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    Studies of B_s Production and Semileptonic Decay, and of Antideuteron Production in Upsilon Decay and Quark Fragmentation at BaBar
    (2012) Hamilton, Brian Keith; Jawahery, Abolhassan; Physics; Digital Repository at the University of Maryland; University of Maryland (College Park, Md.)
    I present a measurement of the inclusive semileptonic branching fraction of the Bs meson and Bs production rates relative to all B mesons using a data set collected with the BaBar detector at the PEP-II asymmetric energy electron-positron collider operating at center-of-mass energies above the Upsilon(4S) resonance. The quantities are extracted simultaneously using inclusive yields of phi mesons and phi mesons in coincidence with a high momentum lepton. The Bs semileptonic branching fraction is found to be B(Bs<\sub> → l ν X) = (9.5+2.5-2.0+1.1-1.9)%, where the first uncertainty is statistical and the second is systematic. Additionally, I present measurements of antideuteron production using the BaBar data collected at collision center-of-mass energies corresponding to the masses of the Upsilon(2S), Upsilon(3S), and Upsilon(4S) resonances. Measurements of specific ionization for charged tracks in the \babar\ detector are used to obtain the antideuteron production rate in decays of the Upsilon(1S), Upsilon(2S), and Upsilon(3S) resonances as well as in continuum e+e- annihilation to hadrons. The total rates observed in the data are B(Upsilon(2S) → dbar X) = (2.62 ± 0.10+0.31-0.28)× 10-5, B(Upsilon(1S) → dbar X) = (2.85 ± 0.47+0.21-0.29)× 10-5, B(Upsilon(3S) → dbar X) = (2.45 ± 0.14+0.27-0.24)× 10-5, and the cross section for antideuteron production in continuum e+e- annihilation is found to be σ(e+e- (10.58 GeV) → dbar X) = (10.49 ± 0.33+1.28-1.14) fb. No significant production in Upsilon(4S) decays is observed.
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    Precise Measurement of the Deuteron Elastic Structure Function A(Q2)
    (American Physical Society, 1999-02-15) Abbott, D.; Ahmidouch, A.; Anklin, H.; Arvieux, J.; Ball, J.; Beedoe, S.; Beise, E.J.; Bimbot, L.; Boeglin, W.; Breuer, H.; Carlini, R.; Chant, N.S.; Danagoulian, S.; Dow, K.; Ducret, J.-E.; Dunne, J.; Ent, R.; Ewell, L.; Eyraud, L.; Furget, C.; Garcon, M.; Gilman, R.; Glashausser, C.; Gueye, P.; Gustafsson, K.; Hafidi, K.; Honegger, A.; Jourdan, J.; Kox, S.; Kumbartzki, G.; Lu, L.; Lung, A.; Mack, D.; Markowitz, P.; McIntyre, J.; Meekins, D.; Merchez, F.; Mitchell, J.; Mohring, R.; Mtingwa, S.; Mrktchyan, H.; Pitz, D.; Qin, L.; Ransome, R.; Real, J.-S.; Roos, P.G.; Rutt, P.; Sawafta, R.; Stepanyan, S.; Tieulent, R.; Tomasi-Gustafsson, E.; Turchinetz, W.; Vansyoc, K.; Volmer, J.; Voutier, E.; Vulcan, W.; Williamson, C.; Wood, S.A.; Yan, C.; Zhao, J.; Zhao, W.; The Jefferson Lab t20 Collaboration
    The A(Q2) structure function in elastic electron-deuteron scattering was measured at six momentum transfers Q2 between 0.66 and 1.80(GeV/c)2 in Hall C at Jefferson Laboratory. The scattered electrons and recoil deuterons were detected in coincidence, at a fixed deuteron angle of 60.5°. These new precise measurements resolve discrepancies between older sets of data. They put significant constraints on existing models of the deuteron electromagnetic structure, and on the strength of isoscalar meson exchange currents.
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    Measurements of Deuteron Photodisintegration up to 4.0 GeV
    (American Physical Society, 1998-11-23) Bochna, C.; Terburg, B.P.; Abbott, D.J.; Ahmidouch, A.; Armstrong, C.S.; Arrington, J.; Assamagan, K.A.; Baker, O.K.; Barrow, S.P.; Beatty, D.P.; Beck, D.H.; Beedoe, S.Y.; Beise, E.J.; Belz, J.E.; Bosted, P.E.; Brash, E.J.; Breuer, H.; Cadman, R.V.; Cardman, L.; Carlini, R.D.; Cha, J.; Chant, N.S.; Collins, G.; Cothran, C.; Cummings, W.J.; Danagoulian, S.; Duncan, F.A.; Dunne, J.A.; Dutta, D.; Eden, T.; Ent, R.; Filippone, B.W.; Forest, T.A.; Fortune, H.T.; Frolov, V.V.; Gao, H.; Geesaman, D.F.; Gilman, R.; Gueye, P.L.J.; Gustafsson, K.K.; Hansen, J.-O.; Harvey, M.; Hinton, W.; Holt, R.J.; Jackson, H.E.; Keppel, C.E.; Khandaker, M.A.; Kinney, E.R.; Klein, A.; Koltenuk, D.M.; Kumbartzki, G.; Lung, A.F.; Mack, D.J.; Madey, R.; Markwoitz, P.; McFarlane, K.W.; McKeown, R.D.; Meekins, D.G.; Meziani, Z.-E.; Miller, M.A.; Mitchell, J.H.; Mkrtchyan, H.G.; Mohring, R.M.; Napolitano, J.; Nathan, A.M.; Niculescu, G.; Niculescu, I.; O'Neill, T.G.; Owen, B.R.; Pate, S.F.; Potterveld, D.H.; Price, J.W.; Rakness, G.L.; Ransome, R.; Reinhold, J.; Rutt, P.M.; Salgado, C.W.; Savage, G.; Segel, R.; Simicevic, N.; Stoler, P.; Suleiman, R.; Tang, L.; van Westrum, D.; Vulcan, W.F.; Williamson, S.; Witkowski, M.T.; Wood, S.A.; Yan, C.; Zeidman, B.
    The first measurements of the differential cross section for the d(γ,p)n reaction up to 4.0 GeV were performed at the Continuous Electron Beam Accelerator Facility (CEBAF) at Thomas Jefferson Laboratory. We report the cross sections at the proton center-of-mass angles of 36°, 52°, 69°, and 89°. These results are in reasonable agreement with previous measurements at lower energy. The 89° and 69° data show constituent-counting-rule behavior up to 4.0 GeV photon energy. The 52° and 36° data disagree with the counting-rule behavior. The quantum chromodynamics (QCD) model of nuclear reactions involving reduced amplitudes disagrees with the present data.