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arXiv · 2410.20704

Fluctuations and correlations of quark spin in hot and dense QCD matter

Hao-Lei Chen·Wei-jie Fu·Xu-Guang Huang·Guo-Liang Ma
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Abstract

In this work, we examine the impact of QCD phase transitions on the quark spin fluctuations and correlations. We propose the quark-antiquark correlation, which relates to the vector meson spin alignment and the $\Lambda-\bar\Lambda$ correlation, can be used as a novel probe of the critical end point (CEP) in the QCD phase diagram. Using the Nambu-Jona-Lanisio model, we qualitatively study the properties of quark-antiquark spin correlations. Our findings reveal a peak structure near the CEP of the chiral phase transition, which may serve as an experimental signature of the CEP and account for the non-monotonic behavior of $\phi$ meson alignment at low collision energies observed recently in experiments.

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Hao-Lei Chen, Wei-jie Fu, Xu-Guang Huang, Guo-Liang Ma. 2024-10-28. Fluctuations and correlations of quark spin in hot and dense QCD matter. https://arxiv.org/abs/2410.20704

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