  By measuring the momentum correlations of pions created in heavy-ion
collisions we can gain information about the space-time geometry of the
particle emitting source. Recent experimental results from multiple different
collaborations demonstrated that to properly describe the shape of the measured
correlation functions, one needs to go beyond the Gaussian approximation. Some
studies suggest that the Levy distribution could provide a good description of
the source. While there are already many experimental results, there is very
little input from the phenomenology side in explanation of the observed
non-Gaussian source shapes. The EPOS model is a sophisticated hybrid model
where the evolution of the newly-created system is governed by Parton-Based
Gribov-Regge theory. It has already proved to be successful in describing many
different experimental observations for the systems characterized by baryon
chemical potential close to zero, but so far the source shape has not been
explored in detail. In this paper we discuss studies of the pion emitting
source based on the theoretical approach of the EPOS model.
