First NA61/SHINE results on Bose-Einstein correlation function

One of the main goals of NA61/SHINE is the investigation of the phase diagram of strongly interacting matter. NA61/SHINE observes collisions of various nuclei at different energies, allowing to study the same phenomena and observables in vastly different conditions. One of the observables related to the quark-hadron transition is the Bose-Einstein momentum correlation function of identical pions, related to the space-time structure of pion emission. In this paper we report on such measurements in Be+Be collisions at an SPS beam momentum of 150A GeV/c. Our correlation functions can be statistically well described with Lévy-distributed sources, hence we also study the $m_T$ dependence of the Lévy source parameters, and discuss their possible interpretations.