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0. 9 a Gev /sup 238/U on /sup 238/U collisions in the LBL streamer chamber. Appendix A

Description: Charged particle exclusive data for high multiplicity U on U events are reported. Analyses are based on comparison with Cugnon's intranuclear cascade model, and the explosion-evaporation simulation of Fai and Randrup. The azimuthal structure of the observed events shows evidence of collective flow. The widely used flow angle methodology proves to be relatively insensitive to collective effects under the conditions of the present experiment. An isotropic pattern of ejectile emission is not reach… more
Date: January 1, 1984
Creator: Fung, S.Y.; Beavis, D.; Gorn, W.; Keane, D.; Liu, Y.M.; Poe, R.T. et al.
Partner: UNT Libraries Government Documents Department
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3-D treatment of convective flow in the earth's mantle

Description: A three-dimensional finite-element method is used to investigate thermal convection in the earth's mantle. The equations of motion are solved implicitly by means of a fast multigrid technique. The computational mesh for the spherical problem is derived from the regular icosahedron. The calculation described use a mesh with 43,554 nodes and 81,920 elements and were run on a Cray X. The earth's mantle is modeled as a thick spherical shell with isothermal, free-slip boundaries. The infinite Prandt… more
Date: May 1, 1984
Creator: Baumgardner, J.R.
Partner: UNT Libraries Government Documents Department
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5 K neutron irradiation and thermal cycling of NbTi superconductors

Description: Simulation experiments of magnet operating conditions in a fusion reactor are reported. After approximately half of the lifetime dose the results on a variety of NbTi superconductors show moderate changes of the critical current density j/sub c/ (approx. 10%), the percentage change of j/sub c/ is always larger at high fields (8 T) than at 5 T. After a rapid initial change the resistivity ratios of the Cu-stabilizer are found to decrease only slowly with increasing neutron fluence.
Date: May 1, 1984
Creator: Hahn, P.; Hoch, H.; Weber, H. W.; Birtcher, R. C. & Brown, B. S.
Partner: UNT Libraries Government Documents Department
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6. 5 Tesla SSC lattice example

Description: This note presents an example SSC collider lattice for 20 TeV proton beams using 6.5 Tesla double bore magnets, six collision points, and anti-symmetric insertions.
Date: January 1, 1984
Creator: Garren, A.A.
Partner: UNT Libraries Government Documents Department
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O(18) revived

Description: We present an O(18) theory which is pertubatively unifiable and which accounts for the absence of right-handed families in the low-energy world. The model gives rise to dramatic predictions for proton decay and for the Z/sup 0/ width.
Date: August 1, 1984
Creator: Bagger, J.; Dimopoulos, S. & Masso, E.
Partner: UNT Libraries Government Documents Department
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25. mu. A pulsed polarized H/sup -/ ion source

Description: A Haeberli-type pulsed polarized negative hydrogen source has been brought into operation at the BNL Alternating Gradient Synchrotron. It operates reliably at beam currents sometimes as high as 25 ..mu..A and 20 keV in beam pulses of 500 ..mu..sec with approximately 75% polarization. These beam intensities are about an order of magnitude higher than the original Haeberli source built at the University of Wisconsin. This improvement is caused by the higher densities of both the atomic hydrogen b… more
Date: January 1, 1984
Creator: Alessi, J.; Kponou, A. & Sluyters, T.
Partner: UNT Libraries Government Documents Department
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40 mm bore Nb-Ti model dipole magnet

Description: Preliminary R and D has been started on magnets for a next-generation high-energy-physics accelerator, the 20 TeV Superconducting Supercollider (SSC). One design now being developed at LBL is described in this paper. The design is based on two layers of flattened Nb-Ti cable, a 40 mm ID winding with flared ends, and an operating field of 6.5 T. Experimental results are presented on several one-meter-long models tested at both He I and He II temperature. Measurement of field, residual magnetizat… more
Date: September 10, 1984
Creator: Taylor, C.; Gilbert, W.; Hassenzahl, W.; Meuser, R.; Peters, C.; Rechen, J. et al.
Partner: UNT Libraries Government Documents Department
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60 GHz, 200 kW CW gyrotron with high output mode purity

Description: For the first time, a Varian 60 GHz gyrotron, designed specifically to generate microwaves in a single output mode, has been operated at power levels up to 200 kW CW. High output mode purity is required for the efficient utilization of gyrotrons as high power microwave sources for electron cyclotron resonance heating (ECRH) in magnetic fusion plasmas. Using mode-specific directional couplers, measurements of the output mode content indicated that greater than 95% of the microwave output was in … more
Date: January 1, 1984
Creator: Jory, H.; Felch, K.; Bier, R.; Fox, L.; Huey, H.; Ives, L. et al.
Partner: UNT Libraries Government Documents Department
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100 MHz fiber optic single transient gamma ray detection system

Description: A fiber optic system has been developed to measure single transient gamma rays. The gamma ray signature is converted to light by the Cerenkov process in a 20 cm length of radiation resistant optical fiber. The signal is transmitted over 1 km of optical fiber and detected by state-of-the-art, 175 MHz analog receivers. The receivers are based on silicon PIN detectors with transimpedance hybrid amplifiers and two stages of power amplification. The dc coupled receivers have less than 2% distortion … more
Date: January 1, 1984
Creator: Ogle, J. W.; Smith, R. C.; Ward, M.; Ramsey, R. & Hollabaugh, J.
Partner: UNT Libraries Government Documents Department
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650 mm long liquid hydrogen target for use in a high intensity electron beam

Description: This paper describes a 650 mm long liquid hydrogen targetr constructed for use in the high intensity electron beam at the Stanford Linear Accelerator Center (SLAC). The main design problem was to construct a target that would permit the heat deposited by the electron beam to be removed rapidly without boiling the hydrogen so as to maintain constant target density for optimum data taking. Design requirements, cosntruction details and operating experience are discussed.
Date: February 1, 1984
Creator: Mark, J.W.
Partner: UNT Libraries Government Documents Department
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3081/E processor

Description: The 3081/E project was formed to prepare a much improved IBM mainframe emulator for the future. Its design is based on a large amount of experience in using the 168/E processor to increase available CPU power in both online and offline environments. The processor will be at least equal to the execution speed of a 370/168 and up to 1.5 times faster for heavy floating point code. A single processor will thus be at least four times more powerful than the VAX 11/780, and five processors on a system… more
Date: April 1, 1984
Creator: Kunz, P. F.; Gravina, M.; Oxoby, G.; Rankin, P.; Trang, Q.; Ferran, P. M. et al.
Partner: UNT Libraries Government Documents Department
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3D calculations of the Superconducting Super Collider (SSC) 3 Tesla magnet

Description: A 20 TeV Superconducting Super Collider (SSC) proton accelerator is being proposed by the High Energy Physics Community. One proposal would consist of a ring of magnets 164 km in circumference with a field strength of 3 Tesla and would cost 2.7 billion dollars. The magnet consists of stacked steel laminations with superconducting coils. The desired field uniformity is obtained for all fields from 0.2 to 3 Tesla by using three (or more) different pole shapes. These three different laminations ar… more
Date: January 1, 1984
Creator: Lari, R.J.
Partner: UNT Libraries Government Documents Department
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Ab initio calculations of the optical properties of ions in glass

Description: There is interest in the optical properties of ions in insulating glasses for various applications. This paper addresses the task of predicting optical properties of ions in glass from first principles given only the physics of the constituent atoms. The prospects for developing such ab initio-computation procedures are gleaned from examining the progress made in understanding the properties of dopant ions in crystals. It is probable that in 20 years, there will be reliable procedures for predi… more
Date: August 1, 1984
Creator: Weber, M. J.
Partner: UNT Libraries Government Documents Department
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Absolute calibration technique for spontaneous fission sources

Description: An absolute calibration technique for a spontaneously fissioning nuclide (which involves no arbitrary parameters) allows unique determination of the detector efficiency for that nuclide, hence of the fission source strength.
Date: January 1, 1984
Creator: Zucker, M.S. & Karpf, E.
Partner: UNT Libraries Government Documents Department
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Absolute dipole gamma-ray strength functions for /sup 176/Lu

Description: We have derived absolute dipole strength-function information for /sup 176/Lu from an average resonance capture study of /sup 175/Lu with 2-keV neutrons, and from neutron capture cross-section measurements with neutrons from 30 keV to about 1 MeV. We found that we needed to increase our previous estimate of the relative M1/E1 strengths near 5 MeV by a factor of 3, and to revise downward the absolute magnitude of our E1 strength function. We accomplished the latter, while still maintaining conti… more
Date: August 29, 1984
Creator: Gardner, D. G.; Gardner, M. A. & Hoff, R. W.
Partner: UNT Libraries Government Documents Department
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Absolute dipole gamma-ray strength functions for /sup 176/Lu. Supplement

Description: We have derived absolute dipole strength-function information for /sup 176/Lu from an average resonance capture study of /sup 175/Lu with 2-keV neutrons and from neutron capture cross-section measurements with neutrons from 30 keV to about 1 MeV. We found that we needed to increase our previous estimate of the relative M1/E1 strengths near 5 MeV by a factor of 3 and to revise downward the absolute magnitude of our E1 strength function. We accomplished the latter, while still maintaining continu… more
Date: October 16, 1984
Creator: Gardner, D. G.; Gardner, M. A. & Hoff, R. W.
Partner: UNT Libraries Government Documents Department
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Absolute subcriticality measurement without calibration and detection efficiency dependence by the /sup 252/Cf source-driven noise method

Description: The /sup 252/Cf-source-driven noise analysis method determines the subcriticality of a system containing fissionable material from the ratio of cross power spectral densities between the detectors that detect particles from the fission process and between these detectors and an ionization chamber containing a spontaneously fissioning neutron source which provides neutrons to induce fission in the system. This method has two advantages: (1) a calibration is not required and thus subcriticality c… more
Date: January 1, 1984
Creator: Mihalczo, J. T. & King, W. T.
Partner: UNT Libraries Government Documents Department
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Absorber coatings' degradation

Description: This report is intended to document some of the Los Alamos efforts that have been carried out under the Department of Energy (DOE) Active Heating and Cooling Materials Reliability, Maintainability, and Exposure Testing program. Funding for these activities is obtained directly from DOE although they represent a variety of projects and coordination with other agencies. Major limitations to the use of solar energy are the uncertain reliability and lifetimes of solar systems. This program is aimed… more
Date: January 1, 1984
Creator: Moore, S.W.
Partner: UNT Libraries Government Documents Department
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Acceleration of high charge density electron beams in the SLAC linac

Description: The SLAC Linear Collider (SLC) will require both electron and positron beams of very high charge density and low emittance to be accelerated to about 50 GeV in the SLAC 3-km linac. The linac is in the process of being improved to meet this requirement. The program to accelerate an electron beam of high charge density through the first third of the SLC linac is described and the experimental results are discussed. 7 references, 5 figures.
Date: January 1984
Creator: Sheppard, J. C.; Clendenin, J. E.; Jobe, R. K.; Lueth, V. G.; Millich, A.; Ross, M. C. et al.
Partner: UNT Libraries Government Documents Department
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Acceleration of polarized protons at the AGS

Description: Spin physics in the past has provided an acid test of many models and theories and over the last decade has revealed new and unexpected phenomena to confront present day theories. This work received great impetus from the experiments at the ZGS, where for the first time multi-GeV polarized beams became available. This, in conjunction with polarized targets, allowed the complete specification of the initial quantum states in high energy proton-proton interactions and led to many startling new re… more
Date: May 30, 1984
Creator: Ratner, L .G.
Partner: UNT Libraries Government Documents Department
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Accelerator-based atomic physics experiments with photon and ion beams

Description: Accelerator-based atomic physics experiments at Brookhaven presently use heavy-ion beams from the Dual MP Tandem Van de Graaff Accelerator Facility for atomic physics experiments of several types. Work is presently in progress to develop experiments which will use the intense photon beams which will be available in the near future from the ultraviolet (uv) and x-ray rings of the National Synchrotron Light Source (NSLS). Plans are described for experiments at the NSLS and an exciting development… more
Date: April 26, 1984
Creator: Johnson, B. M.; Jones, K. W. & Meron, M.
Partner: UNT Libraries Government Documents Department
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Accelerator-based plasma-wall interaction studies on the TEXTOR tokamak

Description: Deposition probes are commonly used to determine plasma edge characteristics in tokamaks. Such probes are frequently analyzed using accelerator-based techniques and can yield information on impurity fluxes, hydrogen fluxes and energies, and surface erosion rates in the plasma edge. Several types of deposition probes have been employed to investigate the plasma edge region of the TEXTOR tokamak in Juelich, FRG. TEXTOR is a moderate size tokamak (major radius = 1.75 m) that is capable of 2 to 3 s… more
Date: September 1, 1984
Creator: Zuhr, R.A.
Partner: UNT Libraries Government Documents Department
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Accelerator-colliders for relativistic heavy ions or in search of luminosity

Description: Some issues pertinent to the design of collider rings for relativistic heavy ions are presented. Experiments at such facilities are felt to offer the best chance for creating in the laboratory a new phase of subatomic matter, the quark-gluon plasma. It appears possible to design a machine with sufficient luminosity, even for the heaviest nuclei in nature, to allow a thorough exploration of the production conditions and decay characteristics of quark-gluon plasma.
Date: January 1, 1984
Creator: Young, G. R.
Partner: UNT Libraries Government Documents Department
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Accelerator mass spectrometry with a coupled tandem-linac system

Description: A coupled system provides higher energies, which allows one to extend AMS to hitherto untouched mass regions. Another important argument is that the complexity, although bothersome for the operation, increases the selectivity of detecting a particular isotope. The higher-energy argument holds for any heavy-ion accelerator which is capable of delivering higher energy than a tandem. The present use of tandem-linac combinations for AMS, rather than cyclotrons, linacs or combinations of these machi… more
Date: January 1, 1984
Creator: Kutschera, W.
Partner: UNT Libraries Government Documents Department
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