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Review of Semileptonic Charm Decays

Description: The experimental status of D{sup 0} and D{sup +} semileptonic decays is reviewed and compared to model predictions. Topics covered are the form factor pole mass and decay rate for D {yields} Klv, the decay rate and form factor ratios for D {yields} K*lv, and, finally, the issue of modes other than Klv and K*lv. 4 refs., 5 tabs.
Date: January 1, 1991
Creator: Potter, D. M.
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Partner: UNT Libraries Government Documents Department
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Measurement of p p elastic scattering parameters at radical s = 1. 8 TeV

Description: A measurement of the total nuclear cross section, {sigma}{sub t}, the ratio of the real to the imaginary part of the forward nuclear elastic scattering amplitude, {rho}, and the nuclear slope parameter, B, for {bar p}p elastic scattering at {radical}{bar S} = 1.8 Te V, is presented. We find {sigma}{sub t} = 72.8 {plus minus} 3.1 mb, {rho} = 0.140 {plus minus} 0.69 and B = 16.99 {plus minus}.47 (GeV/c){sup {minus}2}. 5 refs., 13 figs., 2 tabs.
Date: August 1, 1991
Creator: Shukla, S.
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Partner: UNT Libraries Government Documents Department
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Rare K sup + decays in flight: Latest results and future plans

Description: E777 at the Brookhaven AGS has published a final branching ratio limit for the lepton family violating decay K{sup +} {yields} {pi}{sup +}{mu}{sup +}e{sup {minus}} of 2.1 {times} 10{sup {minus}10} (90% C.L.). New results based on approximately 500 events of the G.I. M. suppressed decay K{sup +} {yields} {pi}{sup +}e{sup +}e{sup {minus}} have yielded a branching ratio of (2.75 {plus minus} 0.23 {plus minus} 0.13) {times} 10{sup {minus}7} assuming a vector interaction with, a form factor = 0.105 … more
Date: January 1, 1991
Creator: Alliegro, C.; Zeller, M. E. (Yale Univ., New Haven, CT (United States)); Campagnari, C. (Chicago Univ., IL (United States)); Chaloupka, V.; Lubatti, H. J.; Zhao, T. (Washington Univ., Seattle, WA (United States)) et al.
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Partner: UNT Libraries Government Documents Department
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The electromagnetic scenario for Higgs production in large colliders

Description: We outline the formalism required to calculate coherent pair production from electromagnetic fields. Applications are made to the production of the Higgs boson at large colliders, with particular attention to the problem of discriminating against backgrounds. Electromagnetic production does indeed appear to be a competitive probe of the symmetry-breaking sector. 14 refs., 17 figs., 2 tabs.
Date: January 1, 1991
Creator: Bottcher, C. & Strayer, M. R.
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Partner: UNT Libraries Government Documents Department
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Electromagnetic wave scattering from magnetic fluctuations in tokamaks

Description: Cross sections are calculated for electromagnetic wave scattering and mode transformation from magnetic and density fluctuations in the vicinity of the principal electron cutoffs and resonances in a homogeneous plasma. For the special case of scattering perpendicular to the magnetic field, density fluctuations scatter ordinary to ordinary and extraordinary to extraordinary modes -- but cannot transform these modes. On the other hand, magnetic fluctuations perpendicular to the field can transfor… more
Date: July 1, 1991
Creator: Vahala, L. (Old Dominion Univ., Norfolk, VA (United States). Dept. of Electrical and Computer Engineering); Vahala, G. (College of William and Mary, Williamsburg, VA (United States). Dept. of Physics) & Bretz, N. (Princeton Univ., NJ (United States). Plasma Physics Lab.)
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Segregation of quarks within the neutron

Description: Measurements of the nucleon form factor and structure function seem to indicate an inhomogeneous distribution of flavor, charge and spin within the nucleon. It is argued that the ordinary three-quark model with a spin-spin force of the type suggested by QCD can explain the inhomogeneity as seen at different resolutions. This agreement suggests a specific bound quark picture of the nucleon structure with a positive core of u and d quarks in a spin-O state of ms radius 0.17 {plus minus} 0.01 fm{s… more
Date: January 1, 1991
Creator: Dziembowski, Z.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Chiral perturbation theory with nucleons

Description: I review the constraints posed on the interactions of pions, nucleons and photons by the spontaneously broken chiral symmetry of QCD. The framework to perform these calculations, chiral perturbation theory, is briefly discussed in the meson sector. The method is a simultaneous expansion of the Greens functions in powers of external moments and quark masses around the massless case, the chiral limit. To perform this expansion, use is made of a phenomenological Lagrangian which encodes the Ward-i… more
Date: September 1, 1991
Creator: Meissner, U.G.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Spin observables and electromagnetic excitations of nucleon resonances

Description: We discuss the theoretical problems involved in relating the {gamma}N {yields} {pi}N and N(e,e{prime}{pi}) data to the {gamma}N {yields} {Delta}, N* transition form factors. The experimental accuracies needed to explore {gamma}N {yields} {Delta} E2 and charge form factors from p(e,e{prime}{pi}{sup 0}) spin observables A{sub TT} and A{sub TL} are presented. 4 refs., 1 fig.
Date: January 1, 1991
Creator: Lee, T.S.H. (Argonne National Lab., IL (USA)) & Nozawa, S. (Queen's Univ., Kingston, ON (Canada))
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Partner: UNT Libraries Government Documents Department
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The neutral kaon program at Fermilab and recent E731 results

Description: Currently, Fermilab has a long-range program in neutral kaon physics which covers a wide variety of physics topics. In this report, I will be discussing the latest results from experiment E731 on the radiative decay of neutral kaons K{sub L,S} {yields} {pi}{sup +}{pi}{sup {minus}} {gamma}. These results include the first measurement of two new CP violation parameters: {eta}{sub +} {sub {minus}}{gamma} = (2.60{plus minus}0.54{plus minus}0.21) {center dot} 10{sup {minus}3}, and {phi}{sub +}{sub {… more
Date: September 1, 1991
Creator: Ramberg, E.J.
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Partner: UNT Libraries Government Documents Department
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Measuring the quark contribution to the proton spin through. nu. p yields. nu. p

Description: The LSND (Liquid Scintillator Neutrino Detector) experiment will be performed at LAMPF in the next several years. The main goal of the experiment is to search for {nu}{sub {mu}}-{nu}{sub e} oscillations with high sensitivity; however, an increasingly important by-product of this search is to measure {nu}p {yields} {nu}p elastic scattering and determine the strange quark contribution, {Delta}s, to the spin of the proton. With the 800-MeV proton energy of LAMPF, neutrinos are produced from pion d… more
Date: January 1, 1991
Creator: Louis, W.C.
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Partner: UNT Libraries Government Documents Department
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Measuring strangeness matrix elements of the nucleon

Description: Experiments are proposed to measure various strangeness matrix elements of the nucleon. Examples are electro- and neutrino- production of phi mesons and the difference between neutrino and antineutrino scattering from isospin zero targets, e.g., deuterons.
Date: January 1, 1991
Creator: Henley, E. M.; Pollock, S. J. (Washington Univ., Seattle, WA (United States)); Krein, G. (Washington Univ., Seattle, WA (United States) Instituto de Fisica Teorica (IFT), Sao Paulo, SP (Brazil)) & Williams, A. G. (Washington Univ., Seattle, WA (United States) Florida State Univ., Tallahassee, FL (United States))
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Heavy-quark physics in quantum chromodynamics

Description: Heavy quarks can expose new symmetries and novel phenomena in QCD not apparent in ordinary hadronic systems. In these lectures I discuss the use of effective-Lagrangian and light-cone Fock methods to analyze exclusive heavy hadron decays such as {Upsilon} {yields} p{bar p} and B {yields} {pi}{pi}, and also to derive effective Schroedinger and Dirac equations for heavy quark systems. Two contributions to the heavy quark structure functions of the proton and other light hadrons are identified: an… more
Date: April 1, 1991
Creator: Brodsky, Stanley J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Chiral symmetry, axial anomaly and the structure of hot QCD

Description: This lecture is composed of three parts. (1) Heavy quark and gluon contents of light hadrons, (II) anomalous gluon content of the nucleon, and (III) hot and dense QCD. Non-valence structures of nucleon due to the OZI violation are extensively discussed in (I) and (II), and non-perturbative aspects of the quark-gluon plasma are reviewed in (III). 41 refs.
Date: October 1, 1991
Creator: Hatsuda, Tetsuo.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Chiral perturbation theory with nucleons

Description: I review the constraints posed on the interactions of pions, nucleons and photons by the spontaneously broken chiral symmetry of QCD. The framework to perform these calculations, chiral perturbation theory, is briefly discussed in the meson sector. The method is a simultaneous expansion of the Greens functions in powers of external moments and quark masses around the massless case, the chiral limit. To perform this expansion, use is made of a phenomenological Lagrangian which encodes the Ward-i… more
Date: September 1, 1991
Creator: Meissner, U. G.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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The Brookhaven rare kaon decay program

Description: The results of the current generation of rare kaon decay experiments at Brookhaven National Laboratory are reviewed. The present status of and future plans for such experiments are discussed.
Date: January 1, 1991
Creator: Littenberg, L. S.
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Partner: UNT Libraries Government Documents Department
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QCD Sum Rule Calculation of the Isgur-Wise Form Factor

Description: Within the QCD sum rule approach, we develop a formalism that enables one to calculate the form factors of the heavy-light mesons in the m(sub)Q -> infinity limit. It is shown that the behaviour of the universal Isgur-Wise form factor is determined by the quark propagation function in imaginary time.
Date: October 1, 1991
Creator: Radyushkin, Anatoly
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Partner: UNT Libraries Government Documents Department
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The axial anomaly and the dynamical breaking of chiral symmetry

Description: Using the quark triangle diagram for the Adler-Bell-Jackiw axial anomaly, we calculate the form factor for the {gamma}{sup *}{pi}{sup 0}{yields}{gamma} transition. This form factor depends on the quark mass, and we predict the right behavior with m{sub q}{approx_equal}250 MeV, the same quark mass generated by the dynamical breaking of chiral symmetry through a Nambu-Jona-Lasinio mechanism.
Date: October 1, 1991
Creator: Gross, Franz; Ito, Hiroshi & Buck, Warren
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Partner: UNT Libraries Government Documents Department
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Electromagnetic properties of the pion as a composite nambu-goldstone boson

Description: Motivated by the Nambu-Jona-Lasinio model of light mesons, we introduce a covariant separable interaction to model the structure of relativistic quark-antiquark systems.The Schwinger-Dyson equation for the quark self-energy is solved analytically, generating a dynamical quark mass through spontaneous breaking of chiral symmetry, and yielding a pion which has zero mass in the chiral limit.The Bethe-Salpeter vertex function for this q{vec}q pion, which has a momentum distribution and composite st… more
Date: October 1, 1991
Creator: Gross, Franz; Ito, Hiroshi & Buck, Warren
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Partner: UNT Libraries Government Documents Department
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QCD sum rule calculation of the isgur-wise nonlogical condensates

Description: Within the QCD sum rule approach, we develop a formalism that enables one to calculate the form factors of the heavy-light mesons in the m{sub Q} {yields} {infinity} limit. It is shown that the behavior of the universal Isgur-Wise form factor is determined by the quark propagation function in imaginary time.
Date: October 1, 1991
Creator: Radyushkin, Anatoly
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Partner: UNT Libraries Government Documents Department
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Physics at CEBAF with High Resolution Spectrometers

Description: We present here the physics program planned for Hall A at CEBAF.It encompasses exclusive as well as inclusive electromagnetic measurements requiring both high precision and accuracy.The program includes measurements of the elementary form factors of the nucleon, systematic studies of the few nucleon systems (d, (sup)3.4 He), high momentum structure of nuclei, their structure at high Q^2 to look for hadronization and quark effects, spin response of nuclei via (vector-e, e', vector-p) reactions a… more
Date: January 1, 1991
Creator: Saha, Arunava
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Nonlocal Condensates and QCD Sum Rules for the Pion Form Factor

Description: We extend the QCD sum rule analysis of the pion electromagnetic form factor F(sub)pi(Q^2) into the region of moderately large momentum transfers 3GeV^2 < Q^2 < 10 GeV^2, where one should take into account the effects due to nonzero average virtuality of the vacuum quarks and gluons.
Date: October 1, 1991
Creator: Radyushkin, Anatoly & Radyushkin, Anatoly
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Partner: UNT Libraries Government Documents Department
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Heavy quark symmetries and the decays baryon antibaryon

Description: We enumerate the form factors necessary to describe the two-body baryonic decays of B mesons.We use the symmetries of the heavy quark effective theory to arrive at some relations among these form factors, when at least one of the daughter baryons is heavy.
Date: October 1, 1991
Creator: Roberts, Winston; Roberts, Winston & Ryzak, Z.
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Partner: UNT Libraries Government Documents Department
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Current conservation and electromagnetic interaction currents for non-relativistic systems

Description: It is shown how to construct non-relativistic interaction currents which satisfy current conservation. The construction permits the use of different electromagnetic form factors for the pion, nucleon, and contact contributions, and therefore also permits the use of either G{sub E} of F{sub 1}. The numerical importance of this freedom for calculations of the electromagnetic form factors of {sup 3}He is studied, and found to be significant in some cases.
Date: May 1, 1991
Creator: Gross, Franz & Gross, Franz
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Partner: UNT Libraries Government Documents Department
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