Investigation of the femtoscopic correlation functions in heavy ion reactions is an important tool to access to the space-time structure of the hadron production of the sQGP. The description of the measured correlation functions is often assumed to be Gaussian, but a detailed analysis reveals that the statistically correct assumption is a generalized Gaussian, the so-called Lévy distribution. One of the resulting source parameters, the Lévy stability parameter alpha, describing the shape of the source, is related to one of the critical exponents (the so-called correlation exponent eta), and thus may shed light on the location of the critical endpoint on the phase diagram. In this talk we present the status of the measurement of two-pion Bose-Einstein correlation functions in Au+Au collisions at PHENIX. We investigate the collision energy, centrality and transverse mass dependence of the Lévy parameters of the correlation functions: the strength or the intercept parameter lambda, the Lévy scale parameter R and the Lévy stability parameter alpha.
|List of tracks||Femtoscopy at RHIC and LHC: links to QGP physics|