Heavy flavor production in heavy ion collisions with CMS

The measurement of heavy flavor production is a powerful tool to study the properties of the high-density QCD medium created in heavy-ion collisions as heavy quarks are sensitive to the transport properties of the medium and may interact with the matter differently than light quarks. Heavy flavor jets, non-prompt $J/\psi$ (J/$\psi$ from B-hadron decay) and fully reconstructed B mesons have been studied in PbPb collisions at 2.76 TeV and pPb collisions at 5.02 TeV with CMS. Recently, the nuclear modification factor of prompt ${D}^{\rm 0}$ mesons has been measured in PbPb collisions at 2.76 TeV with CMS as a function of both transverse momentum and collision centrality. These studies show that prompt ${D}^{\rm 0}$ production is suppressed in semi-central to central PbPb collisions and the suppression is smaller at high \pt. A comparison with the $R_{AA}$ of charged particle and non-prompt $J/\psi$ hints a hierarchy of suppression as a function of flavor.