Production of $b\bar{b}$ at forward rapidity in $p$+$p$ collisions at $\sqrt{s}=510$ GeV

Abstract

The cross section of bottom quark-antiquark (b b) production in p+p collisions at √ s = 510 GeV is measured with the PHENIX detector at the Relativistic Heavy Ion Collider. The results are based on the yield of high mass, like-sign muon pairs measured within the PHENIX muon arm acceptance (1.2 < |y| < 2.2). The b b signal is extracted from like-sign dimuons by utilizing the unique properties of neutral B meson oscillation. We report a differential cross section of dσ b b→µ ± µ ± /dy = 0.16 ± 0.01 (stat) ± 0.02 (syst) ± 0.02 (global) nb for like-sign muons in the rapidity and pT ranges 1.2 < |y| < 2.2 and pT > 1 GeV/c, and dimuon mass of 5-10 GeV/c 2 . The extrapolated total cross section at this energy for b b production is 13.1 ± 0.6 (stat) ± 1.5 (syst) ± 2.7 (global) µb. The total cross section is compared to a perturbative quantum chromodynamics calculation and is consistent within uncertainties. The azimuthal opening angle between muon pairs from b b decays and their pT distributions are compared to distributions generated using ps pythia6, which includes nextto-leading order processes. The azimuthal correlations and pair pT distribution are not very well described by pythia calculations, but are still consistent within uncertainties. Flavor creation and flavor excitation subprocesses are favored over gluon splitting.