arXiv:1107.0256·v1·High Energy Physics — Phenomenology
Heavy-flavor dynamics in nucleus-nucleus collisions: from RHIC to LHC
M. Monteno (1)🇮🇹 · W.M. Alberico (2 and 1)🇮🇹 · A. Beraudo (3 and 4)🇮🇹 · A. De Pace (1)🇮🇹 · A. Molinari (2 and 1)🇮🇹 · M. Nardi (2)🇮🇹 · F. Prino (2) ((1) INFN, Sezione di Torino, (2) Dipartimento di Fisica Teorica, Università di Torino, (3) Centro Studi e Ricerche E. Fermi, Rome, (4) Theory Unit, CERN)🇮🇹
Abstract
The stochastic dynamics of c and b quarks in the fireball created in nucleus-nucleus collisions at RHIC and LHC is studied employing a relativistic Langevin equation, based on a picture of multiple uncorrelated random collisions with the medium. Heavy-quark transport coefficients are evaluated within a pQCD approach, with a proper HTL resummation of medium effects for soft scatterings. The Langevin equation is embedded in a multi-step setup developed to study heavy-flavor observables in pp and AA collisions, starting from a NLO pQCD calculation of initial heavy-quark yields, complemented in the nuclear case by shadowing corrections, k_T-broadening and nuclear geometry effects. Then, only for AA collisions, the Langevin equation is solved numerically in a background medium described by relativistic hydrodynamics. Finally, the propagated heavy quarks are made hadronize and decay into electrons. Results for the nuclear modification factor R_AA of heavy-flavor hadrons and electrons from their semi-leptonic decays are provided, both for RHIC and LHC beam energies.
Comments: 4 pages, 2 figures (3 eps files); submitted for publication in the proceedings of "Quark Matter 2011", 23-28 May 2011, Annecy (France)