Investigating charm-quark dynamics in the QGP via the charm-hadron elliptic flow in Pb-Pb collisions with ALICE

Abstract

In these proceedings, the elliptic flow ($v_2$) measurement of prompt and non-prompt charm hadrons - originating respectively from the fragmentation of a charm quark and from the decay of hadrons with beauty-quark content - in Pb-Pb collisions at $\sqrt{s_{\mathrm{NN}}}=5.36\text{TeV}$, using the latest data collected during LHC Run 3 by the ALICE detector, is presented. The analysis is performed at midrapidity ($|y|<0.8$), and hadronic decay channels are used to reconstruct the signal candidates. The $v_2$ coefficient is measured via the Scalar Product (SP) technique. The prompt $v_2$ in semicentral collisions is reported for the $D^0$, $D^{+}$, $D_s^{+}$ mesons and, for the first time, for the ${\Lambda }_c^{+}$ baryon. These results achieve unprecedented precision and low-$p_{\mathrm{T}}$ reach for the D mesons and highlight the first observation of the splitting of baryon and meson elliptic flow at intermediate $p_{\mathrm{T}}$ in the charm sector. The $v_2$ is also measured for prompt $D^0$, $D^{+}$ and $D_s^{+}$ in peripheral collisions, offering new insights into the features of the fireball generated in ultrarelativistic heavy-ion collisions. Lower $v_2$ values are observed for non-prompt $D^0$ and ${\Lambda }_c^{+}$ hadrons in semicentral collisions, as expected from the larger beauty-quark mass.

9 pages, 5 figures, Proceedings of the 2025 European Physical Society Conference on High Energy Physics (7/7/2025-11/7/2025), EPS-HEP2025, Marseille, France