LAUSR

The differential production cross sections of $B^{\pm}$ mesons are measured via the exclusive decay channels $B^{\pm} \to J\psi K^{\pm} \to \mu^+\mu_- K^{\pm}$ as a function of transverse momentum in $pp$ and PbPb collisions at a center-of-mass energy $\sqrt{s_{NN}}$ = 5.02 TeV per nucleon pair with the CMS detector at the LHC. The $pp(PbPb)$ dataset used for this analysis corresponds to an integrated luminosity of 28.0 fb$^{−1}$ (351 $\mu b^{-1}$). The measurement is performed in the $B^{\pm}$ meson transverse momentum range of 7 to 50 $GeV /c$, in the rapidity interval $\vert y \vert$ <2.4. In this kinematic range, a strong suppression of the production cross section by about a factor of two is observed in the PbPb system in comparison to the expectation from $pp$ reference data. These results are compared to theoretical calculations incorporating beauty quark diffusion and energy loss in a quark-gluon plasma.