A new measurement of the b-bbar production cross section in 920 GeV proton-nucleus collisions is presented by the HERA-B collaboration. The b-bbar production is tagged via inclusive bottom quark decays into J/psi mesons, by exploiting the longitudinal separation of J/psi->ll decay vertices from the primary proton-nucleus interaction point. Both e+e- and mu+mu- channels are reconstructed, for a total of 83 +- 12 inclusive b->J/psi X events found. The combined analysis yields a b-bbar to prompt J/psi cross section ratio of {frac{{Deltasigma(bbbar)}}{{Deltasigma_{jpsi}}}} = 0.032pm 0.005 stat pm 0.004 sys measured in the x_f acceptance (-0.35 <x_f <0.15), extrapolated to sigma(bbbar) = 14.9 pm 2.2 stat pm 2.4 sys nb/nucleon in the total phase space.
Improved Measurement of the b-bbar Production Cross Section in 920 GeV Fixed-Target Proton-Nucleus Collisions / I. ABT; M. ADAMS; M. AGARI; H. ALBRECHT; A. ALEKSANDROV; V. AMARAL; A. AMORIM; S.J. APLIN; V. AUSHEV; Y. BAGATURIA; V. BALAGURA; M. BARGIOTTI; O. BARSUKOVA; J. BASTOS; J. BATISTA; C. BAUER; TH.S. BAUER; A. BELKOV; AR. BELKOV; I. BELOTELOV; A. BERTIN; B. BOBCHENKO; M. BOCKER; A. BOGATYREV; G. BOHM; M. BRAUER; M. BRUINSMA; M. BRUSCHI; P. BUCHHOLZ; T. BURAN; J. CARVALHO; P. CONDE; C. CRUSE; M. DAM; K.M. DANIELSEN; M. DANILOV; S. DE CASTRO; H. DEPPE; X. DONG; H.B. DREIS; V. EGORYTCHEV; K. EHRET; F. EISELE; D. EMELIYANOV; S. ESSENOV; L. FABBRI; P. FACCIOLI; M. FEUERSTACK-RAIBLE; J. FLAMMER; B. FOMINYKH; M. FUNCKE; LL. GARRIDO; A. GELLRICH; B. GIACOBBE; P. GIOVANNINI; J. GLASS; D. GOLOUBKOV; Y. GOLUBKOV; A. GOLUTVIN; I. GOLUTVIN; I. GORBOUNOV; A. GORISEK; O. GOUCHTCHINE; D.C. GOULART; S. GRADL; W. GRADL; F. GRIMALDI; YU. GUILITSKY; J.D. HANSEN; J.M. HERNANDEZ; W. HOFMANN; M. HOHLMANN; T. HOTT; W. HULSBERGEN; U. HUSEMANN; O. IGONKINA; M. ISPIRYAN; T. JAGLA; C. JIANG; H. KAPITZA; S. KARABEKYAN; N. KARPENKO; S. KELLER; J. KESSLER; F. KHASANOV; YU. KIRYUSHIN; I. KISEL; E. KLINKBY; K.T. KNOPFLE; H. KOLANOSKI; S. KORPAR; C. KRAUSS; P. KREUZER; P. KRIZAN; D. KRUCKER; S. KUPPER; T. KVARATSKHELIIA; A. LANYOV; K. LAU; B. LEWENDEL; T. LOHSE; B. LOMONOSOV; R. MANNER; R. MANKEL; S. MASCIOCCHI; I. MASSA; I. MATCHIKHILIAN; G. MEDIN; M. MEDINNIS; M. MEVIUS; A. MICHETTI; YU. MIKHAILOV; R. MIZUK; R. MURESAN; M.ZUR NEDDEN; M. NEGODAEV; M. NORENBERG; S. NOWAK; M.T. NUNEZ PARDO DE VERA; M. OUCHRIF; F. OULD-SAADA; C. PADILLA; D. PERALTA; R. PERNACK; R. PESTOTNIK; B.AA. PETERSEN; M. PICCININI; M.A. PLEIER; M. POLI; V. POPOV; D. POSE; S. PRYSTUPA; V.M. PUGATCH; Y. PYLYPCHENKO; J. PYRLIK; K. REEVES; D. REING; H. RICK; I. RIU; P. ROBMANN; I. ROSTOVTSEVA; V. RYBNIKOV; F. SANCHEZ; A. SBRIZZI; M. SCHMELLING; B. SCHMIDT; A. SCHREINER; H. SCHRODER; U. SCHWANKE; ALAN J. SCHWARTZ; ANDREAS S. SCHWARZ; B. SCHWENNINGER; B. SCHWINGENHEUER; F. SCIACCA; N. SEMPRINI-CESARI; S. SHUVALOV; L. SILVA; L. SOZUER; S. SOLUNIN; A. SOMOV; S. SOMOV; J. SPENGLER; R. SPIGHI; A. SPIRIDONOV; A. STANOVNIK; M. STARIC; C. STEGMANN; H.S. SUBRAMANIA; M. SYMALLA; I. TIKHOMIROV; M. TITOV; I. TSAKOV; U. UWER; C. VAN ELDIK; YU. VASSILIEV; M. VILLA; A. VITALE; I. VUKOTIC; H. WAHLBERG; A.H. WALENTA; M. WALTER; J.J. WANG; D. WEGENER; U. WERTHENBACH; H. WOLTERS; R. WURTH; A. WURZ; YU. ZAITSEV; M. ZAVERTYAEV; T. ZEUNER; A. ZHELEZOV; Z. ZHENG; R. ZIMMERMANN; T. ZIVKO; A. ZOCCOLI. - In: PHYSICAL REVIEW D, PARTICLES, FIELDS, GRAVITATION, AND COSMOLOGY. - ISSN 1550-7998. - STAMPA. - 73:(2006), pp. 052005-1-052005-17. [10.1103/PhysRevD.73.052005]
Improved Measurement of the b-bbar Production Cross Section in 920 GeV Fixed-Target Proton-Nucleus Collisions
BERTIN, ANTONIO;DE CASTRO, STEFANO;FABBRI, LAURA;FACCIOLI, PIETRO;GIOVANNINI, PAOLA;MASSA, IGNAZIO GIACOMO;PICCININI, MAURIZIO;SBRIZZI, ANTONIO;SEMPRINI CESARI, NICOLA;VILLA, MAURO;VITALE, ANTONIO;ZOCCOLI, ANTONIO
2006
Abstract
A new measurement of the b-bbar production cross section in 920 GeV proton-nucleus collisions is presented by the HERA-B collaboration. The b-bbar production is tagged via inclusive bottom quark decays into J/psi mesons, by exploiting the longitudinal separation of J/psi->ll decay vertices from the primary proton-nucleus interaction point. Both e+e- and mu+mu- channels are reconstructed, for a total of 83 +- 12 inclusive b->J/psi X events found. The combined analysis yields a b-bbar to prompt J/psi cross section ratio of {frac{{Deltasigma(bbbar)}}{{Deltasigma_{jpsi}}}} = 0.032pm 0.005 stat pm 0.004 sys measured in the x_f acceptance (-0.35 <x_f <0.15), extrapolated to sigma(bbbar) = 14.9 pm 2.2 stat pm 2.4 sys nb/nucleon in the total phase space.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
