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Some frontiers of accelerator physics

Description: This paper discusses some concepts of future accelerators such as free electron lasers, two beam accelerator; and plasma-based adiabatic compressor. 12 refs., 10 figs., 5 tabs. (LSP)
Date: October 13, 1989
Creator: Sessler, A. M.
Partner: UNT Libraries Government Documents Department
open access

A fast large-area position-sensitive time-of-flight neutron detection system

Description: A new position-sensitive time-of-flight neutron detection and histograming system has been developed for use at the Intense Pulsed Neutron Source. Spatial resolution of roughly 1 cm {times} 1 cm and time-of-flight resolution of {approximately}1 {mu}sec are combined in a detection system which can ultimately be expanded to cover several square meters of active detector area. This system is based on the use of arrays of cylindrical one-dimensional position-sensitive proportional counters, and is … more
Date: October 13, 1989
Creator: Crawford, R.K. & Haumann, J.R.
Partner: UNT Libraries Government Documents Department
open access

ITER disruption modeling using TSC (Tokamak Simulation Code)

Description: Design of the ITER vacuum vessel (VV) is driven strongly by disruption-induced forces. We use the Tokamak Simulation Code (TSC) to model disruptions for the ITER physics phase (I{sub p} = 22 MA) and predict the time evolution of currents and forces on the VV. For a plasma vertically displaced to Z{sub axis} = {minus}1.0m before disruption and decaying at a rate of < dI{sub p}/dt > {approx equal} {minus}1.0MA/ms, the induced VV current peaks at 18 MA. The maximum radial VV force F{sub R} is 56 M… more
Date: November 13, 1989
Creator: Sayer, R. O.; Peng, Y. K. M.; Wesley, J. C.; Jardin, S. C. (Oak Ridge National Lab., TN (USA); General Atomics, San Diego, CA (USA) & Princeton Univ., NJ (USA). Plasma Physics Lab.)
Partner: UNT Libraries Government Documents Department
open access

L-shell photoabsorption spectroscopy for solid metals: Ti, V, Cr, Fe, Ni, Cu

Description: Synchrotron radiation measurements of near-threshold and broad-range (400--1500 eV) absolute photoabsorption cross sections were made for five transition metals with {plus minus}10% overall uncertainties. Fine structure details of 2p-3d autoionizing resonances are shown with better than 1.0 eV resolution for solid metals: Ti, V, Cr, Fe, Ni, and Cu. Fine structure similar to what we measured can be produced using a multi-configuration Dirac Fock (MCDF) model if a statistical distribution is assu… more
Date: September 13, 1989
Creator: Del Grande, N.K. (Lawrence Livermore National Lab., CA (USA))
Partner: UNT Libraries Government Documents Department
open access

Microwave Tokamak Experiment (MTX) ohmic heating system

Description: The ohmic heating system for the Microwave Tokamak Experiment (MTX) at Lawrence Livermore National Laboratory (LLNL) provides both the voltage for the initial breakdown phase and the energy to drive the plasma current to a value of 400 kA or greater. Providing this voltage and flux swing requires a one-turn loop voltage of about 25 volts (11 kV across the coil) and a magnetic flux swing of 2 volt- seconds. This voltage and flux swing are accomplished by charging the ohmic heating coils to 20 kA… more
Date: September 13, 1989
Creator: Jackson, M.C. (Lawrence Livermore National Lab., CA (USA))
Partner: UNT Libraries Government Documents Department
open access

Floating data acquisition system for microwave calorimeter measurements on MTX

Description: A microwave calorimeter has been designed for making 140-GHz absorption measurements on the MTX. Measurement of the intensity and spatial distribution of the FEL-generated microwave beam on the inner wall will indicate the absorption characteristics of the plasma when heated with a 140 GHz FEL pulse. The calorimeter works by monitoring changes of temperature in silicon carbide tiles located on the inner wall of the tokamak. Thermistors are used to measure the temperature of each tile. The tiles… more
Date: September 13, 1989
Creator: Sewall, N.R. & Meassick, S. (Lawrence Livermore National Lab., CA (USA))
Partner: UNT Libraries Government Documents Department
open access

Floating data acquisition system for microwave calorimeter measurements on MTX

Description: A microwave calorimeter has been designed for making 140-GHz absorption measurements on the MTX. Measurement of the intensity and spatial distribution of the FEL-generated microwave beam on the inner wall will indicate the absorption characteristics of the plasma when heated with a 140 GHz FEL pulse. The calorimeter works by monitoring changes of temperature in silicon carbide tiles located on the inner wall of the tokamak. Thermistors are used to measure the temperature of each tile. The tiles… more
Date: September 13, 1989
Creator: Sewall, N.R.
Partner: UNT Libraries Government Documents Department
open access

Introduction to the physics of ICF capsules

Description: Inertial Confinement Fusion is an approach to fusion which relies on the inertia of the fuel mass to provide confinement. To achieve conditions under which this confinement is sufficient for efficient thermonuclear burn, high gain ICF targets designed to be imploded directly by laser light. These capsules are generally a spherical shell which is filled with low density DT gas. The shell is composed of an outer region which forms the ablator and an inner region of frozen or liquid DT which forms… more
Date: March 13, 1989
Creator: Lindl, J.D.
Partner: UNT Libraries Government Documents Department
open access

Report of the QCD Working Group

Description: We discuss some current problems associated with the applications of QCD to event rates in high energy collisions. Emphasis is given to the current ambiguities and uncertainties that exist in estimates of signals and backgrounds. The production of jets and isolated photons at hadron colliders is discussed in some detail. The problems of jet definition are addressed. Some features of the events underlying the hard scattering process are discussed. 72 refs., 32 figs., 3 tabs.
Date: January 13, 1989
Creator: Hinchliffe, I. & Shapiro, M. D.
Partner: UNT Libraries Government Documents Department
open access

Physics of ignition for ICF capsules

Description: The implosion of an ICF capsule must accomplish both compression of the main fuel to several hundred grams per cubic centimeter and heating and compression of the central region of the fuel to ignition. This report discusses the physics of these conditions.
Date: March 13, 1989
Creator: Lindl, J.D.
Partner: UNT Libraries Government Documents Department
open access

Performance of a lead radiator, gas tube calorimeter

Description: Design and performance of a 4.2 radiation length lead-sandwich, gas tube hodoscope are discussed. The device, measuring 1 /times/ 2 m/sup 2/ in area and 12 cm in depth, was employed in Fermi National Accelerator Laboratory experiment 705. Multiple samplings of anode wires situated within three-walled aluminum tubes were used to generate an X coordinate; similarly, capacitively coupled copper-clad strips were ganged together to yield a Y coordinate. The results reviewed are based on an analysis … more
Date: March 13, 1989
Creator: Spiegel, L.; Arenton, M.; Chen, T. Y.; Conetti, S.; Cox, B.; Delchamps, S. W. et al.
Partner: UNT Libraries Government Documents Department
open access

Instability of compensated beam-beam collisions

Description: The beam-beam disruption phenomena in linear colliders are increasingly seen as a source of serious problems for these machines. A plasma compensation scheme, in which the motion of the plasma electrons in the presence of the colliding beams provides neutralizing charge and current densities, has been proposed and studied. But natural alternative to this scheme is to consider the overlapping of nearly identical high energy e/sup +/ and e/sup /minus// bunches, and the collision of two such pairs… more
Date: February 13, 1989
Creator: Rosenzweig, J.B.; Autin, B. & Chen, Pisin
Partner: UNT Libraries Government Documents Department
open access

['At the head of its class' article]

Description: A clipping of an article written by Janet Tyson for the Fort Worth Star-Telegram about Fort Worth school's art programs. It discusses the concerns for a lack of art-related courses in schools and points to Fort Worth as a leader in the initiative to bring them back with the help of NTIEVA and the Getty Center for Education in the Arts.
Date: April 13, 1989
Creator: Tyson, Janet
Partner: UNT Libraries Special Collections
open access

Induction linear accelerators for commercial photon irradiation processing

Description: A number of proposed irradiation processes requires bulk rather than surface exposure with intense applications of ionizing radiation. Typical examples are irradiation of food packaged into pallet size containers, processing of sewer sludge for recycling as landfill and fertilizer, sterilization of prepackaged medical disposals, treatment of municipal water supplies for pathogen reduction, etc. Volumetric processing of dense, bulky products with ionizing radiation requires high energy photon so… more
Date: January 13, 1989
Creator: Matthews, Stephen M.
Partner: UNT Libraries Government Documents Department
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