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Use of molybdenum ion source electrodes at RTNS-II

Description: Reports are reported for an ongoing effort to optimize D+ beam production by the MATS-III ion source used at RTNS-II. The three seven-aperture electrodes, originally consisting of water-cooled copper, have now been tested using uncooled molybdenum and with water cooling on the second (decel) electrode only. Details of the change, the results of the testing, and the benefits in operation, performance and cost are given.
Date: September 29, 1986
Creator: Massoletti, D.J.; Harter, G.A. & Heikkinen, D.W.
Partner: UNT Libraries Government Documents Department
open access

Structure functions: Their status and implications

Description: I discuss the current status of structure functions. Attention is given to the uncertainties in them and the implications of these uncertainties for experimental predictions. I indicate which experiments are capable of removing these uncertainties. 17 refs., 17 figs., 1 tab.
Date: September 29, 1988
Creator: Hinchliffe, I.
Partner: UNT Libraries Government Documents Department
open access

Top quark and light Higgs scalar mass bounds in no-scale supergravity

Description: No-scale supergravity theories with the minimal low-energy particle content are shown to become untenable for a top quark mass m/sub T/ much less than 40 GeV. For m/sub T/ < 55 GeV, a stringent upper bound operates on the mass of the lowest-lying Higgs scalar. Further, the Higgs pseudoscalar is constrained to be nearly a quarter as massive as the gluino.
Date: August 29, 1986
Creator: Roy, P.
Partner: UNT Libraries Government Documents Department
open access

Oxide cathode lifetime improvements at RTNS-II

Description: Results are reported for an ongoing effort to optimize D/sup +/ beam production by the MATS-III ion source used at the RTNS-II. The oxide cathode assembly originally designed for lower power operation has been modified and redesigned for higher electron current yield, longer life and serviceability. A factor of 2.5 has been gained in cathode lifetime due to these changes. The details of the changes and results and benefits in operation and performance are given. In addition, the technique used … more
Date: September 29, 1986
Creator: Massoletti, D.J.
Partner: UNT Libraries Government Documents Department
open access

Overview of radioactive waste management

Description: The question of what to do with radioactive wastes is discussed. The need to resolve this issue promptly is pointed out. Two significant events which have occurred during the Carter administration are discussed. An Interagency Review Group (IRG) on waste management was formed to formulate recommendations leading to the establishment of a National policy for managing radioactive wastes. The technical findings in the IRG report are listed. The author points out some issues not addressed by the re… more
Date: May 29, 1980
Creator: Ritter, G.L.
Partner: UNT Libraries Government Documents Department
open access

Applications of small computers for systems control on the Tandem Mirror Experiment-Upgrade

Description: Desktop computers operating into a CAMAC-based interface are used to control and monitor the operation of the various subsystems on the Tandem Mirror Experiment-Upgrade (TMX-U) at Lawrence Livermore National Laboratory (LLNL). These systems include: shot sequencer/master timing, neutral beam control (four consoles), magnet power system control, ion-cyclotron resonant heating (ICRH) control, thermocouple monitoring, getter system control, gas fueling system control, and electron-cyclotron resona… more
Date: November 29, 1983
Creator: Bork, R. G.; Kane, R. J. & Moore, T. L.
Partner: UNT Libraries Government Documents Department
open access

Control of beam dynamics in high energy induction linacs

Description: The Advent of laser-ion-guiding in the Advanced test Accelerator along with the development of accelerator cavities optimized with respect to beam breakup coupling impedence now make it possible to consider a new class of high current, high emergy linear induction accelerators. The control of the beam breakup and other instabilities by laser guiding and by various magnetic focusing schemes will be discussed along with the scaling laws for the design of such machines to minimize the growth of th… more
Date: July 29, 1986
Creator: Caporaso, G.J.
Partner: UNT Libraries Government Documents Department
open access

Does the photino decay

Description: The stability of the lightest superpartner is a crucial aspect of many experimental searches for supersymmetry and of supersymmetric dark matter candidates. It is shown that R parity may occur in operators of dimension four or less as an accidental consequence of an exact Z/sub N/ symmetry. In this case the lightest superpartner can decay via higher dimension operators. The lifetime depends on the scale of the new physics responsible for the non-renormalizable operators; it could be anywhere in… more
Date: August 29, 1986
Creator: Hall, L.J.
Partner: UNT Libraries Government Documents Department
open access

Localized corrosion of steels in geothermal steam/brine mixtures

Description: Coupons of eight different carbon and chrome-moly alloy steels were exposed to high temperature, high salinity wellhead brine flow at a geothermal well in the Salton Sea Geothermal Field for periods of up to six months. The corrosion rate and corrosion attack morphology of each coupon was determined. Exposure time was a test variable and ranged from one month to six months. Test results indicate that carbon steels generally suffer high corrosion rates and are susceptible to severe localized att… more
Date: May 29, 1980
Creator: McCright, R. D.; Frey, W. F. & Tardiff, G. E.
Partner: UNT Libraries Government Documents Department
open access

TMX tandem-mirror experiments and thermal-barrier theoretical studies

Description: This paper describes recent analysis of energy confinement in the Tandem Mirror Experiment (TMX). TMX data also indicates that warm plasma limits the amplitude of the anisotropy driven Alfven ion cyclotron (AIC) mode. Theoretical calculations show strong AIC stabilization with off-normal beam injection as planned in TMX-U and MFTF-B. This paper reports results of theoretical analysis of hot electrons in thermal barriers including electron heating calculations by Monte Carlo and Fokker-Planck co… more
Date: July 29, 1982
Creator: Simonen, T. C.; Baldwin, D. E. & Allen, S. L.
Partner: UNT Libraries Government Documents Department
open access

Application of heavy-light methods to B meson physics

Description: The heavy-light method is applied to the study of the B meson spectrum, the pseudoscalar decay constant f{sub B}, the mixing (B) parameter, and exclusive semileptonic B meson decays. Preliminary results are discussed for f{sub B} and the B parameter at {beta} = 5.7 and {kappa} = 0.165 on a 12{sup 3} {times} 24 lattice and at {beta} = 5.9 and {kappa} = 0.158 on a 16{sup 3} {times} 32 lattice. 9 refs., 2 figs., 2 tabs.
Date: December 29, 1989
Creator: Eichten, E.; Hockney, G. & Thacker, H.B.
Partner: UNT Libraries Government Documents Department
open access

TMX tandem-mirror experiments and thermal-barrier theoretical studies

Description: This paper describes recent analysis of energy confinement in the Tandem Mirror Experiment (TMX). TMX data also indicates that warm plasma limits the amplitude of the anisotropy driven Alfven ion cyclotron (AIC) mode. Theoretical calculations show strong AIC stabilization with off-normal beam injection as planned in TMX-U and MFTF-B. This paper reports results of theoretical analysis of hot electrons in thermal barriers including electron heating calculations by Monte Carlo and Fokker-Planck co… more
Date: July 29, 1982
Creator: Simonen, T. C.; Baldwin, D. E. & Allen, S. L.
Partner: UNT Libraries Government Documents Department
open access

Reservoir response to tidal and barometric effects

Description: Solid earth tidal strain and surface loading due to fluctuations in barometric pressure have the effect, although extremely minute, of dilating or contracting the effective pore volume in a porous reservoir. If a well intersects the formation, the change in pore pressure can be measured with sensitive quartz pressure gauges. Mathematical models of the relevant fluid dynamics of the well-reservoir system have been generated and tested against conventional well pumping results or core data at the… more
Date: May 29, 1980
Creator: Hanson, J.M.
Partner: UNT Libraries Government Documents Department
open access

Ion microstability in tandem mirrors

Description: The formalism describing ion-cyclotron modes in mirror traps will be developed. Emphasis will be placed on the effects of finite axial boundaries on the normal modes of the system. Wave properties are a composite picture of: positive energy waves (plasma oscillation, shear Alfven and drift waves), negative energy waves (ion Bernstein waves in a loss-cone media), positive dissipation (electron Landau damping, outgoing waves), and negative dissipation (ion cyclotron damping in a loss-cone and ani… more
Date: August 29, 1983
Creator: Pearlstein, L.D.
Partner: UNT Libraries Government Documents Department
open access

Mirror research: status and prospects

Description: The tandem mirror program has evolved considerably in the last decade. Of significance is the viable reactor concept embodied in the MARS design. An aggressive experimental program culminating in the operation of MFTF-B in late 1986, will provide a firm basis for refining the MARS design as necessary for constructing a reactor prototype in the 1990s.
Date: November 29, 1983
Creator: Baldwin, D.E.
Partner: UNT Libraries Government Documents Department
open access

LMFBR fuel component costs

Description: A significant portion of the cost of fabricating LMFBR fuels is in the non-fuel components such as fuel pin cladding, fuel assembly ducts and end fittings. The contribution of these to fuel fabrication costs, based on FFTF experience and extrapolated to large LMFBR fuel loadings, is discussed. The extrapolation considers the expected effects of LMFBR development programs in progress on non-fuel component costs.
Date: October 29, 1981
Creator: Epperson, E.M.; Borisch, R.R. & Rice, L.H.
Partner: UNT Libraries Government Documents Department
open access

Progress toward identification of gluonic states

Description: Progress in the last two years toward identification of gluonic states is reviewed. Discovery of additional pseudoscalars tends to confirm the glueball interpretation of iota(1460). A variety of evidence indicates new physics in the J = 1 channel in the E mass region. 65 refs., 1 tab.
Date: May 29, 1987
Creator: Chanowitz, Michael S.
Partner: UNT Libraries Government Documents Department
open access

[Newspaper article: AIDS, The State of the Science]

Description: A special report from the Dallas Morning News defining, describing, and providing the history of AIDS.
Date: June 29, 1987
Creator: The Dallas Morning News
Partner: UNT Libraries Special Collections
open access

Use of the (t,p) reaction for in-beam spectroscopy studies

Description: Triton induced reactions, such as the (t,p) reaction, can be used for in-beam gamma-ray and conversion-electron studies of nuclei that are somewhat neutron rich. We have developed systems for both conversion-electron and gamma-ray spectroscopy in coincidence with the outgoing energetic proton to identify the (t,p) reaction channel. Data from the /sup 142/Nd(t,p..gamma..) reaction illustrate several of the characteristics of this reaction for studying nuclear structure. Preliminary results from … more
Date: May 29, 1986
Creator: Henry, E.A.
Partner: UNT Libraries Government Documents Department
open access

Tools and methods for implementing the control systems on the Mirror Fusion Test Facility

Description: Installation of the major hardware subsystems for MFTF is nearing completion. These subsystems include the Fusion Chamber System, the eighty KV Neutral Beam System, the Superconducting Magnet System, and the Personnel Safety System. The Local Controls group has undertaken a uniform aproach to implementing the control systems for all of these hardware subsystems. This approach has two major aspects: (1) to provide a stand-alone computer control system with a remote, portable terminal so that com… more
Date: September 29, 1981
Creator: Minor, E. G. & Labiak, W. G.
Partner: UNT Libraries Government Documents Department
open access

Debugging in a multi-processor environment

Description: The Supervisory Control and Diagnostic System (SCDS) for the Mirror Fusion Test Facility (MFTF) consists of nine 32-bit minicomputers arranged in a tightly coupled distributed computer system utilizing a share memory as the data exchange medium. Debugging of more than one program in the multi-processor environment is a difficult process. This paper describes what new tools were developed and how the testing of software is performed in the SCDS for the MFTF project.
Date: September 29, 1981
Creator: Spann, J.M.
Partner: UNT Libraries Government Documents Department
open access

Layered granule chute flow near the angle of repose

Description: A natural, two-layered gravity flow of sand can be obtained on chutes inclined at angles slightly above the angle of repose of the sand. The top-surface layer is free-flowing, is thin, and moves rapidly at supercritical velocity. The velocity depends mainly on the character of the sand and the chute inclination angle. The bottom layer is thick and moves more slowly, with the flow controlled by adjustable weirs at the chute exit. The velocity profile in the thick bottom layer is curved; as much … more
Date: March 29, 1985
Creator: Pitts, J.H. & Walton, O.R.
Partner: UNT Libraries Government Documents Department
open access

Three-dimensional equilibrium in quadrupole symmetric tandem mirrors in the paraxial limit (reduced MHD)

Description: Equilibrium in quadrupole symmetric mirrors is fully three dimensional; however, because axial scale lengths are long compared with radial scale lengths (equivalently weak curvature) it is possible to reduce the complexity of the equations by expanding in the appropriate smallness parameter. Such a procedure leads to set of reduced MHD equations. The general theory will be presented, numerical results discussed, modifications due to finite Larmor radius will be added, and an analytic solution f… more
Date: August 29, 1983
Creator: Pearlstein, L.D.
Partner: UNT Libraries Government Documents Department
open access

The LLNL CR-39 personnel neutron dosimeter

Description: We developed a personnel neutron dosimetry system based on the electrochemical etching of CR-39 plastic at elevated temperatures. The doses obtained using this dosimeter system are more accurate than those obtained using other dosimetry systems, especially when varied neutron spectra are encountered. This CR-39 dosimetry system does not have the severe energy dependence that exists with albedo neutron dosimeters or the fading and reading problems encountered with NTA film. 3 refs., 4 figs.
Date: September 29, 1987
Creator: Hankins, D.E.; Homann, S. & Westermark, J.
Partner: UNT Libraries Government Documents Department
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