Bottom production cross section from double muonic decays of b - flavoured hadrons in 920 GeV proton - nucleus collisions
نویسندگان
چکیده
The bb̄ production cross section in 920 GeV proton-nucleus fixed target collisions is measured by observing double muonic decays of b-flavoured hadrons in the kinematic region −0.3 < xF(μ) < 0.15. A total number of 76 ± 12 bb̄ events is obtained with a likelihood fit of the signal and background simulated events to the data. The resulting cross section is σbb̄ = 16.2 ± 2.5stat ± 2.8sys nb/nucleon, or, when combined with a previous HERA-B measurement of similar precision, σbb̄ = 15.4 ± 1.7stat ± 1.2 sys ± 1.9 sys nb/nucleon, which is consistent with recent NLO calculations.
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