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Discussion session: nucleon- and antinucleon-nucleus inelastic scattering and charge exchange

Description: This short article summarizes one part of the discussion session concerning nucleon- and antinucleon-nucleus inelastic scattering and charge exchange. Assigned an unconstrained role somewhere between that of rapporteur and ''rioteur'' I've decided to use a few highlights of the conference to stage a number of personal opinions regarding our current status in this game and where we might be going. 20 refs.
Date: January 1, 1985
Creator: Carey, T.A.
Partner: UNT Libraries Government Documents Department

Shlaer-Mellor object-oriented analysis and recursive design, an effective modern software development method for development of computing systems for a large physics detector

Description: After evaluation of several modern object-oriented methods for development of the computing systems for the PHENIX detector at RHIC, we selected the Shlaer-Mellor Object-Oriented Analysis and Recursive Design method as the most appropriate for the needs and development environment of a large nuclear or high energy physics detector. This paper discusses our specific needs and environment, our method selection criteria, and major features and components of the Shlaer-Mellor method.
Date: October 1, 1995
Creator: Kozlowski, T.; Carey, T.A. & Maguire, C.F.
Partner: UNT Libraries Government Documents Department

Polarization transfer in inelastic scattering and pionic models of the EMC effect

Description: The aim of the experiment reported was to make a precise test of the enhanced pion field model in a medium-energy scattering experiment. The quantity probed is the spin-longitudinal response function, a measure of the nuclear pion density which is used explicitly in the pion-excess models of the EMC effect. The point of reference used is deuterium. The spin-dependent response functions for heavy targets and /sup 2/H are compared using identical experimental techniques. The technique of complete polarization transfer is used to separate the spin-longitudinal and spin-transverse response in the continuum. The experiment consisted of precise determinations of the polarization transfer coefficients for 500 MeV protons inelastically scattered from Pb, Ca, and /sup 2/H. The experiment utilized longitudinal, sideways, and normal polarized beams in conjunction with final polarization analysis from the focal-plane polarimeter of the high-resolution spectrometer. Quantities constructed from these data are the longitudinal and transverse spin-flip probabilities. Calculations were performed of the ratio of longitudinal to transverse response functions and of the EMC effect with the same model. No evidence was found for collectivity in the isovector spin-longitudinal response function. 10 refs. (LEW)
Date: January 1, 1985
Creator: Carey, T.A.; Jones, K.W.; McClelland, J.B.; Moss, J.M.; Rees, L.B.; Tanaka, N. et al.
Partner: UNT Libraries Government Documents Department

Development plan for the Nucleon Physics Laboratory Facility at LAMPF

Description: A 3- to 4-year plan is described for upgrading the LAMPF Nucleon Physics Laboratory including a neutron time-of-flight facility for the (p,n) reaction, a medium-resolution spectrometer for (p,p') and n,p) studies, and a dedicated facility for atomic beam studies. Development of these facilities and relationships to other ongoing developments are detailed. The scope of the new physics programs supported by such a facility is discussed.
Date: February 1, 1986
Creator: McClelland, J.B.; Bacher, A.; Boudrie, R.L.; Carey, T.A.; Donahue, J.; Goodman, C.D. et al.
Partner: UNT Libraries Government Documents Department

Lepton-pair production in hadron-nucleus collisions

Description: The general features of lepton pair production are reviewed. 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 effects and to J//psi/ suppression in heavy ion collisions is also discussed. 73 refs., 26 figs., 2 tabs.
Date: January 1, 1988
Creator: Peng, J.C.; Alde, D.M.; Baer, H.W.; Carey, T.A.; Garvey, G.T.; Klein, A. et al.
Partner: UNT Libraries Government Documents Department

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

Preliminary results from Fermilab E789

Description: Fermilab experiment 789 studies low-multiplicity decays of neutral D and B mesons in a high-rate fixed-target environment. Preliminary results from the 1991 run are presented.
Date: January 1, 1992
Creator: Peng, J.C.; Boissevain, J.; Carey, T.A.; Jansen, D.M.; Jeppesen, R.; Kapustinsky, J.S. et al.
Partner: UNT Libraries Government Documents Department

Quasifree polarization-transfer measurements in the ( rvec p , rvec n ) reaction at 495 MeV

Description: A complete set of polarization transfer observables for quasifree scattering in the ({rvec p}, {rvec n}) reaction at 495 MeV is reported. Measurements were carried out on CD{sub 2}, natural carbon, and calcium targets at a momentum transfer of 1.72 fm{sup {minus}1} using the new Neutron Time-of-Flight facility at LAMPF. The spin-longitudinal and spin-transverse responses are extracted from the data. The ratio of these responses are compared to DWIA-RPA calculations in which the particle-hole interaction is taken to be of the form g{prime}+{pi}+{rho}. No evidence for these RPA correlations is seen in the data at this momentum transfer. 8 refs., 2 figs.
Date: January 1, 1991
Creator: McClelland, J.B.; Carey, T.A.; Rybarcyk, L.J.; Sailor, W.; Taddeucci, T.N. (Los Alamos National Lab., NM (United States)); Chen, X.Y. et al.
Partner: UNT Libraries Government Documents Department

Cross section and analyzing power for quasifree (p,n) reactions

Description: Cross sections and analyzing powers have been measured for {sup 12}C(p,n) at 494 MeV and 795 MeV and for Pb(p,n) at 795 MeV. The data span an energy loss range of at least 200 MeV, which is sufficient to clearly reveal the large peak associated with quasifree neutron knockout. The kinematics, cross section, and analyzing power for this peak are compared to the corresponding observables for free nucleon-nucleon scattering and to the observables calculated with a relativistic Fermi-gas model. 15 refs., 3 figs.
Date: January 1, 1990
Creator: Taddeucci, T.N.; Byrd, R.C.; Carey, T.A.; McClelland, J.B.; Rybarcyk, L.J.; Sailor, W.C. (Los Alamos National Lab., NM (USA)) et al.
Partner: UNT Libraries Government Documents Department

Nuclear effects in Drell-Yan and quarkonium production in proton-nucleus collisions

Description: A precise measurement of the atomic mass dependence of dimuon production induced by 800 GeV protons incident on targets of {sup 2}H, C, Ca, Fe, and W is reported. The relative Drell-Yan yield per nucleon, R = Y{sub A}/Y{sub 2{sub H}}, is sensitive to modifications of the antiquark sea in nuclei. No effect is seen for the range of target-quark momentum fraction, 0.1 < x{sub t} < 0.3. For x{sub t} < 0.1 the ratio is slightly less than unity for the heavy nuclei. These results are compared with the predictions of EMC models. A depletion of the yield per nucleon from heavy nuclei is observed for both J/{psi} and {psi}{prime} production. This depletion exhibits a strong dependence of x{sub F} and p{sub t}. Within experimental errors the depletion is the same for the J/{psi} and the {psi}{prime}. 41 refs., 6 figs.
Date: January 1, 1990
Creator: Peng, J.C.; Alde, D.M.; Baer, H.W.; Carey, T.A.; Garvey, G.T.; Klein, A. et al.
Partner: UNT Libraries Government Documents Department

Nuclear medium effects on quarks, gluons, and on vector meson production: New insights from dimuon production

Description: A precise measurement of the atomic mass dependence of dimuon continuum and vector-meson production induced by 800 GeV/c protons is reported. Approximately 700,000 muon pairs with dimuon mass M {ge} 3 GeV were recorded from targets of {sup 2}H, C, Ca, Fe, and W. The ratio of Drell-Yan dimuon yield per nucleon for nuclei versus {sup 2}H, R = Y{sub A}/Y{sub 2H}, is sensitive to modifications of the antiquark sea in nuclei. No nuclear dependence of this ratio is observed over the range of target-quark momentum fraction 0.1 < x{sub t} < 0.3. For x{sub t} < 0.1 the ratio is slightly less than unity for the heavy nuclei. These results are compared with predictions of models of the EMC effect. A depletion of the yield per nucleon from heavy nuclei is observed for the J{Psi}, {Psi}{prime}, and {Upsilon} production. This depletion exhibits strong dependence on x{sub f} and p{sub t}. 25 refs., 19 figs., 1 tab.
Date: January 1, 1990
Creator: Leitch, M.J.; Alde, D.M.; Baer, H.W.; Carey, T.A.; Garvey, G.T.; Klein, A. et al.
Partner: UNT Libraries Government Documents Department

Measurement of the LIght Quark Flavor Asymmetry in the Nucleon Sea

Description: The Drell-Yan cross section ratios, s(p+d)/s(p+p), measured in Fermilab E866, have led to the first determination of d(x)/u(x), d(x)-(x), and the integral of d(x)-u(x) for the proton over the range 0.02 &lt; x &lt; 0.345. The E866 results are compared with predictions based on parton distribution functions and various theoretical models. The relationship between the E866 results and the NMC measurements of the Gottfried integral is discussed. The agreement between the E866 results and models employing virtual mesons indicates these non-perturbative processes play an important role in the origin of the d, u asymmetry in the nucleon sea.
Date: July 23, 1998
Creator: Peng, J.C.; Awes, T.C.; Beddo, M.E.; Brooks, M.L.; Brown, C.N.; Bush, J.D. et al.
Partner: UNT Libraries Government Documents Department

Beauty and charm production from Fermilab experiment 789

Description: Experiment 789 is a fixed-target experiment at Fermilab designed to study low-multiplicity decays of charm and beauty. During the 1991 run. E789 collected {approx} 10{sup 9} events using an 800 GeV proton beam incident upon gold and beryllium targets. Analyses of these data include searches for b {yields} J/{psi}+{Chi} decays and {Alpha}- dependence measurements of neutral D meson production. Preliminary results from the 1991 run are presented in this paper.
Date: June 1, 1993
Creator: Jansen, D.M.; Boissevain, J.; Carey, T.A.; Jeppesen, R.G.; Kapustinsky, J.S.; Lane, D.W. et al.
Partner: UNT Libraries Government Documents Department

Preliminary results from Fermilab E789

Description: Fermilab experiment 789 studies low-multiplicity decays of neutral D and B mesons in a high-rate fixed-target environment. Preliminary results from the 1991 run are presented.
Date: December 1, 1992
Creator: Peng, J. C.; Boissevain, J.; Carey, T. A.; Jansen, D. M.; Jeppesen, R.; Kapustinsky, J. S. et al.
Partner: UNT Libraries Government Documents Department