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Influence of extrinsic crack deflection and delamination mechanisms on the cryogenic toughness of aluminum-lithium alloy 2090: Behavior in plate (T81) vs sheet (T83) material

Description: Cryogenic strength-toughness relationships are examined in 1.6-mm- thick sheet of commercial 2090-T8 aluminum-lithium alloy, and results compared with behavior in 12.7-mm-thick rolled plate. Unlike the significant increase in L-T fracture toughness exhibited by thick place sections at cryogenic temperatures, the thin sheet (of normally similar composition and microstructure) shows a marked decrease in toughness between 298 and 77 K. Such contrasting observations are attributed primarily to the … more
Date: February 1, 1989
Creator: Venkateswara Rao, K. T. & Ritchie, R. O.
Partner: UNT Libraries Government Documents Department
open access

An alternate end design for SSC dipoles

Description: Experience in the SSC dipole program has shown that fabrication of cylindrical coil ends is difficult. Cable stiffness requires large forces to maintain the proper position of the conductors in the end during winding. After winding, the coil ends remain distorted nd significant motion of the need conductors is required to force the coil end into the molding cavity. Local mechanical stresses are high during this process and extra pieces of insulation are required to prevent turn-to-turn shorts f… more
Date: February 1, 1989
Creator: Peters, C.; Caspi, S. & Taylor, C.
Partner: UNT Libraries Government Documents Department
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Optical data transmission at the superconducting super collider

Description: Digital and analog data transmissions via fiber optics for the Superconducting Super Collider have been investigated. The state of the art of optical transmitters, low loss fiber waveguides, receivers and associated electronics components are reviewed and summarized. Emphasis is placed on the effects of the radiation environment on the performance of an optical data transmission system components. Also, the performance of candidate components of the wide band digital and analog transmission sys… more
Date: February 1, 1989
Creator: Leskovar, B.
Partner: UNT Libraries Government Documents Department
open access

Low energy p p physics

Description: A detailed investigation of proton-antiproton interactions at low energy has become feasible with the commissioning of the LEAR facility in 1983. We shall shortly review the status of {bar p}p annihilation at rest and the physics motivations for second generation experiments with the Crystal Barrel detector. This type of detector would be adequate for the study of both Kp and {bar p}p interactions on an extracted beam of the KAON Factory. We shall conclude with a few remarks on the physics oppo… more
Date: February 1, 1989
Creator: Amsler, C.; Crowe, K. (Zurich Univ. (Switzerland). Inst. fuer Physik & Lawrence Berkeley Lab., CA (USA))
Partner: UNT Libraries Government Documents Department
open access

The search for a heavy Higgs boson

Description: Theoretical limits on the mass of the Higgs boson from vacuum stability and perturbative unitarity are examined. Search techniques for heavy Higgs bosons, M/sub H/ > 200 GeV, are also reviewed. 8 refs., 5 figs.
Date: February 1, 1989
Creator: Dawson, S.
Partner: UNT Libraries Government Documents Department
open access

Rollfix---An adiabatic roll transition for the SLC (Stanford Linear Collider) Arcs

Description: The SLC Arcs were rolled at achromat boundaries to follow the terrain of the SLAC site. This makes the linear optics sensitive to systematic gradient errors, from which severe cross-plane coupling effects may arise. As a partial correction, a smoother roll transition was introduced which relieves much of this sensitivity. We present an evaluation of this scheme and report on the observed improvements. 18 refs., 10 figs.
Date: February 1, 1989
Creator: Bambade, P.; Brown, K.; Fieguth, T.; Hutton, A.; Ritson, D.; Sands, M. et al.
Partner: UNT Libraries Government Documents Department
open access

Transverse energy and multiplicity from heavy ion collisions at 200 A GeV

Description: The successful acceleration of light ions at the CERN SPS and at the Brookhaven AGS opened the exciting field of ultra-relativistic heavy ion collisions for systematic studies. The first experiments were designed mainly to survey the reactions and to establish the essential features of the collisions. In this paper results from the WA80 experiment on transverse energy and charged particle multiplicity are reported. These two quantities are determined by most of the experiments and can be used t… more
Date: February 1, 1989
Creator: Ritter, H. G.; Albrecht, R.; Awes, T. C.; Baktash, C.; Beckmann, P.; Berger, F. et al.
Partner: UNT Libraries Government Documents Department
open access

Development of superconducting strand and cable with improved properties for use in SSC (Superconducting Super Collider) magnets

Description: The critical current requirement for the NbTi superconductor strand was set at 2750 A/mm/sup 2/ (5 T, 4.2 K) in the SSC Conceptual Design, compared with a value of 1800 A/mm/sup 2/ which was specified for the strand used in the Tevatron dipoles. In addition, a filament diameter of 5 ..mu..m, instead of the 9 ..mu..m diameter used in the Tevatron, was chosen to reduce field distortion at injection. In order to meet the requirements for field homogeneity, the dimensional requirements for both str… more
Date: February 1, 1989
Creator: Scanlan, R. M.
Partner: UNT Libraries Government Documents Department
open access

Strangeness production in nucleus-nucleus collisions: Experimental summary

Description: Rather than attempt to give a complete review of strangeness production in all kinds of experiments, I will dwell on the most interesting and promising aspects of the experimental results from nucleus-nucleus (A + A) experiments, using p + p//bar p/ + p and p + A//bar p/ + A data only as reference when needed. In this paper I will try: to identify the important features of the reaction mechanism; to understand the mechanisms; to learn about quark-gluon plasma formation by comparing nucleus-nucl… more
Date: February 1, 1989
Creator: Odyniec, G.
Partner: UNT Libraries Government Documents Department
open access

A CP violation and rare kaon decay experiment at Fermilab

Description: The E731 collaboration at Fermilab has collected enough K ..-->.. 2..pi.. events to give a statistical error of approx.0.5 /times/ 10/sup /minus/3/ on the CP violation parameter epsilon'/epsilon. Improvements have been made to reduce the systematic error. The experiment is also sensitive to many rare decays, and it set a new limit on the branching ratio of K/sub L/ ..-->.. ..pi../sup 0/e/sup +/e/sup /minus//, < 4.2 /times/ 10/sup /minus/8/ (90% CL). 10 refs., 15 figs., 1 tab.
Date: February 1, 1989
Creator: Yamanaka, Taku
Partner: UNT Libraries Government Documents Department
open access

A large superconducting detector magnet without an iron return path

Description: This paper describes a detector magnet which returns flux between the coils rather than through an iron return path. This actively shielded, uniform field 2 T magnet can be fabricated in separate parts which can be manufactured on the SSC site. This magnet can be built so that central field is uniform enough to permit a TPC detector to be used without iron poles. The field outside of the coil can be made to fall of as R/sup /minus/N/ power where N approaches 9. A major advantage of the magnet d… more
Date: February 1, 1989
Creator: Green, Michael A.
Partner: UNT Libraries Government Documents Department
open access

Combined Microstructure X-Ray Optics

Description: Multilayers are man-made microstructures which vary in depth and are now of sufficient quality to be used as x-ray, soft x-ray and extreme ultraviolet optics. Gratings are man-made in plane microstructures which have been used as optic elements for most of this century. Joining of these two optical microstructures to form combined microstructure optical microstructures to form combined microstructure optical elements has the potential for greatly enhancing both the throughput and the resolution… more
Date: February 1, 1989
Creator: Barbee, T. W., Jr.
Partner: UNT Libraries Government Documents Department
open access

On the re-acceleration of bunched beams

Description: We examine the re-acceleration of a bunched beam through a linear induction accelerator (LIA) cavity, with attention to the energy lost through coupling to the TM modes of the structure. We find that the energy lost at 1 kA peak current is a small fraction of the boost which the LIA is designed to impart. We discuss implications for a Relativistic Klystron or Free Electron Laser (FEL) version of the Two-Beam Accelerator (TBA). 18 refs., 5 figs., 1 tab.
Date: February 1, 1989
Creator: Whittum, D. H.; Sessler, A. M.; Craig, G. D.; DeFord, J. F. & Yu, David U. L.
Partner: UNT Libraries Government Documents Department
open access

Waste package performance assessment for the Yucca Mountain Project

Description: We completed a first cycle of model development from a specification to a computer program, PANDORA-1, for long-term performance assessment of waste packages. The model for one waste package at a time incorporates processes specific to the unsaturated environment at the proposed Yucca Mountain, NV, site. PANDORA-1 models the most likely processes and several modes of waste alteration and release. The development identified information needs for future models; many processes, local details, and … more
Date: February 1, 1989
Creator: O'Connell, W. J.; Lappa, D. A. & Thatcher, R. M.
Partner: UNT Libraries Government Documents Department
open access

Z/sup 0/ physics at the SLC

Description: This paper discusses the following topics: the standard model and its application to e/sup +/e/sup /minus// ..-->.. Z/sup 0/ ..-->.. f /bar f/; detector requirements; the upgraded MARKII detector; the physics measurements; searching for the top quark; is there a fourth generation.; Searching for Higgs scalars; and physics beyond the minimal standard model. 13 refs., 34 figs., 11 tabs.
Date: February 1, 1989
Creator: Dorfan, J. M.
Partner: UNT Libraries Government Documents Department
open access

The search for charged-lepton specific forces and the PEGASYS facility

Description: This paper discusses the electroproduction of lepton pairs as a method of searching for a charged-lepton specific force, and as a general method of searching for deviations from conventional quantum electrodynamics. The use of the PEGASYS facility for these purposes is briefly described. Search possibilities in other energy ranges are noted. 22 refs., 11 figs.
Date: February 1, 1989
Creator: Perl, Martin L.
Partner: UNT Libraries Government Documents Department
open access

The dynamical behavior of classifier systems

Description: Classifier systems are quite complicated, in terms of both their components and behavior. This complexity is understandable given the wide spectrum of activity they are intended to model. Unfortunately, the complexity of these systems also makes it difficult to understand them analytically. Previous analysis has focused on specific components of the classifier system, for example, the genetic algorithm or the bucket brigade. The lack of a unified theory has led users of these systems to rely on… more
Date: February 10, 1989
Creator: Forrest, S. & Miller, J.H.
Partner: UNT Libraries Government Documents Department
open access

Observation of excited H/sup 0/ atoms produced by relativistic H/sup /minus// ions in carbon and formvar foils

Description: We have measured the relative yield of several low-lying excited states of neutral hydrogen atoms produced by the passage of 226-MeV and 581-MeV H/sup /minus// ions through thin carbon foils and a tilted formvar foil. The relative yields of H/sup /minus///sub /asterisk//(n = 2,3, 4) were measured for 17 different carbon foils ranging in thickness from 662 /angstrom/ to 5386 /angstrom/ at 581 MeV. The relative yield of H/sup 0//sup /asterisk//(n = 2) was also measured for these carbon foils at 2… more
Date: February 8, 1989
Creator: Mohagheghi, A. H.; Bryant, H. C.; Harris, P. G.; Tang, C. Y.; Quick, C. R.; Reeder, R. A. et al.
Partner: UNT Libraries Government Documents Department
open access

Development of CRID (Cerenkov Ring Imaging Detector) single electron wire detector

Description: We describe the R and D effort to define the design parameters, method of construction and experimental results from the single electron wire detectors. These detectors will be used for particle identification using the Cerenkov Ring Imaging techniques in the SLD experiment at SLAC. We present measurements of pulse heights for several gases as a function of gas gain, charge division performance on a single electron signal using both 7 /mu/m and 33 /mu/m diameter carbon wires, photon feedback in… more
Date: February 1, 1989
Creator: Aston, D.; Bean, A.; Bienz, T.; Bird, F.; Caldwell, D.; Cavalli-Sforza, M. et al.
Partner: UNT Libraries Government Documents Department
open access

High speed switching in gases

Description: A fast, efficient and reliable switch is the basic ingredient of a pulse power accelerator. Two switches have been proposed so far: the solid state switch, and the vacuum photodiode switch. The solid state version has been tested to some extent, albeit at low (few kilovolts) level, with risetime around 10 ps in the radial line transformer configuration. The vacuum photodiode is being investigated by Fisher and Rao at Brookhaven National Laboratory. Common to both switches is the need of a short… more
Date: February 1, 1989
Creator: Cassell, R.E. & Villa, F.
Partner: UNT Libraries Government Documents Department
open access

Recent results on S = /minus/3 baryon spectroscopy from the LASS (Large Aperture Superconducting Solenoid) spectrometer

Description: Data demonstrating the existence of two ..cap omega../sup */minus// resonances produced in K/sup /minus//p interactions at 11 GeV/c in the LASS spectrometer are presented. The first state is seen in the ..xi../sup */degree//minus// decay channel with mass 2253 +- 13 MeV/c/sup 2/ and width 81 +- 38 MeV/c/sup 2/, and the second in the ..cap omega../sup /minus//..pi../sup +/..pi../sup /minus// system with mass 2474 +- 12 and width 72 +- 33 MeV/c/sup 2/. Inclusive cross sections corresponding to th… more
Date: February 1, 1989
Creator: Aston, D.; Awaji, N.; Bienz, T.; Bird, F.; D'Amore, J.; Dunwoodie, W. et al.
Partner: UNT Libraries Government Documents Department
open access

Fermilab R and D test facility for SSC (Superconducting Super Collider) magnets

Description: The test facility used for R and D testing of full scale development dipole magnets for the SSC is described. The Fermilab Magnet Test Facility, originally built for production testing of Tevatron magnets, has been substantially modified to allow testing also of SSC magnets. Two of the original six test stands have been rebuilt to accommodate testing of SSC magnets at pressures between 1.3 Atm and 4 Atm and at temperatures between 1.8 K and 4.8 K and the power system has been modified to allow … more
Date: February 1, 1989
Creator: Strait, J.; Bleadon, M.; Hanft, R.; Lamm, M.; McGuire, K.; Mantsch, P. et al.
Partner: UNT Libraries Government Documents Department
open access

An industrial cabling machine for the SSC

Description: The SSC project will need the manufacturing of some 25,000 kilometers of keystoned flat cable. The technical specifications of the various cables to be produced are the result of five years of research and development work at LBL. An experimental cable machine was built and run in the laboratory; many improvements were implemented and tested. Semi-industrial production of the various cables was performed, and the resulting cables were used and tested in the one-meter model magnets and 17.5 mete… more
Date: February 1, 1989
Creator: Royet, J.; Armer, R.; Hannaford, R. & Scanlan, R.
Partner: UNT Libraries Government Documents Department
open access

A new approach to tracer transport analysis: From fracture systems to strongly heterogeneous porous media

Description: Many current development and utilization of groundwater resources include a study of their flow and transport properties. These properties are needed in evaluating possible changes in groundwater quality and potential transport of hazardous solutes through the groundwater system. Investigation of transport properties of fractured rocks is an active area of research. Most of the current approaches to the study of flow and transport in fractured rocks cannot be easily used for analysis of tracer … more
Date: February 1, 1989
Creator: Tsang, Chin-Fu
Partner: UNT Libraries Government Documents Department
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