An overview of spin physics (open access)

An overview of spin physics

Spin physics is playing an increasingly important role in high energy experiments and theory. This review looks at selected topics in high energy spin physics that were discussed at the 9th International Symposium on High Energy Spin Physics at Bonn in September 1990.
Date: July 1, 1991
Creator: Prescott, C. Y.
System: The UNT Digital Library
Low-frequency oscillations in radiative-convective models (open access)

Low-frequency oscillations in radiative-convective models

Although eastward propagation is usually regarded as an essential feature of the low-frequency Madden-Julian oscillation'' observed in the tropical atmosphere, many observations indicate that there is an important stationary or quasi-stationary component of the oscillation. Yasunari (1979), for example, investigated the stationary 30--60 day variation in upper tropospheric cloudiness in the Asian summer monsoon region. In a case study of the 30--60 day oscillation. Hsu et al. (1990) found a strong stationary oscillation of the divergence, outgoing longwave mdiadon and other fields. A recent observational study by Weickmann and Khalsa (1990) offers further evidence that the Madden-Julian oscillation has an important stationary component. In this paper, we present evidence that intraseasonal oscillations can be produced by local radiative and convective processes. This suggests that the observed propagating Madden-Julian wave is produced by interactions between these local processes and the large scale motion field, and is not essential for the existence of the observed oscillation.
Date: October 1991
Creator: Hu, Qi & Randall, David A.
System: The UNT Digital Library
A discrete ordinate response matrix method for massively parallel computers (open access)

A discrete ordinate response matrix method for massively parallel computers

A discrete ordinate response matrix method is formulated for the solution of neutron transport problems on massively parallel computers. The response matrix formulation eliminates iteration on the scattering source. The nodal matrices which result from the diamond-differenced equations are utilized in a factored form which minimizes memory requirements and significantly reduces the required number of algorithm utilizes massive parallelism by assigning each spatial node to a processor. The algorithm is accelerated effectively by a synthetic method in which the low-order diffusion equations are also solved by massively parallel red/black iterations. The method has been implemented on a 16k Connection Machine-2, and S[sub 8] and S[sub 16] solutions have been obtained for fixed-source benchmark problems in X--Y geometry.
Date: January 1, 1991
Creator: Hanebutte, U. R. & Lewis, E. E.
System: The UNT Digital Library
Intense beams at the micron level for the Next Linear Collider (open access)

Intense beams at the micron level for the Next Linear Collider

High brightness beams with sub-micron dimensions are needed to produce a high luminosity for electron-positron collisions in the Next Linear Collider (NLC). To generate these small beam sizes, a large number of issues dealing with intense beams have to be resolved. Over the past few years many have been successfully addressed but most need experimental verification. Some of these issues are beam dynamics, emittance control, instrumentation, collimation, and beam-beam interactions. Recently, the Stanford Linear Collider (SLC) has proven the viability of linear collider technology and is an excellent test facility for future linear collider studies.
Date: August 1, 1991
Creator: Seeman, J. T.
System: The UNT Digital Library
Development of a GPS-aided motion measurement, pointing, and stabilization system for a Synthetic Aperture Radar. [Global Positioning System (GPS)] (open access)

Development of a GPS-aided motion measurement, pointing, and stabilization system for a Synthetic Aperture Radar. [Global Positioning System (GPS)]

An advanced Synthetic Aperture Radar Motion Compensation System has been developed by Sandia National Laboratories (SNL). The system includes a miniaturized high accuracy ring laser gyro inertial measurement unit, a three axis gimbal pointing and stabilization assembly, a differential Global Positioning System (GPS) navigation aiding system, and a pilot guidance system. The system provides several improvements over previous SNL motion compensation systems and is capable of antenna stabilization to less than 0.01 degrees RMS and absolute position measurement to less than 5.0 meters RMS. These accuracies have been demonstrated in recent flight testing aboard a DHC-6-300 Twin Otter'' aircraft.
Date: January 1, 1991
Creator: Fellerhoff, J. R. & Kohler, S. M.
System: The UNT Digital Library
A probabilistic approach to information retrieval in heterogeneous databases (open access)

A probabilistic approach to information retrieval in heterogeneous databases

During the post decade, organizations have increased their scope and operations beyond their traditional geographic boundaries. At the same time, they have adopted heterogeneous and incompatible information systems independent of each other without a careful consideration that one day they may need to be integrated. As a result of this diversity, many important business applications today require access to data stored in multiple autonomous databases. This paper examines a problem of inter-database information retrieval in a heterogeneous environment, where conventional techniques are no longer efficient. To solve the problem, broader definitions for join, union, intersection and selection operators are proposed. Also, a probabilistic method to specify the selectivity of these operators is discussed. An algorithm to compute these probabilities is provided in pseudocode.
Date: August 1, 1991
Creator: Chatterjee, A. & Segev, A.
System: The UNT Digital Library
Addressing earthquake strong ground motion issues at the Idaho National Engineering Laboratory (open access)

Addressing earthquake strong ground motion issues at the Idaho National Engineering Laboratory

In the course of reassessing seismic hazards at the Idaho National Engineering Laboratory (INEL), several key issues have been raised concerning the effects of the earthquake source and site geology on potential strong ground motions that might be generated by a large earthquake. The design earthquake for the INEL is an approximate moment magnitude (M{sub w}) 7 event that may occur on the southern portion of the Lemhi fault, a Basin and Range normal fault that is located on the northwestern boundary of the eastern Snake River Plain and the INEL, within 10 to 27km of several major facilities. Because the locations of these facilities place them at close distances to a large earthquake and generally along strike of the causative fault, the effects of source rupture dynamics (e.g., directivity) could be critical in enhancing potential ground shaking at the INEL. An additional source issue that has been addressed is the value of stress drop to use in ground motions predictions. In terms of site geology, it has been questioned whether the interbedded volcanic stratigraphy beneath the ESRP and the INEL attenuates ground motions to a greater degree than a typical rock site in the western US. These three issues …
Date: January 1, 1991
Creator: Wong, Ivan G.; Silva, Walter J.; Stark, Cathy L.; Jackson, Suzette & Smith, Richard P.
System: The UNT Digital Library
Grouted support plates in reactor buildings at the Savannah River Site: Field investigation, tests, and seismic evaluation (open access)

Grouted support plates in reactor buildings at the Savannah River Site: Field investigation, tests, and seismic evaluation

The Westinghouse Savannah River Company (WSRC) conducted a seismic evaluation of the grouted support plates in the reactor buildings at the Savannah River Site (SRS) in response to issues raised from an earlier analysis. Researchers conducted the tests in a reactor building that was no longer in use and transferred the results to other reactor buildings. This paper discusses tests, results, analysis, and modifications made to achieve seismic qualification. 4 refs.
Date: January 1, 1991
Creator: Joshi, J. R. & Maryak, M. E.
System: The UNT Digital Library
Binghamton State Office Building: Decontamination of the basement mechanical room (open access)

Binghamton State Office Building: Decontamination of the basement mechanical room

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Date: October 1, 1991
Creator: Horn, E. G.; Aldous, K. M.; Eadon, G. A. (New York State Dept. of Health, Albany, NY (United States)); Dietz, R. N. (Brookhaven National Lab., Upton, NY (United States)); Honan, L. J. & Seiffert, K. K. (New York State Office of General Services, Albany, NY (United States))
System: The UNT Digital Library
The Brookhaven rare kaon decay program (open access)

The Brookhaven rare kaon decay program

The results of the current generation of rare kaon decay experiments at Brookhaven National Laboratory are reviewed. The present status of and future plans for such experiments are discussed.
Date: January 1, 1991
Creator: Littenberg, L. S.
System: The UNT Digital Library
Experiments on nucleon spin-dependent structure functions (open access)

Experiments on nucleon spin-dependent structure functions

In this presentation, the earlier measurements of the spin-dependent structure function of the proton in experiments at SLAC and at CERN are reviewed. In addition several new deep inelastic scattering experiments to measure the spin-dependent structure functions of the nucleon, both proton and neutron, will be discussed.
Date: January 1, 1991
Creator: Igo, G. (California Univ., Los Angeles, CA (United States). Dept. of Physics) & Hughes, V. W. (Yale Univ., New Haven, CT (United States). Dept. of Physics)
System: The UNT Digital Library
Development of the MIT tabletop soft x-ray laser (open access)

Development of the MIT tabletop soft x-ray laser

We have been developing a small-scale EUV laser facility at MIT with which we hope to observe gain in nickel-like molybdenum at 191 {angstrom}. The physics involved in the formation of laser gain is examined through the use of simple models, and optimum operating temperatures and electron densities are determined. The upper state population is determined primarily through a balance between direct collisional excitation to and from the upper laser state; the lower state population follows primarily from a balance between indirect excitation and radiative decay. Models describing these balances are used to estimate optimum conditions and the resulting population inversions.
Date: January 1, 1991
Creator: Hagelstein, P. L.
System: The UNT Digital Library
Over-the-road testing of radioactive materials packagings (open access)

Over-the-road testing of radioactive materials packagings

Sandia National Laboratories has an ongoing program to characterize the environments encountered during normal surface transport of radioactive materials. This effort consists of obtaining experimental data from both road simulator and over-the-road tests and of analyzing the dam to obtain numerical models to simulate those environments. These data and models have been used to define the design basis for resistance to shock and vibration and the requirements for tiedowns of truck-transported radioactive materials. This work is in conjunction with the American National Standards Institute (ANSI) standards development for radioactive materials transport. This paper summarizes the data from a series of over-the-road tests performed with Chem-Nuclear Systems, Inc. equipment near Barnwell, South Carolina. The data include packaging responses to driving over various road types as well as measurements of packaging and trailer responses to hard braking and turning events. The data also include the responses of both flexible and rigid tiedown systems. The results indicate that the tiedown forces for these tests were less than 0.06 g based on packaging weight.
Date: January 1, 1991
Creator: Glass, R. E. & Gwinn, K. W.
System: The UNT Digital Library
A Model for Calculation of RCS Pressure During Reflux Boiling Under Reduced Inventory Conditions and Its Assessment Against PKL Data. [Reactor Cooling Systems (Rcs)] (open access)

A Model for Calculation of RCS Pressure During Reflux Boiling Under Reduced Inventory Conditions and Its Assessment Against PKL Data. [Reactor Cooling Systems (Rcs)]

There has been recent interest in the United States concerning the loss of residual heat removal system (RHRS) under reduced coolant inventory conditions for pressurized water reactors. This issue is also of interest in the Federal Republic of Germany and an experiment was performed in the integral PKL-HI experimental facility at Siemens-KWU to supply applicable data. Recently, an NRC-sponsored effort has been undertaken at the Idaho-National Engineering Laboratory to identify and analyze the important thermal-hydraulic phenomena in pressurized water reactors following the long term loss-of-RHRS during reduced inventory operation. The thermal-hydraulic response of a closed reactor coolant system during such a transient is investigated in this report. Some of the specific processes investigated include: reflux condensation in the steam generators, the corresponding pressure increase in the reactor coolant system, and void fraction distributions on the primary side of the system. Mathematical models of these and other physical processes Experiment B4.5.
Date: January 1, 1991
Creator: Palmrose, D. E. (EG and G Idaho, Inc., Idaho Falls, ID (United States)) & Mandl, R. M. (Siemens AG, Berlin (Germany))
System: The UNT Digital Library
Application of the SQUG-GIP to the seismic upgrade program of the Savannah River reactors (open access)

Application of the SQUG-GIP to the seismic upgrade program of the Savannah River reactors

In August 1991, the Savannah River Site (SRS) seismic evaluation program using the Generic Implementation Procedure (GIP) celebrated its third anniversary -- a respectable age for such a new methodology. During these three years, the GIP, developed for the commercial nuclear industry's Seismic Qualification Utility Group (SQUG), had evolved through Revision 0, Revision 1, Revision 2 and a Revision 2 update'' which is currently in the works. This evolution is not surprising for such an important, and in many ways pioneering, document. The various revisions were anticipated at SRS, and the program adjusted accordingly. The verification of seismic adequacy of equipment at the SRS nuclear reactors has been outlined in previous publications. The purpose of this paper is to relate the more practical and managerial aspects of our relatively mature SQUG-GIP implementation program, which will hopefully prove useful to future users of the GIP. This report is divided into four sections, which follow the normal flow of work under GIP: (1) Program Prerequisites (2) Definition of Scope (3) Equipment Evaluations, and (4) Resolution of Outliers.
Date: January 1, 1991
Creator: Antaki, G. A.
System: The UNT Digital Library
Transient x-ray laser schemes at 1. mu. and at 2. mu (open access)

Transient x-ray laser schemes at 1. mu. and at 2. mu

The development of a pump laser for X-ray lasers which operates at wavelengths longer than 1 {mu} would permit the attainment of higher electron temperatures for a given pump intensity. Such a system would be of interest for electron collisional schemes at low Z, and would have the potential to improve the overall system efficiency. An initial design for an optical parametric oscillator which would down-convert 1 {mu} radiation to 2 {mu} is presented.
Date: January 1, 1991
Creator: Hagelstein, P.; Goodberlet, J. & Basu, S.
System: The UNT Digital Library
Investigations of hydrodenitrogenation of quinoline over molydenum nitride (open access)

Investigations of hydrodenitrogenation of quinoline over molydenum nitride

An investigation has been carried out of the reaction pathway for the hydrodenitrogenation of quinoline over Mo{sub 2}N. Quinoline is found to undergo a rapid hydrogenation to form 1,2,3,4,-tetrahydroquinoline. This product then reacts more slowly to form 2-propylanaline, which in turn undergoes hydrogenolysis of the C-N bond in the saturated ring to form propylbenzene. No evidence is found for propylcyclohexane.
Date: December 1, 1991
Creator: Lee, K. S.; Reimer, J. A. & Bell, A. T.
System: The UNT Digital Library
Polarizing optics for the soft x-ray regime: Whispering-gallery mirrors and multilayer beamsplitters (open access)

Polarizing optics for the soft x-ray regime: Whispering-gallery mirrors and multilayer beamsplitters

Two short-wavelength optical components are described. The first, the whispering-gallery mirror, uses many glancing-incidence reflections to deflect a beam through a large net angle. Because the Fresnel coefficient for each reflection depends upon the state of polarization, the whispering-gallery mirror can act both as a polarizer and as a birefringent element. The second, the multilayer polarizing beamsplitter, is a Brewster-angle reflector thin enough to allow partial partial transmission of the incident beam. Its behavior can be surprising; in some cases the same polarization mode is preferred on both reflection and transmission.
Date: January 1, 1991
Creator: Braud, J. P.
System: The UNT Digital Library
Grid orientation effects in the simulation of cold water injection into depleted vapor zones (open access)

Grid orientation effects in the simulation of cold water injection into depleted vapor zones

A considerable body of field experience with injection has been accumulated at Larderello, Italy and The Geysers, California; the results have been mixed. There are well documented cases where injection has increased flow rates of nearby wells. Return of injected fluid as steam from production wells has been observed directly through chemical and isotopic changes of produced fluids (Giovannoni et al., 1981; Nuti et al., 1981). In other cases injection has caused thermal interference and has degraded the temperature and pressure of production wells. Water injection into depleted vapor zones gives rise to complex two-phase fluid flow and heat transfer processes with phase change. These are further complicated by the fractured-porous nature of the reservoir rocks. An optimization of injection design and operating practice is desirable; this requires realistic and robust mathematical modeling capabilities.
Date: January 1, 1991
Creator: Pruess, K.
System: The UNT Digital Library
Novel characteristics of VUV insertion device beamlines at the Advanced Light Source (open access)

Novel characteristics of VUV insertion device beamlines at the Advanced Light Source

The design of VUV beamlines for the Advanced Light Source is discussed. Features of the design serve to illustrate the careful attention required in order to preserve the performance of the low emittance third generation'' storage ring, operating with insertion devices. 11 refs.
Date: October 1, 1991
Creator: Warwick, T. & Heimann, P.
System: The UNT Digital Library
Silicon on insulator structures in selective epitaxial growth (open access)

Silicon on insulator structures in selective epitaxial growth

Silicon-on-insulator structures were formed by the selective epitaxial growth (SEG) of silicon and the epitaxial lateral overgrowth (ELO) of oxide shapes using an LPCVD hot-walled reactor at 850{degrees}C. The homoepitaxial interface changed character with modifications of the gas composition during the in-situ pre-epitaxial bake at 900{degrees}C. HREM images show ellipsoid-shaped inclusions lying along the homoepitaxial interface for silicon growth conduced with no dichlorosilane (DCS) flow during the prebake in H{sub 2}. SIMS analysis indicates a large oxygen, fluorine, and carbon concentration at the interface. For structures grown with a small DCS flow in addition to H{sub 2} during the prebake, the homoepitaxial structural defects and the oxygen, fluorine, and carbon peaks are removed.
Date: November 1, 1991
Creator: Weng, Z.; Gronsky, R.; Lou, J. & Oldham, W.
System: The UNT Digital Library
Application of the Moyer method to transverse shielding of linear Bremsstrahlung sources (open access)

Application of the Moyer method to transverse shielding of linear Bremsstrahlung sources

The Moyer method is applied to the design of transverse shielding for an electron linear accelerator, assuming uniform beam power loss along the accelerator structure. Parameters for this application are given and sample calculations are shown. For a beam power loss uniformly distributed with distance along a straight line of 0.5W m{sup {minus}1}, it is predicted that 1.2 m of concrete are needed to reduce the dose equivalent rate to 1.39 {times} 10{sup {minus}8} Sv s{sup {minus}1}, (5 mrem hour{sup {minus}1}) at a transverse distance of 3.5 m from the source.
Date: December 1, 1991
Creator: Swanson, W. P.; Sun, R. K. & Thomas, R. H.
System: The UNT Digital Library
The diagnostics system for the multiple heavy ion beams induction linac experiment, MBE-4 (open access)

The diagnostics system for the multiple heavy ion beams induction linac experiment, MBE-4

MBE-4 is a four beam current amplifying induction linac experiment conducted at LBL as a part of the Heavy Ion Fusion Accelerator Research (HIFAR) program for studying accelerator physics issues of a heavy ion driver for inertial fusion. The four ion beams (Cs{sup +}, 10 mA) are focused by electrostatic quadrupoles and accelerated fro about 200 keV to 900 keV through 24 induction gaps. Current amplification of up to nine times is achieved while the beam pulse duration is compressed from about 3 {mu}s to 0.5 {mu}s. The diagnostic system enables the complete time-resolved 2-D transverse phase space distribution of the beam to be measured. Reduction of the raw data yields the beam current, current profile, emittance, centroid position and angle as well as the beam envelope parameters. In addition, the longitudinal energy distribution is obtained from measurements using a calibrated electrostatic spectrometer. The diagnostic system hardware, as well as the data acquisition and reduction routines, are controlled by an IBM pc-XT. We shall describe the diagnostic system and discuss its performance in view of the specific issues which result from the acceleration and amplification of multiple beams of heavy ions.
Date: September 1, 1991
Creator: Eylon, S.
System: The UNT Digital Library
Sulfur polymer cement, a new stabilization agent for mixed and low- level radioactive waste (open access)

Sulfur polymer cement, a new stabilization agent for mixed and low- level radioactive waste

Solidification and stabilization agents for radioactive, hazardous, and mixed wastes are failing to pass governmental tests at alarming rates. The Department of Energy's National Low-Level Waste Management Program funded testing of Sulfur Polymer Cement (SPC) by Brookhaven National Laboratory during the 1980s. Those tests and tests by the US Bureau of Mines (the original developer of SPC), universities, states, and the concrete industry have shown SPC to be superior to hydraulic cements in most cases. Superior in what wastes can be successfully combined and in the quantity of waste that can be combined and still pass the tests established by the US Environmental Protection Agency and the US Nuclear Regulatory Commission.
Date: January 1, 1991
Creator: Darnell, G. R.
System: The UNT Digital Library