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Access control system for ISABELLE (open access)

Access control system for ISABELLE

An access system based on the one now in operation at the CERN ISR is recommended. Access doors would presumably be located at the entrances to the utility tunnels connecting the support buildings with the ring. Persons requesting access would insert an identity card into a scanner to activate the system. The request would be autologged, the keybank adjacent to the door would be unlocked and ISABELLE operations would be notified. The operator would then select the door, activating a TV-audio link. The person requesting entry would draw a key from the bank, show it and his film badge to the operator who would enable the door release.
Date: August 17, 1977
Creator: Potter, K. & Littenberg, L.
System: The UNT Digital Library
Prototype photon position monitors for undulator beams at the Advanced Light Source (open access)

Prototype photon position monitors for undulator beams at the Advanced Light Source

Design criteria are described, and test results are presented, for prototype ALS undulator beam position monitors. The design is based on monitors presently in use at NSLS, with modifications to account for the widely varying and large K values of the undulators to be installed at the ALS. In particular, we have modified the design to simplify the thermal engineering and we have explored techniques to suppress the response of the monitors to soft photons, so that the beam position can be determined by measuring the higher energy photons which are better collimated. 4 refs., 8 figs.
Date: October 17, 1990
Creator: Warwick, T.; Shu, D. (Lawrence Berkeley Lab., CA (United States)); Rodricks, B. (Argonne National Lab., IL (United States)) & Johnson, E.D. (Brookhaven National Lab., Upton, NY (United States))
System: The UNT Digital Library
Optical components for the Nova laser (open access)

Optical components for the Nova laser

In addition to its other characteristics, the Nova Laser Fusion facility may well be the largest precision optical project ever undertaken. Moreover, during the course of construction, concurrent research and development has been successfully conducted, and has resulted in significant advances in various technical areas, including manufacturing efficiency. Although assembly of the first two beams of Nova is just commencing, the optical production, including construction of the special facilities required for many of the components, has been underway for over three years, and many phases of the optical manufacturing program for the first 10 beams will be completed within the next two years. On the other hand, new requirements for second and third harmonic generation have created the need to initiate new research and development. This work has been accomplished through the enormous cooperation DOE/LLNL has received from commercial industry on this project. In many cases, industry, where much of the optical component research and development and virtually all of the manufacturing is being done, has made substantial investment of its own funds in facilities, equipment, and research and development, in addition to those supplied by DOE/LLNL.
Date: May 17, 1982
Creator: Wallerstein, E.P.; Baker, P.C. & Brown, N.J.
System: The UNT Digital Library
Auger study of surface carbon and oxygen on thorium following ion bombardment (open access)

Auger study of surface carbon and oxygen on thorium following ion bombardment

The composition of a thorium metal surface has been monitored using Auger electron spectroscopy following Ar/sup +/ bombardment at different temperatures. After extended Ar/sup +/ bombardment, enough contaminated overlayers were removed to expose a surface region containing only thorium, bulk impurities, and imbedded argon. The main impurities, carbon and oxygen, differed in their behavior when the sample was annealed following bombardment. The amount of surface carbon either increased or remained constant during annealing depending upon the temperature of the sample during bombardment. The amount of surface oxygen decreased rapidly when the sample was heated above 500/sup 0/C regardless of the sample temperature during bombardment. These experiments indicate that preparation of clean, annealed thorium surfaces requires ion bombardment at temperatures > or = 400/sup 0/C.
Date: November 17, 1977
Creator: Bastasz, R. & Colmenares, C.
System: The UNT Digital Library
Models for Type I supernovae (open access)

Models for Type I supernovae

Two rather disjoint scenarios for Type I supernovae are presented. One is based upon mass accretion by a white dwarf in a binary system. The second involves a star having some 8 to 10 times the mass of the sun which may or may not be a solitary star. Despite the apparent dissimilarities in the models it may be that each occurs to some extent in nature for they both share the possibility of producing substantial quantities of /sup 56/Ni and explosions in stars devoid of hydrogen envelopes. These are believed to be two properties that must be shared by any viable Type I model.
Date: June 17, 1980
Creator: Woosley, S. E.; Weaver, T. A. & Taam, R. E.
System: The UNT Digital Library
A high-fluence fusion neutron source (open access)

A high-fluence fusion neutron source

A conceptual design of a D-T fusion facility for continuous production of 14-MeV neutron wall loading from 5 to 10 MW/m/sup 2/ at the plasma surface is presented. In this design, D-T neutrons are produced in a linear, two-component plasma formed by neutral beam irradiation of a fully ionized warm plasma target. The beam energy, which is deposited in the center, is transferred to the warm plasma mainly by electron drag and is conducted along the target plasma column to end regions where it is absorbed in neutral gas at high pressure. The target plasma is operated in a regime where electron thermal conduction along the column is the controlling energy-loss process. The loss rate is minimized by adjusting the diameter and length of the plasma column. A substantial gradient in T/sub e/ along the column results in recombination of the plasma to gas in the end-regions before impact on the end walls. The resultant hot gas is cooled by contact with large-area heat exchangers. In this way, the large steady-state heat load from the injected neutral beams is diffused and removed at tolerable heat flux levels. The reacting plasma is essentially an extrapolation of the 2XIIB high-..beta.. plasma to …
Date: February 17, 1988
Creator: Coensgen, F. H.; Casper, T. A.; Correll, D. L.; Damm, C. C.; Futch, A. H.; Logan, B. G. et al.
System: The UNT Digital Library
Stimulated Raman scatter in laser fusion target chambers (open access)

Stimulated Raman scatter in laser fusion target chambers

The target chamber of a laser fusion reactor will contain small amounts of background gases. As the beam is focused, it ionizes the gas and Raman scattering is induced. Density limits on the background gas are found in order that the laser beam will not become appreciably decollimated. It is found that laser bandwidth efficiently decreases the scattering effect.
Date: October 17, 1977
Creator: Thomson, J.J.
System: The UNT Digital Library
Control of radioactive material transport in sodium-cooled reactors (open access)

Control of radioactive material transport in sodium-cooled reactors

The Radioactivity Control Technology (RCT) program was established by the Department of Energy to develop and demonstrate methods to control radionuclide transport to ex-core regions of sodium-cooled reactors. This radioactive material is contained within the reactor heat transport system with any release to the environment well below limits established by regulations. However, maintenance, repair, decontamination, and disposal operations potentially expose plant workers to radiation fields arising from radionuclides transported to primary system components. This paper deals with radioactive material generated and transported during steady-state operation, which remains after /sup 24/Na decay. Potential release of radioactivity during postulated accident conditions is not discussed. The control methods for radionuclide transport, with emphasis on new information obtained since the last Environmental Control Symposium, are described. Development of control methods is an achievable goal.
Date: March 17, 1980
Creator: Brehm, W. F.
System: The UNT Digital Library
Radioactive gas and hydrogen removal after a LOCE at the LOFT Facility (open access)

Radioactive gas and hydrogen removal after a LOCE at the LOFT Facility

The use of a silver-zeolite halogen adsorber placed in series with a hydrogen catalytic recombiner and a cryogenic noble gas adsorber assembly constitutes a waste gas processing system (WGPS) capable of handling hydrogen and fission product gases following a Loss-of-Coolant Experiment (LOCE). This paper describes: the types and quantities of gases expected to be found at the facility after a failed-fuel LOCE; the purpose of the WGPS; and the general configuration and expected decontamination factors associated with the LOFT WGPS.
Date: December 17, 1979
Creator: McCormick-Barger, J.W. & Sumpter, K.C.
System: The UNT Digital Library
Methodology for assessing the potential impact on air quality resulting from geothermal resource development in the Imperial Valley (open access)

Methodology for assessing the potential impact on air quality resulting from geothermal resource development in the Imperial Valley

Methodology in use in the Imperial Valley for assessing the potential impact on air quality that may result from the development of geothermal resources is discussed. The installation of a network of air quality stations for characterizing the air quality and atmospheric transport properties in the valley prior to development is discussed. Analyses of geothermal fluids for various gases are performed to evaluate the potential emission rates from future geothermal power plants. The principal pollutant of concern is H/sub 2/S because of its noxious odor and potential release rate. These estimated source emission rates and the appropriate meteorological measurements are used as input to a three-dimensional, atmospheric transport code to estimate the potential changes in air quality that result from various scenarios for development of geothermal power.
Date: October 17, 1977
Creator: Gudiksen, P. H.; Axelrod, M. C.; Ermak, D. L.; Lamson, K. C. & Lange, R.
System: The UNT Digital Library
Mechanical design for TMX injector system (open access)

Mechanical design for TMX injector system

The injector system for the Tandem Mirror Experiment (TMX) contains the components required to create and maintain a high-temperature, high-density plasma. These components include a streaming-plasma gun in each of the plug tanks to form the target-plasma, 24 neutral-beam source modules for injecting neutral deuterium atoms to heat and replace losses from the plasma, and a gas box system that applies a streaming cold gas to the plasma to stabilize it. This paper discusses the mechanical design problems and solutions for this injector system.
Date: October 17, 1977
Creator: Calderon, M.O.; Chen, F.F.K. & Denhoy, B.S.
System: The UNT Digital Library
Effect of light-delignification on mechanical, hydrophobic, and thermal properties of high-strength molded fiber materials (open access)

Effect of light-delignification on mechanical, hydrophobic, and thermal properties of high-strength molded fiber materials

This article discusses the development of a high-strength molded fiber material using pulp fibers, which coudl be a good substitute for plastic and solid wood materials.
Date: July 20, 2017
Creator: Wang, Quanliang; Xiao, Shengling; Shi, Sheldon Q. & Cai, Liping
System: The UNT Digital Library
Early Admission to College for Bright Students (open access)

Early Admission to College for Bright Students

Article discussing the early admission to college programs, including the Texas Academy of Mathematics and Science.
Date: May 17, 1989
Creator: Cromer, Alan
System: The UNT Digital Library
Monopole strength as a probe of nuclear shape mixing (open access)

Monopole strength as a probe of nuclear shape mixing

The monopole strength, MS, within a single set of nuclear shape excitations is compared with the MS between different shapes. After misconceptions are pointed out concerning the spin dependence of B(E2) values, MS properties are juxtaposed with gamma-ray and beta-decay properties of /sup 70/Se, /sup 96/Zr, /sup 102/Pd, and the N = 60 isotones to illustrate the utility of combined investigations and evidence is given for the observation of a two-phonon octupole multiplet. Finally, consideration is given to the dominance of the /sup 3/S/sub 1/ force in producing deformation in the N > 50 1g nuclei. 23 refs., 4 figs.
Date: August 17, 1987
Creator: Meyer, R.A.
System: The UNT Digital Library
Hadronic production of J/sup PC/ = 2/sup + +/ glueballs (open access)

Hadronic production of J/sup PC/ = 2/sup + +/ glueballs

An OZI suppressed channel with variable mass, namely the reaction ..pi../sup -/p ..-->.. phi phi n, has been used as a filter which allows resonating gluons or glueballs to pass, while strongly rejecting conventional quark-built hadronic states. The breakdown of the OZI suppression signals a glueball. Glueball mass and particle width estimates are discussed. Reasons why g/sub T/'s have not been seen in other channels, particularly the decay of J/psi, are considered. 34 refs., 9 figs. (LEW)
Date: March 17, 1986
Creator: Lindenbaum, S. J.
System: The UNT Digital Library
Liquid nitrogen cooled liners for 2XIIB (open access)

Liquid nitrogen cooled liners for 2XIIB

Liquid-nitrogen-cooled liners have been installed in the neutral-beam source tanks of 2XIIB. The installation has resulted in improvements in vacuum pumping, although testing is not complete. The liners are stainless-steel-flooded-type liners, using spot-welded-and-inflation construction. The natural-convection flow system must keep the liners cold during the high heat loads imposed during Ti gettering.
Date: October 17, 1977
Creator: Atkinson, D.P. & Calderon, M.O.
System: The UNT Digital Library
Comparison of theory and simulations with recent laser plasma experiments (open access)

Comparison of theory and simulations with recent laser plasma experiments

In the past few months, detailed experimental data have become available on laser light absorption versus angle, plasma density profiles near the critical surface, and stimulated scattering processes. In the light of these experiments, it seems timely to reassess our theoretical understanding of these phenomena. A quantitative comparison of the data with current results of plasma simulations and theory is presented and the areas where further theoretical effort is called for are pointed out. Three recent experiments done at Livermore are compared with the latest theoretical and simulation results on laser-plasma interactions. The analysis covers the following areas: (1) theory of resonance absorption on a rippled critical surface, compared with an experiment on the angle and polarization dependence of absorption; (2) theory of density profile steepening, compared with holographic interferometry measurements; and (3) theory of stimulated Brillouin scattering in long density gradients, compared with reflectivity measurements for long pulse, large focal spot experiments.
Date: October 17, 1977
Creator: Max, C.E.
System: The UNT Digital Library
ICF diagnostics. Revision 1 (open access)

ICF diagnostics. Revision 1

In the past several years there have been significant advances and accomplishments in the field of Inertial Confinement Fusion (ICF) research which are directly attributable to an active experimental program supported by the development and applications of sophisticated and specialized diagnostics instruments and techniques. The continued development of high temporal-and spatial-resolution diagnostics, although with a somewhat different technical emphasis than previously, is essential for maintaining progress in ICF. With the generation of inertial fusion drivers now becoming available progress toward higher density compression of fusion fuel will be attained at the expense of temperature, and consequently emissions from the targets will be limited. At the same time since the targets are being driven to higher density they are more opaque to the low-to-moderate energy x-rays (up to a few keV) and particles (alpha particles, protons, and knock-on charged particles) that have been utilized for diagnosing target performance.
Date: December 17, 1982
Creator: Coleman, L.W.
System: The UNT Digital Library
Quantum measurement and the mind-brain connection (open access)

Quantum measurement and the mind-brain connection

It is argued that quantum measurements do pose a problem, within the context created by the fundamental aim of science, which is identified as the construction of a cohesive, comprehensive, and rationally coherent idea of the nature of the world in which we live. Models of nature are divided into two classes: (1), those in which there is a selection process that, for any possible measurement, would, if that measurement were to be performed, pick out one single outcome, and, (2), all others. It is proved that any model of class that reproduces the predictions of quantum theory must violate the condition that there be no faster-than-light influences of any kind. This result is used to motivate the study of models in which unitary evolution is maintained and there is no selection of unique outcomes. A consideration of ontic probabilities, historical records, and the form of the mind-brain connection leads to an elaboration of the Everett many-worlds interpretation that appears to provide the basis of satisfactory solution of the measurement problem. 18 refs.
Date: October 17, 1990
Creator: Stapp, Henry P.
System: The UNT Digital Library
Status of the Lawrence Berkeley Laboratory and the Lawrence Livermore National Laboratory (LLNL) free electron laser (FEL). Revision 1 (open access)

Status of the Lawrence Berkeley Laboratory and the Lawrence Livermore National Laboratory (LLNL) free electron laser (FEL). Revision 1

A high-gain FEL experiment using the 10 kA, 4.5 MeV Experimental Test Accelerator (ETA) is described.
Date: November 17, 1983
Creator: Orzechowski, T. J.; Moebus, M. C.; Penko, F. A.; Prosnitz, D.; Rogers, D.; Chavis, C. S. et al.
System: The UNT Digital Library
Mixed waste treatment with a mediated electrochemical process (open access)

Mixed waste treatment with a mediated electrochemical process

The process described in this paper is intended to convert mixed waste containing toxic organic compounds (not heavy metals) to ordinary radioactive waste, which is treatable. The process achieves its goal by oxidizing hydrocarbons to CO{sub 2} and H{sub 2}O. Other atoms that may be present in the toxic organic generally are converted to nonhazardous anions such as sulfate and phosphate. This electro chemical conversion is performed at conditions of temperature and pressure that are just moderately above ambient conditions. Gaseous hydroxides and oxyhydroxides that are formed by many radionuclides during incineration cannot form in this process. 1 ref., 3 figs.
Date: May 17, 1991
Creator: Hickman, R. G.; Gray, L. W. & Chiba, Z.
System: The UNT Digital Library
Operation of a Free-Electron Laser from the Extreme Ultraviolet to the Water Window (open access)

Operation of a Free-Electron Laser from the Extreme Ultraviolet to the Water Window

We report results on the performance of a free-electron laser operating at a wavelength of 13.7 nm where unprecedented peak and average powers for a coherent extreme-ultraviolet radiation source have been measured. In the saturation regime, the peak energy approached 170 {micro}J for individual pulses, and the average energy per pulse reached 70 {micro}J. The pulse duration was in the region of 10 fs, and peak powers of 10 GW were achieved. At a pulse repetition frequency of 700 pulses per second, the average extreme-ultraviolet power reached 20mW. The output beam also contained a significant contribution from odd harmonics of approximately 0.6% and 0.03% for the 3rd (4.6 nm) and the 5th (2.75 nm) harmonics, respectively. At 2.75 nm the 5th harmonic of the radiation reaches deep into the water window, a wavelength range that is crucially important for the investigation of biological samples.
Date: December 17, 2007
Creator: Ackermann, W.; Asova, G.; Ayvazyan, V.; Azima, A.; Baboi, N.; Bahr, J. et al.
System: The UNT Digital Library
Statistical characterization of dislocation ensembles (open access)

Statistical characterization of dislocation ensembles

We outline a method to study the spatial and orientation statistics of dynamical dislocation systems by modeling the dislocations as a stochastic fiber process. Statistical measures have been introduced for the density, velocity, and flux of dislocations, and the connection between these measures and the dislocation state and plastic distortion rate in the crystal is explained. A dislocation dynamics simulation model has been used to extract numerical data to study the evolution of these statistical measures numerically in a body-centered cubic crystal under deformation. The orientation distribution of the dislocation density, velocity and dislocation flux, as well as the dislocation correlations have been computed. The importance of the statistical measures introduced here in building continuum models of dislocation systems is highlighted.
Date: May 17, 2006
Creator: El-Azab, A.; Deng, J. & Tang, M.
System: The UNT Digital Library
PROPERTIES OP LIQUID HELIUM-THREE IN THE TWO-BODY CORRELATION APPROXIMATION. I (open access)

PROPERTIES OP LIQUID HELIUM-THREE IN THE TWO-BODY CORRELATION APPROXIMATION. I

This is the first of two papers in which the low-temperature properties of liquid He{sup 3} are to be calculated in the thermodynamically consistent 'T-matrix' approximation. The set of coupled integral equations which are to be solved is exhibited in Part A of this paper. Part B of this paper is devoted to a preliminary, zero-temperature calculation which employs the additional approximations of using separable potentials and a noninteracting spectral function to define the interaction of two particles in the medium: the <T>{sub 0} approximation. In this approximation they obtain a spectral function for the quasi particles which they expect to display general features in common with those of the actual spectral function. Using this spectral function, they calculate the thermodynamic properties of the system and find that they compare favorably to those obtained in other calculations.
Date: November 17, 1965
Creator: Beck, Donald E. & Sessler, Andrew M.
System: The UNT Digital Library