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Measurement of inclusive(D(s)(±)) photoproduction at HERA ZEUS collaboration

Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics 481:2-4 (2000) 213-227

Authors:

J Breitweg, S Chekanov, M Derrick, D Krakauer, S Magill, B Musgrave, A Pellegrino, J Repond, R Stanek, R Yoshida, MCK Mattingly, G Abbiendi, F Anselmo, P Antonioli, G Bari, M Basile, L Bellagamba, D Boscherini, A Bruni, G Bruni, G Cara Romeo, G Castellini, L Cifarelli, F Cindolo, A Contin, N Coppola, M Corradi, S de Pasquale, P Giusti, G Iacobucci, G Laurenti, G Levi, A Margotti, T Massam, R Nania, F Palmonari, A Pesci, A Polini, G Sartorelli, Y Zamora Garcia, A Zichichi, C Amelung, A Bornheim, I Brock, K Coböken, J Crittenden, R Deffner, H Hartmann, K Heinloth, E Hilger, P Irrgang, HP Jakob, A Kappes, UF Katz, R Kerger, E Paul, H Schnurbusch, A Stifutkin, J Tandler, KC Voss, A Weber, H Wieber, DS Bailey, O Barret, NH Brook, B Foster, GP Heath, HF Heath, JD McFall, D Piccioni, E Rodrigues, J Scott, RJ Tapper, M Capua, A Mastroberardino, M Schioppa, G Susinno, HY Jeoung, JY Kim, JH Lee, IT Lim, KJ Ma, MY Pac, A Caldwell, W Liu, X Liu, B Mellado, S Paganis, S Sampson, WB Schmidke, F Sciulli, J Chwastowski, A Eskreys, J Figiel, K Klimek, K Olkiewicz, K Piotrzkowski, MB Przybycień, P Stopa, L Zawiejski

Abstract:

The first measurement of inclusive D(s)(±) photoproduction at HERA has been performed with the ZEUS detector for photon-proton centre-of-mass energies 130 < W < 280GeV. The measured cross section for 3 < p (is perpendicular to)/(D(s)) < 12GeV and |η(D(s))| < 1.5 is σ(ep → D(s)X) = 3.79 ± 0.59(stat.) -0.46/+0.26 (syst.) ± 0.94(br.)nb, where the last error arises from the uncertainty in the D(s)(±) decay branching ratio. The measurements are compared with inclusive D*(±) photoproduction cross sections in the same kinematic region and with QCD calculations. The D(s)(±) cross sections lie above a fixed-order next-to-leading order calculation and agree better with a tree-level O(αα(s)/3) calculation that was tuned to describe the ZEUS D*(±) cross sections. The ratio of D(s)(±) to D*(±) cross sections is 0.41 ± 0.07 (stat.) -0.05/+0.03 (syst.) ± 0.10(br.). From this ratio, the strangeness-suppression factor in charm photoproduction, within the LUND string fragmentation model, has been calculated to be γ(s) = 0.27 ± 0.05 ± 0.07(br.). The cross-section ratio and γ(s) are in good agreement with those obtained in charm production in e+e- annihilation. (C) 2000 Elsevier Science B.V.
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Irradiation studies of multimode optical fibres for use in ATLAS front-end links

Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment 446:3 (2000) 426-434

Authors:

G Mahout, M Pearce, ML Andrieux, CB Arvidsson, DG Charlton, B Dinkespiler, JD Dowell, L Gallin-Martel, RJ Homer, P Jovanovic, IR Kenyon, G Kuyt, J Lundquist, I Mandič, O Martin, HR Shaylor, R Stroynowski, J Troska, RL Wastie, AR Weidberg, JA Wilson, J Ye

Abstract:

The radiation tolerance of three multimode optical fibres has been investigated to establish their suitability for the use in the front-end data links of the ATLAS experiment. Both gamma and neutron irradiation studies are reported. A step-index fibre with a pure silica core showed an induced attenuation of approximately 0.05 dB/m at 330 kGy(Si) and 1×1015 n(1 MeV Si)/cm2 and is suitable for use with the inner detector links which operate at 40-80 Mb/s. A graded-index fibre with a predominantly germanium-doped core exhibits an induced attenuation of approximately 0.1 dB/m at 800 Gy(Si) and 2×1013 n(1 MeV Si)/cm2 and is suitable for the calorimeter links which operate at 1.6 Gb/s. Measurements of the dose rate dependence of the induced attenuation indicate that the attenuation in ATLAS will be lower.
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Measurement of the Proton Structure Function F_2 at Very Low Q^2 at HERA

ArXiv hep-ex/0005018 (2000)
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Measurement of the differential dijet mass cross section in pp¯ collisions at s=1.8 TeV

Physical Review D American Physical Society (APS) 61:9 (2000) 091101

Authors:

T Affolder, H Akimoto, A Akopian, MG Albrow, P Amaral, SR Amendolia, D Amidei, K Anikeev, J Antos, G Apollinari, T Arisawa, T Asakawa, W Ashmanskas, M Atac, F Azfar, P Azzi-Bacchetta, N Bacchetta, MW Bailey, S Bailey, P de Barbaro, A Barbaro-Galtieri, VE Barnes, BA Barnett, M Barone, G Bauer, F Bedeschi, S Belforte, G Bellettini, J Bellinger, D Benjamin, J Bensinger, A Beretvas, JP Berge, J Berryhill, S Bertolucci, B Bevensee, A Bhatti, C Bigongiari, M Binkley, D Bisello, RE Blair, C Blocker, K Bloom, B Blumenfeld, SR Blusk, A Bocci, A Bodek, W Bokhari, G Bolla, Y Bonushkin, D Bortoletto, J Boudreau, A Brandl, S van den Brink, C Bromberg, M Brozovic, N Bruner, E Buckley-Geer, J Budagov, HS Budd, K Burkett, G Busetto, A Byon-Wagner, KL Byrum, M Campbell, A Caner, W Carithers, J Carlson, D Carlsmith, J Cassada, A Castro, D Cauz, A Cerri, AW Chan, PS Chang, PT Chang, J Chapman, C Chen, YC Chen, MT Cheng, M Chertok, G Chiarelli, I Chirikov-Zorin, G Chlachidze, F Chlebana, L Christofek, ML Chu, S Cihangir, CI Ciobanu, AG Clark, A Connolly, J Conway, J Cooper, M Cordelli, D Costanzo, J Cranshaw, D Cronin-Hennessy, R Cropp, R Culbertson, D Dagenhart, F DeJongh, S Dell’Agnello, M Dell’Orso, R Demina, L Demortier, M Deninno, PF Derwent, T Devlin, JR Dittmann, S Donati, J Done, T Dorigo, N Eddy, K Einsweiler, JE Elias, E Engels, W Erdmann, D Errede, S Errede, Q Fan, RG Feild, C Ferretti, I Fiori, B Flaugher, GW Foster, M Franklin, J Freeman, J Friedman, Y Fukui, S Galeotti, M Gallinaro, T Gao, M Garcia-Sciveres, AF Garfinkel, P Gatti, C Gay, S Geer, DW Gerdes, P Giannetti, P Giromini, V Glagolev, M Gold, J Goldstein, A Gordon, AT Goshaw, Y Gotra, K Goulianos, H Grassmann, C Green, L Groer, C Grosso-Pilcher, M Guenther, G Guillian, J Guimaraes da Costa, RS Guo, C Haber, E Hafen, SR Hahn, C Hall, T Handa, R Handler, W Hao, F Happacher, K Hara, AD Hardman, RM Harris, F Hartmann, K Hatakeyama, J Hauser, J Heinrich, A Heiss, M Herndon, B Hinrichsen, KD Hoffman, C Holck, R Hollebeek, L Holloway, R Hughes, J Huston, J Huth, H Ikeda, J Incandela, G Introzzi, J Iwai, Y Iwata, E James, H Jensen, M Jones, U Joshi, H Kambara, T Kamon, T Kaneko, K Karr, H Kasha, Y Kato, TA Keaffaber, K Kelley, M Kelly, RD Kennedy, R Kephart, D Khazins, T Kikuchi, M Kirk, BJ Kim, HS Kim, MJ Kim, SH Kim, YK Kim, L Kirsch, S Klimenko, P Koehn, A Köngeter, K Kondo, J Konigsberg, K Kordas, A Korn, A Korytov, E Kovacs, J Kroll, M Kruse, SE Kuhlmann, K Kurino, T Kuwabara, AT Laasanen, N Lai, S Lami, S Lammel, JI Lamoureux, M Lancaster, G Latino, T LeCompte, AM Lee, S Leone, JD Lewis, M Lindgren, TM Liss, JB Liu, YC Liu, N Lockyer, J Loken, M Loreti, D Lucchesi, P Lukens, S Lusin, L Lyons, J Lys, R Madrak, K Maeshima, P Maksimovic, L Malferrari, M Mangano, M Mariotti, G Martignon, A Martin, JAJ Matthews, J Mayer, P Mazzanti, KS McFarland, P McIntyre, E McKigney, M Menguzzato, A Menzione, C Mesropian, T Miao, R Miller, JS Miller, H Minato, S Miscetti, M Mishina, G Mitselmakher, N Moggi, E Moore, R Moore, Y Morita, A Mukherjee, T Muller, A Munar, P Murat, S Murgia, M Musy, J Nachtman, S Nahn, H Nakada, T Nakaya, I Nakano, C Nelson, D Neuberger, C Newman-Holmes, C-YP Ngan, P Nicolaidi, H Niu, L Nodulman, A Nomerotski, SH Oh, T Ohmoto, T Ohsugi, R Oishi, T Okusawa, J Olsen, C Pagliarone, F Palmonari, R Paoletti, V Papadimitriou, SP Pappas, D Partos, J Patrick, G Pauletta, M Paulini, C Paus, L Pescara, TJ Phillips, G Piacentino, KT Pitts, R Plunkett, A Pompos, L Pondrom, G Pope, M Popovic, F Prokoshin, J Proudfoot, F Ptohos, G Punzi, K Ragan, A Rakitine, D Reher, A Reichold, W Riegler, A Ribon, F Rimondi, L Ristori, WJ Robertson, A Robinson, T Rodrigo, S Rolli, L Rosenson, R Roser, R Rossin, WK Sakumoto, D Saltzberg, A Sansoni, L Santi, H Sato, P Savard, P Schlabach, EE Schmidt, MP Schmidt, M Schmitt, L Scodellaro, A Scott, A Scribano, S Segler, S Seidel, Y Seiya, A Semenov, F Semeria, T Shah, MD Shapiro, PF Shepard, T Shibayama, M Shimojima, M Shochet, J Siegrist, G Signorelli, A Sill, P Sinervo, P Singh, AJ Slaughter, K Sliwa, C Smith, FD Snider, A Solodsky, J Spalding, T Speer, P Sphicas, F Spinella, M Spiropulu, L Spiegel, L Stanco, J Steele, A Stefanini, J Strologas, F Strumia, D Stuart, K Sumorok, T Suzuki, T Takano, R Takashima, K Takikawa, P Tamburello, M Tanaka, B Tannenbaum, W Taylor, M Tecchio, PK Teng, K Terashi, S Tether, D Theriot, R Thurman-Keup, P Tipton, S Tkaczyk, K Tollefson, A Tollestrup, H Toyoda, W Trischuk, JF de Troconiz, J Tseng, N Turini, F Ukegawa, J Valls, S Vejcik, G Velev, R Vidal, R Vilar, I Volobouev, D Vucinic, RG Wagner, RL Wagner, J Wahl, NB Wallace, AM Walsh, C Wang, CH Wang, MJ Wang, T Watanabe, D Waters, T Watts, R Webb, H Wenzel, WC Wester, AB Wicklund, E Wicklund, HH Williams, P Wilson, BL Winer, D Winn, S Wolbers, D Wolinski, J Wolinski, S Wolinski, S Worm, X Wu, J Wyss, A Yagil, W Yao, GP Yeh, P Yeh, J Yoh, C Yosef, T Yoshida, I Yu, S Yu, A Zanetti, F Zetti, S Zucchelli
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Measuring CP violation and B0s-B̄0s mixing using B0s → J/ψφ with φ → K+K-, J/ψ → μ+μ-

Journal of Physics G Nuclear and Particle Physics 26:5 (2000) 741-743

Authors:

F Azfar, T Huffman, L Lyons, A Reichold, D Waters

Abstract:

We present a preliminary study of a new technique for measuring B0s mixing and CP violation using the decay B0s → J/ψφ, φ K+K-, J/ψ → μ+μ-. This technique utilizes the unequal lifetimes of the B0s CP even and odd eigenstates, and an angular variable decomposition of the CP content of the final state. This study is based on CDF Run-I observations and Run-II projections, and predicts that the B0s mixing parameter cursive Greek chis can be measured with high accuracy in untagged samples if this approach is adopted. A large CP asymmetry may also be possible to measure. The accuracy of this method is shown to increase for higher values of cursive Greek chis as the lifetime splitting of the CP eigenstates increases. The measurement of cursive Greek chis does not depend on tagging, whereas the observation of a CP-violating asymmetry does.
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