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Structure functions: Their status and implications

Description: I discuss the current status of structure functions. Attention is given to the uncertainties in them and the implications of these uncertainties for experimental predictions. I indicate which experiments are capable of removing these uncertainties. 17 refs., 17 figs., 1 tab.
Date: September 29, 1988
Creator: Hinchliffe, I.
Partner: UNT Libraries Government Documents Department
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Two-photon physics

Description: A new experimental frontier has recently been opened to the study of two photon processes. The first results of many aspects of these reactions are being presented at this conference. In contrast, the theoretical development of research ito two photon processes has a much longer history. This talk reviews the many different theoretical ideas which provide a detailed framework for our understanding of two photon processes.
Date: October 1, 1981
Creator: Bardeen, W.A.
Partner: UNT Libraries Government Documents Department
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Transverse spin observables in chromodynamics

Description: Quantum Chromodynamics confronts a harsh series of tests in the attempt to formulate a comprehensive approach to the calculation of transverse spin observables. The basic obstacles to understanding transverse spin can be illustrated by considering the transverse structure function g{sub T}(x, Q{sup 2}) = g{sub 1}(x, Q{sup 2}) + g{sub 2}(x, Q{sup 2}), extracted from deep-inelastic scattering using a polarized lepton and a polarized proton. The inadequacy of the transverse-spin basis for quarks a… more
Date: December 1, 1989
Creator: Sivers, D.
Partner: UNT Libraries Government Documents Department
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Hadron-hadron physics at high energy and luminosity

Description: I review some recent theoretical issues relevant to the physics of hadron-hadron collisions. I discuss processes where either energy or luminosity is the most important feature and emphasize the need for experiments at luminosities of 10{sup 33}cm{sup -2}sec{sup 1} if the full range of physics options is to be thoroughly explored. 22 refs., 10 figs.
Date: November 8, 1989
Creator: Hinchliffe, I.
Partner: UNT Libraries Government Documents Department
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Open and hidden charm muoproduction. [209 GeV]

Description: New results are presented on open and hidden charm and bottom production by 209-GeV muons interacting in a magnetized steel calorimeter. The upper limit on the production of T states by muons is sigma(..mu..N ..-->.. ..mu..UPSILONX)B(UPSILON ..-->.. ..mu mu..) < 22 x 10/sup -39/ cm/sup 2/ (90% confidence level). The distributions of elastically produced psi's are consistent with s-channel helicity conservation (SCHC) and disagree with psi dominance. From analysis of dimuon final states the cros… more
Date: September 1, 1980
Creator: Clark, A.R.; Johnson, K.J. & Kerth, L.T.
Partner: UNT Libraries Government Documents Department
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Lattice calculations of electroweak decay amplitudes

Description: I review the progress made during the last year in lattice calculations of weak and electromagnetic amplitudes. 32 refs., 9 figs., 2 tabs.
Date: November 1, 1989
Creator: Sharpe, S.R.
Partner: UNT Libraries Government Documents Department
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Measurement of the neutron spin structure function---Test of the Bjorken sum rule

Description: As experiment to measure the neutron spin-dependent structure function g{sub 1}{sup n} (x) over a range in x from 0.04 to 0.7 and with Q{sup 2} > 1 (GeV/c){sup 2} is presented. The experiment consists of scattering a longitudinally polarized electron beam from the Stanford Linear Accelerator off a polarized {sup 3}He target and detecting scattered electrons in two magnetic spectrometers. The experiment will provide a critical test of the Bjorken sum rule and valuable information in understandin… more
Date: August 1, 1991
Creator: Petratos, G.G.
Partner: UNT Libraries Government Documents Department
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Some physical aspects of higher twist

Description: A brief description of some of the physical origins of higher twist terms and their possible relevance to data is given. 13 references, 7 figures.
Date: May 1, 1980
Creator: Blankenbecler, R.
Partner: UNT Libraries Government Documents Department
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Tests of perturbative quantum chromodynamics in photon-photon collisions

Description: The production of hadrons in the collision of two photons via the process e/sup +/e/sup -/ ..-->.. e/sup +/e/sup -/X can provide an ideal laboratory for testing many of the features of the photon's hadronic interactions, especially its short-distance aspects. That part of two-photon physics which is particularly relevant to tests of perturbative QCD is reviewed here. 6 figures.
Date: January 1, 1979
Creator: Brodsky, Stanley J.
Partner: UNT Libraries Government Documents Department
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Normalizing the renormalization group in deep inelastic leptoproduction. CTP No. 878

Description: The quark-bag model is used to calculate the nucleon matrix elements of local twist-two operators. Bag matrix elements applicable to low Q/sup 2/ are evolved by use of QCD perturbation theory to a value of Q/sup 2/ large enough that the data can be expected to be dominated by twist-two. Nonsinglet moments of F/sub 3/ are plotted. Although only twist-two was studied, the work has implications for higher twist. It is concluded that either the twist-two operator matrix element is Q/sup 2/ dependen… more
Date: September 1, 1980
Creator: Jaffe, R.L.
Partner: UNT Libraries Government Documents Department
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nu. N,. mu. N interactions: structure functions, higher twist

Description: Data on deep inelastic scattering of leptons by nucleons and nuclei have been accumulated for several years. Results exist from several experiments with electron, muon, neutrino beams. In this talk I shall review the most recent experiments which measured nucleon structure functions with ..nu.. and ..mu.. beams. In particular, I will summarize the results on R = sigma/sub L//sigma/sub T/ measurement, on F/sub 2/(x,Q/sup 2/), and xF/sub 3/(x,Q/sup 2/), and their interpretation in terms of QCD, i… more
Date: October 1, 1981
Creator: Matteuzzi, C.
Partner: UNT Libraries Government Documents Department
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Calculations of the ground state of sup 16 O

Description: One of the central problems in nuclear physics is the description of nuclei as systems of nucleons interacting via realistic potentials. There are two main aspects of this problem: specification of the Hamiltonian, and calculation of the ground states of nuclei with the given interaction. Realistic interactions must contain both two- and three-nucleon potentials and these potentials have a complicated non-central operator structure consisting, for example, of spin, isospin and tensor dependence… more
Date: January 1, 1989
Creator: Pieper, S. C.
Partner: UNT Libraries Government Documents Department
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EMC Effect

Description: A review is presented of data and theoretical interpretations of the nuclear dependence of quark and antiquark distributions as observed in the deep inelastic scattering of neutrinos and charged leptons from nuclei. After a summary of the experimental situation and a survey of the broad spectrum of proposed explanations, I concentrate on the Q/sup 2/-rescaling approach and on interpretations in terms of conventional nuclear physics. The review concludes with a list of desirable future experimen… more
Date: June 1, 1986
Creator: Berger, E. L.
Partner: UNT Libraries Government Documents Department
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Inclusive quasielastic and deep inelastic electron scattering at high energies

Description: With high electron energies a kinematic regime can be reached where it will be possible to separate quasielastic and deep inelastic scattering. We present a short description of these processes which dominate the inclusive spectrum. Using the highest momentum transfer data available to guide our estimates, we give the kinematic requirements and the cross sections expected. These results indicate that inclusive scattering at high q has a yet unfilled potential. 18 refs., 13 figs.
Date: January 1, 1990
Creator: Day, D.B.
Partner: UNT Libraries Government Documents Department
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Initial-state interactions, factorization, and the Drell-Yan process

Description: It is shown that initial state interactions violate the factorization conjecture for the Drell-Yan process order by order in perturbation theory. Also, the effects of elastic and inelastic initial state interactions on the observed cross sections are discussed.
Date: December 1, 1981
Creator: Bodwin, G. T.; Brodsky, S. J. & Lepage, G. P.
Partner: UNT Libraries Government Documents Department
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Exclusive processes and hadron dynamics at short distances

Description: The predictions of perturbative QCD for a number of areas of hadron dynamics are discussed, including exclusive processes at large momentum transfer, the endpoint behavior of hadronic structure functions, and the Fock state structure of hadron wave functions, especially their behavior at short distances. New results for exclusive two-photon processes, the normalization of high-twist contributions to the meson structure function, and the calculation of the valence Fock state probability of the p… more
Date: September 1, 1980
Creator: Brodsky, S.J. & Lepage, G.P.
Partner: UNT Libraries Government Documents Department
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The proton's spin: A quark model perspective

Description: Magnetic moments and g{sub A}/g{sub V} provide information on the correlations among quark spins and flavors in the proton. I compare this information with the deep inelastic polarized data from EMC which has been claimed to show that very little of the proton's spin is due to the quarks. The possibility that there is significant polarization of strange quarks within protons is discussed. 38 refs.
Date: January 1, 1989
Creator: Close, F. E.
Partner: UNT Libraries Government Documents Department
open access

A perspective on lepton-photon physics

Description: This paper reviews some key experiments of the past in which the same basic physical processes are attacked both through lepton-photon interaction and by using hadron machines as primary tools. Not surprisingly, it is concluded that the basic distinction between lepton-photon physics and elementary particle physics in general is unreal but that the tools and methodology can be very different indeed. A look is then taken into the expected future evolution of particle accelerators. Existing accel… more
Date: November 1, 1989
Creator: Panofsky, W.K.H.
Partner: UNT Libraries Government Documents Department
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Xi-Scaling

Description: A class of purely kinematical corrections to xi-scaling is exposed. These corrections are inevitably present in any realistic hadron model with spin and gauge invariance and lead to phenomenologically important M/sub hadron//sup 2//Q/sup 2/ corrections to Nachtmann moments.
Date: April 1, 1980
Creator: Gunion, J. F.
Partner: UNT Libraries Government Documents Department
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Lepton-pair production in hadron-nucleus collisions

Description: Physics motivations for precision measurements of lepton pair production in nuclei are discussed. Preliminary results from Fermilab Experiment E772 are presented. The relevance of these results to the EMC effect and to J/{psi} suppression in heavy ion collisions is also discussed. 34 refs., 17 figs.
Date: January 1, 1989
Creator: Moss, J. M.; Peng, J. C.; Alde, D. M.; Baer, H. W.; Carey, T. A.; Garvey, G. T. et al.
Partner: UNT Libraries Government Documents Department
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Status of perturbative QCD

Description: In this talk is discussed, within the framework of perturbative QCD, four topics which have received theoretical attention in the last year. They are: (1) jets at the CERN Sp anti p S collider, (2) power corrections to leptoproduction, (3) hard scattering off nuclear targets, and (4) the photon structure function. 28 references.
Date: August 1, 1983
Creator: Ellis, R.K.
Partner: UNT Libraries Government Documents Department
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Particle production through two-photon processes in relativistic heavy-ion colliders

Description: Particle production via two-photon processes in relativistic heavy-ion colliders is discussed. We consider the coherent production, including its impact parameter dependence, and incoherent production. Particular attention is given to Higgs boson production in the energy regime of the LHC and the SSC. 15 refs., 7 figs., 1 tab.
Date: January 1, 1991
Creator: Wu, J.-S.; Bottcher, C.; Strayer, M.R. (Oak Ridge National Lab., TN (United States)) & Shakin, C.M. (Brooklyn Coll., NY (United States))
Partner: UNT Libraries Government Documents Department
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Determination of the nucleon structure using the weak neutral current

Description: An experimental determination of the neutral current structure functions of the nucleon is obtained by measuring the ratio of the neutral current x distribution to the charged current x distribution. The analysis is based on deep inelastic neutrino nucleon scattering data gathered in a massive fine-grained neutrino detector exposed to a narrow band neutrino beam at Fermilab. 12 refs., 2 figs., 2 tabs.
Date: July 1, 1985
Creator: Bogert, D.; Burnstein, R.; Fisk, R.; Fuess, S.; Morfin, J. G.; Ohska, T. et al.
Partner: UNT Libraries Government Documents Department
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Deep inelastic muon scattering with hadron detection

Description: The physics motivation and experimental apparatus of FNAL E665 are described. E665 is a new experiment to study the hadrons in coincidence with muons deep inelastically scattered from nuclei. One of the goals of the experiment is to examine nuclear medium effects not only on the baryon quark distributions (the EMC effect) but also on the process of hadronization in high energy collisions. 17 refs., 5 figs.
Date: January 1, 1985
Creator: Geesaman, D.F. & Green, M.C.
Partner: UNT Libraries Government Documents Department
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