator: Post, Richard F.
Partner: UNT Libraries Government Documents Department
open access

Design of an eight-megawatt series regulator

Description: An 8-MW, 100 percent duty cycle, hard tube series regulator used to control the accelerating voltage of a neutral beam source is described. The series tube is a developmental switch/regulator tube capable of holding off 200 kV passing 85 A, and dissipating 2 MW of anode power. The regulator has high-speed interrupt capability to minimize the power delivered to the load in the event of a load fault. Its design is such that it can be used to regulate both positive and negative accelerating voltag… more
Date: October 4, 1977
Creator: DeVore, K.R.
Partner: UNT Libraries Government Documents Department
open access

Interactive computerized laboratory data management system

Description: In support of this effort, an average of 55 samples with approximately 4 analyses per sample comes into the ICPP analytical laboratory each day. Information concerning these samples, the 60 people handling the samples, and the 90 methods of running samples is registered, processed, and accessed daily. A manual paper system was found to be inadequate for an efficient, accurate, interacting network; thus, the need for a more spontaneous system emanated. The Analytical Laboratory Computer System i… more
Date: December 4, 1979
Creator: Mirrop, C. A.; Baldwin, J. M.; Camarata, A. R.; Halverson, G. D.; Hand, R. L.; Wade, M. A. et al.
Partner: UNT Libraries Government Documents Department
open access

Two-dimensional magnetohydrodynamic calculations for a 5 MJ plasma focus

Description: The performance of a 5 MJ plasma focus is calculated using our two-dimensional magnetohydrodynamic (2-D MHD) code. Two configurations are discussed, a solid and a hollow anode. In the case of the hollow anode, we find an instability in the current sheath which has the characteristics of the short wave length sausage instability. As the current sheath reaches the axis, the numerical solution is seen to break down. Just before this time, plasma parameters take on the characteristic values rho/rho… more
Date: May 4, 1979
Creator: Maxon, S.
Partner: UNT Libraries Government Documents Department
open access

Spontaneous fission of /sup 259/Md

Description: The mass and kinetic energy distributions of fission fragments from the spontaneous fission of th newly discovered nuclide /sup 259/Md were obtained. /sup 259/Md was identified as the E. C. daughter of /sup 259/No, and was found to decay entirely (> 95%) by spontaneous fission with a 95-min half-life. From the kinetic energies measured for 397 pairs of coincident fragments, a mass distribution was derived that is symmetric with sigma = 13 amu. /sup 259/Md, together with /sup 258/Fm and /sup 259… more
Date: May 4, 1979
Creator: Hulet, E. K.; Wild, J. F.; Lougheed, R. W.; Baisden, P. A.; Landrum, J. H.; Dougan, R. J. et al.
Partner: UNT Libraries Government Documents Department
open access

Absorption and profile modification on spherical targets for. 25 < lambda < 2 microns

Description: LASNEX calculations for focused laser beams on spherical targets have been performed for laser wavelengths of 0.25, 0.5, 1.0 and 2.0 microns. One-dimensional calculations, including the ponderomotive force, show a profile steepening that determines the fractional absorption by anomalous mechanism. However, increased absorption occurs at the shorter wavelengths because of more efficient inverse bremsstrahlung absorption at the higher critical densities. In general, the absorption efficiency incr… more
Date: April 4, 1978
Creator: Larsen, J. T.
Partner: UNT Libraries Government Documents Department
open access

Monitoring natural subsidence and seismicity in the Imperial Valley as a basis for evaluating potential impacts of geothermal production

Description: Results of work done on potential geologic effects of geothermal development are discussed. The key geological issues in the Imperial Valley are the potential for significant subsidence and seismicity which could be induced by geothermal production. The major technical problem is to develop techniques to distinguish between natural and induced activity. In both subsidence and seismicity studies, the projects augment the existing network to obtain additional information in critical areas; thus, … more
Date: April 4, 1978
Creator: Crow, N.B. & Kasamayer, P.W.
Partner: UNT Libraries Government Documents Department
open access

Jet stability in the lithium fall reactor

Description: A preliminary analysis has been made of the various hydrodynamic aspects involved in the stability of a liquid-lithium jet in a laser-fusion reactor, which comprises a part of LLL's laser fusion power-generation concept. Various physical factors that may affect the jet breakup are delineated, and some approximate calculations are performed to determine their relative influences. Areas of uncertainty are pointed out, along with plans for experimental verification or further theoretical analysis.
Date: May 4, 1978
Creator: Kang, S.W.
Partner: UNT Libraries Government Documents Department
open access

Chemical Fingerprints to Assess the Effects of Geothermal Development on Water Quality in Imperial Valley

Description: A two-year baseline water quality study was conducted in the Imperial Valley. The data accumulated, together with the drinking and irrigation water criteria and the known costs of chemical analyses, augment findings on brine chemistry throughout the Valley and on constituents in the Vail 4A Drain, an agricultural drain in the Salton Sea KGRA. These suggest minimum parameters that should be monitored in future programs for water quality management during the development of the geothermal resourc… more
Date: April 4, 1978
Creator: Pimentel, Kenneth D.; Ireland, Robert R. & Tompkins, Gary A.
Partner: UNT Libraries Government Documents Department
open access

Exploding pusher experiments utilizing a 4. pi. illumination system

Description: A focusing system which utilizes two f/0.47 doublets in conjunction with ellipsoidal mirrors produces two focusing cones with half angles of 81.5/sup 0/. This system has been used with the LLL Janus laser system to irradiate and implode DT filled glass microshells approximately 80 ..mu..m diameter. The purpose of the system was to provide more uniform heating of the pusher and compression of the fuel than had been obtained with Janus irradiated targets using f/1 lenses. Neutron yields of approx… more
Date: October 4, 1976
Creator: Storm, E. K.; Ahlstrom, H. G.; Monjes, J. A.; Swain, J. E.; Rupert, V. C. & Phillion, D. W.
Partner: UNT Libraries Government Documents Department
open access

Soft x-ray imaging with a CCD area array

Description: To determine the feasibility of recovering data actively from x-ray imaging instruments used in the Lawrence Livermore Laboratory Laser Fusion Program, a commercial silicon video sensor was used to detect patterns of soft x-rays (1-8 keV). The sensor is a 2-dimensional frame transfer charge coupled device (CCD), modified to allow direct access of x-rays to the sensitive silicon. The x-ray sensitivity, linearity, and dynamic range of the CCD are discussed.
Date: October 4, 1976
Creator: Koppel, L. N. & Eckels, J. D.
Partner: UNT Libraries Government Documents Department
open access

Clinical high-purity germanium gamma-camera

Description: The need in clinical nuclear medicine for imaging devices with high spatial resolution has been discussed at length for many years. More recently, specialists in cardiology and neurology have restated this need for greater resolution in order to effect earlier or more accurate diagnoses of brain tumors, cerebral and myocardial ischemia and infarcts and septum defects, among others. Our approach to filling this need is to ultimately develop a 3072-element, high-purity germanium camera with a 2-m… more
Date: October 4, 1976
Creator: Ewins, J. H.; Armantrout, G. A.; Camp, D. C.; Kaufman, L.; Hattner, R. S.; Price, D. C. et al.
Partner: UNT Libraries Government Documents Department
open access

Acoustic analysis of sodium boiling stability tests using THORS bundle 6A

Description: Acoustic data from boiling stability tests on the THORS (Thermal-Hydraulic Out-of-Reactor Safety) facility are presented and discussed. The THORS sodium loop is a high temperature test facility that contains the bundle 6A, a full length stimulated fuel subassembly with nineteen electrically heated pins. Boiling stability tests on the THORS facility were designed to determine if a stable boiling region exists during the thermal hydraulic test at normal and off-normal conditions. Boiling was obse… more
Date: May 4, 1977
Creator: Sheen, S. H.; Bobis, J. P. & Carey, W. M.
Partner: UNT Libraries Government Documents Department
open access

Exploding pusher experiments utilizing a 4. pi. illumination system

Description: Experiments were performed on the Janus laser with ..cap alpha..- spherical illumination system producing very nearly uniform energy deposition on microscopic laser fusion targets. The target performance as measured by the thermonuclear reaction yield was increased by a factor of 2.5 over experiments performed with f/1 lenses. Simple considerations of useful absorbed energy together with ..cap alpha..-particle time-of-flight measurements indicate that the D-T ion temperatures were not increased… more
Date: October 4, 1976
Creator: Storm, E. K.; Ahlstrom, H. G.; Monjes, J. A.; Swain, J. E.; Rupert, V. C. & Phillion, D. W.
Partner: UNT Libraries Government Documents Department
open access

Transit time spread measurements of microchannel plate photomultipliers

Description: An investigation of the single photoelectron and multi-photoelectron transit time-spread performance of prototype photomultipliers using curved high-gain microchannel plates for electron multiplication and proximity focusing for the input and collector stages is reported. A microchannel plate consists of a closely packed two dimensional array of very small diameter, short channel-electron multipliers. Each single channel electron multiplier is a continuous glass tube whose inside surface has a … more
Date: April 4, 1977
Creator: Keskovar, B. & Lo, C. C.
Partner: UNT Libraries Government Documents Department
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