Transverse Momentum Dependence of Intercept Parameter \lambda of Two-Pion (-Kaon) Correlation Functions in q-Bose Gas Model

Abstract

Within recently proposed approach aimed to effectively describe the observed non-Bose type behavior of the intercept \lambda of two-particle correlation function C(p,K) of identical pions or kaons detected in heavy-ion collisions, the q-deformed oscillators and q-Bose gas picture are employed. For the intercept \lambda, connected with deformation parameter q, the model predicts a fully specified dependence of \lambda on pair mean momentum {\bf K}. The intercepts \lambda_\pi and \lambda_K for pions and kaons, differing noticeably at small {\bf K}, should merge at {\bf K} large enough, i.e., in the range |{\bf K}| \ge 800 MeV/c, where the effect of resonance decays is negligible. In this paper we confront, fixing q appropriately, the predicted dependence \lambda_\pi=\lambda_\pi({\bf K}) with recent results from STAR/RHIC for \pi^-\pi^- and \pi^+\pi^+ pairs, and find nice agreement. Using the same q, we also predict behavior of \lambda for kaons.