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Backgrounds to the detection of two-body hadronic B decays

Description: We consider backgrounds to the detection of the two-body hadronic decay modes of neutral B mesons and baryons. The largest background is due to the correlated production of pairs of high-p/sub T/ hadrons in the target, but this can be adequately rejected provided the experimental apparatus has sufficient resolution in mass and decay vertex. Another possible source of background arises from the production and decay of charmed and strange particles. Since these particles can travel considerable d… more
Date: January 8, 1988
Creator: Kaplan, D. M.; Peng, Jen-Chieh; Abrams, G. S. & Stockdale, I. E.
Partner: UNT Libraries Government Documents Department
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Loss of Rare Fish Species from Tropical Floodplain Food Webs Affects Community Structure and Ecosystem Multifunctionality in a Mesocosm Experiment

Description: Article on the loss of rare fish species from tropical floodplain food webs and how this affects community structure and ecosystem multifunctionality in a mesocosm experiment.
Date: January 8, 2014
Creator: Pendleton, Richard M.; Hoeinghaus, David; Gomes, Luiz C. & Agostinho, Angela A.
Partner: UNT College of Arts and Sciences
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Limits on the Superconducting Order Parameter in NdFeAsO_{1-x}F_y from Scanning SQUID Microscopy

Description: Identifying the symmetry of the superconducting order parameter in the recently-discovered ferrooxypnictide family of superconductors, RFeAsO{sub 1-x}F{sub y}, where R is a rare earth, is a high priority. Many of the proposed order parameters have internal {pi} phase shifts, like the d-wave order found in the cuprates, which would result in direction-dependent phase shifts in tunneling. In dense polycrystalline samples, these phase shifts in turn would result in spontaneous orbital currents and… more
Date: January 8, 2009
Creator: Hicks, Clifford W.; Lippman, Thomas M.; Huber, Martin E.; Ren, Zhi-An; Yang, Jie; Zhao, Zhong-Xian et al.
Partner: UNT Libraries Government Documents Department
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A Measurement of the Branching Fractions ofexclusive Bbar to D(*)(pi)lnu Decays in Events with a Fully Reconstructed BMeson

Description: The authors report a measurement of the branching fractions for {bar B} {yields} D{sup (*)}{pi}{ell}{sup -}{bar {nu}}{sub {ell}} decays based on 341.1 fb{sup -1} of data collected at the {Upsilon}(4S) resonance with the BABAR detector at the PEP-II e{sup +}e{sup -} storage rings. Events are tagged by fully reconstructing one of the B mesons in a hadronic decay mode. The obtain {Beta}(B{sup -} {yields} D{sup 0}{ell}{sup -}{bar {nu}}{sub {ell}}) = (2.33 {+-} 0.09{sub stat.} {+-} 0.09{sub syst.})%… more
Date: January 8, 2008
Creator: Aubert, B.
Partner: UNT Libraries Government Documents Department
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Scanning SQUID microscopy on polycrystalline SmFeAsO_{0.85} and NdFeAsO_{0.94}F_{0.06}

Description: The order parameter of the recently-discovered ferric arsenide family of superconductors remains uncertain. Some early experiments on polycrystalline samples suggested line nodes in the order parameter, however later experiments on single crystals have strongly supported fully-gapped superconductivity. An absence of nodes does not rule out unconventional order: {pi} phase shifts between the separate Fermi sheets and time-reversal symmetry-breaking components in the order parameter remain possib… more
Date: January 8, 2009
Creator: Hicks, Clifford W.; Lippman, Thomas M.; Moler, Kathryn A.; Huber, Martin E.; Ren, Zhi-An & Zhao, Zhong-Xian
Partner: UNT Libraries Government Documents Department
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CP Violation at BaBar

Description: Several new and updated BABAR measurements of sin 2{beta} are presented, together with the latest constraints on the Unitarity Triangle angles {alpha} and {gamma}. The higher statistics now available allow more sophisticated analysis techniques, such as time-dependent Dalitz plot fitting. Combined world-average results place tight constraints on the Unitarity Triangle. There is good agreement among the measurements and with the unitarity of the CKM matrix. This represents an impressive verifica… more
Date: January 8, 2008
Creator: Hawkes, Chris & U., /Birmingham
Partner: UNT Libraries Government Documents Department
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Water injection as a means for reducing non-condensible andcorrosive gases in steam produced from vapor-dominated reservoirs

Description: Large-scale water injection at The Geysers, California, hasgenerated substantial benefits in terms of sustaining reservoir pressuresand production rates, as well as improving steam composition by reducingthe content of non-condensible gases (NCGs). Two effects have beenrecognized and discussed in the literature as contributing to improvedsteam composition, (1) boiling of injectate provides a source of "clean"steam to production wells, and (2) pressurization effects induced byboiling of injected… more
Date: January 8, 2007
Creator: Pruess, Karsten; Spycher, Nicolas & Kneafsey, Timothy J.
Partner: UNT Libraries Government Documents Department
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Slow Waves in Fractures Filled with Viscous Fluid

Description: Stoneley guided waves in a fluid-filled fracture generally have larger amplitudes than other waves, and therefore, their properties need to be incorporated in more realistic models. In this study, a fracture is modeled as an infinite layer of viscous fluid bounded by two elastic half-spaces with identical parameters. For small fracture thickness, I obtain a simple dispersion equation for wave-propagation velocity. This velocity is much smaller than the velocity of a fluid wave in a Biot-type so… more
Date: January 8, 2008
Creator: Korneev, Valeri
Partner: UNT Libraries Government Documents Department
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Results from the B Factories

Description: These proceedings are based on lectures given at the Helmholtz International Summer School Heavy Quark Physics at the Bogoliubov Laboratory of Theoretical Physics, Dubna, Russia, during August 2008. I review the current status of CP violation in B meson decays from the B factories. These results can be used, along with measurements of the sides of the Unitarity Triangle, to test the CKM mechanism. In addition I discuss experimental studies of B decays to final states with 'spin-one' particles.
Date: January 8, 2009
Creator: Bevan, A. & /Queen Mary, U. of London
Partner: UNT Libraries Government Documents Department
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Composite Analysis of Llw Disposal Facilities at the U. S. Department of Energy's Savannah River Site

Description: Composite Analyses (CA's) are required per DOE Order 435.1 [1], in order to provide a reasonable expectation that DOE low-level waste (LLW) disposal, high-level waste tank closure, and transuranic (TRU) waste disposal in combination with Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA), Resource Conservation and Recovery Act (RCRA), and deactivation and decommissioning (D&D) actions, will not result in the need for future remedial actions in order to ensure rad… more
Date: January 8, 2009
Creator: Hiergesell, R. A.; Phifer, M. A. & Smith, F. G.
Partner: UNT Libraries Government Documents Department
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Measurement of D^0-\overline{D^0} Mixing using the Ratio of Lifetimes for the Decays D^0 \to K^-\pi^+, K^-K^+, and \pi^-\pi^+

Description: The authors present a measurement of D{sup 0}-{bar D}{sup 0} mixing parameters using the ratios of lifetimes extracted from a sample of D{sup 0} mesons produced through the process D*{sup +} {yields} D{sup 0}{pi}{sup +}, that decay to K{sup -}{pi}{sup +}, I{sup -}K{sup +}, or {pi}{sup -}{pi}{sup +}. the Cabibbo-suppressed modes K{sup -}K{sup +} and {pi}{sup -}{pi}{sup +} are compared to the Cabibbo-favored mode K{sup -}{pi}{sup +} to obtain a measurement of ycp, which in the limit of CP conserv… more
Date: January 8, 2008
Creator: Aubert, B.
Partner: UNT Libraries Government Documents Department
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The Genome of Methylobacillus Flagellatus, the Molecular Basis for Obligate Methylotrophy, and the Polyphyletic Origin of Methylotrophy

Description: Along with methane, methanol and methylated amines representimportant biogenic atmospheric constituents, thus not only methanotrophs,but also non-methanotrophic methylotrophs play a significant role inglobal carbon cycling. The complete genome of a model obligate methanoland methylamine utilizer, Methylobacillus flagellatus (strain KT) wassequenced. The genome is represented by a single circular chromosome ofapproximately 3 Mb pairs, potentially encoding a total of 2,766 proteins.Based on genom… more
Date: January 8, 2007
Creator: Chistoserdova, Ludmila; Lapidus, Alla; Han, Cliff; Goodwin, Lynne; Saunders, Liz; Brettin, Tom et al.
Partner: UNT Libraries Government Documents Department
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Characterization of selective binding of alkali cations with carboxylate by x-ray absorption spectroscopy of liquid microjets

Description: We describe an approach for characterizing selective binding between oppositely charged ionic functional groups under biologically relevant conditions. Relative shifts in K-shell x-ray absorption spectra of aqueous cations and carboxylate anions indicate the corresponding binding strengths via perturbations of carbonyl antibonding orbitals. XAS spectra measured for aqueous formate and acetate solutions containing lithium, sodium, and potassium cations reveal monotonically stronger binding of th… more
Date: January 8, 2008
Creator: Saykally, Richard J; Uejio, Janel S.; Schwartz, Craig P.; Duffin, Andrew M.; Drisdell, Walter S.; Cohen, Ronald C. et al.
Partner: UNT Libraries Government Documents Department
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Transverse Effects Due to Random Displacement of Resistive Wall Segments and Focusing Elements

Description: In this paper, we study the single bunch transverse beam dynamics in the presence of random displacements of resistive wall segments and focusing elements. Analytical formulas are obtained for long-range resistive wall wake, together with numerical results for short-range resistive wall wake. The results are applied to the LCLS project and some other proposed accelerators.
Date: January 8, 2008
Creator: Delayen, J.R.; U., /Jefferson Lab /Old Dominion & Wu, J.
Partner: UNT Libraries Government Documents Department
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Supersymmetric Model Builing (and Sweet Spot Supersymmetry)

Description: It has been more than twenty years since theorists started discussing supersymmetric model building/phenomenology. We review mechanisms of supersymmetry breaking/mediation and problems in each scenario. We propose a simple model to address those problems and discuss its phenomenology.
Date: January 8, 2008
Creator: Ibe, Masahiro; /SLAC /Stanford U., Phys. Dept.; Kitano, Ryuichiro & Alamos, /Los
Partner: UNT Libraries Government Documents Department
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Transverse Effect Due to Short Range Resistive Wall Wakefield

Description: For accelerator designs with ultra short electron beams, beam dynamics study has to invoke the short-range wakefields. In this paper, we first obtain the short-range dipole mode resistive wall wakefield. Analytical approach is then developed to study the single bunch transverse beam dynamics due to this short-range resistive wall wake. The results are applied to the LCLS undulator.
Date: January 8, 2008
Creator: Delayen, J. R.; Chao, Alexander Wu & Wu, J.
Partner: UNT Libraries Government Documents Department
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Self Consistent Monte Carlo Method to Study CSR Effects in Bunch Compressors

Description: In this paper we report on the results of a self-consistent calculation of CSR effects on a particle bunch moving through the benchmark Zeuthen bunch compressors. The theoretical framework is based on a 4D Vlasov-Maxwell approach including shielding from the vacuum chamber. We calculate the fields in the lab frame, where time is the independent variable, and evolve the phase space density/points in the beam frame, where arc length, s, along a reference orbit, is the independent variable. Some d… more
Date: January 8, 2008
Creator: Warnock, R. L.; Bassi, G.; Ellison, J. A. & Heinemann, K. A.
Partner: UNT Libraries Government Documents Department
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Wetting of metals and glasses on Mo

Description: The wetting of low melting point metals and Si-Ca-Al-Ti-O glasses on molybdenum has been investigated. The selected metals (Au, Cu, Ag) form a simple eutectic with Mo. Metal spreading occurs under nonreactive conditions without interdiffusion or ridge formation. The metals exhibit low (non-zero) contact angles on Mo but this requires temperatures higher than 1100 C in reducing atmospheres in order to eliminate a layer of adsorbed impurities on the molybdenum surface. By controlling the oxygen a… more
Date: January 8, 2008
Creator: Saiz, Eduardo; Tomsia, Antoni P.; Saiz, Eduardo; Lopez-Esteban, Sonia; Benhassine, Mehdi; de Coninck, Joel et al.
Partner: UNT Libraries Government Documents Department
open access

A low-energy linear oxygen plasma source

Description: A new version of a Constricted Plasma Source is described,characterized by all metal-ceramic construction, a linear slit exit of180 mm length, and cw-operation (typically 50 kHz) at an average power of1.5 kW. The plasma source is here operated with oxygen gas, producingstreaming plasma that contains mainly positive molecular and atomic ions,and to a much lesser degree, negative ions. The maximum total ion currentobtained was about 0.5 A. The fraction of atomic ions reached more than10 percent o… more
Date: January 8, 2007
Creator: Anders, Andre & Yushkov, Georgy Yu.
Partner: UNT Libraries Government Documents Department
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Coherent Synchrotron Radiation and Space Charge for a 1-D Bunch on an Arbitrary Planar Orbit

Description: Realistic modeling of coherent synchrotron radiation (CSR) and the space charge force in single-pass systems and rings usually requires at least a two-dimensional (2-D) description of the charge/current density of the bunch. Since that leads to costly computations, one often resorts to a 1-D model of the bunch for first explorations. This paper provides several improvements to previous 1-D theories, eliminating unnecessary approximations and physical restrictions.
Date: January 8, 2008
Creator: Warnock, R. L.
Partner: UNT Libraries Government Documents Department
open access

Fourth-Order Method for Numerical Integration of Age- and Size-Structured Population Models

Description: In many applications of age- and size-structured population models, there is an interest in obtaining good approximations of total population numbers rather than of their densities. Therefore, it is reasonable in such cases to solve numerically not the PDE model equations themselves, but rather their integral equivalents. For this purpose quadrature formulae are used in place of the integrals. Because quadratures can be designed with any order of accuracy, one can obtain numerical approximation… more
Date: January 8, 2008
Creator: Iannelli, M; Kostova, T & Milner, F A
Partner: UNT Libraries Government Documents Department
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THE THICKNESS DEPENDENCE OF OXYGEN PERMEABILITY IN SOL-GEL DERIVED CGO-COFE2O4 THIN FILMS ON POROUS CERAMIC SUBSTRATES: A SPUTTERED BLOCKING LAYER FOR THICKNESS CONTROL

Description: Mixed conductive oxides are a topic of interest for applications in oxygen separation membranes as well as use in producing hydrogen fuel through the partial oxidation of methane. The oxygen flux through the membrane is governed both by the oxygen ionic conductivity as well as the material's electronic conductivity; composite membranes like Ce{sub 0.8}Gd{sub 0.2}O{sub 2-{delta}} (CGO)-CoFe{sub 2}O{sub 4} (CFO) use gadolinium doped ceria oxides as the ionic conducting material combined with coba… more
Date: January 8, 2009
Creator: Brinkman, K
Partner: UNT Libraries Government Documents Department
open access

Editing graphs for maximum effect

Description: The paper contains over eighty rules for editing graphs, arranged under nine major headings in a logical sequence for editing all the graphs in a manuscript. It is excerpted from a monograph used at the Lawrence Livermore National Laboratory to train beginning technical editors in editing graphs; a corresponding Hypercard stack is also used in this training. 6 refs., 4 figs.
Date: January 8, 1991
Creator: Murphy, P. W. & Rhiner, R. W.
Partner: UNT Libraries Government Documents Department
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Supernova explosions and hydrodynamical instabilities: From core bounce to 90 days

Description: Since the advent of SN 1987A considerable progress has been made in our understanding of supernova explosions. It is now realized that they are intrinsically multidimensional in nature due to the various hydrodynamical instabilities which take place at almost all stages of the explosion. These instabilities not only modify the observables from the supernova, but are also thought to be at the heart of the supernova mechanism itself, in a way which guarantees robust and self-regulated explosions.… more
Date: January 8, 1993
Creator: Benz, W.; Colgate, S. A. & Herant, M.
Partner: UNT Libraries Government Documents Department
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