Two-particle interferometry for the sources undergoing first-order QCD phase transition in high energy heavy ion collisions

Abstract

We investigate the two-particle interferometry for the particle-emitting sources which undergo the first-order phase transition from the quark-gluon plasma with a finite baryon chemical potential to hadron resonance gas. The effects of source expansion, lifetime, and particle absorption on the transverse interferometry radii $R_{\rm out}$ and $R_{\rm side}$ are examined. We find that the emission durations of the particles become large when the system is initially located at the boundary between the mixed phase and the quark-gluon plasma. In this case, the difference between the radii $R_{\rm out}$ and $R_{\rm side}$ increases with the transverse momentum of the particle pair significantly. The ratio of $\sqrt{R_{\rm out}^2 -R_{\rm side}^2}$ to the transverse velocity of the pair is an observable for the enhancement of the emission duration.