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Inclusive. eta. production in. tau. decays

Description: We have searched for inclusive eta production in tau decays using a sample of 2553 events of e{sup +}e{sup minus} {yields} {tau}{sup +}{tau}{sup minus} in the one-three topology. The data were taken with the High Resolution Spectrometer at {radical}s = 29 GeV. Our results are based on an analysis of the {pi}{sup +}{pi}{sup minus} invariant mass spectrum to find the narrow peak resulting from the decay sequence {tau} {yields} {eta}x and {eta} {yields} {pi}{sup +}{pi}{sup minus}{pi}{degree}. No c… more
Date: January 1, 1987
Creator: Abachi, S.; Akerlof, C.; Baringer, P.; Blockus, D.; Brabson, B.; Brom, J. M. et al.
Partner: UNT Libraries Government Documents Department
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Search for D/sup *//sup 0/. -->. D/sup +/. pi. /sup -/

Description: We report on a search for the decay mode D/sup *//sup 0/(2007) ..-->.. D/sup +/..pi../sup -/ using the High Resolution Spectrometer at PEP. Although this decay is kinematically forbidden for the central mass value, it can occur through the natural width of the D/sup *//sup 0/. The D/sup +/ was reconstructed in the K/sup -/..pi../sup +/..pi../sup +/ decay mode. The mass difference distribution (K/sup -/..pi../sup +/..pi../sup +/..pi../sup +/) - (K/sup -/..pi../sup +/..pi../sup -/), which shows n… more
Date: January 1, 1987
Creator: Abachi, S.; Akerlof, C.; Baringer, P.; Blockus, D.; Brabson, B.; Brom, J.M. et al.
Partner: UNT Libraries Government Documents Department
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Measurement of Energy and Charged Particle Emission in the Central Rapidity Region from O + A and p + A collisions at 14. 5 GeV/c per Nucleon and Preliminary Results from Si + A collisions

Description: The first data from a 160 beam of total energy 232 GeV at the BNL Tandem-AGS are discussed. Preliminary results from a /sup 28/Si beam of total energy 406 GeV are also shown. The full complement of E-802, including a magnetic spectrometer, was used for the /sup 28/Si measurement. A different experimental arrangement was used for 160. Comparison measurements with proton beams are presented for both configurations. 12 refs., 12 figs.
Date: January 1, 1987
Creator: Abbott, T.; Akiba, Y.; Alburger, D.; Beavis, D.; Betts, R. R.; Bloomer, M. A. et al.
Partner: UNT Libraries Government Documents Department
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Preparing the radiation protection worker to meet multiple needs

Description: At the Oak Ridge National Laboratory (ORNL) the radiation protection worker aids in protecting personnel and their surrounding environment from the hazards of radiation. These individuals use their technical knowledge, skills, and abilities to survey and monitor various project-related activities. They must also provide guidance in project design, development, and implementation. These combined efforts assure that protective measures are taken in accordance with applicable standards. The ORNL p… more
Date: January 1, 1987
Creator: Abercrombie, J.S. & Thorpe, B.C.
Partner: UNT Libraries Government Documents Department
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Fast Energy and Energy Spectrum Feedback in the SLC Linac

Description: The energies and energy spectra of the positron and electron beams emerging from the SLC Linac must be carefully maintained so that the beams can be transported through the Arcs to the Final Focus without phase space dilution and also to specify the collision energy. A fastback system has been designed and constructed to control these parameters. The energies and energy spectra are measured nondestructively using position monitors and synchrotron radiation width monitors. The controls consist o… more
Date: January 1, 1987
Creator: Abrams, G. S.; Soderstrom, E.; Seeman, J. T.; Campisi, I. E.; Herrmannsfeldt, W.; Lee, M. et al.
Partner: UNT Libraries Government Documents Department
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IR laser excitation in molecules: Chaos and diffusive energy growth

Description: After a short review of a generic vibrational model of ir multiple-photon excitation, the model is generalized to include rotations. It is shown that the combination of chaotic dynamics and rotational averaging leads to fluence-dependent absorption which removes the sensitivity of the results to model-dependent parameters. The classical rotation-vibration dynamics observed in this model correlate very well with quantum intuition based on a molecule's P, Q, and R-branch structure and on the red-… more
Date: January 1, 1987
Creator: Ackerhalt, J. R. & Milonni, P. W.
Partner: UNT Libraries Government Documents Department
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Boundary-projection acceleration: A new approach to synthetic acceleration of transport calculations

Description: We present a new class of synthetic acceleration methods which can be applied to transport calculations regardless of geometry, discretization scheme, or mesh shape. Unlike other synthetic acceleration methods which base their acceleration on P1 equations, these methods use acceleration equations obtained by projecting the transport solution onto a coarse angular mesh only on cell boundaries. We demonstrate, via Fourier analysis of a simple model problem as well as numerical calculations of var… more
Date: January 1, 1987
Creator: Adams, M. L. & Martin, W. R.
Partner: UNT Libraries Government Documents Department
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A general topology, Godunov method

Description: A numerical technique that utilizes a general topology mesh is described. The method employs the arbitrary Lagrangian-Eulerian procedure and explicit, finite-volume, Godunov numerics. Material interfaces are resolved to eliminate fictitious mixing and nonphysical shear impedance. Cell-centered variables, including velocity, are used to provide consistent control volumes for the advection of mass, momentum, and energy, and to allow arbitrary slip between material regions. The computational mesh … more
Date: January 1, 1987
Creator: Addessio, F.; Cline, M. & Dukowicz, J.
Partner: UNT Libraries Government Documents Department
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Emittance growth in rippled solenoidal magnetic fields

Description: Emittance growth results due to accelerating gaps, and magnetic field gaps in induction accelerators. The analytic technique previously used to study electric field induced emittance growth for immersed source beams is extended to include solenoid fringing field effects in the present work. These results have application to industrial induction accelerators and to high brightness Free Electron Laser drivers. 1 ref., 2 figs.
Date: January 1, 1987
Creator: Adler, R.J.
Partner: UNT Libraries Government Documents Department
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A Search for Heavy Neutrino Decays in a Neutrino Beam

Description: Decay of heavy neutrinos ..nu../sub H/ ..-->.. ..nu..l..mu..e(l = e, ..mu..) has been searched for in the Brookhaven Alternting Gradient Synchrotron wide-band neutrino beam. Since no significant excess of such events was found, upper limits on the neutrino mixing matrix elements, absolute value of U/sub eH//sup 2/ and absolute value of U/sub ..mu..H//sup 2/ were obtained for the mass range of 180 to 500 MeV.
Date: January 1, 1987
Creator: Ahrens, L. A.; Aronson, S. H.; Gibbard, B. G.; Murtagh, M. J.; White, D. H.; Callas, J. L. et al.
Partner: UNT Libraries Government Documents Department
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Measurement of the Photon Structure Function F/sub 2//sup gamma/(x,Q/sup 2/) Between 10 less than or equal to Q/sup 2/ less than or equal to 60 GeV/sup 2/

Description: We present a measurement of the photon structure function F/sub 2//sup ..gamma../ in the reaction ee..-->..eeX for Q/sup 2/ in the range 10 < Q/sup 2/ < 60 GeV/sup 2/, using 285 multihadron events obtained with the TPC/Two-Gamma detector at PEP. The data have been corrected for detector effects using a regularized unfolding procedure. Using our previous low Q/sup 2/ measurements to estimate the hadronic component, we perform a QCD analysis at high Q/sup 2/ within the context of the regularisati… more
Date: January 1, 1987
Creator: Aihara, H.; Alston-Garnjost, M.; Avery, R. E.; Barbaro-Galtieri, A.; Barker, A. R.; Barnett, B. A. et al.
Partner: UNT Libraries Government Documents Department
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Latency differences and effects of selective attention to gratings in the central and right visual fields: II

Description: The goals were to examine the temporal sequence in which visual information (such as visual field, spatial frequency) are processed and to determine whether different neural sources are activated when such features are attended versus not attended. These issues are basic to current models of visual selective attention. 10 refs., 4 figs.
Date: January 1, 1987
Creator: Aine, C. J.; George, J. S. & Flynn, E. R.
Partner: UNT Libraries Government Documents Department
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Hydrogen speciation in hydrated layers on nuclear waste glass

Description: The hydration of an outer layer on nuclear waste glasses is known to occur during leaching, but the actual speciation of hydrogen (as water or hydroxyl groups) in these layers has not been determined. As part of the Nevada Nuclear Waste Storage Investigations Project, we have used infrared spectroscopy to determine hydrogen speciations in three nuclear waste glass compositions (SRL-131 & 165, and PNL 76-68), which were leached at 90{sup 0}C (all glasses) or hydrated in a vapor-saturated atmosph… more
Date: January 15, 1987
Creator: Aines, R. D.; Weed, H. C. & Bates, J. K.
Partner: UNT Libraries Government Documents Department
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Molecular and supramolecular orientation in conducting polymers

Description: Intrinsic anisotropy in electrical and optical properties of conducting polymers constitutes a unique aspect that derives ..pi..-electron delocalization along the polymer backbone and from the weak inter-chain interaction. To acquire such an intrinsic property, conducting polymers have to be oriented macroscopically and microscopically (at the chain level). A review of the various techniques, including stretch-alignment of the polymer and of precursor polymers, polymerization in ordered media, … more
Date: January 1, 1987
Creator: Aldissi, M.
Partner: UNT Libraries Government Documents Department
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Improved input representation for enhancement of neural network performance

Description: The performance of an associate memory network depends significantly on the representation of the data. For example, it has already been recognized that bipolar representation of neurons with -1 and +1 states out- perform neurons with on and off states of +1 and 0 respectively. This paper will show that a simple modification of the pattern vector to have zero bias will provide even more significant increase for the performance of an associative memory network. The higher order algorithm is used… more
Date: January 1, 1987
Creator: Aldrich, C. H.; An, Z. G.; Lee, K. & Lee, Y. C.
Partner: UNT Libraries Government Documents Department
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AGS preinjector improvement

Description: In 1984, a polarized H/sup -/ source was installed to permit the acceleration of polarized protons in the AGS, using a low current, 750 keV RFQ Linear Accelerator as the preinjector. This RFQ was designed by LANL and has proved to be quite satisfactory and reliable. In order to improve the reliability and simplify maintenance of the overall AGS operations, it has been decided to replace one of the two 750 keV Cockcroft-Waltons (C-W) with an RFQ. The design of a new high current RFQ has been car… more
Date: January 1, 1987
Creator: Alessi, J. G.; Brennan, J. M.; Brown, H. N.; Brodowski, J.; Gough, R.; Kponou, A. et al.
Partner: UNT Libraries Government Documents Department
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H/sup -/ source and beam transport experiments for a new RFQ

Description: A new RFQ preinjector is being built for the 200 MeV Linac at the AGS. For injection into this RFQ, a symmetric emittance has been obtained from a circular aperture magnetron H/sup -/ source. Transport studies are beginning to address possible problems with space charge or instabilities in the 35 keV line. A volume H/sup -/ source is being tested as an eventual replacement for the magnetron.
Date: January 1, 1987
Creator: Alessi, J. G.; Brennan, J. M.; Kponou, A. & Prelec, K.
Partner: UNT Libraries Government Documents Department
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State of the art in polarized proton sources

Description: Present day polarized H/sup +/ and H/sup -/ ion sources are reviewed by describing the performance of sources representative of each of the techniques being used. New ideas for producing higher intensities are then mentioned. Presently, pulsed H/sup +/-vector currents in the milliampere range, and H/sup -/-vector currents of hundreds of ..mu..A's, can be obtained.
Date: January 1, 1987
Creator: Alessi, J.G.
Partner: UNT Libraries Government Documents Department
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The relation of solar wind structure to hydromagnetic discontinuities

Description: High resolution ISEE-3 data have been used to examine the relative abundances of tangential (TD) vs rotational (RD) discontinuities in different types of solar wind flow. Three types of flow were examined; flow from coronal holes, sector boundary flow and transient flow. It has been found that coronal hole flow has substantially more discontinuities and a greater ratio of RD's to TD's than do the other types of flow. Discontinuities are least frequent in transient flows characterized by bidirec… more
Date: January 1, 1987
Creator: Alexander, C. J.; Neugebauer, M.; Smith, E. J. & Bame, S. J.
Partner: UNT Libraries Government Documents Department
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Rcra (Resource Conservation and Recovery Act) Waste Oversight: Lead

Description: Historically, in the nuclear industry, water, concrete, steel, and lead have been common materials used for radiation shielding purposes. Lead, a high-density material, is a very effective shield for gamma radiation and has been utilized extensively at the Oak Ridge National Laboratory (ORNL) in association with radioisotope production and nuclear research. During these activities, lead became an inherent part of the radioactive waste and was disposed of in massive quantities by land burial.
Date: January 1, 1987
Creator: Alexander, W. A.
Partner: UNT Libraries Government Documents Department
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Performance of the SLAC Linear Collider klystrons

Description: There are now 200 new, high power 5045 klystrons installed on the two-mile Stanford Linear Accelerator. Peak power per klystron averages over 63 MW. Average energy contribution is above 240 MeV per station. Electron beam energy has been measured as high as 53 GeV. Energy instability due to klystron malfunction is less than 0.2%. The installed klystrons have logged over one million operating hours with close to 20,000 klystron hours cumulative operating time between failures. Data are being accu… more
Date: January 1, 1987
Creator: Allen, M. A.; Fowkes, W. R.; Koontz, R. F.; Schwarz, H. D.; Seeman, J. T. & Vlieks, A. E.
Partner: UNT Libraries Government Documents Department
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Debugging Fortran on a shared memory machine

Description: Debugging on a parallel processor is more difficult than debugging on a serial machine because errors in a parallel program may introduce nondeterminism. The approach to parallel debugging presented here attempts to reduce the problem of debugging on a parallel machine to that of debugging on a serial machine by automatically detecting nondeterminism. 20 refs., 6 figs.
Date: January 1, 1987
Creator: Allen, T.R. & Padua, D.A.
Partner: UNT Libraries Government Documents Department
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What are the attributes of a good standard and associated criteria

Description: The Department of Energy (DOE) Standards and Criteria (S and C) provide the framework upon which Office of Security Evaluations (OSE) inspections of safeguards and security at DOE facilities are conducted. The S and C were created to assure that inspections are comprehensive, standardized to the extent possible and accurately reported in meaningful terms, and that assessments are objective. With these goals in mind, the desirable attributes of a standard and its associated criteria are relevanc… more
Date: January 1, 1987
Creator: Allentuck, J.
Partner: UNT Libraries Government Documents Department
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The Emittance and Brightness Characteristics of Negative Ion Sources Suitable for MeV Ion Implantation

Description: This paper provides the description and beam properties of ion sources suitable for use with ion implantation devices. Particular emphasis is placed on the emittance and brightness properties of state-of-the-art, high intensity, negative ion sources based on the cesium ion sputter principle. (WRF)
Date: January 1, 1987
Creator: Alton, G. D.
Partner: UNT Libraries Government Documents Department
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