Speaker
Description
Heavy quarks, i.e. charm and beauty, are formed on a shorter time scale with respect to the strongly-interacting Quark-Gluon Plasma (QGP) produced in high-energy heavy-ion collisions. Therefore, they are sensitive probes to study the mechanisms of parton energy loss, hadronisation in the hot and dense medium, the medium evolution and its transport coefficients. The heavy-flavour nuclear modification factor ($R_{\rm AA}$) and the elliptic flow ($v_2$) are two of the main experimental observables that allow us to investigate the interaction strength of heavy quarks with the constituents of the expanding medium. The comparison of the $R_{\rm AA}$ of charm, beauty and light-flavour hadrons provides information about the colour-charge and parton-mass dependence of parton energy loss. At low $p_{\rm T}$ the $v_2$ is expected to give insights into the degree of thermalisation of heavy quarks in the deconfined medium, and at high $p_{\rm T}$ it carries information on the path-length dependence of in-medium parton energy loss.
In this talk, measurements of $R_{\rm AA}$ and $v_2$ of open heavy-flavour hadrons via semi-leptonic decays to electrons at mid-rapidity and muons at forward rapidity in Pb-Pb collisions at LHC energies will be discussed. The progress on the analysis of the production and anisotropy of electrons from beauty-hadron decays will also be discussed. In addition, the $R_{\rm AA}$ of heavy-flavour hadron decay leptons in Xe-Xe collisions will be presented, along with the prospects for measuring the total charm cross section in this collision system. Comparisons with model calculations including the interaction of heavy quarks with the hot, dense, and deconfined medium will be also shown.
| Content type | Experiment |
|---|---|
| Collaboration | ALICE |
| Centralised submission by Collaboration | Presenter name already specified |
