Measurement of the b anti-b production cross-section in 920-GeV fixed target proton nucleus collisions.

H. WAHLBERG Y HERA-B COLLABORATION

EUROPEAN PHYSICAL JOURNAL C - PARTICLES AND FIELDS

SPRINGER

Año: 2003 vol. 26 p. 345 - 355

1434-6044

Using the HERA-B detector, the b-bbar production cross section has been measured in 920 GeV proton collisions on carbon and titanium targets. The b-bbar production was tagged via inclusive bottom quark decays into J/psi, by exploiting the longitudinal separation of J/psi->ll decay vertices from the primary proton-nucleus interaction. Both $e^+e^-$ and $mu^+mu^-$ channels have been reconstructed and the combined analysis yields the cross section $sigma(b ar b) = 32 ^{+14}_{-12} (stat) ^{+6}_{-7} (sys) nb/nucleon$.