  Measurement of quantumstatistical correlation functions in high energy
nuclear physics is an important tool to investigate the QCD phase diagram. It
may be used to search for the critical point, and also to understand underlying
processes such as in-medium mass modifications or partially coherent particle
production. Furthermore, the measurements of the femtoscopic correlation
functions shed light on the space-time structure of particle production.
Consequently, the precise measurements and description of the correlation
functions are essential. The shape of two-pion Bose-Einstein correlation
functions were often assumed to be Gaussian, but the recent precision of the
experiments reveals that the statistically correct assumption is the more
general L\'evy-distribution. In this paper we present the recent results of the
measurements of two-pion L\'evy-stable Bose-Einstein correlation functions in
Au+Au collisions at PHENIX
