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N = 2 Maxwell-Einstein Supergravity theories: their compact and non-compact gaugings and Jordan algebras

Description: In this talk we give a review of our work on the construction and classification of N = 2 Maxwell-Einstein Supergravity theories (MESGT), study of the underlying algebraical and geometrical structure of these theories, and their compact and non-compact gaugings. We begin by summarizing our construction of the N = 2 MESGT's in five dimensions and give a geometrical interpretation to various scalar dependent quantities in the Lagrangian, based on the constraiants implied by supersymmetry. This is followed by a complete classification of the N = 2 MESGT's whose target manifolds parametrized by the scalar fields are symmetric spaces. 39 refs.
Date: January 1, 1985
Creator: Guenaydin, M.; Sierra, G. & Townsend, P.K.
Partner: UNT Libraries Government Documents Department

3-body final states in peripheral heavy-ion collisions: nuclear clustering structure and projectile excitation revisited

Description: Even though peripheral heavy-ion collisions are less violent than their central counterparts, the large energy exchange between the reactants often leaves the primary products in excited particle-unstable states whose subsequent decay leads to 3 or more nuclei emerging in the final exit channel. These post-reaction, predominantly sequential de-excitation processes can sometimes provide interesting structural information about the parent nuclei. In fact, provided these processes are well understood, one can employ them as probes for studying initial properties of the fragments. This report discusses results of two experiments that deal with (1) nonstatistical, rare decay modes of the projectile, and (2) internal excitation energy of the projectile- and target-like fragments in peripheral collisions. The physics addressed in each is different, but the experimental and data-analysis techniques are so similar that it is relevant to join them together.
Date: February 1, 1986
Creator: Chan, Y.; Chavez, E.; Gazes, S.B.; Kamermans, R.; Schmidt, H.R.; Siwek-Wilczynska, J. et al.
Partner: UNT Libraries Government Documents Department

4. pi. data of relativistic nuclear collisions. [Plastic ball]

Description: During the past two years, complete events of relativistic nuclear collisions are being studied with the Plastic Ball, the first electronic nonmagnetic particle-identifying 4..pi.. spectrometer. It is well suited to handle the large multiplicities in these reactions and allows collection of data at a rate sufficient to make further software selections to look at rare events. The analysis of the data follows various lines covering topics like thermalization, stopping or transparency, cluster-production mechanism (--can it tell entropy), search for collective flow through various global analyzing methods that allow determination of the scattering plane, projectile fragmentation (--is there a bounce-off), pion distribution, two-particle correlations: Hanbury-Brown Twiss, and excited nuclear states (--nucleosynthesis at the freezeout point or from chemical equilibrium). We will cover in this contribution only two subjects: stopping and thermalization and cluster production.
Date: May 1, 1983
Creator: Gutbrod, H.H.; Gustafsson, H.A. & Kolb, B.
Partner: UNT Libraries Government Documents Department

4. pi. physics with the plastic ball

Description: 4 ..pi.. data taken with the Plastic Ball show that cluster production in relativistic nuclear collisions depends on both the size of the participant volume and the finite size of the cluster. The measurement of the degree of thermalization and the search for collective flow will permit the study of the applicability of macroscopic concepts such as temperature and density.
Date: October 1, 1982
Creator: Gutbrod, H.H.; Loehner, H.; Poskanzer, A.M.; Renner, T.; Riedesel, H.; Ritter, H.G. et al.
Partner: UNT Libraries Government Documents Department

6. 4 Tesla dipole magnet for the SSC

Description: A design is presented for a dipole magnet suitable for the proposed SSC facility. Test results are given for model magnets of this design 1 m long and 4.5 m long. Flattened wedge-shaped cables (''keystoned'') are used in a graded, two-layer ''cos theta'' configuration with three wedges to provide sufficient field uniformity and mechanical rigidity. Stainless steel collars 15 mm wide, fastened with rectangular keys, provide structural support, and there is a ''cold'' iron flux return. The outer-layer cable has 30 strands of 0.0255 in. dia NbTi multifilamentary wire with Cu/S.C. = 1.8, and the inner has 23 strands of .0318 in. dia wire with Cu/S.C. = 1.3. Performance data is given including training behavior, winding stresses, collar deformation, and field uniformity.
Date: May 1, 1985
Creator: Taylor, C.E.; Caspi, S.; Gilbert, W.; Meuser, R.; Mirk, K.; Peters, C. et al.
Partner: UNT Libraries Government Documents Department

6. 4 tesla dipole magnet for the SSC. Revision

Description: A design is presented for a dipole magnet suitable for the proposed SSC facility. Test results are given for model magnets of this design 1 m long and 4.5 m long. Flattened wedge-shaped cables (''keystoned'') are used in a graded, two-layer ''cos theta'' configuration with three wedges to provide sufficient field uniformity and mechanical rigidity. Stainless steel collars 15 mm in radial depth, fastened with rectangular keys, provide structural support, and there is a ''cold'' iron flux return. The outer-layer cable has 30 strands of 0.648 mm diameter NbTi multifilamentary wire with Cu/S.C. = 1.8, and the inner has 23 strands of 0.808 mm diameter wire with Cu/S.C. = 1.3. Performance data are given, including training behavior, winding stresses, collar deformation, and field uniformity. 10 refs., 11 figs.
Date: August 1, 1985
Creator: Taylor, C.E.; Caspi, S.; Gilbert, W.; Hassenzahl, W.; Meuser, R.; Mirk, K. et al.
Partner: UNT Libraries Government Documents Department

300-element silicon-lithium position-sensitive imaging detector for angiography

Description: Silicon lithium-drifted (Si(Li)) detectors 150 mm long, 10 mm wide and 5 mm thick with 300 individual elements have been fabricated as imaging detectors for noninvasive studies of human coronary arteries using 33 keV x-rays from a synchrotron radiation beamline. This detector is an extension of earlier work on 30 mm long devices with initially 30 and later 60 elements. The detector fabrication details are discussed highlighting problems in uniform lithium-ion compensation. The device structure is examined and measurements on the interelement impedances presented. Finally an angiograph of the coronary arteries in an excised pig's heart obtained with this 300-element detector is presented. 14 refs., 6 figs.
Date: October 1, 1985
Creator: Walton, J.T.; Sommer, H.A.; Thompson, A.C.; Hughes, E.B. & Zeman, H.D.
Partner: UNT Libraries Government Documents Department

500-kW DCHX pilot-plant evaluation testing

Description: Field tests with the 500 kW Direct Contact Pilot Plant were conducted utilizing brine from well Mesa 6-2. The tests were intended to develop comprehensive performance data, design criteria, and economic factors for the direct contact power plant. The tests were conducted in two phases. The first test phase was to determine specific component performance of the DCHX, turbine, condensers and pumps, and to evaluate chemical mass balances of non-condensible gases in the IC/sub 4/ loop and IC/sub 4/ in the brine stream. The second test phase was to provide a longer term run at nearly fixed operating conditions in order to evaluate plant performance and identify operating cost data for the pilot plant. During these tests the total accumulated run time on major system components exceeded 1180 hours with 777 hours on the turbine prime mover. Direct contact heat exchanger performance exceeded the design prediction.
Date: October 1, 1981
Creator: Hlinak, A.; Lee, T.; Loback, J.; Nichols, K.; Olander, R.; Oshmyansky, S. et al.
Partner: UNT Libraries Government Documents Department

Accelerating the loop expansion

Description: This thesis introduces a new non-perturbative technique into quantum field theory. To illustrate the method, I analyze the much-studied phi/sup 4/ theory in two dimensions. As a prelude, I first show that the Hartree approximation is easy to obtain from the calculation of the one-loop effective potential by a simple modification of the propagator that does not affect the perturbative renormalization procedure. A further modification then susggests itself, which has the same nice property, and which automatically yields a convex effective potential. I then show that both of these modifications extend naturally to higher orders in the derivative expansion of the effective action and to higher orders in the loop-expansion. The net effect is to re-sum the perturbation series for the effective action as a systematic ''accelerated'' non-perturbative expansion. Each term in the accelerated expansion corresponds to an infinite number of terms in the original series. Each term can be computed explicitly, albeit numerically. Many numerical graphs of the various approximations to the first two terms in the derivative expansion are given. I discuss the reliability of the results and the problem of spontaneous symmetry-breaking, as well as some potential applications to more interesting field theories. 40 refs.
Date: July 29, 1986
Creator: Ingermanson, R.
Partner: UNT Libraries Government Documents Department

Acoustic and electrical properties of Mexican geothermal rock samples

Description: Acoustic compressional and shear-wave velocities have been measured on a suite of ten sandstone samples obtained from wells in the Cerro Prieto geothermal field and on two rock samples from other Mexican geothermal fields. The samples were tested in both their dry and fully brine-saturated states at uniaxial stresses to 15 MPa. Electrical resistivities and associated phase angles have been measured on the same core samples as a function of frequency in the range 10 Hz to 10/sup 5/ Hz under drained conditions at hydrostatic confining stresses to 10 MPa. The electrical properties were measured on samples tested in their fully saturated state, using brines of two different concentrations.
Date: December 1, 1984
Creator: Contreras, E.A. & King, M.S.
Partner: UNT Libraries Government Documents Department

Advanced concepts for acceleration

Description: Selected examples of advanced accelerator concepts are reviewed. Such plasma accelerators as plasma beat wave accelerator, plasma wake field accelerator, and plasma grating accelerator are discussed particularly as examples of concepts for accelerating relativistic electrons or positrons. Also covered are the pulsed electron-beam, pulsed laser accelerator, inverse Cherenkov accelerator, inverse free-electron laser, switched radial-line accelerators, and two-beam accelerator. Advanced concepts for ion acceleration discussed include the electron ring accelerator, excitation of waves on intense electron beams, and two-wave combinations. (LEW)
Date: July 1, 1986
Creator: Keefe, D.
Partner: UNT Libraries Government Documents Department

AGS preinjector improvement

Description: In 1984, a polarized H/sup -/ source was installed to permit the acceleration of polarized protons in the AGS, using a low current, 750 keV RFQ Linear Accelerator as the preinjector. This RFQ was designed by LANL and has proved to be quite satisfactory and reliable. In order to improve the reliability and simplify maintenance of the overall AGS operations, it has been decided to replace one of the two 750 keV Cockcroft-Waltons (C-W) with an RFQ. The design of a new high current RFQ has been carried out by LBL and is also being constructed there. This paper describes the preinjector improvement project, centered around that RFQ, which is underway at BNL.
Date: January 1, 1987
Creator: Alessi, J.G.; Brennan, J.M.; Brown, H.N.; Brodowski, J.; Gough, R.; Kponou, A. et al.
Partner: UNT Libraries Government Documents Department

Analysis and interpretation of a high density tandem negative ion source

Description: In the last few years the development of tandem-discharge hydrogen-negative-ion-source systems has proceeded along both experimental and theoretical lines. To some extent these developments have proceeded independently, either the available theoretical model was inadequate to account for a specific geometrical configuration, or the experimental data was not sufficient to provide adequate input parameters for calculation. In the tandem system described here the electron temperature, electron density, and other relevant parameters have been obtained for a high-density system whose electron densities range up to 3 - 5 x 10/sup 12/ electrons cm/sup -3/. The model calculation for the atomic processes has been extended to include both electron density and electron temperature spatial variations through the second chamber. These spatial variations are essential for an adequate interpretation of tandem systems where steep density gradients may occur beyond the magnetic filter region. In this paper we shall combine the experimental density data with the new spatially dependent atomic model for the purpose of attempting a correlation of the observed and calculated current densities. 9 refs., 8 figs., 3 tabs.
Date: October 22, 1986
Creator: Hiskes, J.R.; Lietzke, A.F. & Hauck, C.
Partner: UNT Libraries Government Documents Department

Analysis of an induction linac driver system for inertial fusion

Description: A linear induction accelerator that produces a beam of energetic (5 to 20 GeV) heavy (130 to 210 amu) ions is a prime candidate as a driver for inertial fusion. Continuing developments in sources for ions with charge state greater than unity allow a potentially large reduction in the driver cost and an increase in the driver efficiency. The use of high undepressed tunes (sigma/sub 0/ approx. = 85/sup 0/) and low depressed tunes (sigma approx. = 8.5/sup 0/) also contributes to a potentially large reduction in the driver cost. The efficiency and cost of the induction linac system are discussed as a function of output energy and pulse repetition frequency for several ion masses and charge states. The cost optimization code LIACEP, including accelerating module alternatives, transport modules, and scaling laws, is presented. Items with large cost-leverage are identified as a guide to future research activities and development of technology that can yield substantial reductions in the accelerator system cost and improvement in the accelerator system efficiency. Finally, a cost-effective strategy using heavy ion induction linacs in a development scenario for inertial fusion is presented. 34 refs., 6 figs., 7 tabs.
Date: July 1, 1987
Creator: Hovingh, J.; Brady, V.O.; Faltens, A.; Keefe, D. & Lee, E.P.
Partner: UNT Libraries Government Documents Department

Analysis of flow data from several Baca wells

Description: Analyses are presented of the downhole pressure buildup data for wells located in the Redondo Creek area of the Baca Geothermal Field. The downhole drilling information and pressure/temperature surveys are first interpreted to locate zones at which fluid enters the wellbore from the fractured formation and to estimate the initial reservoir temperature and pressure in these zones. Interpretation of the buildup data for each well considers wellbore effects, the CO{sub 2} content of the fluid and differentiates between the single-phase and two-phase portions of the data. Different straight-line approximations to the two portions of the data on the Horner plot for a flow test yield corresponding estimates for the single and two-phase mobilities. Estimates for the formation kh are made for the wells.
Date: December 1, 1981
Creator: Riney, T.D. & Garg, S.K.
Partner: UNT Libraries Government Documents Department

Analysis of thermally induced permeability enhancement in geothermal injection wells

Description: Reinjection of spent geothermal brine is a common means of disposing of geothermal effluents and maintaining reservoir pressures. Contrary to the predictions of two-fluid models (two-viscosity) of nonisothermal injection, an increase of injectivity, with continued injection, is often observed. Injectivity enhancement and thermally-affected pressure transients are particularly apparent in short-term injection tests at the Los Azufres Geothermal Field, Mexico. During an injection test, it is not uncommon to observe that after an initial pressure increase, the pressure decreases with time. As this typically occurs far below the pressure at which hydraulic fracturing is expected, some other mechanism for increasing the near-bore permeability must explain the observed behavior. This paper focuses on calculating the magnitude of the nearbore permeability changes observed in several nonisothermal injection tests conducted at the Los Azufres Geothermal Field.
Date: February 1, 1987
Creator: Benson, S.M.; Daggett, J.S.; Iglesias, E.; Arellano, V. & Ortiz-Ramirez, J.
Partner: UNT Libraries Government Documents Department

Analysis of well test data from selected intervals in Leuggern deep borehole

Description: Applicability of the PTST technique was verified by conducting a sensitivity study to the various parameters. The study showed that for ranges of skin parameters the true formation permeability was still successfully estimated using the PTST analysis technique. The analysis technique was then applied to field data from the deep borehole in Leuggern, Northern Switzerland. The analysis indicated that the formation permeability may be as much as one order of magnitude larger than the value based on no-skin analysis. Swabbing data from the Leuggern deep borehole were also analyzed assuming that they are constant pressure tests. The analysis of the swabbing data indicates that the formation transmissivity is as much as 20 times larger than the previously obtained value. This study is part of an investigation of the feasibility of geologic isolation of nuclear wastes being carried out by the US Department of Energy and the National Cooperative for the Storage of Radioactive Waste of Switzerland.
Date: July 1, 1990
Creator: Karasaki, K. (Lawrence Berkeley Lab., CA (USA))
Partner: UNT Libraries Government Documents Department

Angular distribution and atomic effects in condensed phase photoelectron spectroscopy

Description: A general concept of condensed phase photoelectron spectroscopy is that angular distribution and atomic effects in the photoemission intensity are determined by different mechanisms, the former being determined largely by ordering phenomena such as crystal momentum conservation and photoelectron diffraction while the latter are manifested in the total (angle-integrated) cross section. In this work, the physics of the photoemission process is investigated in several very different experiments to elucidate the mechanisms of, and correlation between, atomic and angular distribution effects. Theoretical models are discussed and the connection betweeen the two effects is clearly established. The remainder of this thesis, which describes experiments utilizing both angle-resolved and angle-integrated photoemission in conjunction with synchrotron radiation in the energy range 6 eV less than or equal to h ..nu.. less than or equal to 360 eV and laboratory sources, is divided into three parts.
Date: November 1, 1981
Creator: Davis, R.F.
Partner: UNT Libraries Government Documents Department

Annealing of interstitial loops in arsenic implanted silicon

Description: The annealing effect of different gas ambient (N/sub 2/ or O/sub 2/) on high dose (5 x 10/sup 15/) As-ion-implanted Si wafer has been investigated by using transmission electronic microscope. A two-layer defect structure is observed. The lower layer defects are interstitial type and attributed to the amorphous island below original crystalline-amorphous interface. The upper layer loops are As precipitation in the form of stacking fault. By comparing the growth/shrinkage rate of interstitial loops during neutral and oxygen annealing, it is proved that interstitial silicons are injected into bulk silicon during oxidation.
Date: May 1, 1983
Creator: Wu, N.R.; Ling, P.; Sadana, D.K.; Washburn, J. & Current, M.I.
Partner: UNT Libraries Government Documents Department

Anomalies in quantum field theory and differential geometry

Description: Anomalies in field theory appeared first in perturbative computations involving Feynman diagrams. It is only recently that differential geometric techniques have been used to obtain the form of gauge and gravitational anomalies in a direct and simple way. This is possible because of the topological nature of the anomaly. In the first chapter of this thesis the gauged Wess-Zumino action is constructed by differential geometry methods. After reviewing the relevant techniques, an expression for the action valid in any (even) number of space-time dimensions is obtained. This expression is compared with Witten's result in four dimensions. The link between topology and the anomaly is provided by the appropriate index theorem. The index density is a supersymmetric invariant polynomial from which the anomaly and other related objects can be obtained through the use of the ''descent equations.'' A new proof of the Atiyah-Singer index theorem for the Dirac operator is presented. This proof is based on the use of a WKB approximation to evaluate the supertrace of the kernel for a supersymmetric hamiltonian. The necessary WKB techniques are developed and mechanical systems with bosonic and fermionic degrees of freedom are discussed.
Date: April 1, 1986
Creator: Manes, J.L.
Partner: UNT Libraries Government Documents Department

Aperture studies with Patricia and Racetrack on simple lattices containing SSC dipoles

Description: The PATRICIA and RACETRACK particle tracking programs have been compared by tracking on a simple lattice. The dynamic aperture was found to decrease as the number of passes through the lattice per run increased from 20 to approx. 300, and it remained constant for longer runs. The dynamic apertures found by the two programs are consistent. The dependence of the dynamic aperture on horizontal tune near a decapole resonance was investigated. RACETRACK and PATRICIA showed decreases in the aperture on opposite sides of the resonance. A second set of studies was made with PATRICIA in which the dynamic apertures of lattices consisting of cells of the types used for the Reference Designs Study were determined when random multipole errors of the dipoles were included. The dependence of aperture on the number of cells in the lattice was determined. Finally, a comparison of magnet types suggested for the SSC was made by determining the aperture of lattices containing these magnets.
Date: June 23, 1984
Creator: Dell, G.F.; Leemann, B. & Willeke, F.
Partner: UNT Libraries Government Documents Department

Apiary B Factory lattice design

Description: The Apiary B Factory is a proposed high-intensity electron-positron collider. This paper will present the lattice design for this facility, which envisions two rings with unequal energies in the PEP tunnel. The design has many interesting optical and geometrical features due to the needs to conform to the existing tunnel, and to achieve the necessary emittances, damping times and vacuum. Existing hardware is used to a maximum extent. 8 figs. 1 tab.
Date: April 1, 1991
Creator: Donald, M.H.R. (Stanford Linear Accelerator Center, Menlo Park, CA (USA)) & Garren, A.A. (Lawrence Berkeley Lab., CA (USA))
Partner: UNT Libraries Government Documents Department

Apiary B-Factory separation scheme

Description: A magnetic beam-separation scheme for an asymmetric-energy B-Factory based on the SLAC electron-positron collider PEP is described that has the following properties: the beams collide head-on and are separated magnetically with sufficient clearance at the parasitic crossing points and at the septum, the magnets have large beam-stay-clear apertures, synchrotron radiation produces low detector backgrounds and acceptable heat loads, and the peak {beta}-function values and contributions to the chromaticities in the IR quadrupoles are moderate. 8 figs., 2 tabs.
Date: April 1, 1991
Creator: Garren, A. (Lawrence Berkeley Lab., CA (USA)) & Sullivan, M. (Stanford Linear Accelerator Center, Menlo Park, CA (USA))
Partner: UNT Libraries Government Documents Department