中国物理学会高能物理分会第十三届全国粒子物理学术会议（2021）

Heavy quarks are an excellent probe to study the strongly interacting quark-gluon plasma (QGP) created in high-energy heavy-ion collisions. They are mainly produced via initial hard partonic scattering processes and thus experience the entire evolution of the QGP medium. For $J/\psi$, a bound state of charm quarks, a strong suppression was seen in central collisions at the SPS and RHIC energies whereas at LHC energies (re-)generation is found to be the dominant production mechanism at low transverse momentum ($p_{\rm T}$) and in central collisions. As both suppression and (re-)generation are caused by the presence of a colored medium, $J/\psi$ yields are indeed a sensitive probe of deconfinement of the charm quarks in the QGP. In this talk, the nuclear modification factor $R_{AA}$ of inclusive $J/\psi$ will be shown as a function of centrality and $p_{\rm T}$, and the elliptic flow coefficient $v_{2}$ $p_{\rm T}$ dependent in Pb-Pb collisions at $\sqrt{s_{NN}}$ = 5.02 TeV. This analysis performed on data which were taken in 2018 by ALICE will be presented. The sample provides significantly increased statistics with the central and semi-central triggers compared to the previous runs, in a kinematic region down to $p_{\rm T}$ =0 at midrapidity. The measurement will be compared with the previous ALICE results and several model calculations. The status of the analysis aiming at disentangling prompt and non-prompt $J/\psi$ will also be discussed.