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arXiv · 2411.08718

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

Junhuai Xu·Zhi Qin·Renjie Zou·Dawei Si·Sheng Xiao·Baiting Tian·Yijie Wang·Zhigang Xiao
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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.

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Junhuai Xu, Zhi Qin, Renjie Zou, Dawei Si, Sheng Xiao, Baiting Tian, Yijie Wang, Zhigang Xiao. 2025-02-27. Imaging Freeze-out Sources and Extracting Strong Interaction Parameters in Relativistic Heavy-Ion Collisions. https://doi.org/10.1088/0256-307x%2F42%2F3%2F031401

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