Particle Correlations at RHIC – Scrutiny of a Puzzle

We present calculations of two-pion and two-kaon correlation functions in relativistic heavy ion collisions from a relativistic transport model that includes explicitly a first-order phase transition from a thermalized quark-gluon plasma to a hadron gas. We compare the obtained correlation radii with recent data from RHIC. The predicted Rside radii agree with data while the Rout and Rlong radii are overestimated. We also address the impact of in-medium modifications, for example, a broadening of the ρ-meson, on the correlation radii. In particular, the longitudinal correlation radius Rlong is reduced, improving the comparison to data.