Jet quenching in a three-dimensional hydrodynamic medium

We study the radiative energy loss of hard partons in a soft medium in the multiple soft scattering approximation. The soft medium is described by a 3D hydrodynamical model and we treat the averaging over all possible parton paths through the medium without approximation. While the nuclear suppression factor RAA does not reflect the high quality of the medium description (except in a reduced systematic uncertainty in extracting the quenching power of the medium), the hydrodynamical model also allows to study different centralities and in particular the angular variation of RAA with respect to the reaction plane, allowing for a controlled variation of the in-medium path-length. We study the angular dependence of RAA for different centralities, discuss the influence of hydrodynamical expansion and flow and comment on the comparison with preliminary data.