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Hadroproduction of charm at Fermilab E769

Description: Experiment E769 at Fermilab obtained charm hadroproduction data during the 1987-88 Fixed Target running period with a 250 GeV hadron beam incident on thin target foils of Be, Al, Cu, and W. From an analysis of 25% of the recorded 400M trigger sample we have explored the Feynman x, p{sub t}{sup 2} and the atomic number dependence of charm quark production using samples of D{sup +} and D{sup 0} mesons. 7 refs., 4 figs.
Date: November 15, 1990
Creator: Alves, G. A.; Anjos, J. C.; de Mello Neto, J. R. T.; de Miranda, J. M.; da Motta, H.; dos Reis, A. C. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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High Energy Physics at Tufts University. Progress report, 1992--1993

Description: This report discusses the following topics: Fermilab fixed target experiments; Soudan II nucleon decay project; Physics at the proton-antiproton collider at {radical}s = 1.8 TeV; The Solenoidal Detector for the supercollider; Neutrino telescope proposal; Polarization in massive quark and hadron production; Production characteristics of top quarks; Scattering, spin dependence and mass corrections in Skyrmion models; and computation and networking.
Date: July 15, 1993
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Associated Higgs Boson Production With Heavy Quarks.

Description: The production of a Higgs boson in association with a pair of e quarks will play a very important role at both hadron and lepton colliders. We review the status of theoretical predictions and their relevance to Higgs boson studies, with particular emphasis on the recently calculated NLO QCD corrections to the inclusive cross section for p{bar p}, pp {yields} t{bar t}h. We conclude by briefly discussing the case of exclusive b{bar b}h production and the potential of this process in revealing sig… more
Date: March 15, 2003
Creator: Dawson, S.; Orr, L. H.; Reina, L. & Wackeroth, D.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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High Energy Physics at Tufts University

Description: This report discusses the following topics: Neutrino Interactions in the 15-foot Bubble Chamber; Pion and Kaon Production of Charm and Charm-Strange States; Study of Heavy Flavors at the Tagged Particle Spectrometer; Neutrino Oscillations at the Fermilab Main Injector; Soudan II Nucleon Decay Project; Physics at the Antiproton-Proton Collider at {radical}{bar s} = 1.8 TeV; Designing the Solenoidal Detector for the Supercollider; Neutrino Telescope Proposal; Polarization in Inclusive Hyperon Pro… more
Date: July 15, 1992
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Top Quark Anomalous Couplings at the International Linear Collider

Description: We present a study of the experimental determination of the forward-backward asymmetry in the process e{sup +}e{sup -} {yields} t{bar t} and in the subsequent t {yields} Wb decay, studied in the context of the International Linear Collider. This process probes the elementary couplings of the top quark to the photon, the Z and the W bosons at a level of precision that is difficult to achieve at hadron colliders. Measurement of the forward-backward asymmetry requires excellent b quark identificat… more
Date: August 15, 2011
Creator: Devetak, Erik; Nomerotski, Andrei & Peskin, Michael
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Measurements of observables in the pion-nucleon system, nuclear a- dependence of heavy quark production and rare decays of D and B mesons. Progress report, 1 December, 1990--15 February, 1992

Description: This report discusses research on the following topics: pion-nucleon interactions; detector tomography facility; nuclear dependence of charm and beauty quark production and a study of two-prong decays of neutral D and B mesons; N* collaboration at CEBAF; and pilac experiments. (LSP)
Date: February 15, 1992
Creator: Sadler, M. E. & Isenhower, L. D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Light quarks and small X physics

Description: The significance of the low k{perpendicular} part of the Lipatov equation for the QCD soft Pomeron is discussed. It is then argued that light quarks are essential for the emergence of confinement and a Pomeron with the right physical properties. The implications for small {times} parton distributions are considered.
Date: June 15, 1992
Creator: White, A. R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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High Energy Physics at Tufts University. Progress report, 1991--1992

Description: This report discusses the following topics: Neutrino Interactions in the 15-foot Bubble Chamber; Pion and Kaon Production of Charm and Charm-Strange States; Study of Heavy Flavors at the Tagged Particle Spectrometer; Neutrino Oscillations at the Fermilab Main Injector; Soudan II Nucleon Decay Project; Physics at the Antiproton-Proton Collider at {radical}{bar s} = 1.8 TeV; Designing the Solenoidal Detector for the Supercollider; Neutrino Telescope Proposal; Polarization in Inclusive Hyperon Pro… more
Date: July 15, 1992
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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AdS/QCD and Light Front Holography: A New Approximation to QCD

Description: The combination of Anti-de Sitter space (AdS) methods with light-front holography leads to a semi-classical first approximation to the spectrum and wavefunctions of meson and baryon light-quark bound states. Starting from the bound-state Hamiltonian equation of motion in QCD, we derive relativistic light-front wave equations in terms of an invariant impact variable {zeta} which measures the separation of the quark and gluonic constituents within the hadron at equal light-front time. These equat… more
Date: February 15, 2010
Creator: Brodsky, Stanley J. & de Teramond, Guy
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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HEAVY QUARKS AT RHIC FROM PARTON TRANSPORT THEORY.

Description: There are several indications that an opaque partonic medium is created in energetic Au+Au collisions ({radical}s{sub NN} {approx} GeV/nucleon) at the Relativistic Heavy Ion Collider (RHIC). At the extreme densities of {approx} 10-100 times normal nuclear density reached even heavy-flavor hadrons are affected significantly. Heavy-quark observables are presented from the parton transport model MPC, focusing on the nuclear suppression pattern, azimuthal anisotropy (''elliptic flow''), and azimuth… more
Date: May 15, 2006
Creator: MOLNAR, D.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Proceedings of RIKEN BNL Research Center Workshop Entitled - Domain Wall Fermions at Ten Years (Volume 84)

Description: The workshop was held to mark the 10th anniversary of the first numerical simulations of QCD using domain wall fermions initiated at BNL. It is very gratifying that in the intervening decade widespread use of domain wall and overlap fermions is being made. It therefore seemed appropriate at this stage for some ''communal introspection'' of the progress that has been made, hurdles that need to be overcome, and physics that can and should be done with chiral fermions. The meeting was very well at… more
Date: March 15, 2007
Creator: Blum, T. & Soni, A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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A proposal to study particle production spectra and multiplicities in high energy hadron-hadron collisions, and for a beam survey and quark search

Description: We propose an experimental study at the new 500 GeV accelerator of the differential cross-section for particle production in hadron-hadron collisions. The projectile, and the observed single particle, will range over all combinations of positive and negative {pi}, K and p, with momenta extending up to the highest available. Enough of the secondary particle momentum range will be covered to permit us to determine by integration the multiplicity of the produced particle. Single particles will be … more
Date: June 15, 1970
Creator: Beier, E.W.; Kreinick, D.L.; Weisberg, H. & U., /Pennsylvania
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Illuminating the 1/x Moment of Parton Distribution Functions

Description: The Weisberger relation, an exact statement of the parton model, elegantly relates a high-energy physics observable, the 1/x moment of parton distribution functions, to a nonperturbative low-energy observable: the dependence of the nucleon mass on the value of the quark mass or its corresponding quark condensate. We show that contemporary fits to nucleon structure functions fail to determine this 1/x moment; however, deeply virtual Compton scattering can be described in terms of a novel F1/x(t)… more
Date: October 15, 2007
Creator: Brodsky, Stanley J.; Llanes-Estrada, Felipe J. & Szczepaniak, Adam P.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Measurement of Angle beta with Time-dependent CPAsymmetry in B0 to K+K-K0 Decays

Description: In the Standard Model (SM) of particle physics, the phase of the Cabibbo-Kobayashi-Maskawa (CKM) quark-mixing matrix [1, 2] is the only source of CP violation in the quark sector. Due to the interference between mixing and decay, this phase can be observed in measurements of time-dependent CP asymmetries of B{sup 0} mesons. In the SM, CP asymmetries in b {yields} s{bar s}s decays, such as B{sup 0} {yields} K{sup +}K{sup -}K{sup 0}, are expected to be nearly equal to those observed in tree-domin… more
Date: February 15, 2007
Creator: Di Marco, Emanuele
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Lattice QCD Thermodynamics First 5000 Trajectories

Description: These results represent the first LQCD analysis for approximately 5000 trajectories with each of the p4rhmc and milc codes, with some of the lower temperature runs having fewer. Both runs were for lattice dimensions of 32{sup 3}x8. Some 32{sup 4} T=0 jobs were also run for p4rhmc. The p4 calculation was performed with v2.0 QMP{_}MPI.X (semi-optimized p4 code using qmp over mpi) and milc version of the su3 rhmc susc eos executable dated Mar 1, 2007 on ubgl in the /usr/gapps/hip/qcd/milc/bin subd… more
Date: March 15, 2007
Creator: Soltz, R. & Gupta, R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Phases of Augmented Hadronic Light-Front Wave Functions

Description: It is an important question whether the final/initial state gluonic interactions which lead to naive-time-reversal-odd single-spin asymmetries and diffraction at leading twist can be associated in a definite way with the light-front wave function hadronic eigensolutions of QCD. We use light-front time-ordered perturbation theory to obtain augmented light-front wave functions which contain an imaginary phase which depends on the choice of advanced or retarded boundary condition for the gauge pot… more
Date: February 15, 2010
Creator: Brodsky, Stanley J.; Pasquini, Barbara; Xiao, Bo-Wen & Yuan, Feng
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Past, present and future highlights in top and higgs physics from the CDF experiment

Description: The 1992-1995 running of the Fermilab Tevatron (the so-called Run 1) ended with many important physics goals accomplished, including the discovery of the top quark, and the anticipation of many further questions be to answered in the future. In March 2002, after many detector upgrades by both the CDF and D0 experiments, and significant upgrades of the accelerator itself, the Tevatron Run 2 began (after a detector commissioning run) with the ultimate goal of discovering the Higgs boson. Here, we… more
Date: December 15, 2003
Creator: Kruse, M. C.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Non-universal SUSY breaking, hierarchy and squark degeneracty

Description: I discuss non-trivial effects in the soft SUSY breaking terms which appear when one integrates out heavy fields. The effects exist only when the SUSY breaking terms are non-universal. They may spoil (1) the hierarchy between the weak and high-energy scales, or (2) degeneracy among the squark masses even in the presense of a horizontal symmetry. I argue, in the end, that such new effects may be useful in probing physics at high-energy scales from TeV-scale experiments.
Date: March 15, 1995
Creator: Murayama, Hitoshi
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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To quark mass measurements at the Tevatron

Description: We present two new measurements of the top-quark mass. Using the same methodology applied in Run I, the CDF experiment uses 72 pb{sup -1} of Run II data to measure M{sub top} = 171.2 {+-} 13.4{sub stat} {+-} 99{sub syst} GeV/c{sup 2}. On the other hand, the D0 experiment, using 125 pb{sup -1} from Run I, and applying a new method that extracts information from data through a direct calculation of a probability for each event, obtains M{sub top} = 180.1 {+-} 3.6{sub stat} {+-} 4.0{sub syst} GeV/… more
Date: October 15, 2003
Creator: Canelli, Maria Florencia
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Bottom production

Description: In the context of the LHC experiments, the physics of bottom flavoured hadrons enters in different contexts. It can be used for QCD tests, it affects the possibilities of B decays studies, and it is an important source of background for several processes of interest. The physics of b production at hadron colliders has a rather long story, dating back to its first observation in the UA1 experiment. Subsequently, b production has been studied at the Tevatron. Besides the transverse momentum spect… more
Date: March 15, 2000
Creator: Baines, J.; Baranov, S. P.; Bartalini, P.; Bay, A.; Bouhova, E.; Cacciari, M. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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The Compact Muon Solenoid Heavy Ion program

Description: The Pb-Pb center of mass energy at the LHC will exceed that of Au-Au collisions at RHIC (Relativistic Heavy Ion Collider) by nearly a factor of 30, providing exciting opportunities for addressing unique physics issues in a completely new energy domain. The interest of the Heavy Ion (HI) Physics at LHC is discussed in more detail in the LHC-USA white paper and the Compact Muon Solenoid (CMS) Heavy Ion proposal. A few highlights are presented in this document. Heavy ion collisions at LHC energies… more
Date: December 15, 2005
Creator: Yepes, Dr. Pablo
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Weak matrix elements in the large N{sub c} limit

Description: The matrix elements of the four quark operators needed to predict many weak interaction processes can be evaluated using the large N{sub c} limit of quantum chromodynamics. At leading order in the large N{sub c} expansion, the weak matrix elements of four quark operators factorize into independent matrix elements of two quark operators, a common approximation being used today. At the next leading order, the weak matrix elements acquire the leading scale and scheme dependence expected for these … more
Date: October 15, 1999
Creator: Bardeen, William A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Measurements of observables in the pion-nucleon system, nuclear a- dependence of heavy quark production and rare decays of D and B mesons

Description: This report discusses research on the following topics: pion-nucleon interactions; detector tomography facility; nuclear dependence of charm and beauty quark production and a study of two-prong decays of neutral D and B mesons; N* collaboration at CEBAF; and pilac experiments. (LSP)
Date: February 15, 1992
Creator: Sadler, M.E. & Isenhower, L.D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Light-Front Holography and the Light-Front Schrodinger Equation

Description: One of the most important nonperturbative methods for solving QCD is quantization at fixed light-front time {tau} = t+z=c - Dirac's 'Front Form'. The eigenvalues of the light-front QCD Hamiltonian predict the hadron spectrum and the eigensolutions provide the light-front wavefunctions which describe hadron structure. More generally, we show that the valence Fock-state wavefunctions of the light-front QCD Hamiltonian satisfy a single-variable relativistic equation of motion, analogous to the non… more
Date: August 15, 2012
Creator: Brodsky, Stanley J. & de Teramond, Guy
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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