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Polarimeter for protons between 300 and 800 MeV

Description: A polarimeter for protons between 300 and 800 MeV has been constructed. It uses a carbon block analyzer of variable thickness and 6 drift chambers for particle tracking.
Date: January 1, 1980
Creator: Ransome, R.D.; Hollas, C.L.; Greene, S.J.; Bonner, B.E.; McNaughton, M.W.; Morris, C.L. et al.
Partner: UNT Libraries Government Documents Department

(n,p) reaction at 60 MeV on ND-2 targets. [M1 strength, angular distribution, transitions, giant resonance, cross sections]

Description: Various results are presented on energy levels of the isobaric analog resonances produced in the (n,p) reaction on /sup 7/Li, /sup 9/Be, /sup 27/Al, /sup 58/ /sup 60/ /sup 62/ /sup 64/Ni, /sup 90/Zr, and /sup 209/Bi targets. The emphasis is on qualitative features of the data through a comparison with existing results from other nuclear probes as well as observed properties of the isovector transitions anticipated from known isospin selection rules. 21 references. (JFP)
Date: January 1, 1979
Creator: King, N.S.P. & Ullmann, J.L.
Partner: UNT Libraries Government Documents Department

Evaluation of passive solar retrofit options

Description: An evaluation framework has been developed which allows for the assessment of the role of passive solar retrofit in the nationwide reduction of conventional fuel use. Three types of analysis are proposed within this framework: the physical/technical capability of the present housing stock to incorporate passive solar retrofit; the economic feasibility of the application of retrofit designs; and the actual market potential or acceptance of these alternative retrofit options. Each type of analysis has specific data requirements and a series of evaluation procedures to help establish estimates of the potential for passive solar retrofit in the present housing stock. The data requirements with their respective sources and evaluation procedures for the first two types of analysis-physical/technical setting and economic feasibility, are examined. A distinction is drawn between community specific case studies and more generalized national assessments. Information derived from these three types of analysis, whether case specific or national in scope, can then be used in an evaluation of potential economic impacts. The establishment of regional economic benefits and costs werve as a measure of the merit or attractiveness of the implementation of a passive solar retrofit program.
Date: January 1, 1980
Creator: Ben-David, S.; Kirchemen, C.; Martin, S.; Noll, S. & Roach, F.
Partner: UNT Libraries Government Documents Department

Eastern hot dry rock target prospect: a case history

Description: The Eastern Hot Dry Rock Target Prospect is located in a corridor between Smith Island, Maryland on Chesapeake Bay and the southern tip of Assateague Island, Virginia on the Atlantic Ocean. The prospect was selected for investigation based on anomalously high heat flow values and thermal gradients previously determined. The exploration program was aimed at locating the most favorable location within the site area for the targeting of a deep test borehole for HDR heat extraction. The program consisted of an aeromagnetic survey, gravity/magnetic analysis, time-domain electromagnetic (TDEM) survey, Vibroseis seismic reflection profiling, drilling and logging of four 300-meter borings, and the reopening and logging of an abandoned oil exploration hole. The preliminary results of this nearly completed study indicate that the area has potential for the extraction of heat using the Hot Dry Rock concept.
Date: January 1, 1980
Creator: Schubert, C.E.; Maxwell, J.C. & Johnson, W.J.
Partner: UNT Libraries Government Documents Department

Geothermal well stimulation

Description: All available data on proppants and fluids were examined to determine areas in technology that need development for 300 to 500/sup 0/F (150/sup 0/ to 265/sup 0/C) hydrothermal wells. While fluid properties have been examined well into the 450/sup 0/F range, proppants have not been previously tested at elevated temperatures except in a few instances. The latest test data at geothermal temperatures is presented and some possible proppants and fluid systems that can be used are shown. Also discussed are alternative stimulation techniques for geothermal wells.
Date: January 1, 1980
Creator: Sinclair, A.R.; Pittard, F.J. & Hanold, R.J.
Partner: UNT Libraries Government Documents Department

Measurement of the neutron spectrum of the Big Ten critical assembly by lithium-6 spectrometry

Description: The central neutron-flux spectrum of the Los Alamos Scientific Laboratory's critical assembly, Big Ten, was measured with a /sup 6/Li spectrometer and techniques developed at the Centre d'Etude de L'Energie Nucleaire, Mol, as part of an experimental program to establish the characteristics of Big Ten.
Date: January 1, 1979
Creator: De Leeuw-Gierts, G.; De Leeuw, S.; Hansen, G.E. & Helmick, H.H.
Partner: UNT Libraries Government Documents Department

Nuclear structure and the single charge exchange. [150 to 600 MeV]

Description: The influence of nuclear structure on meson-induced single-charge-exchange reactions on light nuclei is discussed within the context of the Glauber approximation. Selection rules which are expected to be approximately obeyed in elastic and inelastic pion and kaon scattering are proposed. Theoretical predictions are presented for (..pi../sup +/,..pi../sup 0/) and (K/sup +/,K/sup 0/) reactions on /sup 13/C. 14 figures.
Date: January 1, 1979
Creator: Oset, E. & Strottman, D.
Partner: UNT Libraries Government Documents Department

Survey of procedures for estimating the distribution of spherical particles from plane sections

Description: Estimating the size distribution of particles in a sample volume from area analysis of a planar slice is one of the difficult fundamental problems of applied stereology. The original formulation of an integral equation by Wicksell (1925) as an approach to this problem led to the development of several procedures for solution, including a simple model of successive differences by Saltikov (1967), a generalized method of successive differences by Lewis et al (1973), a method of moments by Watson (1971), polynominal fits by Minerbo and Levy (1969), spectral differentiation and product integration by Anderssen and Jakemann (1975), and ridge regression and cross validation by Wahba (1979). This discussion presents yet another method (Histogram Method) for solution of the problem, and introduces a constrained minimum variance estimator procedure which eliminates the negative probability anomaly. Several examples of the use of the above methods in analysis of real data are given. The utility of the constrained minimum variance procedure used with the Saltikov and Histogram methods is demonstrated.
Date: January 1, 1979
Creator: Goldman, A.; Lewis, H.D. & Visscher, W.M.
Partner: UNT Libraries Government Documents Department

Economic factors relevant for electric power produced from hot dry rock geothermal resources: a case study for the Fenton Hill, New Mexico, area

Description: The case study described here concerns an HDR system which provides geothermal fluids for a hypothetical electric plant located in the Fenton Hill area in New Mexico's Jemez Mountains. Primary concern is focused on the implications of differing drilling conditions, as reflected by costs, and differing risk environments for the potential commercialization of an HDR system. Drilling costs for best, medium and worst drilling conditions are taken from a recent study of drilling costs for HDR systems. Differing risk environments are represented by differing rate-of-return requirements on stocks and interest on bonds which the HDR system is assumed to pay; rate of return/interest combinations considered are 6%/3%, 9%/6%, 12%/9% and 15%/12%. The method of analysis used here is that of determining the minimum busbar cost for electricity for this case study wherein all costs are expressed in annual equivalent terms. The minimum cost design for the electric generating plant is determined jointly with the minimum cost design for the HDR system. The interdependence between minimum cost designs for the plant and HDR system is given specific attention; the optimum design temperature for the plant is shown here to be lower than one might expect for conventional power plants - in the range 225/sup 0/ to 265/sup 0/C. Major results from the analyses of HDR-produced electricity in the Fenton Hill area are as follows. With real, inflation-free debt/equity rates of 6% and 9%, respectively, the minimum busbar cost is shown to lie in the range 18 to 29 mills/kwh. When real debt/equity rates rise to 12% and 15%, busbar costs rise to 24 to 39 mills/kwh.
Date: December 1, 1979
Creator: Cummings, R.G.; Morris, G.; Arundale, C.J. & Erickson, E.L.
Partner: UNT Libraries Government Documents Department

Directional drilling equipment and techniques for deep hot granite wells

Description: Conventional directional drilling technology has been extended and modified to drill the first well of a subsurface geothermal energy extraction system at the Fenton Hill, New Mexico, Hot dry Rock (HDR) experimental site. Completing the first of a two-wellbore HDR system has resulted in the definition of operational limitations of many conventional directional drilling tools, instrumentation and techniques. The successful completion of the first wellbore, Energy Extraction Well No. 2 (EE-2), to a measured depth of 15,300 ft (4.7 km) in granite reservoir rock with a bottomhole temperature of 530/sup 0/F (275/sup 0/C) required the development of a new high temperature downhole motor and modification of existing wireline-conveyed steering tool systems. Conventional rotary-driven directional assemblies were successfully modified to accommodate the very hard and abrasive rock encountered while drilling nearly 8500 ft (2.6 km) of directional hole to a final inclination of 35/sup 0/ from the vertical at a controlled azimuthal orientation.
Date: January 1, 1980
Creator: Brittenham, T.L.; Sursen, G.; Neudecker, J.W.; Rowley, J.C. & Williams, R.E.
Partner: UNT Libraries Government Documents Department

Representative-vector method for calculating operator-moments

Description: The utility of operator-moments or traces in the various applications of spectral-distribution theory is well documented. To take full advantage of the powerful entree that spectral distribution theory offers in nuclear physics, it may be generally necessary to have many moments beyond th first two hamiltonian moments <H> and <H/sup 2/>. In order to calculate, for one example, level densities reliably in the excitation-energy regions of physical interest, it may be necessary to have the moments <J/sub z//sup 2/H/sup n/> and of course <H/sup n/> with n ranging as high as 8 or so. The subject of this paper is a new method for obtaining these higher moments which is based on the use of random multiparticle vectors, called random representative vectors (RRV), in conjunction with an appropriate shell-model space and hamiltonian. With this method it is possible to calculate average properties of very large spaces with well-defined symmetries by averaging the results over a relatively few RRV. The demonstration of the statistical formulas of the RRV method is given in the next section. In the following section numerical results are given for the test case of 5 nucleons in the single-particle orbits 1d/sub 5/2/, 2s/sub 1/2/; and 1d/sub 3/2/ (A = 21), as well as some results for 12 nucleons in the same orbits plus the 1f/sub 7/2/ orbit (A = 28). With the representative-vector method one can evaluate average moments of any operator O that commutes with H so long as the application of O to the RRV does not produce a new vector which exceeds the memory capacity of the computer. 3 figures, 5 tables. (RWR)
Date: September 1, 1979
Creator: Bloom, S.D. & Hausman, R.F. Jr.
Partner: UNT Libraries Government Documents Department

Solar economic analysis: an alternative approach

Description: Conventional economic analysis which utilizes the discounted present value criterion is examined from a critical perspective. It is found that this technique has a number of limiting characteristics which contribute to the lack of general usage of economic analysis for evaluating passive solar installations. Within this context an alternative approach is suggested for determining the economic desirability of such investments. This latter method, compound future worth analysis, is found to be both more understandable and flexible.
Date: January 1, 1979
Creator: Thayer, M.A.; Brunton, D. & Noll, S.A.
Partner: UNT Libraries Government Documents Department

Passive incentive requirements: a regional assessment

Description: The nation's goal of 20% solar contribution by the turn of the century will be achieved, in part, by the construction of residences heated by virtue of their passive solar designs. These designs are not economically competitive against all conventional fuels in all locations. Some degree of government incentive will be required to assure a competitive position for these designs. A methodology is presented which is used to assess the magnitude of the government incentive required to assure feasibility. The methodology is used to provide a regional assessment for the Pacific Northwest under alternative home ownership periods and conventional fuel types.
Date: January 1, 1980
Creator: Ben-David, S.; Kirschner, C.; Noll, S.A. & Roach, F.
Partner: UNT Libraries Government Documents Department

Review of the experimental results on impurity centers in elemental semiconductors obtained by. mu. SR and other techniques

Description: Selected electron paramagnetic resonance studies of defect centers in group IV semiconductors are reviewed. Features of this research which are useful in analyzing the nature of normal and anomalous muonium (Mu and Mu*) in these crystals are pointed out, and a moderately specific model of Mu and Mu* is presented and compared to studies of hydrogen in silicon and germanium.
Date: January 1, 1980
Creator: Estle, T.L.
Partner: UNT Libraries Government Documents Department

NBS-LASL racetrack microtron

Description: The NBS-LASL racetrack microtron (RTM) is a joint project of the National Bureau of Standards (NBS) and the Los Alamos Scientific Laboratory (LASL). This is a new accelerator research project whose goal is to determine the feasibility of building a high-energy, high-current, cw electron accelerator using beam recirculation and room-temperature rf acceleration structures. The NBS-LASL RTM is being designed and built to develop the required technology for a large national 1 to 2 GeV cw accelerator for nuclear physics research and to prove experimentally that high currents can be accelerated successfully in an RTM. Some of the parameters of the NBS-LASL RTM are 185 MeV final energy, 550 ..mu..A maximum current, 15 passes, 12 MeV one-pass energy gain, and 2380 MHz frequency. One 450 kW cw klystron will supply rf power to both the 5 MeV injector and the 12 MeV linac in the RTM.
Date: January 1, 1980
Creator: Penner, S.; Debenham, P.H. & Green, D.C.
Partner: UNT Libraries Government Documents Department

Physics considerations of the Reversed-Field Pinch fusion reactor

Description: A conceptual engineering design of a fusion reactor based on plasma confinement in a toroidal Reversed-Field Pinch (RFP) configuration is described. The plasma is ohmically ignited by toroidal plasma currents which also inherently provide the confining magnetic fields in a toroidal chamber having major and minor radii of 12.7 and 1.5 m, respectively. The DT plasma ignites in 2 to 3 s and undergoes a transient, unrefueled burn at 10 to 20 keV for approx. 20 s to give a DT burnup of approx. 50%. Accounting for all major energy sinks yields a cost-optimized system with a recirculating power fraction of 0.17; the power output is 750 MWe(net).
Date: January 1, 1980
Creator: Hagenson, R.L. & Krakowski, R.A.
Partner: UNT Libraries Government Documents Department

Reversed-field pinch fusion reactor

Description: A conceptual engineering design of a fusion reactor based on plasma confinement in a toroidal Reversed-Field Pinch (RFP) configuration is described. The plasma is ohmically ignited by toroidal plasma currents which also inherently provide the confining magnetic fields in a toroidal chamber having major and minor radii of 12.7 and 1.5 m, respectively. The DT plasma ignites in 2 to 3 s and undergoes a transient, unrefueled burn at 10 to 20 keV for approx. 20 s to give a DT burnup of approx. 50%. The 5-s dwell period between burn pulses for plasma quench and refueling allows steady-state operation of all thermal systems outside the first wall; no auxiliary thermal capacity is required. Tritium breeding occurs in a granular Li/sub 2/O blanket which is packed around an array of radially oriented water/steam coolant tubes. The slightly superheated steam emerging from this blanket directly drives a turbine that produces electrical power at an efficiency of 30%. A borated-water shield is located immediately outside the thermal blanket to protect the superconducting magnet coils. Both the superconducting poloidal and toroidal field coils are energized by homopolar motor/generators. Accounting for all major energy sinks yields a cost-optimized system with a recirculating power fraction of 0.17; the power output is 750 MWe(net).
Date: January 1, 1980
Creator: Hagenson, R.L. & Krakowski, R.A.
Partner: UNT Libraries Government Documents Department

Reversed-Field Pinch plasma model

Description: The stability of a Reversed-Field Pinch (RFP) is strongly dependent on the plasma profile and the confining sheared magnetic field. Magnetic diffusion and thermal transport produce changing conditions of stability. Despite the limited understanding of RFP transport, modelling is important to predict general trends and to study possible field programming options. To study the ZT-40 experiment and to predict the performance of future RFP reactors, a one-dimensional transport code has been developed. This code includes a linear, ideal MHD stability check based on an energy principle. The transport section integrates plasma profiles forward in time while the stability section periodically checks the stability of the evolving plasma profile.
Date: January 1, 1979
Creator: Miley, G.H.; Nebel, R.A. & Moses, R.W.
Partner: UNT Libraries Government Documents Department

Muon spin rotation and other microscopic probes of spin-glass dynamics

Description: A number of different microscopic probe techniques have been employed to investigate the onset of the spin-glass state in dilute magnetic alloys. Among these are Moessbauer-effect spectroscopy, neutron scattering, ESR of the impurity spins, host NMR and, most recently, muon spin rotation and depolarization. Spin probes yield information on the microscopic static and dynamic behavior of the impurity spins, and give insight into both the spin freezing process and the nature of low-lying excitations in the ordered state. Microscopic probe experiments in spin glasses are surveyed, and the unique advantages of muon studies are emphasized.
Date: January 1, 1980
Creator: MacLaughlin, D.E.
Partner: UNT Libraries Government Documents Department

Power produced from hot dry rock geothermal resources: a case study for the Imperial Valley, California

Description: The case study described here concerns an HDR system which provides geothermal fluids for a hypothetical electric plant located in California's Imperial Valley. Primary concern is focused on the implications of differing drilling conditions, as reflected by costs, and differing risk environments for the potential commercialization of an HDR system. Drilling costs for best, medium and worst drilling conditions are taken from a recent study of drilling costs for HDR systems. Differing risk environments are presented by differing rate of return requirements on stocks and interest on bonds which the HDR system is assumed to pay; rate of return/interest combinations considered are 6%/3%, 9%/6%, 12%/9% and 15%/12%. The method used for analyzing the HDR system involves a two-stage process. In stage 1, the maximum amount that the electric plant can pay to an HDR system for geothermal fluids is calculated for alternative busbar prices of electricity received by the electric plant. In stage 2, costs for the HDR system are calculated under differing assumed risk environments and drilling conditions. These two sets of data may then be used to analyze the minimum busbar price of electricity - which defines a maximum fuel bill that could be paid to the HDR system by the electric plant - which could result in the HDR system's full recouperation of all production and drilling costs.
Date: December 1, 1979
Creator: Cummings, R.G.; Morris, G.E.; Arundale, C.J. & Erickson, E.L.
Partner: UNT Libraries Government Documents Department

Spectral gamma-ray logging II: borehole correction factors

Description: Experimentally determined factors are presented that correct spectral gamma-ray logs for the effects of varying borehole fluid and casing attenuation. These corrections are for gamma-ray spectra from the naturally radioactive isotopes of K, U, and Th. A sodium iodide spectral gamma-ray probe was used to collect data on the 1.46-MeV gamma ray from /sup 40/K, the 1.76-MeV gamma ray from /sup 214/Bi (a decay product of /sup 238/U), and the 2.61-MeV gamma ray from /sup 208/Tl (a decay product of /sup 232/Th). Count rates for these gamma rays were measured for various borehole fluid and casing conditions. Borehole fluid corrections are presented for both centralized and sidewalled probe geometries for hole diameters from 3 to 12 inches. For a typical hole diameter of 4.5 inches and a probe diameter of 2.0 inches, the water correction is 23 percent for the potassium signal, and 15 percent for the uranium and thorium signals. For the smaller borehole diameters, the water correction is nearly independent of probe placement. As the borehole diameter increases to 12 inches, the correction for the uranium and thorium signals increases to 50 percent for the sidewalled geometry and to 100 percent for the centralized geometry. Gamma-ray transport calculations were performed to predict the effects of borehole water for the centralized probe geometry, and the resulting water factor corrections are somewhat lower than the measured values. The difference is attributed to the fact that detector response has not yet been included in the calculations. Casing corrections are presented for dry boreholes with thicknesses of steel casing from 1/16 inch to 1/2 inch. The data are fit reasonably well with exponential curves having effective linear attenuation coefficients of 1.26 inch/sup -1/ for U and 1.03 inch/sup -1/ for Th. 12 figures, 9 tables.
Date: January 1, 1979
Creator: Wilson, R.D.; Stromswold, D.C.; Evans, M.L.; Jain, M. & Close, D.A.
Partner: UNT Libraries Government Documents Department

Spectral gamma-ray logging III: formation and thin bed effects

Description: The effect of borehole formation parameters on spectral gamma-ray probe response was calculated from radiation theory. Results are presented for the effect of formation bulk density and composition on the gamma-ray spectra from potassium, uranium, and thorium. Experimentally determined response functions are presented for spectral gamma-ray probes logging through thin horizontal beds of potassium, uranium, and thorium. Potassium and thorium thin-bed results were obtained by numerical differentiation of the probe response across the interface between a thick zone containing potassium or thorium and a thick barren zone. Uranium results were obtained both from differentiation of thick zone interface measurements and directly using thin bed uranium models. Measurements were performed by use of sodium iodide detectors of various sizes. Detector size and shape were found to have a larger effect on the thin-bed response function than did the formation parameters, which can affect the transport properties of the gamma rays. Results were used to deconvolve observed borehole logs and obtain concentration with depth for thin ore zones. 10 figures, 1 table.
Date: January 1, 1979
Creator: Wilson, R.D.; Stromswold, D.C.; Evans, M.L.; Jain, M. & Close, D.A.
Partner: UNT Libraries Government Documents Department

Modeling and interpretation of two-phase flow and tracer studies from a subbituminous coal seam in the San Juan basin of New Mexico

Description: Field and modeling studies were performed to characterize two-phase flow within the natural cleat structure of an upper Cretaceous subbituminous coal seam. A two borehole pattern with open completion was used in a study of dewatering and tracer residence time distribution. Air was pumped into a five meter thick seam located about 170 meters below the surface. Krypton 85 was used as the airborne tracer. Air inflow and air and water production rates and tracer arrival times were monitored. The field tests were simulated with a two-phase, three component, porous flow code. Results showed that the air inflow and air and water outflow rates and breakthrough times could not be modeled assuming a uniform darcy-type permeability. The use of a pressure dependent permeability did provide, however, a much better match with the field data.
Date: January 1, 1980
Creator: Nuttall, H.E. & Travis, B.J.
Partner: UNT Libraries Government Documents Department

Temperature dependence of anomalous muonium hyperfine interactions in silicon

Description: The temperature dependence of the anomalous muonium hyperfine interaction has been measured in silicon. Between 5 and 150 K, an approximately 1% decrease is observed and attributed to interaction with the silicon host phonons.
Date: January 1, 1980
Creator: Blazey, K.W.; Brown, J.A.; Cooke, D.W.; Dodds, S.A.; Estle, T.L.; Heffner, R.H. et al.
Partner: UNT Libraries Government Documents Department