Workshop for young scientists with research interests focused on physics at FAIR

We implemented a Langevin approach for heavy quarks to the UrQMD hybrid model, which provides a realistic background medium for the evolution in heavy ion collisions at FAIR energies. Here we used two different sets of drag and diffusion coefficients, a T-Matrix approach and a resonance model. In case of the resonance model we also implemented different decoupling temperatures of the heavy quarks from the hot medium between $130\,$MeV and $180\,$MeV. In our calculations we evaluate the nuclear modification factor $R_{AA}$ as well as at the elliptic flow $v_2$. We find that our results depend on the decoupling temperature strongly. Additionally we investigate the influence of a coalescence versus a fragmentation approach for the heavy quark fragmentation. Predictions for FAIR energies are calculated and an outlook for RHIC and LHC energies is given.