Speakers
Description
Within the framework of a Langevin dynamics model for heavy quarks in a hot and dense medium, combined with a sequential coalescence +fragmentation hadronization scenario which let the $D_{\rm s}$ meson produced earlier than the other hadron, we systematically calculate the Pb+Pb yield spectra of $D_s$, $D^0$, and $\Lambda^+_{c}$, the yield ratios $D_s/D^0$ and $\Lambda^+_{c}/D^0$, and their elliptic flow coefficient $v_2(p_{\rm T})$ as functions of transverse momentum $p_{\rm T}$. We find that incorporating sequential hadronization beyond hadronic-phase interactions induces an enhancement of the $v_2$ of $D^0$ and a suppression of $ v_2$ of $D_s$, resulting in anomalously suppressed $ v_2$ of $D_s$ relative to $ D^0$ in the intermediate $p_T$ region. This signature is consistent with preliminary ALICE measurements reported at the Quark Matter conference; therefore, it provides key evidence of the sequential hadronization mechanism.
