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Prospects for physics at e/sup +/e/sup -/ linear colliders (open access)

Prospects for physics at e/sup +/e/sup -/ linear colliders

The present thinking on high-energy e/sup /plus//e/sup /minus// linear colliders is reviewed, stressing those points that have consequences for detector design and physics analyses. Detector requirements are discussed. Experimental aspects of the physics that can be done at these colliders are discussed: first the general physics environment, then a standard process, W/sup /plus// W/sup /minus// detection, and finally four examples of the discovery potential of these colliders /emdash/ heavy quarks, heavy leptons, standard Higgs bosons, and charged Higgs bosons. The conclusions of this study will be stated. 23 refs., 40 figs.
Date: March 1, 1988
Creator: Feldman, G. J.
System: The UNT Digital Library
Severe accident core heatup transients in modular high temperature gas-cooled reactors without operating Reactor Cavity Cooling Systems (open access)

Severe accident core heatup transients in modular high temperature gas-cooled reactors without operating Reactor Cavity Cooling Systems

The ultimate decay heat removal system for the current Modular High Temperature Gas-Cooled reactors is a completely passive natural convection air cooling loop. This paper considers an extremely remote accident scenario, where even this passive system fails, and heat rejection is only via a layer of thermal insulation to the reactor silo structure and the surrounding soil. The results show that even in this case the peak fuel temperatures remain well within safe limits. However, vessel and concrete temperatures can - under extreme circumstances and after several weeks - reach temperature levels at which structural failure becomes possible.
Date: January 1, 1988
Creator: Kroeger, P. G.
System: The UNT Digital Library
First wall/blanket/shield design and optimization system (open access)

First wall/blanket/shield design and optimization system

First wall/blanket/shield design and optimization system (BSDOS) has been developed to provide a state-of-the-art design tool for fast accurate analysis. In addition, it has been designed to perform several other functions: (1) allowing comparison and evaluation studies for different concepts using the same data bases and ground rules, (2) permitting the use of any figure of merit in the evaluation studies, (3) optimizing the first wall/blanket/shield design parameters for any figure of merit under several design constraints, (4) permitting the use of different reactor parameters in the evaluation and optimization analyses, (5) allowing the use of improved eingineering data bases to study the impact on the design performance for planning future research and development, and (6) evaluating the effect of the data base uncertainties on the design performance. BSDOS is the first design and optimization system to couple the highly interacting neutronics, heat transfer, thermal hydraulics, stress analysis, radioactivity and decay-heat analyses, tritium balance, and capital cost. A brief description of the main features of BSDOS is given in this paper. Also, results from using BSDOS to perform design analysis for several reactor components are presented. 17 refs., 1 fig., 2 tabs.
Date: February 1, 1988
Creator: Gohar, Y.; Baker, C.; Attaya, H.; Cha, Y.; Majumdar, S. & Scandora, T.
System: The UNT Digital Library
Creating a word list for technical and clerical personnel (open access)

Creating a word list for technical and clerical personnel

The Savannah River Plant and Laboratory employ more than 16,000 people. When the separate Publications Divisions of the Plant and Laboratory were combined it was determined that a single source of information for using terms was needed, and that the source would take the form of a word list. The Word List was issued to more than 5000 employees onsite. In addition, the Word List is being added to the site computer network as a reference document and as an online spelling checker where more than 2000 employees will have access to it through their personal computers.
Date: May 1, 1988
Creator: Hammond, J S
System: The UNT Digital Library
Di-leptons at the Bevalac (open access)

Di-leptons at the Bevalac

Recent results on the production of di-leptons measured by the Di-Lepton-Spectrometer (DLS) collaboration are discussed. Results are reported from observations made on p /plus/ Be collisions with proton beams from 1.0 to 4.9 GeV and on Ca collisions with calcium beams of 1.0 to 2.0 GeV/A. The shape of the distributions are similar to that at higher energies. The low mass cross section appears to be explained by ..pi..-..pi.. annihilation, but detailed calculations are needed to substantiate that hypothesis. (LEN)
Date: March 1, 1988
Creator: Matis, H.S.
System: The UNT Digital Library
Structure functions: Their status and implications (open access)

Structure functions: Their status and implications

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.
System: The UNT Digital Library
Characterization of low-level waste from the industrial sector, and near-term projection of waste volumes and types (open access)

Characterization of low-level waste from the industrial sector, and near-term projection of waste volumes and types

A telephone survey of low-level waste generators has been carried out in order to make useful estimates of the volume and nature of the waste which the generators will be shipping for disposal when the compacts and states begin operating new disposal facilities. Emphasis of the survey was on the industrial sector, since there has been little information available on characteristics of industrial LLW. Ten large industrial generators shipping to Richland, ten shipping to Barnwell, and two whose wastes had previously been characterized by BNL were contacted. The waste volume shipped by these generators accounted for about two-thirds to three-quarters of the total industrial volume. Results are given in terms of the categories of LLW represented and of the chemical characteristics of the different wastes. Estimates by the respondents of their near-term waste volume projections are presented.
Date: January 1, 1988
Creator: MacKenzie, D.R.
System: The UNT Digital Library
A benchmark-problem specification and calculation using SENSIBL, a one- and two-dimensional sensitivity and uncertainty analysis code of the AARE system (open access)

A benchmark-problem specification and calculation using SENSIBL, a one- and two-dimensional sensitivity and uncertainty analysis code of the AARE system

The lack of suitable benchmark problems makes it difficult to test sensitivity codes with a covariance library. A benchmark problem has therefore been defined for one- and two-dimensional sensitivity and uncertainity analysis codes and code systems. The problem, representative of a fusion reactor blanket, has a simple, three-zone )tau)-z geometry containing a D-T fusion neutron source distributed in a central void region surrounded by a thick /sup 6/LiH annulus. The response of interest is the /sup 6/Li tritium production per source neutron, T/sub 6/. The calculation has been performed with SENSIBL using other codes from the AARE code system as a test of both SENSIBL and the linked, modular system. The caluclation was performed using the code system in the standard manner with a covariance data library in the COVFILS-2 format but modified to contain specifically tailored covariance data for H and /sup 6/Li (Path A). The calculation was also performed by a second method which uses specially perturbed H and Li cross sections (Path B). This method bypasses SENSIBL and allows a hand calculation of the benchmark T/sub 6/ uncertainties. The results of Path A and Path B were total uncertainties in T/sub 6/ of 0.21% and 0.19%, respectively. …
Date: January 1, 1988
Creator: Muir, D. W.; Davidson, J. W.; Dudziak, D. J.; Davierwalla, D. M.; Higgs, C. E. & Stepanek, J.
System: The UNT Digital Library
Operating experience and procedures at the tritium systems test assembly (open access)

Operating experience and procedures at the tritium systems test assembly

Operating procedures are important for the safe and efficient operation of the Tritium Systems Test Assembly (TSTA). TSTA has been operating for four years with tritium in a safe and efficient manner. The inventory of tritium in the process loop is 100 grams and several milestone runs have been completed. This paper describes the methods used to operate TSTA. 3 refs., 1 fig.
Date: January 1, 1988
Creator: Carlson, R.V.; Binning, K.E.; Cole, S. P.; Jenkins, E. M.; Wilhelm, R. C. & Cole, S. P.
System: The UNT Digital Library
Plutonium scrap recovery at Savannah River: Past, present, and vision of the future (open access)

Plutonium scrap recovery at Savannah River: Past, present, and vision of the future

As a result of the changing requirement, plus environmental and regulatory commitments, SRP now has essentially completed its paradigm shift. SRP has been transformed from primarily a reprocessor of irradiated uranium targets to primarily a reprocessor of non-specification plutonium. This is the mission which will carry SRP into the 21st Century. Accomplishment of the defined goals for the three-pronged RandD program will achieve several objectives: exploit new processes for recovering low-grade scraps; enhance SRP's position to incorporate pyrochemical processes where they are attractive or beneficial to plant scrap recovery; provide SRL/SRP with a capability to develop compatible aqueous pyrochemical processes; identify material compatibility requirements for the incorporation of pyrochemical processes at SRP; promote development and demonstration of improved NDA instrumentation to accurately measure plutonium holdups in solid residues; identify and implement the technology required for reagent preparation and atmospheric quality control; provide a means to compare economic options for emerging new processes; and as a result, identify process steps which will also put SRP in a position to readily adapt to changing plutonium missions.
Date: January 1, 1988
Creator: Gray, Leonard W.; Gray, John H.; Blancett, Allen L.; Lower, William M. & Rudisill, Tracy S.
System: The UNT Digital Library
Current drive and heating systems based on high-energy (1- to 3-MeV) negative ion beams (open access)

Current drive and heating systems based on high-energy (1- to 3-MeV) negative ion beams

This paper describes a concept for a current drive system based on negative ions with beam energy > 1 MeV. Preliminary physics calculations show that the core current necessary for stability enhancement can best be achieved by beams with energy ranging from 1 to 4 MeV. Further study and experiments will better define the optimum energy. Work under way at Oak Ridge National Laboratory (ORNL) and at collaborating institutes in Canada and the Federal Republic of Germany is defining a system, its elements, a configuration and operational scenarios deemed appropriate for such devices as ITER and other future steady-state tokamaks, and the requisite research and development to provide such a system. 7 refs., 2 figs.
Date: January 1, 1988
Creator: Becraft, W. R.; Akerman, M. A.; Haselton, H. H.; Murphy, B. D.; Lousteau, D. C.; Ryan, P. M. et al.
System: The UNT Digital Library
Pseudorapidity distributions and correlations in central sup 16 O interactions at 200 A GeV (open access)

Pseudorapidity distributions and correlations in central sup 16 O interactions at 200 A GeV

Whether or not adequate energy densities for a transition to the Quark-Gluon Plasma (QGP) phase are possible in {sup 16}O and {sup 32}S induced reactions is still an open question. Before unambiguous signals can be identified it is necessary to understand the background upon which the expected QGP signatures can be sought. An important aim of early experiments in this new energy density regime is thus to understand the process of hadronization in a nuclear environment. In any discussion of high energy nucleus-nucleus collisions formation time is an important feature. If, for example, the final state particles are produced instantaneously in a bound hadron-nucleon collision, all these particles will have a chance to reinteract inside the nuclear medium. If, on the other hand, the formation time is long, i.e., longer than the nuclear diameter, the energy flux will stay together as a unit throughout its passage through the target nucleus. While these extreme cases are clearly unrealistic, one expects interaction parameters such as the multiplicity and pseudorapidity distributions to be sensitive functions of the formation time. Here we present results on charged hadron production in an experiment using tracking detectors with the highest possible spatial resolution: emulsion chambers. A sample …
Date: January 1, 1988
Creator: Wilkes, R. J.
System: The UNT Digital Library
Modeling studies on the precipitation of Kr after implantation into metals (open access)

Modeling studies on the precipitation of Kr after implantation into metals

A rate-theory approach is applied to interpreting observations on the precipitation of Kr injected into Ni at temperatures between 25 and 560/degree/C. At temperatures of 400/degree/C or higher, the implanted Kr precipitates evolve into a bi-modal size distribution containing small solid precipitates and an additional population of larger, faceted bubbles. The calculations explore the dependence of the observed bi-modal distribution on the maximum size of the solid Kr precipitates and the effect of this dependence on bubble mobility. The analysis suggests that during the irradiation, whereas the large bubbles move by surface diffusion, the solid Kr precipitates are immobile. The relevance of the Kr-Ni interaction on the solid Kr precipitates size cutoff is discussed. 18 refs., 8 figs., 2 tabs.
Date: February 1, 1988
Creator: Rest, J.
System: The UNT Digital Library
A theoretical prediction of critical heat flux in subcooled pool boiling during power transients (open access)

A theoretical prediction of critical heat flux in subcooled pool boiling during power transients

Understanding and predicting critical heat flux (CHF) behavior during steady-state and transient conditions are of fundamenatal interest in the design, operation, safety of boiling and two-phase flow devices. This paper discusses the results of a comprehensive theoretical study made specifically to model transient CHF behavior in subcooled pool boiling. This study is based upon a simplified steady-state CHF model in terms of the vapor mass growth period. The results obtained from this theory indicate favorable agreement with the experimental data from cylindrical heaters with small radii. The statistical nature of the vapor mass behavior in transient boiling also is considered and upper and lower limits for the current theory are established. Various factors that affect the discrepancy between the data and the theory are discussed.
Date: January 1, 1988
Creator: Pasamehmetoglu, K. O.; Nelson, R. A. & Gunnerson, F. S.
System: The UNT Digital Library
A semi-analytical method for heat sweep calculations in fractured reservoirs (open access)

A semi-analytical method for heat sweep calculations in fractured reservoirs

An analytical approximation is developed for purely conductive heat transfer from impermeable blocks of rock to fluids sweeping past the rocks in fractures. The method was incorporated into a multi-phase fluid and heat flow simulator. Comparison with exact analytical solutions and with simulations using a multiple interacting continua approach shows very good accuracy, with no increase in computing time compared to porous medium simulations. 14 refs., 3 figs., 5 tabs.
Date: January 1, 1988
Creator: Pruess, K. & Wu, Y.S.
System: The UNT Digital Library
Detection of plasma equilibrium shifts with fiber optic sensing of image currents (open access)

Detection of plasma equilibrium shifts with fiber optic sensing of image currents

The radial equilibrium position of Reverse Field Pinch experiments is determined by the j x B force on the plasma. The current density is that of the toroidal plasma current and the B field is the vertical magnetic field which is present in the plasma. This magnetic field is the result of several components. The main field, generated by the toroidal current windings, is corrected by adjustable trim windings to achieve a desired equilibrium position. There is an additional component to the field due to induced image currents in the close fitting conducting shell which encircles the plasma. These currents vary in time due to the finite L/R time of the conducting shell. It is the object of this paper to investigate the possibility of measuring these shell currents accurately using fiber optics so as to provide an analog signal to the equilibrium feedback circuit. 7 refs., 7 figs.
Date: January 1, 1988
Creator: Forman, P.R.; Jahoda, F.C. & Miller, G.
System: The UNT Digital Library
Fusion energy development: Breakeven and beyond: Keynote address (open access)

Fusion energy development: Breakeven and beyond: Keynote address

The scientific feasibility, technological inevitability, and economic necessity of fusion as an energy source are discussed.
Date: February 1, 1988
Creator: Furth, H.P.
System: The UNT Digital Library
Sources of polarized ions and atoms (open access)

Sources of polarized ions and atoms

In this presentation we discuss methods of producing large quantities of polarized atoms and ions (Stern-Gerlach separation, optical pumping, and spin-exchange) as well as experimental methods of measuring the degree of polarization of atomic systems. The usefulness of polarized atoms in probing the microscopic magnetic surface properties of materials will also be discussed. 39 refs., 5 figs., 2 tabs.
Date: January 1, 1988
Creator: Cornelius, W.D.
System: The UNT Digital Library
Field characterization and personal dosimetry at a high energy ion accelerator (open access)

Field characterization and personal dosimetry at a high energy ion accelerator

The response of a variety of dosimeters was evaluated in the radiation field outside the shielding of the Lawrence Berkeley Laboratory Bevalac Biomedical Facility. The primary beam was 580 MeV/center dot/A neon ions, incident upon a 30.5-cm polyethylene cube. The field was characterized by a neutron spectrometer consisting of Bonner spheres and other detectors and by estimates of charged particle fluences in NTA film and in the Berklet spectrometer. The responses of American Acrylics CR-39 track-etch plastic detectors and AECL (Canada) type BD-100 Bubble Detectors were compared to those of NTA film, Andersson-Braun remmeter and recombination-chamber results as well as to reference dose equivalents based upon the unfolded neutron spectrum. Evaluations of these dosimeters are discussed. 7 refs., 4 figs.
Date: March 1, 1988
Creator: Greenhouse, N. A.; Busick, D. D.; de Castro, T. M.; Elwyn, A. J.; Hankins, D. E.; Ipe, N. E et al.
System: The UNT Digital Library
Permeability damage to natural fractures caused by fracturing fluid polymers (open access)

Permeability damage to natural fractures caused by fracturing fluid polymers

Formation damage studies using artificially fractured, low-permeability sandstone cores indicate that viscosified fracturing fluids can severely restrict gas flow through these types of narrow fractures. These studies were performed in support of the Department of Energy's Multiwell Experiment (MWX). Extensive geological and production evaluations at the MWX site indicate that the presence of a natural fracture system is largely responsible for unstimulated gas production. The laboratory formation damage studies were designed to examine changes in cracked core permeability to gas caused by fracturing fluid residues introduced into such narrow fractures during fluid leakoff. Polysaccharide polymers caused significant reduction (up to 95%) to gas flow through cracked cores. Polymer fracturing fluid gels used in this study included hydroxypropyl guar, hydroxyethyl cellulose, and xanthan gum. In contrast, polyacrylamide gels caused little or no reduction in gas flow through cracked cores after liquid cleanup. Other components of fracturing fluids (surfactants, breakers, etc.) caused less damage to gas flows. Other factors affecting gas flow through cracked cores were investigated, including the effects of net confining stress and non-Darcy flow parameters. Results are related to some of the problems observed during the stimulation program conducted for the MWX. 24 refs., 4 figs., 7 tabs.
Date: April 1, 1988
Creator: Gall, B. L.; Sattler, A. R.; Maloney, D. R. & Raible, C. J.
System: The UNT Digital Library
Coarse-node computations with an adaptive node structure (open access)

Coarse-node computations with an adaptive node structure

The analysis with COMMIX of liquid metal reactor (LMR) intermediate heat exchanger (IHX) transients that are characterized by low flows, and especially imbalanced low flows, shows that if a coarse-node structure is used the predicted temperatures are significantly different than those given by a fine-node structure. If a fine-node structure is used, for problems that involve a large part of the plant, the computation time becomes excessive. This paper presents an improved version of an adaptive node structure. At this stage this version has been applied only to one-dimensional problems.
Date: January 1, 1988
Creator: Tzanos, C.P.
System: The UNT Digital Library
Transient thermal analysis of three fast-charging latent heat storage configurations for a space-based power system (open access)

Transient thermal analysis of three fast-charging latent heat storage configurations for a space-based power system

A space-based thermal storage application must accept large quantities of heat in a short period of time at an elevated temperature. A model of a lithium hydride phase change energy storage system was used to estimate reasonable physical dimensions for this application which included the use of a liquid metal heat transfer fluid. A finite difference computer code was developed and used to evaluate three methods of enhancing heat transfer in the PCM energy storage system. None of these three methods, inserting thin fins, reticulated nickel, or liquid lithium, significantly improved the system performance. The use of a 95% void fraction reticulated nickel insert was found to increase the storage capacity (total energy stored) of the system slightly with only a small decrease in the system energy density (energy storage/system mass). The addition of 10% liquid lithium was found to cause minor increases in both storage density and storage capacity with the added benefit of reducing the hydrogen pressure of the lithium hydride. 9 refs., 7 figs., 2 tabs.
Date: January 1, 1988
Creator: Stovall, T. K. & Arimilli, R. V.
System: The UNT Digital Library
Full-wave calculations in flux coordinates for toroidal geometry (open access)

Full-wave calculations in flux coordinates for toroidal geometry

A new 2-D full-wave code, HYPERION, employing a poloidal and toroidal mode expansion and including the toroidal terms arising in the wave equation has been developed. It is based on the existing modules developed for the MHD stability codes and uses as input the tokamak equilibria calculated with the RSTEQ code. At present the plasma response is described by the collisionally broadened cold plasma conductivity. However, the code is written in straight field line coordinates, this permits the accurate representation of k /sub /parallel// and as a consequence allows the incorporation of the plasma Z functions. This code also retains the E/sub /parallel// component of the electric field which will allow the study of the low density region of the plasma. We have done detailed benchmarking of the HYPERION code in the cold plasma limit with the existing finite difference ORION full-wave code. The agreement is very good.
Date: January 1, 1988
Creator: Carreras, B. A.; Lynch, V. E.; Jaeger, E. F. & Batchelor, D. B.
System: The UNT Digital Library
Hyperdeformed nuclei and the residual pseudo-SU(3) symmetry (open access)

Hyperdeformed nuclei and the residual pseudo-SU(3) symmetry

The author discusses superdeformed and hypothetical hyperdeformed nuclei. Quadrupole deformations characteristic of these types of nuclei are defined. Symmetry features are also discussed. The characteristic cycle dependence of shell structures as functions of the deformation gives rise to chains of the deformed shell closures. Such a chain structure applies to moderately-, super- and hyper-deformed nuclei as well. The resulting total energy calculations give a systematic variation of super- and hyperdeformations with, e.g., increasing N at fixed Z, thus predicting the way nuclei deviate from the simple a:b = 2:1 and a:b = 3:1 symmetries.
Date: January 1, 1988
Creator: Dudek, J. & Werner, T.
System: The UNT Digital Library