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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 clear peak is observed and a 90% confidence upper limit on the process {tau} {yields} {eta}x of 2.1% is found. For decays {tau} {yields} {eta}{eta}x the 90% confidence upper limit is 1.3%. Our best limit on {tau} {yields} {eta}{eta}x is obtained from tau decay to five charged particles with a 90% confidence level upper limit of 0.5%.
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

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 no threshold enhancement, leads to a preliminary upper limit on the branching ratio of B/sub r/(D/sup *//sup 0/ ..-->.. D/sup +/..pi../sup -/) < 15% at 90% CL. This, in turn, corresponds to an upper limit on the D/sup *//sup 0/ width of 1.5 MeV/c/sup 2/ at 90% CL. 4 refs., 3 figs.
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

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

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 performance-based training program enhances the skills of the worker. The program incorporates job specific information on the diverse facilities and activities monitored with basic fundamentals of radiation protection. Successful completion of this program includes passing both a qualification exam and an on-the-job skills review. This paper details the structure of such a program and explains the strategies taken to reach the program's goals. 4 refs., 2 tabs.
Date: January 1, 1987
Creator: Abercrombie, J.S. & Thorpe, B.C.
Partner: UNT Libraries Government Documents Department

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 of rf phases in the Damping Rings, SLED timing, and rf amplitude. Theoretical aspects of the feedback process, algorithms, and operational experience are discussed.
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

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-shift of the vibrational absorption with excitation. The implication of these results for MPE experiments is discussed.
Date: January 1, 1987
Creator: Ackerhalt, J.R. & Milonni, P.W.
Partner: UNT Libraries Government Documents Department

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 various problems, that the simplest of these methods are unconditionally stable with spectral radius less than or equal toc/3 (c being the scattering ratio), for several different discretization schemes in slab geometry. 28 refs., 4 figs., 3 tabs.
Date: January 1, 1987
Creator: Adams, M.L. & Martin, W.R.
Partner: UNT Libraries Government Documents Department

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 is composed of arbitrary polygonal cells. The constraint of a fixed logical connectivity for the mesh is removed. Consequently, geometrical mesh limitations, which are responsible for inaccuracies and code failure during the evolution of region boundaries, are absent. Arbitrary boundaries can be resolved, and the mesh is capable of changing smoothly and rapidly from regions of high to low resolution. Lack of a coherent mesh orientation minimizes numerical anisotropy. A mesh rezoning approach, based on a dual triangulation and coupled with a global remapping algorithm, allows the mesh to evolve dynamically. 9 refs., 6 figs.
Date: January 1, 1987
Creator: Addessio, F.; Cline, M. & Dukowicz, J.
Partner: UNT Libraries Government Documents Department

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

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

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 regularisation scheme of Antoniadis and Grunberg. We obtain rather safe bounds on the value of the QCD scale parameter of 119 +- 34 < ..lambda../sub M-bar S-bar/ < 215 +- 55 MeV.
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

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

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 atmosphere at 202{sup 0}C (SRL-131 only). Hydroxyl groups were found in the surface layers of all the glasses. Molecular water was found in the surface of SRL-131 and PNL 76-68 glasses that had been leached for several months in deionized water, and in the vapor-hydrated sample. The water/hydroxyl ratio increases with increasing reaction time; molecular water makes up most of the hydrogen in the thick reaction layers on vapor-phase hydrated glass while only hydroxyl occurs in the least reacted samples. Using the known molar absorptivities of water and hydroxyl in silica-rich glass the vapor-phase layer contained 4.8 moles/liter of molecular water, and 0.6 moles water in the form hydroxyl. A 15 {mu}m layer on SRL-131 glass formed by leaching at 90{sup 0}C contained a total of 4.9 moles/liter of water, 2/3 of which was as hydroxyl. The unreacted bulk glass contains about 0.018 moles/liter water, all as hydroxyl. The amount of hydrogen added to the SRL-131 glass was about 70% of the original Na + Li content, not the 300% that would result from alkali=hydronium ion interdiffusion. If all the hydrogen is then assumed to be added as the result of alkali-H{sup +} interdiffusion, the molecular water observed may have formed from condensation of the original hydroxyl groups.
Date: January 15, 1987
Creator: Aines, R. D.; Weed, H. C. & Bates, J. K.
Partner: UNT Libraries Government Documents Department

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, i.e., in a liquid crystal solvent, and synthesis of liquid crystalline conducting polymers will be given. 29 refs.
Date: January 1, 1987
Creator: Aldissi, M.
Partner: UNT Libraries Government Documents Department

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 for the numerical simulation studies of this paper. To the lowest order this algorithm reduces to the Hopfield model for auto-associative memory and the bidirectional associative memory (BAM) for hetero-associative memory model respectively. 16 refs., 4 figs., 1 tabs.
Date: January 1, 1987
Creator: Aldrich, C.H.; An, Z.G.; Lee, K. & Lee, Y.C.
Partner: UNT Libraries Government Documents Department

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

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 carried out by LBL and is also being constructed there. This paper describes the preinjector improvement project, centered around that RFQ, which is underway at BNL.
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

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

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 bidirectional streaming of electrons. This leads us to the conclusion that meaningful studies of the velocity dependence of the rates of occurrence of different types of discontinuities must take the type of flow (coronal hole versus transient) into account. 7 refs., 3 figs., 1 tab.
Date: January 1, 1987
Creator: Alexander, C.J.; Neugebauer, M.; Smith, E.J. & Bame, S.J.
Partner: UNT Libraries Government Documents Department

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

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 accumulated on klystron operation and failure modes with failure signatures starting to become apparent. To date, no wholesale failure modes have surfaced that would impair the SLAC Linear Collider (SLC) program.
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

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

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 relevance, inspectability, and limited need for inspector judgement. 1 fig.
Date: January 1, 1987
Creator: Allentuck, J.
Partner: UNT Libraries Government Documents Department

Low-energy particle production and residual nuclei production from high-energy hadron-nucleus collisions

Description: The high-energy hadron-nucleus collision model, EVENTQ, has been modified to include a calculation of the excitation and kinetic energy of the residual compound nucleus. The specific purpose of the modification is to make it possible to use the model in the high-energy radiation transport code, HETC, which, in conjunction with MORSE, is used to transport the low energy particles. It is assumed that the nucleons in the nucleus move in a one-dimensional potential well and have the momentum distribution of a degenerate Fermi gas. The low energy particles produced by the deexcitation of the residual compound nucleus, and the final residual nucleus, are determined from an evaporation model. Comparisons of multiplicities and residual nuclei distributions with experimental data are given. The ''grey'' particles, i.e., charged particles with 0.25 < ..beta.. < 0.7, are in good agreement with experimental data but the residual nuclei distributions are not. 12 refs., 3 figs.
Date: January 1, 1987
Creator: Alsmiller, F.S.; Alsmiller, R.G. Jr. & Hermann, O.W.
Partner: UNT Libraries Government Documents Department