Femtoscopy analysis in small systems at NA61/SHINE

Abstract

Recent measurements of femtoscopic correlations at NA61/SHINE unravel that the shape of the particle emitting source is not Gaussian. The measurements are based on L\'evy-stable symmetric sources, and we discuss the average pair transverse mass dependence of the source parameters. One of the parameters, the L\'evy exponent $\alpha$, is of particular importance. It describes the shape of the source, which, in the vicinity of the critical point of the QCD phase diagram, may be related to the critical exponent $\eta$. Its measurement hence may contribute to the search for and characterization of the critical point of the phase diagram.