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Scattered light evidence for short density heights near critical density in laser-irradiated plasmas

Description: Experimental evidence is presented of a steepened electron density profile near critical density obtained from studying the time-integrated scattered light from targets illuminated by linearly polarized, 1.06 ..mu.. light. Both 10 ..mu.. thick disks and DT-filled glass microshells were irradiated by light focused by f/1 or f/2.5 lenses in one and two-beam experiments, respectively. From the dependence of the asymmetry of the scattered light about the beam axis upon the scattering angle, scale lengths on the order of one micron are inferred. Scale lengths have also been deduced from measurements on the polarization state of the reflected light. Both analytic and numerical results are presented to show how the polarization state varies with the incidence angle and the scale length.
Date: September 15, 1976
Creator: Phillion, D. W.; Lerche, R. A.; Rupert, V. C.; Haas, R. A. & Boyle, M. J.
Partner: UNT Libraries Government Documents Department

Measurement of the widths of emission lines from laser produced plasmas

Description: The targets used for the creation of laser produced plasmas often contain sodium, silicon and other period 3 elements. Temperature and density information can be inferred from detailed study of the characteristic radiation from these elements. The resolution capabilities of crystal spectrographs designed to look at such target radiation are discussed. Data from several types of spectrographs are compared. The fine structure of the hydrogen and helium-like silicon lines are used to illustrate spectrograph resolution. A spectrograph for examining weak characteristic radiation near 1 keV due to plasma which has been compressed with a spherical irradiation system is discussed.
Date: September 15, 1976
Creator: Richards, L. M.; Slivinsky, V. W.; Eckels, J. D. & Glaros, S. S.
Partner: UNT Libraries Government Documents Department

Water supply dilemmas of geothermal development in the Imperial Valley of California

Description: There are four known geothermal resource areas in the Imperial Valley that have a combined potential of over 4,000 megawatts of electrical energy for 25 years. The water resources available to support geothermal energy development are imported Colorado River water, agricultural waste waters, Salton Sea water, and ground water. In addition, geothermal power plants can produce their own cooling water in the form of steam condensate. Nevertheless, the relatively high water requirements of geothermal facilities along with a series of real and potential constraints may cause water supply dilemmas involving both the acquisition and use of cooling water. Important constraints are institutional policies, water supply costs, technical problems, and impacts upon the Salton Sea. These constraints and related dilemmas are examined in light of relevant information on the valley's water resources, geothermal resources and energy technologies, cooling water requirements, and water supply options.
Date: September 15, 1976
Creator: Layton, D. W.
Partner: UNT Libraries Government Documents Department

Scattered light evidence for short density scale heights near critical density in laser-irradiated plasmas

Description: Experimental evidence is presented of a steepened electron density profile near critical density obtained from studying the time-integrated scattered light from targets illuminated by linearly polarized, 1.06 ..mu.. light. Both 10 ..mu.. thick disks and DT-filled glass microshells were irradiated by light focused by f/1 or f/2.5 lenses in one and two-beam experiments, respectively. From the dependence of the asymmetry of the scattered light about the beam axis upon the scattering angle, we infer scale lengths on the order of one micron. Scale lengths have also been deduced from measurements on the polarization state of the reflected light. Both analytic and numerical results are presented to show how the polarization state varies with the incidence angle and the scale length.
Date: September 15, 1976
Creator: Phillion, D. W.; Lerche, R. A.; Rupert, V. C.; Haas, R. A. & Boyle, M. J.
Partner: UNT Libraries Government Documents Department

X-ray detector calibrations in the 183- to 932-eV energy range

Description: The absolute sensitivities of several different types of x-ray detectors were measured between 183 eV and 932 eV. The photons in this energy range were produced by bombarding thin, water-cooled, metal targets with protons from a Cockcroft-Walton ion accelerator. The detectors measured included a silicon-semiconductor detector, two photoelectric-diode detectors employing aluminum and gold photocathodes, and three detectors incorporating plastic scintillators and photodiodes.
Date: October 15, 1976
Creator: Gaines, J. L. & Ernst, R. D.
Partner: UNT Libraries Government Documents Department

Tunable lasers in isotope separation, a colorful view of a dye chemist

Description: Some of the problems to be encountered in the large-scale use of dye lasers in an isotope separation plant are discussed. Why should dye lasers be employed. How can dye conversion efficiency be optimized. How can dye photochemical decomposition and hence running costs be minimized and how serious is this effect anyway. What are toxicity problems with the dye. These and similar issues are examined.
Date: December 15, 1976
Creator: Hammond, P. R.
Partner: UNT Libraries Government Documents Department

Investigation of heat exchanger flow arrangement on performance and cost in a geothermal binary cycle

Description: The performance of an idealized geothermal binary-fluid-cycle energy conversion system is shown to be a function of the temperatures of brine and working fluid leaving the heat exchanger. System power output, heat exchanger area required and initial well and heat exchanger costs are determined for counterflow, single and multi-pass parallel-counterflow exchangers. Results are presented graphically as functions of the brine and working fluid exit temperatures from the exchanger. Use of the system analysis developed is illustrated by showing quantitatively the advantage of the counterflow over the other flow arrangements considered.
Date: June 15, 1976
Creator: Giedt, Warren H.
Partner: UNT Libraries Government Documents Department

Status of large neodymium glass lasers

Description: The elements of a Nd: Glass laser chain as it is constructed for fusion experiments are described. A brief overview of the ARGUS and SHIVA systems employing Nd lasers is given. (MOW)
Date: March 15, 1976
Creator: Glaze, J. A.; Simmons, W. W. & Hagen, W. F.
Partner: UNT Libraries Government Documents Department

Safety and environmental aspects of fusion reactors

Description: Fusion is examined against the yardstick of fission technology with respect to inventories of radioactivity (and associated Biological Hazard Potentials), routine emissions, accident pathways and consequences, radioactive-waste management, and misuse of nuclear materials. Based on conceptual designs of Tokamak fusion reactors with stainless steel structure and tritium inventories of 10 kg per thermal gigawatt, the apparent advantage of fusion is 1 to 2 orders of magnitude in most indices of radiological hazards. Fusion's advantage is 2 to 5 orders of magnitude in comparing damage potential of intentional airborne dispersal of tritium and plutonium, and nonexistent in comparing medium-term radwaste hazard potential (1000 to 100,000 years) and intentional waterborne dispersal of tritium and plutonium. Fusion appears to have some qualitative advantages with respect to accident pathways and safeguards considerations. Fusion has the theoretical potential for improvements of 1 to 2 additional orders of magnitude in short-term BHPs and 3 orders of magnitude and more in radwaste BHPs after 10 years if vanadium-titanium alloy can be used in place of stainless steel in the reactor structure. Other important unresolved questions are how much the inventory of tritium can be reduced by ingenious design, and what fraction of a fusion reactor's activation products could be volatilized and released in a severe accident such as a lithium fire. Overall, fusion's potential advantages are appreciable but not automatic--it will require early and sustained attention to environmental characteristics to avoid losing some of the potential advantages in pursuit of other goals.
Date: October 15, 1976
Creator: Holdren, J. P.
Partner: UNT Libraries Government Documents Department

Measurement of high energy ions. [Time-of-flight spectrometer]

Description: The current interest in fast ions has prompted the design of a new time-of-flight ion spectrometer which measures the high energy ions from a laser produced plasma. A magnet was used to separate the ions from the intense background of electrons, x-rays and scattered light. The design of the instrument is wide band so that ions with energies 0.03 to 3000 keV/amu can be measured. Results from target experiments on the LLL ARGUS laser facility will be presented. The fast ion spectrum is dovetailed with the spectrum of the slower ions collected by Faraday cups and thus provides a measurement for the total energy carried by ions. The charge to mass ratio of the ions can be calculated from the spectrometer output.
Date: September 15, 1976
Creator: Glaros, S. S.; Tirsell, K. G.; Rupert, V. C.; Catron, H. C. & Slivinsky, V. W.
Partner: UNT Libraries Government Documents Department

Equilibrium constants for the hydrogen isotopic self-exchange reactions in the 4. 2-50. 0 K temperature range

Description: Hydrogen fusion will require a mixture of liquefied or frozen D/sub 2/ and T/sub 2/. The equilibrium constant of the mixture describes the composition of this fuel. We have calculated the equilibrium constant, K/sub DT/, for the reaction D/sub 2/ + T/sub 2/ = 2DT in the 4.2-100 K temperature range. The results agree well with previous calculations at 25, 50, and 100 K. No calculations at temperatures below 25 K have been previously published. In the 16.7 to 33.3 K temperature range, which includes the triple point, K/sub DT/ can be represented by K = 2.995 exp (-10.82/T). The values of the analogous equilibrium constants for H/sub 2/--D/sub 2/ and H/sub 2/--T/sub 2/ are also given in the 4.2 to 50 K temperature range.
Date: December 15, 1976
Creator: Pyper, J. C. & Souers, P. C.
Partner: UNT Libraries Government Documents Department

Calculation of emission from hydrogenic ions in super liquid density plasmas

Description: Previous calculations of line emission were extended to higher density, lower temperature plasmas, typical of those expected in early ablative compression experiments. Emission from Ne-seeded fuel was analyzed in order to diagnose the density and temperature of the compressed core. The Stark/Doppler broadened emission profile is calculated for the H-like Ne resonance line. The observable lineshape is then obtained by time-averaging over expected density and temperature profiles and by including the effects of radiative transfer.
Date: November 15, 1976
Creator: Bailey, D. S. & Valeo, E. J.
Partner: UNT Libraries Government Documents Department

Comparison of bedrock and surface seismic input for nuclear power plants

Description: Current practice in the nuclear industry and elsewhere is to specify the seismic input to design calculations at the surface of the site, rather than at bedrock. This paper investigates the implications of such a specification by comparing the site response of a surface specification to the site response of a corresponding bedrock specification. The investigation considered six different sites consisting of three soil profiles with average shear wave velocities of 800, 1800, and 5000 ft/sec and two oil depths: 200 ft. and 400 ft. Seismic input to these sites consisted of two synthetic accelerograms: one corresponding to Blume's statistically averaged surface response spectrum taken as surface input, the other accelerogram was, in our judgment, a typical bedrock acceleration time history related to the surface synthetic accelerogram. The site response was calculated using the program SHAKE. The deconvolution results indicate that Blume's statistically averaged surface response spectrum envelops all the spectra from lower levels for hard and intermediate sites. When the corresponding bedrock acceleration is used as input for a convolution, the surface acceleration can be greater than Blume's surface spectral acceleration. It is very difficult to calculate physically meaningful results for the soft sites for both convolution and deconvolution. These difficulties are certainly related to physical constraints on the input.
Date: January 15, 1976
Creator: Zaslawsky, M. & Wight, L.
Partner: UNT Libraries Government Documents Department