par Aktas, Adil;Favart, Laurent 
;Janssen, Xavier ;Marage, Pierre ;Roland, Benoît ; [et al.]
Référence European Physical Journal C. Particles and Fields, 47, 3, page (597-610)
Publication Publié, 2006
;Janssen, Xavier ;Marage, Pierre ;Roland, Benoît ; [et al.]Référence European Physical Journal C. Particles and Fields, 47, 3, page (597-610)
Publication Publié, 2006
Article révisé par les pairs
| Résumé : | A measurement of charm and beauty dijet photoproduction cross sections at the ep collider HERA is presented. Events are selected with two or more jets of transverse momentum pt jet1(2) > 11(8) GeV in the central range of pseudo-rapidity -0.9 < ηjet1(2) < 1.3. The fractions of events containing charm and beauty quarks are determined using a method based on the impact parameter, in the transverse plane, of tracks to the primary vertex, as measured by the HI central vertex detector. Differential dijet cross sections for charm and beauty, and their relative contributions to the flavour inclusive dijet photoproduction cross section, are measured as a function of the transverse momentum of the leading jet, the average pseudo-rapidity of the two jets and the observable xγ obs. Taking into account the theoretical uncertainties, the charm cross sections are consistent with a QCD calculation in next-to-leading order, while the predicted cross sections for beauty production are somewhat lower than the measurement. |
