Probing electroweak symmetry breaking at multi-TeV colliders (open access)

Probing electroweak symmetry breaking at multi-TeV colliders

Low energy theorems are derived for scattering of longitudinally polarized W and Z's, providing the basis for an estimate of the observable signal if electroweak symmetry breaking is due to new physics at the TeV scale. A pp collider with L, {radical}s {equals} 40 TeV, 10{sup 33}cm. {sup {minus}2}s{sup {minus}1} is just sufficient to observe the signal while pp colliders with 40, 10{sup 32} or 20, 10{sup 33} are not. A collider that is sensitive to the TeV-scale signal provides valuable information about symmetry breaking whether the masses of the associated new particles are below, within, or above the 1-2 TeV region. 6 refs., 6 figs., 2 tabs.
Date: March 26, 1987
Creator: Chanowitz, Michael S.
Object Type: Article
System: The UNT Digital Library
Present and future nuclear power generation as a reflection of individual countries' resources and objectives (open access)

Present and future nuclear power generation as a reflection of individual countries' resources and objectives

The nuclear reactor industry has been in a state of decline for more than a decade in most of the world. The reasons are numerous and often unique to the energy situation of individual countries. Two commonly cited issues influence decisions relating to construction of reactors: costs and the need, or lack thereof, for additional generating capacity. Public concern has ''politicized'' the nuclear industry in many non-communist countries, causing a profound effect on the economics of the option. The nuclear installations and future plans are reviewed on a country-by-country basis for 36 countries in the light of the resources and objectives of each. Because oil and gas for power production throughout the world are being phased out as much as possible, coal-fired generation currently tends to be the chosen alternative to nuclear power production. Exceptions occur in many of the less developed countries that collectively have a very limited operating experience with nuclear reactors. The Chernobyl accident in the USSR alarmed the public; however, national strategies and plans to build reactors have not changed markedly in the interim. Assuming that the next decade of nuclear power generation is uneventful, additional electrical demand would cause the nuclear power industry to experience …
Date: June 26, 1987
Creator: Borg, I.Y.
Object Type: Report
System: The UNT Digital Library
Transport vehicle for manned Mars missions powered by inertial confinement fusion (open access)

Transport vehicle for manned Mars missions powered by inertial confinement fusion

Inertial confinement fusion (ICF) is an ideal engine power source for manned spacecraft to Mars because of its inherently high power-to-mass ratios and high specific impulses. We have produced a concept for a vehicle powered by ICF and utilizing a magnetic thrust chamber to avoid plasma thermalization with wall structures and the resultant degradation of specific impulse that are unavoidable with the use of mechanical thrust chambers. This vehicle is capable of 100-day manned Mars missions with a 100-metric-ton payload and a total vehicle launch mass near 6000 metric tons, based on advanced technology assumed to be available by A.D. 2020. Such short-duration missions minimize radiation exposures and physiological deterioration of astronauts.
Date: June 26, 1987
Creator: Orth, C.D.; Klein, G.; Sercel, J.; Hoffman, N.; Murray, K. & Chang-Diaz, F.
Object Type: Article
System: The UNT Digital Library
Summary of EC Superelement Results for OH Inter-Module Connecting Forces (open access)

Summary of EC Superelement Results for OH Inter-Module Connecting Forces

The purpose of this report is to summarize the OH module connecting forces found as a result of the super-element modeling of the EC internal module structure. Although not presented here, this approach can also provide MH connecting forces and assembly deflections. This report includes only information on the OH connecting forces for various assumed connector schemes. The super-element machinery is in place to model other connector ideas, and provide information on overall deflections, MH connecting forces, and primary module stresses.
Date: May 26, 1987
Creator: Wands, R.; Weber, K. & Zurawski, J.
Object Type: Report
System: The UNT Digital Library
Transverse energy distribution, charged particle multiplicities and spectra in /sup 16/O--nucleus collisions (open access)

Transverse energy distribution, charged particle multiplicities and spectra in /sup 16/O--nucleus collisions

The HELIOS (High Energy Lepton and Ion Spectrometer) experiment, installed at the CERN Super Proton Synchrotron, proposes to examine in detail the physical properties of a state of high energy created in nuclei by ultra-relativistic nucleus-nucleus collisions. It is generally believed that, at high densities or temperatures, a phase transition to a plasma of quark and gluons will occur. The dynamic of the expansion of such a plasma and its subsequent condensation into a hadron gas should markedly affect the composition and momentum distribution of the emerging particles and photons. The HELIOS experimental setup therefore combines 4..pi.. calorimetric coverage with measurements of inclusive particle spectra, two particle correlations, low and high mass lepton pairs and photons. The emphasis is placed on transverse energy flow (E/sub /tau//) measurements with good energy resolution, and the ability to trigger the acquisition of data in a variety of E/sub /tau// ranges, thereby selecting the impact parameter or the violence of the collisions. This short note presents HELIOS results, for the most part still preliminary, on /sup 16/O--nucleus collisions at the incident energies of 60 and 200 GeV per nucleon. The E /sub /tau// distributions from Al, Ag and W targets are discussed and compared …
Date: November 26, 1987
Creator: Sunier, J. W.
Object Type: Article
System: The UNT Digital Library
Characterization of optical surface degradation: Angular resolved scatterometer (open access)

Characterization of optical surface degradation: Angular resolved scatterometer

The Angular Resolved Scatterometer (ARS) is a sensitive diagnostic instrument for quantitatively specifying the degree of degradation for optical surfaces. ARS test results are reported for coatings undergoing aboveground (AGT) prompt x-ray irradiation. With the ARS, the light scattered from an optical surface is measured as a function of scattering angle, wavelength, and polarization. From these data the power spectral density (PSD) is calculated and contains the bandwidth-limited spatial information about the surface. Subtle changes in surface properties (e.g., radiation-induced absorption, polarization changes, or localized incipient melting) that would not be detected by surface roughness or reflectance measurements appear as a significant PSD change. The ARS data are an integration over all spatial frequencies and thus accurately and uniquely characterize each surface.
Date: February 26, 1987
Creator: Edwards, D.F.; Gillespie, C.H. & Wirtenson, G.R.
Object Type: Article
System: The UNT Digital Library
OCH Strap Model Test (open access)

OCH Strap Model Test

The OCH Model was stacked using the appropriate spacers between each absorber plate. Steel bars measuring 3-inch wide by 1/4-inch thick were welded, using 1/8-inch fillet weld, along all the corner edges, except the outer radius edges. On the outer radius, the straps were bolted to the end plates and to plates 9 and 17. The straps on the outer radius were also set in towards the center by approximately 3-inches. The spacers were then knocked out. Twelve strain gauges were mounted on the model. See figure 1 and the OCH strap Model log book for locations. Each rosette was centered in the gap between two absorber plates. The finite element plate model can predict the primary deformations of the OH module in both the cantilever and crushing modes to within 11% of the measured values. The primary stresses away from the support plate for the cantilever mode can be predicted to within 13% by this model. Near the support plate where large shear stresses exists, ANSYS will overpredict the measured stresses substantially. This is probably due to the models inherent inability to allow for shear stress concentrations at the welds. The same over-prediction was seen in the side straps …
Date: August 26, 1987
Creator: Weber, K.
Object Type: Report
System: The UNT Digital Library
A CHRONIC INHALATION STUDY OF METHYL BROMIDE TOXICITY IN B6C3F1 MICE. (FINAL REPORT TO THE NATIONAL TOXICOLOGY PROGRAM) (open access)

A CHRONIC INHALATION STUDY OF METHYL BROMIDE TOXICITY IN B6C3F1 MICE. (FINAL REPORT TO THE NATIONAL TOXICOLOGY PROGRAM)

This report provides a detailed account of a two year chronic inhalation study of methyl bromide toxicity in B6C3Fl mice conducted for the National Toxicology Program. Mice were randomized into three dose groups (10, 33 and 100 ppm methyl bromide) and one control group (0 ppm) per sex and exposed 5 days/week, 6 hours/day, for a total of 103 weeks. Endpoints included body weight; clinical signs and mortality, and at 6, 15 and 24 months of exposure, animals were sacrificed for organ weights, hematology and histopathology. In addition, a subgroup of animals in each dosage group was monitored for neurobehavioral and neuropathological changes. After only 20 weeks of exposure, 48% of the males and 12% of the females in the 100 ppm group had died. Exposures were terminated in that group and the surviving mice were observed for the duration of the study. Exposure of B6C3Fl mice to methyl bromide, even for only 20 weeks, produced significant changes in growth rate, mortality, organ weights and neurobehavioral functioning. These changes occurred in both males and females, but were more pronounced in males.
Date: June 26, 1987
Creator: HABER, S.B.
Object Type: Report
System: The UNT Digital Library
Thermal properties of Permian Basin evaporites to 493 K and 30 MPa confining pressure (open access)

Thermal properties of Permian Basin evaporites to 493 K and 30 MPa confining pressure

Laboratory measurements have been made of the thermal conductivity and diffusivity of four rock salts, two anhydrites, and two dolomites bordering the Cycle 4 and Cycle 5 bedded salt formations in the Permian Basin in Deaf Smith County, Texas. Measurement conditions ranged from 303 to 473 K in temperature, and 0.1 to 31.0 MPa in hydrostatic confining pressure. Within the +-5% measurement resolution neither conductivity nor diffusivity showed a dependence upon pressure in any of the rocks. Conductivity and diffusivity in all rocks had a negative temperature dependence. For the two Cycle 4 salt samples, conductivity over the temperature range explored fell from 5.5 to 3.75 W/m.K, and diffusivity fell from about 2.7 to 1.7 x 10/sup -6/ m/sup 2//s. One of the Cycle 5 salts was a single crystal which had anomalous results, but the other had a low conductivity, about 3.4 W/m.K, with very weak temperature dependence, and a high diffusivity, 3.8 to 2.5 x 10/sup -6/ m/sup 2//s over the temperature range. In the nonsalts, conductivity and diffusivity decreased 10 to 20% over the temperature range explored, which was 308 < T < 373 K. Typical values at 308 K for conductivity were 5.4 W/m.K for both …
Date: January 26, 1987
Creator: Durham, W. B.; Heard, H. C.; Boro, C. O.; Keller, K. T.; Ralph, W. E. & Trimmer, D. A.
Object Type: Report
System: The UNT Digital Library