Centrality dependent L\'evy-stable two-pion Bose-Einstein correlations at the PHENIX experiment

TL;DR

This paper analyzes two-pion Bose-Einstein correlations in heavy ion collisions, using Lévystable distributions to explore the space-time structure of particle production and potential signals of QCD phase transitions.

Contribution

It presents the first centrality-dependent measurements of Lévystable two-pion correlations in Au+Au collisions at PHENIX, offering insights into the QGP and critical endpoint.

Findings

Lévystable fits better describe correlation functions than Gaussian models

Evidence of centrality dependence in correlation parameters

Potential indications of in-medium mass modifications of mesons

Abstract

Investigation of femtoscopic correlation functions in relativistic heavy ion reactions is an important tool to access the space-time structure of particle production in the sQGP. The shape of the correlation functions is often assumed to be Gaussian, but a detailed analysis reveals that the statistically correct assumption could be the so-called L\'evy distribution. The detailed analysis of correlation functions in various systems may shed light on the location of the critical endpoint on the QCD phase diagram. It could also reveal if there is partially coherent pion production or could indicate the possible in-medium mass modification of the $\eta'$ meson due to the (partial) restoration of the $U_A(1)$ axial symmetry. In this paper we present the status of the centrality dependent measurements of two-pion L\'evy Bose-Einstein correlation functions in Au+Au collisions at PHENIX.