Measurement of the D-meson nuclear modification factor and elliptic flow in Pb-Pb collisions at $\sqrt{s_{\text{{NN}}}}$ = 5.02 TeV with ALICE at the LHC

TL;DR

This paper reports on measurements of D-meson production, nuclear modification factor, and elliptic flow in Pb-Pb collisions at 5.02 TeV, providing insights into charm quark interactions with the Quark-Gluon Plasma.

Contribution

It presents new measurements of D-meson R_AA and v_2 at LHC energies, including the use of Event-Shape Engineering to study charm quark coupling.

Findings

D-meson R_AA shows suppression indicating energy loss in QGP.

Elliptic flow measurements suggest charm quarks participate in collective expansion.

ESE technique reveals charm quark coupling to the medium.

Abstract

Heavy-flavour hadrons are effective probes to study the Quark-Gluon Plasma (QGP) formed in ultra-relativistic heavy-ion collisions. The ALICE Collaboration measured the D-mesons (D$^{0}$, D$^{+}$, D*$^{+}$ and D$^{+}_{\text s}$) production in Pb-Pb collisions at $\sqrt{s_{\text{{NN}}}}$ = 5.02 TeV. The in-medium energy loss can be studied by means of the nuclear modification factor ($R_{\text{AA}}$). The comparison between the D$^{+}_{\text s}$ and the non-strange D-meson $R_{\text{AA}}$ can help to study the hadronisation mechanism of the charm quark in the QGP. In semi-central collisions the measurement of the D-meson elliptic flow, $v_{2}$, at low $p_{\text{T}}$ allows to investigate the participation of the heavy quarks in the collective expansion of the system while at high $p_{\text{T}}$ it constrains the path-length dependence of the energy loss. Furthermore the Event-Shape Engineering (ESE) technique is used to measure D-meson elliptic flow in order to study the coupling of the charm quarks to the light quarks of the underlying medium.