Characteristic quantities of pion-emitting sources extracted by model-independent analysis in relativistic heavy ion collisions

TL;DR

This paper uses model-independent imaging analysis to extract characteristic quantities of pion-emitting sources in relativistic heavy ion collisions, revealing source geometry and coherence, and proposing an improved granular source model that matches experimental data.

Contribution

It introduces an improved granular source model for quark-gluon plasma droplets that accurately reproduces experimental pion correlation functions and source characteristics.

Findings

The moments of pion pair separation reveal source geometry and coherence.

The granular source model reproduces experimental two-pion correlation functions.

Transverse-momentum dependence aligns with interferometry results after Lorentz contraction considerations.

Abstract

We examine the characteristic quantities of pion-emitting sources extracted by model-independent imaging analysis in relativistic heavy ion collisions. The moments of the spatial separation of pion pair emission can provide the characteristic information about the source geometry and coherence. They are better for describing the non-Gaussian sources with granular and core-halo structures. An improved granular source model of quark-gluon plasma droplets can reproduce the main characteristics of the two-pion correlation functions and source functions in the experiment of $\sqrt{s_{\rm NN}}=200$ GeV Au+Au collisions. The transverse-momentum dependence of the normalized first-order moments of the separation for the granular source is consistent with that of the usual interferometry results of source radii, after taking into account the Lorentz contraction in the direction of transverse momentum of pion pair.