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Design and operation of an inert gas facility for thermoelectric generator storage

Description: While the flight hardware is protected by design from the harsh environments of space, its in-air storage often requires special protection from contaminants such as dust, moisture and other gases. One of these components, the radioisotope thermoelectric generator (RTG) which powers the missions, was deemed particularly vulnerable to pre-launch aging because the generators remain operational at core temperatures in excess of 1000 degrees centigrade throughout the storage period. Any oxygen perm… more
Date: January 1, 1990
Creator: Goebel, C. J.
Partner: UNT Libraries Government Documents Department
open access

A study of tau decays of the W boson at CDF (Collider Detector at Fermilab)

Description: A report is given of a search for tau decays of the W boson in p{bar p} collisions at {radical}s = 1.8 TeV using the Collider Detector at Fermilab (CDF). A description of a hardware trigger specifically designed to enhance the number of events with tau decays is presented along with the results of a preliminary analysis of data taken during the 1988--89 run of CDF. 10 refs., 4 figs.
Date: January 3, 1990
Creator: Gladney, L. D.
Partner: UNT Libraries Government Documents Department
open access

The product consistency test for the DWPF wasteform

Description: The preliminary specifications on the glass wasteform to be produced by the Defense Waste Processing Facility (DWPF) require extensive characterization of the glass product both before actual production begins and then during production. To aid in this characterization, a leach test was needed that was easily reproducible, could be performed remotely on highly radioactive samples, and could yield results rapidly. Several standard leach tests were examined with a variety of test configurations. … more
Date: January 1, 1990
Creator: Jantzen, Carol M. & Bibler, N. E.
Partner: UNT Libraries Government Documents Department
open access

The electronics and data acquisition system for the Wire Imaging Synchrotron Radiation Detector at the SLC (Stanford Linear Collider)

Description: The Stanford Linear Collider (SLC) located at the Stanford Linear Accelerator Center collides electrons and positrons produced in the linear accelerator pulse by pulse. We determine the energy of each beam by measuring the angle of deflection of the beam in the SLC extraction lines. Each extraction line consists of two bending magnets that produce synchrotron radiation, and a spectrometer analyzing magnet that deflects the beam. We detect the synchrotron light by using the emission of electrons… more
Date: January 1, 1990
Creator: Rouse, F.; Briggs, D.D. (Stanford Linear Accelerator Center, Menlo Park, CA (USA)); Gomez, J.J.; Von Zanthier, C. & Kent, J. (California Univ., Santa Cruz, CA (USA))
Partner: UNT Libraries Government Documents Department
open access

An optimized algorithm for solving the nodal diffusion method on shared memory multiprocessors

Description: Nodal methods play a special role in reactor physics calculations. In recent papers the high computational efficiency of nodal methods has been established and the development of more efficient algorithms tailored to the advanced architectures of modern day computers proposed. The rapidly changing architectures of today's computer influence the way codes have to be programmed so that reasonable speed up and efficiency are attained. We have applied these concepts in solving the one-group neutron… more
Date: January 1, 1990
Creator: Kirk, B.L. & Azmy, Y.Y.
Partner: UNT Libraries Government Documents Department
open access

A many particle-tracking detector with drift planes and segmented cathode readout

Description: We describe the design and performance of a detector system for tracking charged particles in an environment of high track density and rates up to 1 MHz. The system operates in the forward spectrometer of the BNL Heavy Ion experiment E814 and uses principles of general interest in high rate, high multiplicity applications such as at RHIC or SSC. We require our system to perform over a large dynamic range, detecting singly charged particles as well as fully ionized relativistic {sup 28}Si. Resul… more
Date: January 1, 1990
Creator: Fischer, J.; Lissauer, D.; Ludlam, T.; Makowiecki, D.; O'Brien, E.; Radeka, V. et al.
Partner: UNT Libraries Government Documents Department
open access

Design of a full scale model fuel assembly for full power production reactor flow excursion experiments

Description: A novel full scale production reactor fuel assembly model was designed and built to study thermal-hydraulic effects of postulated Savannah River Site (SRS) nuclear reactor accidents. The electrically heated model was constructed to simulate the unique annular concentric tube geometry of fuel assemblies in SRS nuclear production reactors. Several major design challenges were overcome in order to produce the prototypic geometry and thermal-hydraulic conditions. The two concentric heater tubes (to… more
Date: January 1, 1990
Creator: Nash, C. A. (Westinghouse Savannah River Co., Aiken, SC (United States)); Blake, J. E. & Rush, G. C. (Babcock and Wilcox Co., Alliance, OH (United States))
Partner: UNT Libraries Government Documents Department
open access

Pseudorapidity densities and fluctuations in central sup 32 S interactions at 200A GeV

Description: Observations of heavy ion interactions at the highest available accelerator energies provide essential information for the analysis and interpretation of cosmic ray interactions. We report on an experiment in which emulsion chamber detectors were exposed to beams of 200A GeV {sup 32}S ions at the CERN SPS. We present statistical features of pseudorapidity distributions from central collisions in the experimental sample and compare them with the predictions from the Lund Model (FRITIOF) which co… more
Date: January 1, 1990
Partner: UNT Libraries Government Documents Department
open access

Considerations for high-brightness electron sources

Description: Particle accelerators are now used in many areas of physics research and in industrial and medical applications. New uses are being studied to address major societal needs in energy production, materials research, generation of intense beams of radiation at optical and suboptical wavelengths, treatment of various kinds of waste, and so on. Many of these modern applications require a high intensity beam at the desired energy, along with a very good beam quality in terms of the beam confinement, … more
Date: January 1, 1990
Creator: Jameson, Robert A.
Partner: UNT Libraries Government Documents Department
open access

A bulk niobium superconducting quarter wave resonator

Description: A bath-cooled all-niobium 160 MHz quarter wave resonator prototype was constructed and tested. The objective of this research has been the development of a high performance accelerating element with {beta}{sub opt} {approx equal} 0.11 for the ALPI linac at the Laboratori Nazionali di Legnaro. The design of this resonator was based upon a previous 150 MHz model, with minor changes due to the different frequency and to modified welding procedure. An accelerating field of 5 MV/m was achieved at a … more
Date: January 1, 1990
Creator: Ben-Zvi, Ilan; Chiaveri, E.; Elkonin, B. V.; Facco, A. & Sokolowski, J. S.
Partner: UNT Libraries Government Documents Department
open access

Negative ion-based neutral injection on DIII-D

Description: High energy negative ion-based neutral beam injection is a strong candidate for heating and non-inductive current drive in tokamaks. Many of the questions related to the physics and engineering of this technique remain unanswered. In this paper, we consider the possibility of negative ion-based neutral beam injection on DIII-D. We establish the desired parameter space by examining physics trades. This is combined with potential design constraints and a survey of component technology options to … more
Date: January 1, 1990
Creator: Stewart, L. D.; Bhadra, D. K.; Colleraine, A. P. & Kim, J.
Partner: UNT Libraries Government Documents Department
open access

Theoretical modeling and experimental characterization of planar defects in Y sub 2 Ba sub 4 Cu sub 6+x O sub 14+x

Description: Crystallographic defects and phase transformations in the system Y{sub 2}Ba{sub 4}Cu{sub 6 + x}O{sub 14 + x}(0{le}{times}{le}4) are investigated by high resolution transmission electron microscopy (TEM) and static lattice, three dimensional Monte Carlo computer simulations. High resolution images of partially transformed (x = 2 to x = 1) material reveal a prevalence of CuO planar defects (stacking faults) associated with the transformation and an absence of disturbance to the perovskite Ba-Y-Ba… more
Date: November 1, 1990
Creator: Burmester, C. P.; Fendorf, M.; Gronsky, R. & Wille, L. T.
Partner: UNT Libraries Government Documents Department
open access

Prototype photon position monitors for undulator beams at the Advanced Light Source

Description: Design criteria are described, and test results are presented, for prototype ALS undulator beam position monitors. The design is based on monitors presently in use at NSLS, with modifications to account for the widely varying and large K values of the undulators to be installed at the ALS. In particular, we have modified the design to simplify the thermal engineering and we have explored techniques to suppress the response of the monitors to soft photons, so that the beam position can be determ… more
Date: October 17, 1990
Creator: Warwick, T.; Shu, D. (Lawrence Berkeley Lab., CA (United States)); Rodricks, B. (Argonne National Lab., IL (United States)) & Johnson, E.D. (Brookhaven National Lab., Upton, NY (United States))
Partner: UNT Libraries Government Documents Department
open access

Vertical bridgman and gradient freeze growth of III-V compound semiconductors

Description: Major improvements in the structural and electrical perfection of single crystals of III-V compound semiconductors have been achieved by using new vertical Bridgman-type and vertical gradient freeze techniques. A general review of experimental set-ups used for growth of large diameter crystals of GaP, InP and GaAs is presented. Crystal properties and characteristic features are discussed to illustrate advantages and disadvantages of the vertical Bridgman-type growth techniques. 22 refs., 5 figs. more
Date: July 1, 1990
Creator: Bourret, E.D.
Partner: UNT Libraries Government Documents Department
open access

Characterization of Nb-Ti superconductors with artificial pinning structures

Description: A series of multifilamentary APC Nb-Ti superconductors have been made with Nb added as a normal second phase to provide flux pinning centers. Two compositions, 12.5% vol % and 25 vol % Nb in Nb-Ti, have fabricated into multifilamentary composites using two different fabrication methods. One method used hot isostatic compaction and hot extrusion thoughout the processing. The other method (bundle-and-draw process) discontinued all hot processing at an intermediate level. While the J{sub c} values… more
Date: June 1, 1990
Creator: Dietderich, D. R. & Scanlan, R. M.
Partner: UNT Libraries Government Documents Department
open access

Technological challenges of third generation synchrotron radiation sources

Description: New third generation'' synchrotron radiation research facilities are now in construction in France, Italy, Japan, Taiwan and the USA. Designs for such facilities are being developed in several other countries. Third generation facilities are based on storage rings with low electron beam emittance and space for many undulator magnets to produce radiation with extremely high brightness and coherent power. Photon beam from these rings will greatly extend present research capabilities and open up n… more
Date: January 1, 1990
Creator: Cornacchia, M. & Winick, H.
Partner: UNT Libraries Government Documents Department
open access

Particle correlations in JACEE (Japanese-American Cooperative Emulsion Experiment) nucleus-nucleus collisions

Description: Correlations in the production of charged particles and photons can be examined in detail in the central and forward rapidity range using high multiplicity ({ge}100 charged tracks) events from JACEE emulsion chambers. Results are presented on several forms of correlations studies. 9 refs., 2 figs.
Date: January 1, 1990
Partner: UNT Libraries Government Documents Department
open access

DEPOT: Database for electronics parts and other things

Description: DEPOT has been developed to provide tracking for the Stanford Linear Collider (SLC) control system equipment. For each piece of equipment entered in the database, a complete service, maintenance, modification, certification, location history, and, optionally, a radiation exposure history, can be maintained. To facilitate data entry accuracy, efficiency, and consistency, barcoding technology has been used extensively. DEPOT has been an important tool in improving the reliability of the microsyst… more
Date: January 1, 1990
Creator: Logg, C.A.; Clancey, P.W. & Crane, G.
Partner: UNT Libraries Government Documents Department
open access

A 40 mm bore quadrupole magnet for the SSC

Description: A 40 mm bore quadrupole magnet design, called QC'', has been made for the SSC with the following parameters: 208 T/m gradient at 6500A, 2-layer cos 2 {theta}'' winding arrangement with 30 strand cable and one spacer wedge per coil. Structural support is provided by self-supporting interlocking collars; two types of symmetrical laminations are pre-assembled into collar packs for ease of assembly. This paper will describe the design of a prototype quadrupole magnet for the SSC and preliminary tes… more
Date: September 1, 1990
Creator: Taylor, C.E.; Barale, P.; Caspi, S.; Dell'Orco, D.; Fritz, D.; Gilbert, W.S. et al.
Partner: UNT Libraries Government Documents Department
open access

Solidification/stabilization of technetium in cement-based grouts

Description: Mixed low-level radioactive and chemically hazardous process treatment wastes from the Portsmouth Gaseous Diffusion Plant are stabilized by solidification in cement-based grouts. Conventional portland cement and fly ash grouts have been shown to be effective for retention of hydrolyzable metals (e.g., lead, cadmium, uranium and nickel) but are marginally acceptable for retention of radioactive Tc-99, which is present in the waste as the highly mobile pertechnate anion. Addition of ground blast … more
Date: January 1, 1990
Creator: Gilliam, T. M.; Bostick, W. D.; Spence, R. D.; Shoemaker, J. L. (Oak Ridge National Lab., TN (USA); Oak Ridge Gaseous Diffusion Plant, TN (USA); Oak Ridge National Lab., TN (USA) et al.
Partner: UNT Libraries Government Documents Department
open access

Mechanical and electromagnetic analysis of 50 millimeter designs for the SSC dipole

Description: Several designs for the Superconducting Super Collider dipole magnet have been analyzed. This note discusses the mechanical and electromagnetic features of each design. Electromagnetic and Mechanical analyses were performed using hand, computer programs and finite element techniques to evaluate the design. 10 refs., 6 figs., 3 tabs.
Date: September 1, 1990
Creator: Jayakumar, J.; Leung, K.; Nobrega, F.; Orrell, D.; Sanger, P.; Snitchler, G. et al.
Partner: UNT Libraries Government Documents Department
open access

Kesterson crisis: Sorting out the facts

Description: The Kesterson Reservoir was planned as a regulating facility to control drainage water discharges into the San Joaquin-Scaramento River Delta from the San Luis Drain'' which was to dispose of salt-ladin agricultural water. Anticipated environmental impacts of the Kesterson operations focused almost exclusively on problems related to seepage and water-logging of nearby lands. Reuse of drainage water for wetlands focused on excessive salinity. Drainage water entered the reservoir in 1978. By 1983… more
Date: July 1, 1990
Creator: Benson, S.M. (Lawrence Berkeley Lab., CA (United States)); Delamore, M. & Hoffman, S. (Bureau of Reclamation, Sacramento, CA (United States). Mid-Pacific Region)
Partner: UNT Libraries Government Documents Department
open access

Nonadiabatic geometric phases of multiphoton transitions in dissipative systems and spin-j systems

Description: We present new developments in nonadiabatic geometric phases along two lines for systems undergoing changes of quantum state in intense fields. We first present a geometric representation of the non-Hermitian Schrodinger equation and introduce the notion of a complex multiphoton Aharonov-Anandan (AA) phase associated with dissipative two-level systems driven by periodic fields. The concept is further extended to include field modulation effects. We then develop the AA phase for spin-j systems i… more
Date: January 1, 1990
Creator: Layton, E.G. & Chu, Shih-I.
Partner: UNT Libraries Government Documents Department
open access

Inclusive quasielastic and deep inelastic electron scattering at high energies

Description: With high electron energies a kinematic regime can be reached where it will be possible to separate quasielastic and deep inelastic scattering. We present a short description of these processes which dominate the inclusive spectrum. Using the highest momentum transfer data available to guide our estimates, we give the kinematic requirements and the cross sections expected. These results indicate that inclusive scattering at high q has a yet unfilled potential. 18 refs., 13 figs.
Date: January 1, 1990
Creator: Day, D.B.
Partner: UNT Libraries Government Documents Department
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