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arXiv · 1208.1643

Charm quark transport in Pb+Pb reactions at sqrt{s}_NN=2.76 TeV from a (3+1) dimensional hybrid approach

Thomas Lang·Hendrik van Hees·Jan Steinheimer·Marcus Bleicher
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Abstract

We implement a Langevin approach for the transport of charm quarks in the UrQMD (hydrodynamics + Boltzmann) hybrid model. Due to the inclusion of event-by-event fluctuations and a full (3+1) dimensional hydrodynamic evolution, this approach provides a more realistic model for the evolution of the matter produced in heavy ion collisions as compared to simple homogeneous fireball expansions usually employed. As drag and diffusion coefficients we use a resonance approach for elastic heavy-quark scattering and assume a decoupling temperature of the charm quarks from the hot medium of 130 MeV. A coalescence approach at the decoupling temperature for the hadronization of the charm quarks to D-mesons is also included. We present calculations of the nuclear modification factor R_AA as well as the elliptic flow v_2 in Pb+Pb collisions at sqrt s_NN=2.76 TeV. The comparison to ALICE measurements shows a very good agreement with our calculations.

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Thomas Lang, Hendrik van Hees, Jan Steinheimer, Marcus Bleicher. 2012-08-08. Charm quark transport in Pb+Pb reactions at sqrt{s}_NN=2.76 TeV from a (3+1) dimensional hybrid approach. https://arxiv.org/abs/1208.1643

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