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A Next-to-Leading-Order QCD Analysis of Neutrino-Iron Structure Functions at the Tevatron

Description: Nucleon structure functions measured in neutrino-iron and antineutrino-iron charged-current interactions are presented. The data were taken in two high-energy high-statistics runs by the LAB-E detector at the Fermilab Tevatron. Structure functions are extracted from a sample of 950,000 neutrino and 170,000 antineutrino events with neutrino energies from 30 to 360 GeV. The structure functions F{sub 2} and xF{sub 3} are compared with the predictions of perturbative Quantum Chromodynamics (PQCD). … more
Date: June 1, 1997
Creator: Seligman, W. G.
Partner: UNT Libraries Government Documents Department
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Duals for SU(N) SUSY Gauge Theories with an Antisymmetric Tensor: Five Easy Flavors

Description: I consider N = 1 supersymmetric SU(N{sub c}) gauge theories with matter fields consisting of one antisymmetric representation, five flavors, and enough antifundamental representations to cancel the gauge anomaly. Previous analyses are extended to the case of even N{sub c} with no superpotential. Using holomorphy I show that the theory has an interacting infrared fixed point for sufficiently large N{sub c}. These theories are interesting due to the fact that in going from five to four flavors th… more
Date: December 16, 1997
Creator: Terning, John
Partner: UNT Libraries Government Documents Department
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Recent Progress in Weakly-Coupled Heterotic String Phenomenology

Description: Some recent developments in the weakly-coupled heterotic string phenomenology are reviewed. We discuss several important issues such as dilaton/moduli stabilization, supersymmetry breaking (by hidden-sector gaugino condensation), gauge coupling unification (or the Newton's constant), the QCD axion, as well as cosmological problems involving the dilaton/moduli and the axion.
Date: July 28, 1997
Creator: Wu, Yi-Yen
Partner: UNT Libraries Government Documents Department
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Strong Decays of Hybrid Mesons from the Heavy Quark Expansion of QCD

Description: We calculate the strong decays of hybrid mesons to conventional mesons for all the lowest lying J{sup PC} hybrids of flavour u{bar u}, d{bar d}, s{bar s}, c{bar c} and b{bar b}. A decay operator developed from the heavy quark expansion of quantum chromodynamics is employed. We show that the selection rule that hybrid mesons do not decay to identical S-wave mesons, found in other models, is preserved. We predict decays of charmonium hybrids, discuss decays of J{sup PC} = 1{sup -+} exotic isovect… more
Date: August 1, 1997
Creator: Page, Philip R.
Partner: UNT Libraries Government Documents Department
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Deuteron photodisintegration : new results from TJNAF.

Description: The first measurements of the differential cross section from d({gamma},p)n up to 4.0 GeV were performed at the Thomas Jefferson National Accelerator Facility (TJNAF, formerly CEBAF). Bremsstrahlung photons from electron beam impinging on a copper radiator and a liquid deuterium target were employed for this experiment. The experiment was performed in Hall C where the photoprotons at forward angles in the center-of-mass were detected in the High Momentum Spectrometer (HMS) and photoprotons at b… more
Date: November 18, 1997
Creator: Abbott, D. J.; Ahmidouch, A.; Armstrong, C. S.; Arrington, J.; Cummings, W. J.; Geesaman, D. F. et al.
Partner: UNT Libraries Government Documents Department
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Problems at the interface between heavy flavor physics, QCD and hadron spectroscopy.

Description: The following subjects are discussed in this report: (1) Pentaquark--why it is important and how new technologies (vertex detectors) suggest drastically different approaches form the search used by Ashery et al.; (2) problems in B decays with implications for heavy quark decays to excited light quark states like the Al; (3) problems in B and D decays to final states including {eta} and {eta}{prime} indicating that standard quark mixing might not hold; (4) possible contributions of hybrid quarko… more
Date: December 12, 1997
Creator: Lipkin, H. J.
Partner: UNT Libraries Government Documents Department
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Strongly-interacting color-singlet exchange in {anti p}-p collisions at {radical}s = 1800 GeV

Description: Results are presented from an analysis of the particle multiplicity between high transverse energy jets in {anti p}-p collisions at {radical}s = 1,800 GeV. The data were collected using the D0 Detector at Fermi National Accelerator Laboratory. The authors observe an excess of events at low multiplicity which is consistent with strongly interacting color-singlet exchange. The fraction of events due to color-singlet exchange is measured as a function of the transverse energy and rapidity separati… more
Date: December 1, 1997
Creator: Thomas, T.L.T.
Partner: UNT Libraries Government Documents Department
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QCD subgroup on diffractive and forward physics

Description: Over the last few years, there has been a resurgence of interest in small-x or diffractive physics. This has been due to the realization that perturbative QCD techniques may be applicable to what was previously thought of as a non-perturbative problem and to the opening up of new energy regimes at HERA and the Tevatron collider. The goal is to understand the pomeron, and hence the behavior of total cross sections, elastic scattering and diffractive excitation, in terms of the underlying theory,… more
Date: September 1, 1997
Creator: Albrow, M.G.; Baker, W. & Bhatti, A.
Partner: UNT Libraries Government Documents Department
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Exclusive photon-photon processes

Description: Exclusive gamma gamma right arrow hadron pairs are among the most fundamental processes in QCD, providing a detailed examination of Compton scattering in the crossed channel. In the high momentum transfer domain (s, t, large, Theta cm for t/s fixed), these processes can be computed from first principles in QCD, yielding important information on the nature of the QCD coupling data and the form of hadron distribution amplitudes. Similarly, the transition form factors gamma star gamma, gamma star … more
Date: July 1, 1997
Creator: Brodsky, Stanley J.
Partner: UNT Libraries Government Documents Department
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Excess cross-sections at the electroweak scale in the sextet quark {open_quotes}standard model{close_quotes}

Description: If dynamical electroweak symmetry breaking is due to a flavor doublet of color sextet quarks, enhanced electroweak scale QCD instanton interactions may produce a large top mass, raise the {eta}{sub 6} axion mass, and also explain the excesses in the DIS cross-section at HERA and jet cross-sections at the Tevatron.
Date: June 30, 1997
Creator: White, A.R.
Partner: UNT Libraries Government Documents Department
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The Pomeron beyond BFKL

Description: Conformally invariant reggeon interactions derived from t-channel unitarity are discussed and progress towards understanding the {open_quotes}physical Pomeron{close_quotes}, via massless quark reggeon interactions, is briefly out-lined.
Date: May 12, 1997
Creator: White, A. R.
Partner: UNT Libraries Government Documents Department
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Summary of the Very Large Hadron Collider Physics and Detector Workshop

Description: One of the options for an accelerator beyond the LHC is a hadron collider with higher energy. Work is going on to explore accelerator technologies that would make such a machine feasible. This workshop concentrated on the physics and detector issues associated with a hadron collider with an energy in the center of mass of the order of 100 to 200 TeV.
Date: October 1, 1997
Creator: Anderson, G.; Berger, M.; Brandt, A. & Eno, S.
Partner: UNT Libraries Government Documents Department
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Theoretical nuclear physics. Final report

Description: As the three-year period FY93-FY96 ended, there were six senior investigators on the grant full-time: Bulgac, Henley, Miller, Savage, van Kolck and Wilets. This represents an increase of two members from the previous three-year period, achieved with only a two percent increase over the budget for FY90-FY93. In addition, the permanent staff of the Institute for Nuclear Theory (George Bertsch, Wick Haxton, and David Kaplan) continued to be intimately associated with our physics research efforts. … more
Date: May 1, 1997
Partner: UNT Libraries Government Documents Department
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A continuum order parameter for deconfinement

Description: Dyson-Schwinger equations are presented as a non-perturbative tool for the study and modeling of QCD at finite-{ital T}. An order parameter for deconfinement, applicable for both light and heavy quarks, is introduced. In a simple Dyson-Schwinger equation model of two-flavor QCD, coincident, 2nd-order chiral symmetry restoration and deconfinement transitions occur at {ital T} {approx} 150 MeV, with the same critical exponent, {Beta} {approx} 0.33.
Date: March 1, 1997
Creator: Roberts, C.D.
Partner: UNT Libraries Government Documents Department
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Physics at the Z pole with SLD

Description: The authors review recent results from a wide physics program in polarized e{sup +}e{sup {minus}} interactions at the SLC performed by the SLD experiment. Unique and precise measurements of the electroweak parameters A{sub e}, A{sub b}, A{sub c}, and R{sub b} provide valuable constraints on the Standard Model. The excellent 3-D vertexing capabilities of SLD are further exploited to extract precise B{sup +} and B{sub d}{sup 0} lifetimes, as well as measurements of the time evolution of B{sub d}{… more
Date: June 1, 1997
Creator: Willocq, S.
Partner: UNT Libraries Government Documents Department
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Precise tests of QCD in e{sup +}e{sup {minus}} annihilation

Description: A pedagogical review is given of precise tests of QCD in electron-positron annihilation. Emphasis is placed on measurements that have served to establish QCD as the correct theory of strong interactions, as well as measurements of the coupling parameter {alpha}{sub s}. An outlook is given for future important tests at a high-energy e{sup +}e{sup {minus}} collider.
Date: March 1, 1997
Creator: Burrows, P.N.
Partner: UNT Libraries Government Documents Department
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Rare kaon decays

Description: The phenomenology of rare kaon decays is reviewed, with emphasis on tests of standard model flavordynamics.
Date: January 1, 1997
Creator: Buchalla, G.
Partner: UNT Libraries Government Documents Department
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Spin-dependent Drell-Yan and double prompt photon production to NLO QCD

Description: We present the complete O({alpha}{sub s}{sup 2}) radiative corrections to the (non singlet) polarized Drell Yan cross section for the production of a lepton pair with a nonzero qT. The helicity of the incoming states is arbitrary. In the case of double photon, results for the longitudinal asymmetries and on the pT behavior of the cross section are also given (to O({alpha}{sub em}{sup 2}{alpha}{sub s})) in the central rapidity region of the tagged photon.
Date: September 1, 1997
Creator: Chang, Sanghyeon; Coriano, C.; Field, R.D. & Gordon, L.E.
Partner: UNT Libraries Government Documents Department
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Next-to-leading order corrections to e{sup +}e{sup -} {yields} four jets

Description: I present a general purpose Monte Carlo program for calculating the next-to-leading order corrections to arbitrary four-jet quantities in electron-positron annihilation. In the current version of the program, some subleading in color terms are neglected. As an example, I calculate the four-jet rate in the Durham scheme as well as the Bengtsson-Zerwas angular distribution at O ({alpha}{sub s}{sup 3}) and compare the results to existing data.
Date: July 1, 1997
Creator: Signer, A.
Partner: UNT Libraries Government Documents Department
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RHIC spin program. Revision 07/97

Description: Colliding beams of high energy polarized protons at RHIC is an excellent way to probe the polarization of gluons, {anti u} and {anti d} quarks in a polarized proton. RHIC is the Relativistic Heavy Ion Collider being built now at Brookhaven in the ISABELLE tunnel. It is designed to collide gold ions on gold ions at 100 GeV/ nucleon. Its goal is to discover the quark-gluon plasma, and the first collisions are expected in March, 1999. RHIC will also make an ideal polarized proton collider with hig… more
Date: July 1, 1997
Creator: Bunce, G.
Partner: UNT Libraries Government Documents Department
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Properties of Z{sup 0} {yields} b{bar b}g events

Description: We present studies of e{sup +}e{sup -} {yields} b{bar b}g events recorded with SLC Large Detector(SLD) at the SLAC Linear Collider. The SLD precision vertex detector was exploited to select light quarks- (u,d, and s), c-, and b-enriched event samples. A comparison of the strong couplings of light, c, and b quarks was made using jet rates in these samples. We find: {alpha}{sub s}{sup uds} / {alpha}{sub s}{sup all} = 0.994 {+-} 0.018(stat) {+-} 0.025(syst), {alpha}{sub s}{sup c}/{alpha}{sub s}{su… more
Date: May 1, 1997
Creator: Oishi, N.
Partner: UNT Libraries Government Documents Department
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Non-equilibrium many body dynamics

Description: This Riken BNL Research Center Symposium on Non-Equilibrium Many Body Physics was held on September 23-25, 1997 as part of the official opening ceremony of the Center at Brookhaven National Lab. A major objective of theoretical work at the center is to elaborate on the full spectrum of strong interaction physics based on QCD, including the physics of confinement and chiral symmetry breaking, the parton structure of hadrons and nuclei, and the phenomenology of ultra-relativistic nuclear collisio… more
Date: September 22, 1997
Creator: Creutz, M. & Gyulassy, M.
Partner: UNT Libraries Government Documents Department
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Study of isospin correlation in high energy S + Pb and Pb + Pb interactions with a magnetic-interferometric-emulsion-chamber. Final report

Description: This report describes the research results of the study of high energy heavy-ion interactions and multi-cluster correlations at the University of Alabama in Huntsville (UAH). This study has been performed as the CERN experiments, EMU05, EMU09 and EMU16, and a part of the RHIC PHENIX and its MVD Collaboration work. Physics objectives and methods are described in chapters 1, 2, 3 and Appendices A1 and A2. The experimental set-up, measurements, an the data analyses at UAH are described in chapters… more
Date: December 12, 1997
Creator: Takahashi, Yoshiyuki
Partner: UNT Libraries Government Documents Department
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QCD results using the k{perpendicular} jet-finding algorithm in p{bar p} collisions at {radical}s = 1800 GeV

Description: An inclusive measurement of the jet mass as a function of jet p{sub {perpendicular}} has been made for jets with {vert_bar}{eta}{vert_bar} < 0.5. This measurement is the first in a hadron collider environment using the k {sub {perpendicular}} jet- finding algorithm. This analysis shows that the HERWIG Monte Carlo well reproduces the average jet mass for high p{sub {perpendicular}} jets. At lower p{sub {perpendicular}}, the data jets are 5-10% more massive. A second analysis has been performed w… more
Date: May 1, 1997
Creator: Lincoln, D. & Collaboration, DO
Partner: UNT Libraries Government Documents Department
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