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Search for narrow states produced in the reaction. pi. /sup -/p. -->. n +. gamma. 's at 13 GeV/c

Description: A double arm lead-glass lead-scintillator calorimeter system was used to search for narrow states, such as the eta/sub c/, produced in the exclusive reactions ..pi../sup -/p ..-->.. ..gamma gamma..n, ..pi../sup -/p ..-->.. ..pi../sup 0/..gamma..n, and ..pi../sup -/p ..-->.. ..pi../sup 0/..pi../sup 0/n at 13 GeV/c. A 90% c.l. upper limit sigma.BR < 260 pb was found for ..gamma gamma.. states with masses from 2.6 to 3.1 GeV/c/sup 2/. Corresponding limits on narrow ..pi../sup 0/..gamma… more
Date: July 7, 1980
Creator: Chiang, I. H.; Johnson, R. A. & Kwan, B.
Partner: UNT Libraries Government Documents Department
open access

MODELING OF NI-CR-MO BASED ALLOYS: PART II - KINETICS

Description: The CALPHAD approach is applied to kinetic studies of phase transformations and aging of prototypes of Ni-Cr-Mo-based alloys selected for waste disposal canisters in the Yucca Mountain Project (YMP). Based on a previous study on alloy stability for several candidate alloys, the thermodynamic driving forces together with a newly developed mobility database have been used to analyze diffusion-controlled transformations in these Ni-based alloys. Results on precipitation of the Ni{sub 2}Cr-ordered … more
Date: July 7, 2006
Creator: Turchi, P A; Kaufman, L & Liu, Z
Partner: UNT Libraries Government Documents Department
open access

High Pressure Materials Research using Advanced Third-Generation Synchrotron X-ray

Description: The recent discoveries of nonmolecular phases of simple molecular solids [1,2] demonstrate the proof-of-the-principles for producing exotic phases by application of high pressure. Modern advances in theoretical and computational methodologies now make possible to explain or even predict novel structures and properties in a relatively wide range of length scales on the basis of thermodynamic stability [3]. Equally important in materials research is the recent developments in advanced x-ray and l… more
Date: July 7, 2006
Creator: Yoo, C. S.; Iota, V.; Park, J.; Lee, G.; Evans, W.; Jenei, Z. et al.
Partner: UNT Libraries Government Documents Department
open access

Wakefield and RF Kicks Due to Coupler Asymmetry in TESLA-Type Accelerating Cavities

Description: In a future linear collider, such as the International Linear Collider (ILC), trains of high current, low emittance bunches will be accelerated in a linac before colliding at the interaction point. Asymmetries in the accelerating cavities of the linac will generate fields that will kick the beam transversely and degrade the beam emittance and thus the collider performance. In the main linac of the ILC, which is filled with TESLA-type superconducting cavities, it is the fundamental (FM) and high… more
Date: July 7, 2008
Creator: Bane, K. L. F.; Adolphsen, C.; Li, Z.; Dohlus, M.; Zagorodnov, I.; Gonin, I. et al.
Partner: UNT Libraries Government Documents Department
open access

Probing QCD with Rare Charmless $B$ Decays

Description: Rare charmless hadronic B decays are a good testing ground for QCD. In this paper we describe a selection of new measurements made by the BABAR and BELLE collaborations.
Date: July 7, 2006
Creator: Gradl, Wolfgang
Partner: UNT Libraries Government Documents Department
open access

The powers of deconfinement

Description: The trace anomaly of gluodynamics encodes the breakdown of classical scale invariance due to interactions around the deconfinement phase transition. While it is expected that at high temperatures perturbation theory becomes applicable we show that current lattice calculations are far from the perturbative regime and are dominated instead by inverse even power corrections in the temperature, while the total perturbative contribution is estimated to be extremely small and compatible with zero wit… more
Date: July 7, 2008
Creator: Megias,E.; Ruiz Arriola, E.; Megias, E. & Salcedo, L.L.
Partner: UNT Libraries Government Documents Department
open access

SABER Optical Design

Description: SABER, the South Arc Beam Experimental Region, is a proposed new beam line facility designed to replace the Final Focus Test Beam at SLAC. In this paper, we outline the optical design features and beam parameters now envisioned for SABER. A magnetic chicane to compress positron bunches for SABER and a bypass line that could transport electrons or positrons from the two-thirds point of the linac to SABER, bypassing the LCLS systems, are also discussed.
Date: July 7, 2006
Creator: Erickson, R.; Bane, K.; Emma, P. & Nosochkov, Y.
Partner: UNT Libraries Government Documents Department
open access

SNAP Satellite Focal Plane Development

Description: The proposed SuperNova/Acceleration Probe (SNAP) mission will have a two-meter class telescope delivering diffraction-limited images to an instrumented 0.7 square degree field in the visible and near-infrared wavelength regime. The requirements for the instrument suite and the present configuration of the focal plane concept are presented. A two year R&D phase, largely supported by the Department of Energy, is just beginning. We describe the development activities that are taking place to a… more
Date: July 7, 2003
Creator: Bebek, C.; Akerlof, C.; Aldering, G.; Amanullah, R.; Astier, P.; Baltay, C. et al.
Partner: UNT Libraries Government Documents Department
open access

Measurements and Analysis of Longitudinal HOM Driven Coupled Bunch Modes in PEP-II Rings

Description: The growth rates of the longitudinal higher-order impedance-driven beam modes have greatly increased since the initial PEP-II design and commissioning. This increase is attributed to the addition of 6 1.2MW RF stations with 8 accelerating cavities in the HER and 2 1.2MW RF stations with 4 accelerating cavities in the LER, which allowed operations at twice the design current and almost four times the luminosity. As a result, the damping requirements for the longitudinal feedback have greatly inc… more
Date: July 7, 2008
Creator: Mastorides, T; Rivetta, C.; Fox, J. D. & Winkle, D. Van
Partner: UNT Libraries Government Documents Department
open access

Modeling and Simulation of the Longitudinal Beam Dynamics - RF Station Interaction in the LHC Rings

Description: A non-linear time-domain simulation has been developed to study the interaction between longitudinal beam dynamics and RF stations in the LHC rings. The motivation for this tool is to determine optimal LLRF configurations, to study system sensitivity on various parameters, and to define the operational and technology limits. It will be also used to study the effect of RF station noise, impedance, and perturbations on the beam life time and longitudinal emittance. It allows the study of alternat… more
Date: July 7, 2008
Creator: Mastorides, T; Rivetta, C.; Fox, J. D.; Winkle, D.Van; Baudrenghien, P. & Tuckmantel, J.
Partner: UNT Libraries Government Documents Department
open access

PRODUCTION OF S = 0, -1 RESONANT STATES IN K<sup>-</sup> p INTERACTIONS AT 2.45 GeV/c

Description: About 70,000 pictures of 2.45-GeV/c K{sup -}-p interactions have been obtained in the present 72-inch hydrogen bubble-chamber experiment. Approximately 24,000 events of all topologies except 1-, 2-, and 3-prong events have been measured, and 50% have been remeasured. They report here on a study of the production of known resonances in the reactions: (1) K{sup -} + p {yields} {Lambda} + {pi}{sup +} + {pi}{sup -}; (2) K{sup -} + p {yields} {Lambda} + {pi}{sup +} + {pi}{sup 0} + {pi}{sup -}. The c… more
Date: July 7, 1964
Creator: Ross, Ronald R.; Friedman, Jerome H.; Siegel, Daniel M.; Flatte,Stanley; Alvarez, Luis W.; Barbaro-Galtieri, Angela et al.
Partner: UNT Libraries Government Documents Department
open access

Design of a combinatorial dna microarray for protein-dnainteraction studies

Description: Background: Discovery of precise specificity oftranscription factors is an important step on the way to understandingthe complex mechanisms of gene regulation in eukaryotes. Recently,doublestranded protein-binding microarrays were developed as apotentially scalable approach to tackle transcription factor binding siteidentification. Results: Here we present an algorithmic approach toexperimental design of a microarray that allows for testing fullspecificity of a transcription factor binding to a… more
Date: July 7, 2006
Creator: Mintseris, Julian & Eisen, Michael B.
Partner: UNT Libraries Government Documents Department
open access

Analysis of Longitudinal Beam Dynamics Behavior and RF System Operative Limits at High Beam Currents in Storage Rings

Description: A dynamics simulation model is used to estimate limits of performance of the Positron-Electron Project (PEP-II). The simulation captures the dynamics and technical limitations of the Low Level Radio Frequency (LLRF) system, the high-power RF components and the low-order mode coupled bunch longitudinal beam dynamics. Simulation results showing the effect of non-linearities on the LLRF loops, and studies of the effectiveness of technical component upgrades are reported, as well as a comparison of… more
Date: July 7, 2008
Creator: Mastorides, T; Rivetta, C.; Fox, J. D.; Winkle, D. Van & Tytelman, D.
Partner: UNT Libraries Government Documents Department
open access

Sunfall: a collaborative visual analytics system for astrophysics

Description: Computational and experimental sciences produce and collect ever-larger and complex datasets, often in large-scale, multi-institution projects. The inability to gain insight into complex scientific phenomena using current software tools is a bottleneck facing virtually all endeavors of science. In this paper, we introduce Sunfall, a collaborative visual analytics system developed for the Nearby Supernova Factory, an international astrophysics experiment and the largest data volume supernova sea… more
Date: July 7, 2008
Creator: Aragon, Cecilia R.; Aragon, Cecilia R.; Bailey, Stephen J.; Poon, Sarah; Runge, Karl & Thomas, Rollin C.
Partner: UNT Libraries Government Documents Department
open access

Performance evaluation of the HEP, ELXSI and CRAY X-MP parallel processors on hydrocode test problems

Description: Parallel programming promises improved processing speeds for hydrocodes, magnetohydrocodes, multiphase flow codes, thermal-hydraulics codes, wavecodes and other continuum dynamics codes. This paper presents the results of some investigations of parallel algorithms on three parallel processors: the CRAY X-MP, ELXSI and the HEP computers. Introduction and Background: We report the results of investigations of parallel algorithms for computational continuum dynamics. These programs (hydrocodes, wa… more
Date: July 7, 1986
Creator: Liebrock, L. M.; McGrath, J. F. & Hicks, D. L.
Partner: UNT Libraries Government Documents Department
open access

[Fort Worth Star-Telegram, July 7-13, 1995]

Description: An article in the Fort Worth Star-Telegram about the upcoming collections and events at the Amon Carter Museum in Fort Worth. It is titled Little Journeys and has information about tours and group visits.
Date: [1995-07-07..1995-07-13]
Creator: Fort Worth Star-Telegram
Partner: UNT Libraries Special Collections
open access

Fission barriers of hot rotating nuclei: Theoretical predictions and experimental tests

Description: Recent theoretical developments in calculating fission barriers of hot rotating nuclei and their experimental tests are reviewed. The discussions are limited to macroscopic fission models (no shell effects), since experimental tests come primarily from heavy-ion induced reactions involving large angular momenta and internal excitation energies. The physics of the rotating finite range models with temperature is emphasized and the predictions of our model are compared with those of other macrosc… more
Date: July 7, 1987
Creator: Mustafa, M.G.
Partner: UNT Libraries Government Documents Department
open access

Cleanroom Energy Efficiency: Metrics and Benchmarks

Description: Cleanrooms are among the most energy-intensive types of facilities. This is primarily due to the cleanliness requirements that result in high airflow rates and system static pressures, as well as process requirements that result in high cooling loads. Various studies have shown that there is a wide range of cleanroom energy efficiencies and that facility managers may not be aware of how energy efficient their cleanroom facility can be relative to other cleanroom facilities with the same cleanli… more
Date: July 7, 2010
Creator: Initiative, International SEMATECH Manufacturing; Mathew, Paul A.; Tschudi, William; Sartor, Dale & Beasley, James
Partner: UNT Libraries Government Documents Department
open access

Theoretical and observational review of results on nova explosions occurring on ONeMg white dwarfs

Description: The nova outburst is the second most violent explosion that occurs in a galaxy. This review presents the recent observational and theoretical studies that have demonstrated that there exist two classes of nova outburst. One type of nova occurs on a CO white dwarf and the other type of nova occurs on an ONeMg white dwarf. The second class of outbursts are much more violent and occur much more frequently then the first class of outbursts. Hydrodynamic simulations of both kinds of outbursts are in… more
Date: July 7, 1986
Creator: Starrfield, S.
Partner: UNT Libraries Government Documents Department
open access

Group velocity and pulse lengthening of mismatched laser pulses in plasma channels

Description: Analytic solutions are presented to the non-paraxial wave equation describing an ultra-short, low-power, laser pulse propagating in aplasma channel. Expressions for the laser pulse centroid motion and laser group velocity are derived, valid for matched and mismatchedpropagation in a parabolic plasma channel, as well as in vacuum, for an arbitrary Laguerre-Gaussian laser mode. The group velocity of amismatched laser pulse, for which the laser spot size is strongly oscillating, is found to be ind… more
Date: July 7, 2011
Creator: Schroeder, Carl; Benedetti, Carlo; Esarey, Eric; van Tilborg, Jeroen & Leemans, Wim
Partner: UNT Libraries Government Documents Department
open access

5000 groove/mm multilayer-coated blazed grating with 33percent efficiency in the 3rd order in the EUV wavelength range

Description: We report on recent progress in developing diffraction gratings which can potentially provide extremely high spectral resolution of 105-106 in the EUV and soft x-ray photon energy ranges. Such a grating was fabricated by deposition of a multilayer on a substrate which consists ofa 6-degree blazed grating with a high groove density. The fabrication of the substrate gratings was based on scanning interference lithography and anisotropic wet etch of silicon single crystals. The optimized fabricati… more
Date: July 7, 2009
Creator: Lawrence Berkeley National Laboratory. Advanced Light Source.
Partner: UNT Libraries Government Documents Department
open access

Inclusive pi^0, eta, and direct photon production at high transverse momentum in p+p and d+Au collisions at sqrt(s_NN) = 200 GeV

Description: We report a measurement of high-p{sub T} inclusive {pi}{sup 0}, {eta}, and direct photon production in p + p and d + Au collisions at {radical}s{sub NN} = 200 GeV at midrapidity (0 &lt; {eta} &lt; 1). Photons from the decay {pi}{sup 0} {yields} {gamma}{gamma} were detected in the Barrel Electromagnetic Calorimeter of the STAR experiment at the Relativistic Heavy Ion Collider. The {eta} {yields} {gamma}{gamma} decay was also observed and constituted the first {eta} measurement by STAR. The first… more
Date: July 7, 2010
Creator: STAR Collaboration
Partner: UNT Libraries Government Documents Department
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