Speaker
Description
Heavy quarks (charm and beauty) are a powerful tool to study the properties of the Quark-Gluon Plasma (QGP), the hot and dense medium formed in high-energy heavy-ion collisions. Due to their large masses, heavy quarks are produced in hard partonic scattering processes in the initial stages of the collision. Therefore, they experience the whole system evolution interacting with the medium constituents. The measurement of heavy-flavour production can give us different information depending on the type of collision. In p-Pb collisions, it makes it possible to study cold nuclear matter effects, such as shadowing, $k_{\rm T}$ broadening and initial-state energy loss, as well as possible geometrical and collective effects in high-multiplicity events. In Pb-Pb collisions, it allows us to test parton energy-loss models and to investigate the participation of heavy quarks in the collective expansion of the system.
In ALICE, open charm production is measured through the full reconstruction of D-meson hadronic decays at mid-rapidity.
In this talk, the ALICE results on the production of prompt D mesons in p-Pb and Pb-Pb collisions will be presented, focusing on the recent results from LHC Run II data.
The main physical observables measured are: the nuclear modification factor ($R_{\rm AA}$), which compares the D-meson yields in p-Pb (Pb-Pb) collisions to the binary scaled D-meson yields in pp collisions, and the elliptic flow ($v_2$), the second Fourier coefficient of the D-meson azimuthal distribution. We will report the D-meson cross section and nuclear modification factor in p-Pb collisions as a function of the event multiplicity. In addition, the $R_{\rm AA}$ and $v_2$ in different Pb-Pb collision centralities will be discussed. The results will be also compared with theoretical predictions.
| Topic: | Topic: Heavy Ion Collisions and Critical Phenomena |
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