Measurements of azimuthal anisotropy of nonprompt D$^0$ mesons in PbPb collisions at $\sqrt{s_\mathrm{NN}}$ = 5.02 TeV

The collaboration
CMS-HIN-21-003, 2022.

Abstract (data abstract)
The first heavy ion collisions measurements of azimuthal anisotropy elliptic ($v_2$) and triangular ($v_3$) Fourier coefficients of $\mathrm{D}^0$ mesons produced in b hadron decays are presented using PbPb collisions at $\sqrt{s_{_{\mathrm{NN}}}}=5.02~\mathrm{TeV}$. The obtained results are directly compared with previously published charm quark anisotropy measured in the same final state. The data were collected with the CMS detector in 2018 with an integrated luminosity of $0.58~\mathrm{nb}^{-1}$. Azimuthal anisotropy is sensitive to the interactions of quarks with the hot and dense medium created in heavy ion collisions. Comparing results for charm quarks, measured by a $\mathrm{D}^0$ meson, to those for the heavier bottom quarks can assist in understanding the mass dependence of these interactions. The results show lower magnitudes of $v_2$ and $v_3$ and weaker dependences on the meson transverse momentum and collision centrality than those found for prompt $\mathrm{D}^0$ mesons. The $v_3$ coefficient of $\mathrm{D}^0$ mesons from b hadron decays is found to be nonzero. The results are compared to various theoretical calculations.