Measurement of open beauty production in photoproduction at HERA

Breitweg, J Chekanov, S Derrick, M Krakauer, D Magill, S Musgrave, B Pellegrino, A Repond, J Stanek, R Yoshida, R Mattingly, MCK Antonioli, P Bari, G Basile, M Bellagamba, L Boscherini, D Bruni, A Bruni, G Romeo, GC Cifarelli, L Cindolo, F Contin, A Corradi, M De Pasquale, S Giusti, P Iacobucci, G Levi, G Margotti, A Massam, T Nania, R Palmonari, F Pesci, A Sartorelli, G Zichichi, A Aghuzumtsyan, G Amelung, C Brock, I Coboken, K Goers, S Hartmann, H Heinloth, K Hilger, E Irrgang, P Jakob, HP Kappes, A Katz, UF Kerger, R Kind, O Paul, E Rautenberg, J Schnurbusch, H Stifutkin, A Tandler, J Voss, KC Weber, A Wieber, H Bailey, DS Barret, O Brook, NH Cole, JE Foster, B Heath, GP Heath, HF Robins, S Rodrigues, E Scott, J Tapper, RJ Capua, M Mastroberardino, A Schioppa, M Susinno, G Jeoung, HY Kim, JY Lee, JH Lim, IT Ma, KJ Pac, MY Caldwell, A Liu, W Liu, X Mellado, B Paganis, S Sampson, S Schmidke, WB Sciulli, F Chwastowski, J Eskreys, A Figiel, J Klimek, K Olkiewicz, K Piotrzkowski, K Przybycien, MB Stopa, P Zawiejski, L Bednarek, B Jelen, K Kisielewska, D Kowal, AM Kowalski, T Przybycien, M Rulikowska-Zarebska, E Suszycki, L Szuba, D Kotanski, A Bauerdick, LAT Behrens, U Bienlein, JK Borras, K Chiochia, V Crittenden, J Dannheim, D Desler, K Drews, G Fox-Murphy, A Fricke, U Goebel, F Gottlicher, P Graciani, R Haas, T Hain, W Hartner, GF Hebbel, K Hillert, S Koch, W Kotz, U Kowalski, H Labes, H Lohr, B Mankel, R Martens, J Martinez, M Milite, M Moritz, M Notz, D Petrucci, MC Polini, A Rohde, M Savin, AA Schneekloth, U Selonke, F Sievers, M Stonjek, S Wolf, G Wollmer, U Youngman, C Zeuner, W Coldewey, C Viani, ALD Meyer, A Schlenstedt, S Straub, PB Barbagli, G Gallo, E Parenti, A Pelfer, PG Bamberger, A Benen, A Coppola, N Eisenhardt, S Markun, P Raach, H Wolfle, S Bussey, PJ Bell, M Doyle, AT Glasman, C Lee, SW Lupi, A Macdonald, N McCance, GJ Saxon, DH Sinclair, LE Skillicorn, IO Waugh, R Bodman, B Gendner, N Holm, U Salehi, H Wick, K Yildirim, A Carli, T Garfagnini, A Geiser, A Gialas, I Kcira, D Klanner, R Lohrmann, E Goncalo, R Long, KR Miller, DB Tapper, AD Walker, R Cloth, P Filges, D Ishii, T Kuze, M Nagano, K Tokushuku, K Yamada, S Yamazaki, Y Barakbaev, AN Boos, EG Pokrovskiy, NS Zhautykov, BO Ahn, SH Lee, SB Park, SK Lim, H Son, D Barreiro, F Garcia, G Gonzalez, O Labarga, L del Peso, J Redondo, I Terron, J Vazquez, M Barbi, M Corriveau, F Padhi, S Stairs, DG Wing, M Tsurugai, T Antonov, A Bashkirov, V Danilov, M Dolgoshein, BA Gladkov, D Sosnovtsev, V Suchkov, S Dementiev, RK Ermolov, PF Golubkov, YA Katkov, II Khein, LA Korotkova, NA Korzhavina, IA Kuzmin, VA Lukina, OY Proskuryakov, AS Shcheglova, LM Solomin, AN Vlasov, NN Zotkin, SA Bokel, C Botje, M Brummer, N Engelen, J Grijpink, S Koffeman, E Kooijman, P Schagen, S van Sighem, A Tassi, E Tiecke, H Tuning, N Velthuis, JJ Vossebeld, J Wiggers, L de Wolf, E Bylsma, B Durkin, LS Gilmore, J Ginsburg, CM Kim, CL Ling, TY Boogert, S Cooper-Sarkar, AM Devenish, RCE Grosse-Knetter, J Matsushita, T Ruske, O Sutton, MR Walczak, R Bertolin, A Brugnera, R Carlin, R Dal Corso, F Dusini, S Limentani, S Longhin, A Posocco, M Stanco, L Turcato, M Adamczyk, L Iannotti, L Oh, BY Okrasinski, JR Saull, PRB Toothacker, WS Whitmore, JJ Iga, Y D'Agostini, G Marini, G Nigro, A Cormack, C Hart, JC McCubbin, NA Shah, TP Epperson, D Heusch, C Sadrozinski, HFW Seiden, A Wichmann, R Williams, DC Park, IH Pavel, N Abramowicz, H Dagan, S Gabareen, A Kananov, S Kreisel, A Levy, A Abe, T Fusayasu, T Kohno, T Umemori, K Yamashita, T Hamatsu, R Hirose, T Inuzuka, M Kitamura, S Matsuzawa, K Nishimura, T Arneodo, M Cartiglia, N Cirio, R Costa, M Ferrero, MI Maselli, S Monaco, V Peroni, C Ruspa, M Sacchi, R Solano, A Staiano, A Bailey, DC Fagerstroem, CP Galea, R Koop, T Levman, GM Martin, JF Mirea, A Sabetfakhri, A Butterworth, JM Gwenlan, C Hayes, ME Heaphy, EA Jones, TW Lane, JB West, BJ Ciborowski, J Ciesielski, R Grzelak, G Nowak, RJ Pawlak, JM Pawlak, R Smalska, B Tymieniecka, T Wroblewski, AK Zakrzewski, JA Zarnecki, AF Adamus, M Gadaj, T Deppe, O Eisenberg, Y Gladilin, LK Hochman, D Karshon, U Badgett, WF Chapin, D Cross, R Foudas, C Mattingly, S Reeder, DD Smith, WH Vaiciulis, A Wildschek, T Wodarczyk, M Deshpande, A Dhawan, S Hughes, VW Bhadra, S Catterall, CD Frisken, WR Hall-Wilton, R Khakzad, M Menary, S

J. Breitweg et al., Measurement of open beauty production in photoproduction at HERA, EUR PHY J C, 18(4), 2001, pp. 625-637

54

INGLESE

Article

Physics

EUROPEAN PHYSICAL JOURNAL C

1434-6044 → ACNP

18

4

2001

625 - 637

ISI

1434-6044(200101)18:4<625:MOOBPI>2.0.ZU;2-T

The production and semi-leptonic decay of heavy quarks have been studied in the photoproduction process e(+)p -> e(+) + dijet + e(-) + X with the ZEUS detector st HERA using an integrated luminosity of 38.5 pb(-1). Events wit h photon-proton centre-of-mass energies, W-gammap, between 134 and 289 GeV and a photon virtuality, Q(2), less than 1 GeV2 were selected requiring at least two jets of transverse energy E-T(jet(2)) > 7(6) GeV and an electron in the final state. The electrons were identified by employing the ionisati on energy loss measurement. The contribution of beauty quarks was determine d using the transverse momentum of the electron relative to the axis of the closest jet, p(T)(rol). The data, after background subtraction, were fit w ith a Monte Carlo simulation including beauty and charm decays, The measure d beauty cross section was extrapolated to the parton level with the b quar k restricted to the region of tranverse momentum p(T)(b) > p(T)(min) = 5 Ge V and pseudorapidity \ eta (b)\ < 2 The extrapolated cross section is 1.6 /- 0.4 (stat.)(-0.5)(+0.3), (syst.)(-0.4)(+0.2) (ext.) nb. The result is co mpared to a perturbative QCD calculation performed to next-to-leading order .