Study of $\pmb{R_{\rm AA}}$ and $\pmb{v_2}$ of non-strange D mesons and D-jet production in Pb-Pb collisions with ALICE

TL;DR

This paper reports on measurements of D mesons and D-jet production in Pb-Pb collisions at 5.02 TeV, providing insights into charm quark energy loss, flow, and coupling with the medium in the Quark-Gluon Plasma.

Contribution

It presents new measurements of D meson R_AA, v_2, and D-jet R_AA in Pb-Pb collisions, including the application of event-shape engineering to study charm-medium interactions.

Findings

D meson R_AA shows suppression indicating energy loss in QGP.

D meson v_2 suggests charm participation in collective flow.

D-jet R_AA provides information on in-medium modifications of jet structure.

Abstract

Heavy quarks are sensitive probes of the colour-deconfined medium formed in ultra-relativistic heavy-ion collisions, the Quark-Gluon Plasma (QGP). The ALICE Collaboration measured the production of $\rm D^0$, $\rm D^+$, and $\rm D^{*+}$ mesons in Pb-Pb collisions at $\sqrt{s_{\rm NN}}=5.02$ TeV. The properties of the in-medium energy loss are investigated via the measurement of the nuclear modification factor ($R_{\rm AA}$) of non-strange D mesons. The modification of the D-meson transverse momentum ($p_{\rm T}$) distributions inside the jet is studied via the measurement of the D-meson tagged jet $R_{\rm AA}$ in central Pb-Pb collisions. In mid-central collisions, the measurement of the D-meson elliptic flow ($v_2$) at low and intermediate $p_{\rm T}$ gives insight into the participation of the charm quark in the collective motion of the system, while at high $p_{\rm T}$ it constrains the path-length dependence of the energy loss. The coupling of the charm quark to the light quarks in the underlying medium is further investigated with the application of the event-shape engineering (ESE) technique to D-meson elliptic flow.