Imaging Freeze-out Sources and Extracting Strong Interaction Parameters in Relativistic Heavy-Ion Collisions

TL;DR

This paper introduces a new imaging method combining femtoscopic interferometry and optical deblurring to map the emission source in heavy-ion collisions and determine particle interaction strengths.

Contribution

It presents a novel approach to image freeze-out sources and extract strong interaction parameters simultaneously in relativistic heavy-ion collisions.

Findings

Protons and antiprotons share the same freeze-out distribution.

The emission source has higher density at the center than a Gaussian model.

Evidence of matter-antimatter symmetry at freeze-out.

Abstract

By combining femtoscopic interferometry with an optical deblurring algorithm, we present a novel method to image the source in heavy-ion collisions (HICs) while simultaneously determining the interaction strength between particle pairs. The spatial distribution of the emission source has been reconstructed for protons ($p$) and antiprotons ($\bar{p}$) from the respective $pp$ and $\bar{p}\bar{p}$ correlation functions in Au+Au collisions at $\sqrt{S_{\rm NN}}=200$ GeV. Within experimental uncertainties, protons and antiprotons share the same freeze-out distribution showing higher density in the center compared to the widely assumed Gaussian shape. The results evidence the matter-antimatter symmetry in coordinate space at the moment of freeze-out before the nucleons are fully randomized in the collisions.