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Pion correlations as a function of atomic mass in heavy ion collisions
The method of two pion interferometry was used to obtain source-size and lifetime parameters for the pions produced in heavy ion collisions. The systems used were 1.70 {center dot} A GeV {sup 56}Fe + Fe, 1.82 {center dot} A GeV {sup 40}Ar + KCl and 1.54 {center dot} A GeV {sup 93}Nb + Nb, allowing for a search for dependences on the atomic number. Two acceptances (centered, in the lab., at {approximately} 0{degrees} and 45{degrees}) were used for each system, allowing a search for dependences on the viewing angle. The correlation functions were calculated by comparing the data samples to background (or reference) samples made using the method of event mixing, where pions from different events are combined to produce a data sample in which the Bose-Einstein correlation effect is absent. The effect of the correlation function on the background samples is calculated, and a method for weighting the events to remove the residual correlation effect is presented. The effect of the spectrometer design on the measured correlation functions is discussed, as are methods for correcting for these effects during the data analysis. 58 refs., 39 figs., 18 tabs.
Date:
November 26, 1989
Creator:
Chacon, A.D.
Object Type:
Report
System:
The UNT Digital Library
Magnetic field, closed orbit, and energy measurement in the Bevatron
This report provides the information necessary for a better evaluation of particle energy in the Bevatron. Previously, the nominal magnetic field value and radius were used to calculate the value for the kinetic energy of the particle. This value was good to a few percent. Today, more and more experimenters would like to know the energy to a more precise value. To this end, corrections to the measured magnetic field values and the radial closed orbit are provided.
Date:
November 1, 1981
Creator:
Crebbin, K. C.
Object Type:
Report
System:
The UNT Digital Library
Issues for trigger processing at high luminosity colliders
A number of issues for the design of trigger processors at future high-luminosity, high-energy colliders such as the Superconducting Super Collider and the Large Hadron Collider are discussed.
Date:
November 1, 1989
Creator:
Lankford, A.J.
Object Type:
Article
System:
The UNT Digital Library
Hanford Environmental Dose Reconstruction Project Monthly Report
This monthly report summarizes the technical progress and project status for the Hanford Environmental Dose Reconstruction Project being conducted at Pacific Northwest Laboratory under the direction of a Technical Steering Panel.
Date:
November 1, 1989
Creator:
Dennis, B.S. (comp.)
Object Type:
Report
System:
The UNT Digital Library
Proceedings of the flat-plate solar array project research forum on photovoltaic metallization systems
A Photovoltaic Metallization Research Forum, under the sponsorship of the Jet Propulsion Laboratory's Flat-Plate Solar Array Project and the US Department of Energy, was held March 16-18, 1983 at Pine Mountain, Georgia. The Forum consisted of five sessions, covering (1) the current status of metallization systems, (2) system design, (3) thick-film metallization, (4) advanced techniques and (5) future metallization challenges. Twenty-three papers were presented.
Date:
November 15, 1983
Creator:
unknown
Object Type:
Article
System:
The UNT Digital Library
Enhanced durability and reactivity for zinc ferrite desulfurization sorbent
AMAX Research Development Center (AMAX R D) has been investigating methods for enhancing the reactivity and durability of the zinc ferrite desulfurization sorbent. Zinc ferrite sorbents are intended for use in desulfurization of hot coal gas in integrated gasification combined cycle (IGCC) or molten carbonate fuel cell (MCFC) applications. For the present program, the reactivity of the sorbent may be defined as its sulfur sorption capacity at the breakthrough point and at saturation in a bench-scale, fixed-bed reactor. Durability may be defined as the ability of the sorbent to maintain important physical characteristics such As size, strength, and specific surface area during 10 cycles of sulfidation and oxidation.
Date:
November 14, 1988
Creator:
Jha, Mahesh C. & Berggren, Mark H.
Object Type:
Report
System:
The UNT Digital Library
Results of the radiological survey at 12 Long Valley Road, Lodi, New Jersey (LJ054)
Maywood Chemical Works (MCW) of Maywood, New Jersey, generated process wastes and residues associated with the production and refining of thorium and thorium compounds from monazite ores from 1916 to 1956. MCW supplied rare earth metals and thorium compounds to the Atomic Energy Commission and various other government agencies from the late 1940s to the mid-1950s. Area residents used the sandlike waste from this thorium extracting process mixed with tea and cocoa leaves as mulch in their yards. Some of these contaminated wastes were also eroded from the site into Lodi Brook. At the request of the US Department of Energy (DOE), a group from Oak Ridge National Laboratory conducts investigative radiological surveys of properties in the vicinity of MCW to determine whether a property is contaminated with radioactive residues, principally {sup 232}Th, derived from the MCW site. The survey typically includes direct measurement of gamma radiation levels and soil sampling for radionuclide analyses. The survey of this site, 12 Long Valley Road, Lodi, New Jersey (LJ054), was conducted during 1985 and 1986. Results of the survey demonstrated no radionuclide concentrations in excess of the DOE Formerly Utilized Sites Remedial Action Program criteria. The radionuclide distributions were not significantly different …
Date:
November 1, 1989
Creator:
Foley, R.D.; Floyd, L.M. & Carrier, R.F.
Object Type:
Report
System:
The UNT Digital Library
Bumps and poles in the S-matrix: A systematic study of 0 sup ++ and 2 sup ++ mesons plus a molecule approach to the E(1420) in the K K. pi. system
The goal of Hadron Spectroscopy is to find the spectrum of states formed by color singlet arrangements of quarks and gluons. Ideally these spectral states are associated with poles of the scattering matrix of hadrons which are the decay channels of the states. For example the {rho} meson is the lowest q{bar q} s-wave, spin one color singlet state and decays into {pi}{sup +}{pi}{sup -}. Since the {rho}decays in a relative p-wave, one finds the {rho} pole in the I = 1 p-wave {pi}{pi} phase shifts. There are forces between quarks and gluons which do not manifest themselves as true resonances and thus cannot be described by a Breit-Wigner pole. I will give some examples that are not Breit-Wigner poles of the scattering matrix but are important bumps in meson production. 22 refs., 10 figs.
Date:
November 16, 1989
Creator:
Longacre, R. S.
Object Type:
Article
System:
The UNT Digital Library
Efficiencies of gas neutralizers for multi-MeV beams of light negative ions
Measurements are reported of the neutral and charged particle fractions produced by running beams of Li/sup -/, C/sup -/, O/sup -/, and Si/sup -/ at energies up to 7 MeV through gas cells of N/sub 2/, Ar, or CO/sub 2/. We discuss the implications of these measurements for the design of neutralizers to produce high energy light atom beams for heating or current drive in tokamaks.
Date:
November 1, 1981
Creator:
Grisham, L. R.; Post, D. E.; Johnson, B. M.; Jones, K. W.; Barette, J.; Kruse, T. H. et al.
Object Type:
Report
System:
The UNT Digital Library
Studies on transition metals and alloy Fischer-Tropsch catalysts, their electronic and bulk properties. (I: Fe/MnO; II: Fe/TiO/sub 2/; III: Fe/Mord. ). Final report, July 1, 1982-September 30, 1983
The objectives were: (1) to characterize samples D1, 10% FeO/90% MnO, and D2, 48% FeO/52% MnO, under varying conditions of reduction (at 250/sup 0/C or 350/sup 0/C in H/sub 2/) and of syngas reaction 1:1 of CO:H/sub 2/ at 290/sup 0/C) and in some cases use CO only for reduction and to identify species by Moessbauer Spectroscopy and Magnetization (sigma/sub s) measurement; (2) similarly, to see if there is any metal (oxide)/support (Mordenite) interaction by the same techniques. The characterization was carried out with above techniques and the kinetic results for syngas were obtained on the above systems mostly at PETC. During reduction of Fe-oxide/Mn-oxide an intermediate Mn-ferrite phase was detected. After reduction, species such as Fe/sup 0/+Fe/sup 3 +/+Fe/sup 2 +/ in varying total proportions (45% at 290/sup 0/C and Fe/sup 0/+Fe/sup 2 +/ 75% were found at 350/sup 0/C). Syngas conversion showed Fe-carbides (Fe/sub 2/C/sub 2/+Fe/sub 3/C) depending on the reaction conditions, and the composition of D/sub 1/ and D/sub 2/. With the fresh ..gamma..-Fe/sub 2/O/sub 3/ (identified by Moessbauer) on Mordenites with varying ratios of SiO/sub 2//Al/sub 2/O/sub 3/, a decrease in (sigma/sub s/) was found with lowering of the ratios from 60 to 17. At 17% …
Date:
November 1, 1983
Creator:
Mulay, L.N.
Object Type:
Report
System:
The UNT Digital Library
Hot-gas cleanup system model development. Volume I. Final report
This two-volume report summarizes the state of the art in performance modeling of advanced high-temperature, high-pressure (HTHP) gas cleanup devices. Volume I contains the culmination of the research effort carried over the past 12 months and is a summary of research achievements. Volume II is the user's manual for the computer programs developed under the present research project. In this volume, Section 2 presents background information on pressurized, fluidized-bed combustion concepts, a description of the role of the advanced gas cleanup systems, and a list of advanced gas cleanup systems that are currently in development under DOE sponsorship. Section 3 describes the methodology for the software architecture that forms the basis of the well-disciplined and structured computer programs developed under the present project. Section 4 reviews the fundamental theories that are important in analyzing the cleanup performance of HTHP gas filters. Section 5 discusses the effect of alkali agents in HTHP gas cleanup. Section 6 evaluates the advanced HTHP gas cleanup models based on their mathematical integrity, availability of supporting data, and the likelihood of commercialization. As a result of the evaluation procedure detailed in Section 6, five performance models were chosen to be incorporated into the overall system simulation …
Date:
November 1, 1982
Creator:
Ushimaru, K.; Bennett, A. & Bekowies, P.J.
Object Type:
Report
System:
The UNT Digital Library
Hadron-hadron physics at high energy and luminosity
I review some recent theoretical issues relevant to the physics of hadron-hadron collisions. I discuss processes where either energy or luminosity is the most important feature and emphasize the need for experiments at luminosities of 10{sup 33}cm{sup -2}sec{sup 1} if the full range of physics options is to be thoroughly explored. 22 refs., 10 figs.
Date:
November 8, 1989
Creator:
Hinchliffe, I.
Object Type:
Article
System:
The UNT Digital Library
Development of mild gasification process
Under a previous contract with Morgantown Energy Technology Center (METC), Department of Energy (DOE) Contract No. AC21-84MC21108, UCC Research Corporation (UCCRC) built and tested a 1500 lb/day Mild Gasification Process Development Unit (MGU). The MGU, as tested under the previous contract, is shown in Figure 1. Testing completed under the previous contract showed that good quality hydrocarbon liquids and good quality char can be produced in the MGU. However, the MGU is not optimized. The primary objectives of the current project are to optimize the MGU and determine the suitability of char for several commercial applications. The program consists of four tasks; Task 1 -- Test Plan; Task 2 -- Optimization of Mild Gasification Process; Task 3 -- Evaluation of Char and Char/Coal Blends as a Boiler/Blast Furnace Fuel; and Task 4 -- Analysis of Data and Preparation of Final Report. Task 1 has been completed while work continued on Task 2.
Date:
November 1, 1987
Creator:
Chu, C.I.C. & Gillespie, B.L.
Object Type:
Report
System:
The UNT Digital Library
Islets of stability beyond period doubling
Period doubling of a periodic orbit of an area preserving map appears to lead to the elimination of all closed invariant curves in the vicinity. We show, however, that there are always islets of stabilhty again beyond the accumulation point of the period doubling sequence.
Date:
November 1, 1981
Creator:
Mackay, R.S.
Object Type:
Report
System:
The UNT Digital Library
Phase-change thermal energy storage: Final subcontract report
The research and development described in this document was conducted within the US Department of Energy's Solar Thermal Technology Program. The goal of this program is to advance the engineering and scientific understanding of solar thermal technology and to establish the technology base from which private industry can develop solar thermal power production options for introduction into the competitive energy market. Solar thermal technology concentrates the solar flux using tracking mirrors or lenses onto a receiver where the solar energy is absorbed as heat and converted into electricity or incorporated into products as process heat. The two primary solar thermal technologies, central receivers and distributed receivers, employ various point and line-focus optics to concentrate sunlight. Current central receiver systems use fields of heliostats (two-axes tracking mirrors) to focus the sun's radiant energy onto a single, tower-mounted receiver. Point focus concentrators up to 17 meters in diameter track the sun in two axes and use parabolic dish mirrors or Fresnel lenses to focus radiant energy onto a receiver. Troughs and bowls are line-focus tracking reflectors that concentrate sunlight onto receiver tubes along their focal lines. Concentrating collector modules can be used alone or in a multimodule system. The concentrated radiant energy …
Date:
November 1, 1989
Creator:
unknown
Object Type:
Report
System:
The UNT Digital Library
Sodium compatibility of HT-9 and Fe-9Cr-1Mo steels
Ferritic steels have been receiving significant attention for possible use as steam generator tubing, and as alternate structural materials for liquid-metal heat-transport systems in commercial fast reactors, fusion reactors, etc. The materials are chosen on the basis of their high thermal conductivity, resistance to stress-corrosion-cracking in aqueous and steam environments, favorable fabricability and fairly low cost. These steels are available in several classes based on the microstructure and alloy content, viz., martensitics, bainitics, delta ferritics, and duplex steels. The low alloy bainitic steels (Fe-2-1/4Cr-1Mo) undergo extensive decarburization when exposed to high temperature flowing sodium. It is for this reason that ferritic steels with higher chromium (9 to 12% Cr) content have been proposed to minimize the carbon transfer and eventual degradation of mechanical properties. The martensitic steels, HT-9 and improved Fe9Cr1Mo are being considered as cladding/duct materials for liquid metal reactors (LMR). The alloy HT-9 is based on 12Cr1Mo composition. The improved Fe9Cr1Mo alloy is based on 9Cr1Mo composition as its name implies. The objective of the work reported here is to evaluate the sodium compatibility of the alloys at temperatures and flow rates typical of LMR cores. Testing was done for 8104 hours at 60/sup 0/C and 3992 hours …
Date:
November 1, 1985
Creator:
Anantatmula, R. P. & Brehm, W. F.
Object Type:
Article
System:
The UNT Digital Library
VUV (vacuum ultraviolet) laser diagnostics of H sup - ion sources
Vacuum ultraviolet laser absorption spectroscopy has been employed to measure the populations and temperatures of ground electronic state H-atoms and vibrationally-excited H{sub 2} molecules in a volume H{sup -} ion source. Measurements of both species have been made under a variety of discharge conditions. Vibrational levels to v{double prime}=8 have been measured, with the vibrational population distribution well described by a temperature of 4150K. 10 refs., 9 figs.
Date:
November 1, 1989
Creator:
Young, A. T.; Stutzin, G. C.; Leung, K. N. & Kunkel, W. B.
Object Type:
Article
System:
The UNT Digital Library
Time-Dependent Two-Dimensional Radiation Hydrodynamics of Accreting Matter Onto Highly Magnetized Neutron Stars
We present for the first time, the self-consistent solution of the two-dimensional, time-dependent equations of radiation-hydrodynamics governing the accretion of matter onto the highly magnetized polar caps of luminous x-ray pulsars. The calculations show a structure in the accretion column very different from previous one-zone uniform models. We have included all the relevant magnetic field corrections to both the hydrodynamics and the radiative transport. We include a new theory for the diffusion and advection of both radiation energy density and photon number density. For initially uniformly accreting models with super-Eddington flows, we have uncovered evidence of strong radiation-driven outflowing optically thin radiation filled regions of the accretion column embedded in optically-thick inflowing plasma. The development of these photon bubbles'' have growth times on the order of a millisecond and show fluctuations on sub-millisecond timescales. The photon bubbles are likely to be a consequence of convective over-stability and may result in observable fluctuations in the emitted luminosity leading to luminosity dependent changes in the pulse profile. This may provide important new diagnostics for conditions in accreting x-ray pulsars. 13 refs., 18 figs.
Date:
November 24, 1989
Creator:
Klein, R.I. (California Univ., Los Angeles, CA (USA). Dept. of Astronomy Lawrence Livermore National Lab., CA (USA) California Univ., Los Angeles, CA (USA). Inst. of Geophysics and Planetary Physics) & Arons, J. (California Univ., Berkeley, CA (USA). Dept. of Astronomy California Univ., Los Angeles, CA (USA). Inst. of Geophysics and Planetary Physics CEA Centre d'Etudes Nucleaires de Saclay, 91 -
Object Type:
Article
System:
The UNT Digital Library
Eastern Gas Shales Program. Completion and stimulation of five New York State Energy Research and Development Authority Wells Allegany and Cattaraugus Counties, New York
In order to evaluate the potential of the Devonian Shales as a source of natural gas, DOE/METC in Morgantown, West Virginia, has undertaken the Eastern Gas Shale Program (EGSP); not only to characterize and identify the resource, but also to enhance and improve the productivity of wells completed in the shale. One of the methods used to achieve improved productivity is hydraulic fracturing and, more specifically, foam fracturing. The efforts by DOE/METC included completion and stimulation of five New York State Energy Research and Development Authority (NYSERDA) wells; located in western Allegany County and southwestern Cattaraugus County, New York. The five wells were drilled on high shcool and college properties during the months of June and July 1981. DOE/METC's contribution to the program funded the stimulation and completion of the wells. This work was done under the engineering and field supervision of Gruy Federal, Inc. as contractor to DOE. The completion work took place in the months of July and August 1981. This consisted of running a cement bond log in each well. All logs showed good bonding. This was followed by perforating the Marcellus Shale through the 4-1/2-inch casing. During the next phase, the formation was broken down with …
Date:
November 1, 1981
Creator:
Rdissi, A.
Object Type:
Report
System:
The UNT Digital Library
Physical-Chemical Treatment of Tar Sand Processing Wastewater: [Final Report, Tasks 3-5]
The dewatering properties of residuals generated by flotation/foam fractionation treatment of TS-1S wastewater were evaluated. The leachate potential was studied for both chemical coagulation and flotation/foam fractionation sludges. A preliminary economic analysis was made comparing selected sludge disposal options and summarizing previously reported economic analysis of the chemical treatment alternatives.
Date:
November 1983
Creator:
King, Paul H.
Object Type:
Report
System:
The UNT Digital Library
Arsenic Removal From Gaseous Streams
Uranium feed materials, depending on the production process, have been found to contain arsenic (As) as a contaminant. Analyses show the As to be present as As pentafluoride (AsF{sub 5}) and/or hexafluoroarsenic acid (HAsF{sub 6}) and enter the enrichment cycle through contaminated hydrogen fluoride (HF). Problems related to corrosion of cylinder valves and plugging of feed lines and valves have been attributed to the As. Techniques to separate AsF{sub 5} from uranium hexafluoride (UF{sub 6}) using sodium fluoride (NaF) as a trapping media were successful and will be discussed. Procedures to significantly reduce (up to 97%) the level of As in HF will also be reported. 5 figs., 9 tabs.
Date:
November 22, 1989
Creator:
Russell, R. G. & Otey, M. G.
Object Type:
Report
System:
The UNT Digital Library
The geometry of the Virasoro group for physicists
Diff(S/sup 1/), the group of reparametrizations of the circle, is known as the Virasoro group in string theory. Reparametrizations keeping fixed a point of the circle form the quotient space Diff(S/sup 1/)S/sup 1/. The geometry of this space is relevant for string theory and string field theory. We describe this space as an infinite dimensional complex manifold with a Kaehler metric and compute ist Riemann tensor and its Ricci tensor. 7 refs
Date:
November 1, 1987
Creator:
Zumino, B.
Object Type:
Article
System:
The UNT Digital Library
Strange-quark-matter stars
We investigate the implications of rapid rotation corresponding to the frequency of the new pulsar reported in the supernovae remnant SN1987A. It places very stringent conditions on the equation of state if the star is assumed to be bound by gravity alone. We find that the central energy density of the star must be greater than 13 times that of nuclear density to be stable against the most optimistic estimate of general relativistic instabilities. This is too high for the matter to consist of individual hadrons. We conclude that it is implausible that the newly discovered pulsar, if its half-millisecond signals are attributable to rotation, is a neutron star. We show that it can be a strange quark star, and that the entire family of strange stars can sustain high rotation if strange matter is stable at an energy density exceeding about 5.4 times that of nuclear matter. We discuss the conversion of a neutron star to strange star, the possible existence of a crust of heavy ions held in suspension by centrifugal and electric forces, the cooling and other features. 34 refs., 10 figs., 1 tab.
Date:
November 1, 1989
Creator:
Glendenning, N. K.
Object Type:
Article
System:
The UNT Digital Library
Two-stage process for conversion of synthesis gas to high quality transportation fuels. Quarterly report, 8 June-30 September 1983
The design of two large hot-flow models, to be used for slurry bubble-column hydrodynamic studies, is described. Scoping experiments were performed in smaller models to study the effects of feed-gas distributor type, column diameter, and liquid medium on gas holdup and bubble sizes. In addition, a literature review of bubble-column hydrodynamics is presented. Modifications to improve the operation and flexibility of the existing two stage pilot plant have been designed and construction initiated. Also, a sample of reactor-wax was fractionated under vacuum in a laboratory still. 8 figures, 4 tables.
Date:
November 1, 1983
Creator:
Kuo, J.C.W.
Object Type:
Report
System:
The UNT Digital Library