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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

Mechanical design of a large bore quadrupole triplet magnet

Description: The mechanical design and construction of a 1 meter bore, low gradient quadrupole triplet is described. The magnet will be used for focussing a proton beam in accelerator studies of neutral particle at the Los Alamos National Laboratory. A significant feature of this magnet design is the precision location of the coil conductors within the steel yoke tube. Each of the quadrupole coils have been fabricated from water cooled aluminum conductor, wound in a cosine 2-theta geometry. The conductor bundles have been wound to a positional accuracy within +-0.050 cm which was required to reduce the harmonic content to less than 0.04% of the quadrupole field. Important aspects of the design, construction and assembly are described.
Date: March 1, 1987
Creator: Abbott, S.; Caylor, R.; Fong, E. & Tanabe, J.
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

Elastic scattering of muon neutrinos at BNL

Description: In this paper measurement of the purely leptonic reactions: nu/sub ..mu../e ..-->.. nu/sub ..mu../e and anti nu/sub ..mu../e ..-->.. anti nu/sub ..mu../e, and the semileptonic reactions: nu/sub ..mu../p ..-->.. nu/sub ..mu../p and anti nu/sub ..mu../p ..-->.. anti nu/sub ..mu../p are presented and discussed in terms of the standard model. The data also places limites of interest on the magnitudes of a possible neutrino charge radius and a neutrino magnetic moment.
Date: February 1, 1987
Creator: Abe, K.; Ahrens, L.A.; Amako, K.; Aronson, S.H.; Beier, E.W.; Callas, J.L. 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

Experience in using workstations as hosts in an accelerator control environment

Description: A new control system has been used for light ion acceleration at the Alternating Gradient Synchrotron (AGS). The control system uses Apollo workstations in the dual role of console hardware computer and controls system host. It has been found that having a powerful dedicated CPU with a demand paging virtual memory OS featuring strong interprocess communication, mapped memory shared files, shared code, and multi-window capabilities, allows us to provide an efficient operation environment in which users may view and manage several control processes simultaneously. The same features which make workstations good console computers also provide an outstanding platform for code development. The software for the system, consisting of about 30K lines of ''C'' code, was developed on schedule, ready for light ion commissioning. System development is continuing with work being done on applications programs.
Date: March 1, 1987
Creator: Abola, A.; Casella, R.; Clifford, T.; Hoff, L.; Katz, R.; Kennell, S. et al.
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

Instabilities of higher dimensional compactifications

Description: Various schemes for cosmological compactification of higher dimensional theories are considered. Possible instabilities which drive the ground state with static internal space to de Sitter-like expansion of all dimensions are discussed. These instabilities are due to semiclassical barrier penetration and classical thermal fluctuations. For the case of the ten dimensional Chapline-Manton action, it is possible to avoid such difficulties by balancing one-loop Casimir corrections against monopole contributions from the field strength H/sub MNP/ and fermionic condensates. 10 refs.
Date: February 1, 1987
Creator: Accetta, F.S.
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

Comment on "Thermochemical Investigations of Associated Solutions: Calculation of Solute-Solvent Equilibrium Constants from Solubility Measurements"

Description: This article provides comments on "Thermochemical Investigations of Associated Solutions: Calculation of Solute-Solvent Equilibrium Constants from Solubility Measurements," published in the Journal of Pharmaceutical Sciences in 1983.
Date: July 1, 1987
Creator: Acree, William E. (William Eugene)
Partner: UNT College of Arts and Sciences

Thermochemical Investigations of Associated Solutions: 5. Calculation of Solute-Solvent Equilibrium Constants from Solubility in Mixtures Containing Two Complexing Solvents

Description: Article on thermochemical investigations of associated solutions and the calculation of solute-solvent equilibrium constants from solubility in mixtures containing two complexing solvents.
Date: July 1, 1987
Creator: Acree, William E. (William Eugene) & McCargar, James W.
Partner: UNT College of Arts and Sciences

Nuclear breakup and particle densities in 200 A GeV - /sup 16/O interactions with emulsion nuclei

Description: Experiment EMU-01 makes use of emulsion chambers and conventional stacks to study the interactions in matter of 200 A GeV /sup 16/O nuclei accelerated at the CERN SPS. Projectile fragmentation is compatible with such interactions of /sup 16/O nuclei at 2 A GeV, indications of limiting fragmentation. Particle production is examined via high precision pseudo-rapidity distributions. Energy densities up to about 3 GeVfm/sup 3/ are observed in central /sup 16/O + Ag(Br) interactions. Pseudo-rapidity density distributions and fluctuations are well reproduced by the MC model Pritiof, although the existence of new and unknown sources of density fluctuations are not excluded by the data. 7 refs., 7 figs.
Date: September 1, 1987
Creator: Adamovich, M.I.; Alexandrov, Y.A.; Asimov, S.A.; Badyal, S.K.; Basova, E. & Bhalla, K.B.
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

The Mark III vertex chamber

Description: The design and construction of the new Mark III vertex chamber is described. Initial tests with cosmic rays prove the ability of track reconstruction and yield triplet resolutions below 50 ..mu..m at 3 atm using argon/ethane (50:50). Also performed are studies using a prototype of a pressurized wire vertex chamber with 8 mm diameter straw geometry. Spatial resolution of 35mm was obtained using dimethyl ether (DME) at 1 atm and 30 ..mu..m using argon/ethane (50/50 mixture) at 4 atm. Preliminary studies indicate the DME to adversely affect such materials as aluminized Mylar and Delrin.
Date: July 1, 1987
Creator: Adler, J.; Bolton, T.; Bunnell, K.; Cassell, R.; Cheu, E.; Freese, T. et al.
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

Status of the silicon strip vertex detector for the Mark II experiment at the SLC

Description: We are constructing a silicon strip vertex detector to be used in the Mark II detector in the study of Z/sup 0/ decays at the SLAC Linear Collider. The status of the project, including the performance of the individual silicon detector modules, is presented. 6 refs., 8 figs., 2 tabs.
Date: October 1, 1987
Creator: Adolphsen, C.; Gratta, G.; Litke, A.; Schwarz, A.; Turala, M.; Breakstone, A. et al.
Partner: UNT Libraries Government Documents Department

Nuclide migration from areal sources into a fracture

Description: This document shows analytic solutions to the problem of hydrogeologic transport of radionuclides released from finite areal sources into a planar fracture. It illustrates the solutions through numerical and graphical displays of the spatial and temporal distribution of the radionuclides as a result of advection in the fracture, transverse dispersion and surface sorption, as well as diffusion into and sorption in the rock matrix. The numerical illustrations indicate that sufficient distances away from the sources equivalent single sources give acceptable approximations. 2 refs., 3 figs.
Date: April 1, 1987
Creator: Ahn, J.; Chambre, P.L.; Pigford, T.H. & Lee, W.W.L.
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

Cosmology for high energy physicists

Description: The standard big bang model of cosmology is presented. Although not perfect, its many successes make it a good starting point for most discussions of cosmology. Places are indicated where well understood laboratory physics is incorporated into the big bang, leading to successful predictions. Much less established aspects of high energy physics and some of the new ideas they have introduced into the field of cosmology are discussed, such as string theory, inflation and monopoles. 49 refs., 5 figs.
Date: November 1, 1987
Creator: Albrecht, A.
Partner: UNT Libraries Government Documents Department

Advances in inherently conducting polymers

Description: The discovery of polyacetylene as the prototype material led to extensive research on its synythesis and characterization. The techniques that emerged as the most important and promising ones are those that dealt with molecular orientation and that resulted in conductivities almost as high as that of copper. The study of dozens of other materials followed. Interest in conducting polymers stems from their nonclassical optical and electronic properties as well as their potential technological applications. However, some of the factors currently limiting their use are the lack of long-term stability and the need to develop conventional low-cost techniques for easy processing. Therefore, research was extended toward solving these problems, and progress has been recently made in that direction. The synthesis of new materials such as stable and easily processable alkylthiophenes, water-soluble polymers, and multicomponent systems, including copolymers and composites, constitutes an important step forward in the area of synthetic metals. However, a full understanding of materials chemistry and properties requires more work in the years to come. Although, few small-scale applications have proven to be successful, long-term stability and applicability tests are needed before their commercial use becomes reality.
Date: September 1, 1987
Creator: Aldissi, M.
Partner: UNT Libraries Government Documents Department