Bottom quark energy loss and hadronization with B^+ and B^0_\mathrm{s} nuclear modification factors using pp and PbPb collisions at \sqrt{s_\mathrm{NN}} = 5.02 TeV

Abstract

The production cross sections of B and B mesons are reported in proton-proton (pp) collisions recorded by the CMS experiment at the CERN LHC with a center-of-mass energy of 5.02 TeV. The data sample corresponds to an integrated luminosity of 302 pb . The cross sections are based on measurements of the B J/ (1020) (K K ) and B J/ K decay channels. Results are presented in the transverse momentum ( ) range 7-50 GeV/ and the rapidity interval 2.4 for the B mesons. The measured -differential cross sections of B and B in pp collisions are well described by fixed-order plus next-to-leading logarithm perturbative quantum chromodynamics calculations. Using previous PbPb collision measurements at the same nucleon-nucleon center-of-mass energy, the nuclear modification factors, , of the B mesons are determined. For 10 GeV/ , both mesons are found to be suppressed in PbPb collisions (with values significantly below unity), with less suppression observed for the B mesons. In this range, the values for the B mesons are consistent with those for inclusive charged hadrons and D mesons. Below 10 GeV/ , both B and B are found to be less suppressed than either inclusive charged hadrons or D mesons, with the B value consistent with unity. The values found for the B and B are compared to theoretical calculations, providing constraints on the mechanism of bottom quark energy loss and hadronization in the quark-gluon plasma, the hot and dense matter created in ultrarelativistic heavy ion collisions.