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Current experiments in elementary particle physics

Description: This report contains summaries of 736 current and recent experiments in elementary particle physics (experiments that finished taking data before 1982 are excluded). Included are experiments at Brookhaven, CERN, CESR, DESY, Fermilab, Tokyo Institute of Nuclear Studies, Moscow Institute of Theoretical and Experimental Physics, Joint Institute for Nuclear Research (Dubna), KEK, LAMPF, Novosibirsk, PSI/SIN, Saclay, Serpukhov, SLAC, and TRIUMF, and also several underground experiments. Also given are instructions for searching online the computer database (maintained under the SLAC/SPIRES system) that contains the summaries. Properties of the fixed-target beams at most of the laboratories are summarized.
Date: September 1, 1989
Creator: Wohl, C. G.; Armstrong, F. E.; Trippe, T. G.; Yost, G. P. (Lawrence Berkeley Lab., CA (USA)); Oyanagi, Y. (Tsukuba Univ., Ibaraki (Japan)); Dodder, D. C. (Los Alamos National Lab., NM (USA)) et al.
Partner: UNT Libraries Government Documents Department

Amorphous silicon detectors in positron emission tomography

Description: The physics of the detection process is studied and the performances of different Positron Emission Tomography (PET) system are evaluated by theoretical calculation and/or Monte Carlo Simulation (using the EGS code) in this paper, whose table of contents can be summarized as follows: a brief introduction to amorphous silicon detectors and some useful equation is presented; a Tantalum/Amorphous Silicon PET project is studied and the efficiency of the systems is studied by Monte Carlo Simulation; two similar CsI/Amorphous Silicon PET projects are presented and their efficiency and spatial resolution are studied by Monte Carlo Simulation, light yield and time characteristics of the scintillation light are discussed for different scintillators; some experimental result on light yield measurements are presented; a Xenon/Amorphous Silicon PET is presented, the physical mechanism of scintillation in Xenon is explained, a theoretical estimation of total light yield in Xenon and the resulting efficiency is discussed altogether with some consideration of the time resolution of the system; the amorphous silicon integrated electronics is presented, total noise and time resolution are evaluated in each of our applications; the merit parameters {epsilon}{sup 2}{tau}'s are evaluated and compared with other PET systems and conclusions are drawn; and a complete reference list for Xenon scintillation light physics and its applications is presented altogether with the listing of the developed simulation programs.
Date: December 1, 1989
Creator: Conti, M. (Istituto Nazionale di Fisica Nucleare, Pisa (Italy) Lawrence Berkeley Lab., CA (USA)) & Perez-Mendez, V. (Lawrence Berkeley Lab., CA (USA))
Partner: UNT Libraries Government Documents Department

Intermediate-field transport of contaminants

Description: This report is about intermediate-field'' transport or the migration of contaminants from arrays of discrete waste packages or sources. In constructing nuclear waste repositories in rock, it may be necessary to place a waste package across a rock fracture, or a rock fracture may develop some time after waste packages have been emplaced. To predict the spatial and temporal distribution of contaminant species from a line of waste packages facing a rock fracture may be important, because such fractures may now be considered a preferential pathway for released radionuclides to re-enter the biosphere. In land disposal of hazardous wastes, individual barrels may contain especially toxic material whose dispersion special attention. We have published analytic solutions for the multidimensional advective transport of contaminants from arrays of waste packages and multiple areal sources into a planar fracture. The results show a near region in which the concentrations vary greatly in the direction transverse to ground-water flow, an intermediate region in which the array can be treated as an infinite plane source of dissolving species, and a far-field region in which the array can be treated as a plane source of finite extent. The array equations have been developed for both porous and fractured media. In this paper we summarize and compare the work with multiple areal sources facing a planar fracture and an array of point sources in porous media. 5 refs., 5 figs.
Date: June 1, 1989
Creator: Ahn, J. (Tokyo Univ. (Japan)); Kim, C. L. (Korea Advanced Energy Research Inst., Seoul (Republic of Korea)); Chambre, P. L.; Pigford, T. H. & Lee, W. W. L. (California Univ., Berkeley, CA (USA). Dept. of Nuclear Engineering Lawrence Berkeley Lab., CA (USA))
Partner: UNT Libraries Government Documents Department

Permeability and dispersivity of variable-aperture fracture systems

Description: A number of recent experiments have pointed out the need of including the effects of aperture variation within each fracture in predicting flow and transport properties of fractured media. This paper introduces a new approach in which medium properties, such as the permeability to flow and dispersivity in tracer transport, are correlated to only three statistical parameters describing the fracture aperture probability distribution and the aperture spatial correlation. We demonstrate how saturated permeability and relative permeabilities for flow, as well as dispersion for solute transport in fractures may be calculated. We are in the process of examining the applicability of these concepts to field problems. Results from the evaluation and analysis of the recent Stripa-3D field data are presented. 13 refs., 10 figs.
Date: January 1, 1990
Creator: Tsang, Y. W. & Tsang, C. F.
Partner: UNT Libraries Government Documents Department

Model estimates of the contributions of environmental tobacco smoke to volatile organic compound exposures in office buildings

Description: Volatile organic compounds (VOC) in office buildings originate from multiple sources, such as outdoor air, building materials, occupants, office supplies, and office equipment. Many of the VOC found in office buildings are also present in environmental tobacco smoke (ETS), e.g., benzene, toluene, formaldehyde. Measurements made to date in Office buildings have been interpreted by some to imply that the contributions to ETS to VOC exposures in office buildings are small. Four different ventilation-infiltration scenarios were modeled for a typical office building. The purpose of this investigation was to provide first-order estimate of the range of contributions of ETS to VOC contributions in office buildings under various ventilation conditions through the use of a mass-balance model and to evaluate the significance of such contributions relative to the VOC concentration measured in office buildings. 25 refs., 1 fig., 4 tabs.
Date: January 1, 1990
Creator: Daisey, J. M.; Gadgil, A. & Hodgson, A. T.
Partner: UNT Libraries Government Documents Department

FMG, RENUM, LINEL, ELLFMG, ELLP and DIMES: Chain of programs for calculating and analyzing fluid flow through two-dimensional fracture networks: Users manuals and listings

Description: The purpose of this report is to provide the user with sufficient information to run the programs FMG, RENUM, LINEL, and ELLFMG. A previous report explained the theory and the design of these programs, so that by using the two reports, a thorough understanding of the codes is possible. This report should familiarize the user with program options and modes of operation, input variables, input and output files. Information not strictly needed to run the programs, but useful in understanding their internal structure is provided in appendices. The appendices cover program variables and arrays, subroutine outlines, a short description of each subroutine, and finally listings of codes. The additional information on FMG, RENUM, LINEL, and ELLFMG is in Appendices A, C, E, G respectively, and the listings are in Appendices B, D, F, and H.
Date: September 30, 1989
Creator: Billaux, D.; Peterson, J.; Bodea, S. & Long, J.
Partner: UNT Libraries Government Documents Department

Seismic characterization of fracture properties

Description: The purpose of this paper is to show that there is a relationship, both empirical and theoretical, between the measured seismic response, the mechanical stiffness (also referred to as specific stiffness) of fractures and their hydraulic conductivity. Laboratory measurements of the mechanical stiffness, hydraulic conductivity and seismic properties of natural fractures are summarized. A theoretical model for the amplitude and group time delay for compressional and shear waves transmitted across a single fracture is presented. Predictions based on this model are compared with laboratory measurements. Finally, the results for a single fracture are extended to multiple parallel fractures. 13 refs., 6 figs.
Date: January 1, 1990
Creator: Myer, L. R.; Hopkins, D.; Cook, N. G. W. (Lawrence Berkeley Lab., CA (USA)) & Pyrak-Nolte, L. J. (Purdue Univ., Lafayette, IN (USA). Dept. of Earth and Atmospheric Sciences)
Partner: UNT Libraries Government Documents Department

Dynamic use of geoscience information to develop scientific understanding for a nuclear waste repository

Description: The development and safety evaluation of a nuclear waste geologic repository require a proper scientific understanding of the site response. Such scientific understanding depends on information from a number of geoscience disciplines, including geology, geophysics, geochemistry, geomechanics and hydrogeology. The information comes in four stages: (1) general regional survey data base, (2) surface-based testing, (3) exploratory shaft testing, and (4) repository construction and evaluation. A discussion is given on the dynamic use of the information through the different stages. We point out the need for abstracting, deriving and updating a quantitative spatial and process model (QSPM) to develop a scientific understanding of site responses as a crucial element in the dynamic procedure. 2 figs.
Date: January 1, 1990
Creator: Cook, N. G. W. & Tsang, C. F.
Partner: UNT Libraries Government Documents Department

In-situ fracture stiffness determination

Description: In-situ experiments to determine the hydrologic and mechanical characteristics of large naturally occurring fractures have been conducted at the NAGRA test site in Grimsel, Switzerland. In addition to seismic measurements across a fracture resulting from pressurization of the zone was also measured. The deformation is modeled in three different ways: as a mathematical crack employing linear elastic fracture mechanics; as a mathematical crack with an additional restraining stiffness between the faces of the crack, and as a row of coplanar two-dimensional cracks. 6 refs., 6 figs.
Date: January 1, 1990
Creator: Hesler, G. J. III (California Univ., Berkeley, CA (USA). Dept. of Materials Science and Mineral Engineering); Zheng, Z. (Terra Tek, Inc., Salt Lake City, UT (USA)) & Myer, L. R. (Lawrence Berkeley Lab., CA (USA))
Partner: UNT Libraries Government Documents Department

Pressure dependence of the specific heat of heavy-fermion YbCu sub 4. 5

Description: The specific heat of a polycrystalline sample of YbCu{sub 4.5} has been measured between 0.3 and 20K at pressures to 8.2 kbar. Unlike cerium-based heavy-fermion compounds, an increase of C/T is observed with increasing pressure, with the linear term enhanced by about 16{percent} at 8.2 kbar. Above 7K, ({partial derivative}C/{partial derivative}P){sub T} is negative. The nuclear contribution observed at P {equals} 0 is increased by roughly a factor of two at 8.2 kbar. 7 refs., 3 figs.
Date: March 1, 1990
Creator: Amato, A.; Fisher, R. A.; Phillips, N. E. (Lawrence Berkeley Lab., CA (USA)); Jaccard, D. & Walker, E. (Geneva Univ. (Switzerland). Dept. de Physique de la Matiere Condensee)
Partner: UNT Libraries Government Documents Department

Modeling studies of the Ahuachapan geothermal field, El Salvador

Description: Modeling studies of Ahuachapan include analyses of interference test data, modeling of the fieldwide pressure decline and the development of a three-dimensional natural state model of the field. The main objective of this work is to obtain reasonable estimates for the transmissivity and storativity of the reservoir and to investigate fluid and heat flow patterns in the system. The analyses of the interference test data and the long term pressure decline data indicate that the average reservoir transmissivity is about 30 Dm and the storativity about 3.5 {times} 10{sup {minus}6} m/Pa. The natural state modeling supports an overall average transmissivity of 25--35 Dm and indicates that the system is recharged with 255{degree}C hot water at a rate of about 225 kg/s. The total thermal throughflow for the Ahuachapan system is estimated to be about 250 MW{sub t}. 10 refs., 11 figs., 3 tabs.
Date: January 1, 1989
Creator: Aunzo, Z.; Steingrimsson, B.; Bodvarsson, G. S. (Lawrence Berkeley Lab., CA (USA)); Escobar, C. & Quintanilla, A. (Comision Ejecutiva Hidroelectrica del Rio Lempa (CEL) (El Salvador))
Partner: UNT Libraries Government Documents Department

Specialty magnets

Description: A number of basic conceptual designs are explained for magnet systems that use permanent magnet materials. Included are iron free multipoles and hybrid magnets. Also appended is a discussion of the manufacturing process and magnetic properties of some permanent magnet materials. (LEW)
Date: July 1, 1986
Creator: Halbach, K.
Partner: UNT Libraries Government Documents Department

Harmonic superspace formalism and the consistent chiral anomaly

Description: The harmonic superspace formalism has been used to construct the consistent chiral anomaly in N = 1, d = 6 supersymmetric Yang-Mills thoery. The expressions of the gauge anomaly ..delta../sub s//sup phi/ and of the supersymmetric anomaly ..delta../sub SUSY//sup phi/ are given together with the consistent condition. 7 refs.
Date: August 1, 1986
Creator: Li, W.
Partner: UNT Libraries Government Documents Department

Comparison of q anti qg and q anti q. gamma. events in e/sup +/e/sup -/ annihilation at PEP

Description: In comparing the particle flow in the event plane of three-jet (q anti qg) events and of radiative annihilation events (q anti q..gamma..) for similar kinematic configurations, two PEP experiments find a significant decrease in particle density in the angular region opposite to the gluon jet in q anti qg events, relative to the particle density in the region opposite to the photon in q anti q..gamma.. events. The effect is predicted both by QCD and by phenomenological string models. 5 refs., 5 figs.
Date: July 1, 1986
Creator: Hofmann, W.
Partner: UNT Libraries Government Documents Department

Physics of very high energy hadron-hadron colliders

Description: A review is given of the physics accessible at a very high energy hadron-hadron collider. Emphasis is placed on the reliability of the predicted rates, and upon the energy and luminosity required to explore new physics options. 38 refs., 19 figs.
Date: September 1, 1986
Creator: Hinchliffe, I.
Partner: UNT Libraries Government Documents Department

Injection and energy recovery in fractured geothermal reservoirs

Description: Numerical studies of the effects of injection on the behavior of production wells completed in fractured two-phase geothermal reservoirs are presented. In these studies the multiple-interacting-continua (MINC) method is employed for the modeling of idealized fractured reservoirs. Simulations are carried out for a five-spot well pattern with various well spacings, fracture spacings, and injection fractions. The production rates from the wells are calculated using a deliverability model. The results of the studies show that injection into two-phase fractured reservoirs increases flow rates and decreases enthalpies of producing wells. These two effects offset each other so that injection tends to have small effects on the usable energy output of production wells in the short term. However, if a sufficiently large fraction of the produced fluids is injected, the fracture system may become liquid-filled and an increased steam rate is obtained. Our studies show that injection greatly increases the long-term energy output from wells, as it helps extract heat from the resrvoir rocks. If a high fraction of the produced fluids is injected, the ultimate energy recovery will increase manyfold.
Date: January 1, 1983
Creator: Bodvarsson, G.S.; Pruess, K. & O'Sullivan, M.J.
Partner: UNT Libraries Government Documents Department

Small-angle x-ray scattering system with linear position-sensitive detector

Description: A linear position-sensitive detector has been constructed for use in small-angle x-ray scattering experiments. It is a one dimensional, pressurized gas-filled detector with a delay line read out. Calculated efficiency of the detector at 8.04 keV and 45 psi for Ar-CH/sub 4/ filling is 60%, and for Xe-CO/sub 2/ filling is 90% limited only by the thickness of the entrance beryllium window. Inherent resolution of the detector is 0.1 mm for normal incident x-rays. The overall resolution of the detection system is determined by the width and angular divergencies of the point collimated CU K/sub ..cap alpha../ beam used in the experiment. The performance of the system is described in terms of measurements on Al-Zn alloy samples.
Date: April 1, 1981
Creator: Forouhi, A.R.; Sleaford, B.; Perez-Mendez, V.; de Fontaine, D. & Fodor, J.
Partner: UNT Libraries Government Documents Department

Experiments on few-electron very high-Z ions

Description: The measurement of the Lamb shift in heliumlike uranium and outlines future experimental tests of QED using few-electron very high atomic number (Z) ions are presented. A discussion of the possibility of using ultrarelativistic atomic collisions to produce very heavy leptons is also presented. 38 refs., 4 figs., 1 tab.
Date: July 1, 1986
Creator: Gould, H. & Munger, C.
Partner: UNT Libraries Government Documents Department

Experiments and prospects for induction linac drivers

Description: In the last three years, the US program in Heavy Ion Fusion has concentrated on understanding the induction linac approach to a power-plant driver. In this method it is important that the beam current be maximized throughout the accelerator. Consequently, it is crucial to understand the space-charge limit in the AG transport system in the linac and, also, to achieve current amplification during acceleration to keep pace with the kinematical increase of this limit with energy. Experimental results on both these matters and also on the use of multiple beams (inside the same accelerating structure) will be described. A new examination of the most attractive properties of the induction linac for a fusion driver has clearly pointed to the advantage of using heavy ions with a charge-state greater than unity - perhaps q = 3 may be an optimum. This development places even greater importance on understanding space-charge limits and mechanisms for emittance growth; also, it will require a new emphasis on the development of a suitable ion source.
Date: May 1, 1986
Creator: D., Keefe
Partner: UNT Libraries Government Documents Department

Highlights of the heavy ion fusion symposium

Description: The current status and prospects for inertial confinement fusion based on the use of intense beams of heavy ions will be described in the light of results presented at the International Symposium on Heavy Ion Fusion, (Washington, DC, May 27-29, 1986).
Date: July 1, 1986
Creator: Keefe, D.
Partner: UNT Libraries Government Documents Department

Nuclear matter equation of state from relativistic heavy ions to supernovae

Description: In this presentation the relationship between relativistic nucleus-nucleus collisions and the nuclear equation of state is discussed. The connection between observables measured in the experiments and thermodynamic variables used to describe the system is made. Through this connection a semi-empirical nuclear equation of state is extracted from the data. The resulting equation of state is discussed in terms of nuclear matter calculations, neutron star stability and supernova collapse. 22 refs., 7 figs.
Date: June 1, 1986
Creator: Harris, J.W.
Partner: UNT Libraries Government Documents Department

Faults and gravity anomalies over the East Mesa hydrothermal-geothermal system

Description: Detailed interpretations of gravity anomalies over geothermal systems may be extremely useful for mapping the fracture or fault systems that control the circulation of the thermal waters. This approach seems to be particularly applicable in areas like the Salton Trough where reactions between the thermal waters and the porous sediments produce authigenic-hydrothermal minerals in sufficient quantity to cause distinct gravity anomalies at the surface. A 3-D inversion of the residual Bouguer gravity anomaly over the East Mesa geothermal field was made to examine the densified volume of rock. We show that the data not only resolve a north-south and an intersecting northwest structure, but that it may be possible to distinguish between the active present-day hydrothermal system and an older and cooler part of the system. The densified region is compared spatially to self-potential, thermal and seismic results and we find a good concordance between the different geophysical data sets. Our results agree with previous studies that have indicated that the main feeder fault recharging the East Mesa reservoir dips steeply to the west.
Date: May 1, 1986
Creator: Goldstein, N.E. & Carle, S.
Partner: UNT Libraries Government Documents Department