Speaker
Description
The interaction of heavy quarks with the quark-gluon plasma (QGP) affects their azimuthal distribution and transverse momentum ($p_\mathrm{T}$) spectrum, hence azimuthal anisotropy coefficients ($v_{n}$) and nuclear modification factors ($R_\mathrm{AA}$) of heavy flavor hadrons are important probes of the QGP. However, a simultaneous modeling of $v_{n}$ and $R_\mathrm{AA}$ is still challenging. This talk reports the first nonprompt $\mathrm{D}^{0}$ measurements of the azimuthal anisotropy elliptic ($v_{2}$) and triangular ($v_{3}$) coefficients in large systems, using lead-lead (PbPb) collisions at $\sqrt{s_{_{\mathrm{NN}}}} = 5.02$~TeV, collected with the CMS apparatus. The measurements are performed as a function of transverse momentum, spanning 1--30 GeV/c, in three centrality classes, from central to midcentral collisions. Compared to the prompt $\mathrm{D}^{0}$ results, the nonprompt $\mathrm{D}^{0}$ $v_{2}$ flow coefficients are systematically lower and show less dependence on particle $p_\mathrm{T}$ and centrality. An indication of nonzero $v_{3}$ coefficient of the nonprompt $\mathrm{D}^{0}$ is observed. The wide $p_\mathrm{T}$ range enables the study of various flow generation mechanisms, like diffusion at low $p_\mathrm{T}$ and path-dependent parton energy loss at low and high $p_\mathrm{T}$, respectively. In addition, measurements of both prompt and nonprompt $\mathrm{D}^{0}$ mesons cross sections in PbPb and proton-proton collisions, as well as $R_\mathrm{AA}$, will be shown. The results will be compared to theoretical predictions.
| Category | Experiment |
|---|---|
| Collaboration (if applicable) | CMS |
