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 L´evy 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 GribovRegge 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.
EPOS is a generator which allows one to simulate various types of collisions of divers systems with different initial parameters. It considers the parton-based Gribov-Regge theory. So far the EPOS model has been used to describe higher collision energies obtained with RHIC or LHCy data. On the other hand, there is another program under investigation: Beam Energy Scan conducted at Brookhaven National Laboratory. The beams of gold ions are collided at energies such as √sNN - 7:7; 11:5; 19:6; 27; 39, and 62.4 GeV in order to collect and analyze data needed in examination of QGP Phase Diagram. The EPOS model could become a useful tool in such studies. Simulated with EPOS data will be verified using elliptic flow analyses and two-particles femtoscopic correlations, which allow one to measure the size of sources determined by newly created particle.