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arXiv · 2312.06468

Constraints on initial baryon stopping and equation of state from directed flow

Lipei Du·Chun Shen·Sangyong Jeon·Charles Gale
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Abstract

Our investigation focuses on the rapidity-dependent directed flow, $v_1(y)$, of identified hadrons in Au+Au collisions across a broad range of $\sqrt{s_{\rm NN}}$ from 7.7 to 200 GeV. Employing a (3+1)-dimensional hybrid framework, our study successfully reproduces the characteristic features of the measured $v_1(y)$ for both mesons and baryons across the considered beam energies. Notably, our analysis reveals the constraining power of baryonic $v_1(y)$ on the initial baryon stopping mechanism. Together with mesonic $v_1(y)$, the directed flow serves as a crucial tool for probing the equation of state governing dense nuclear matter at finite chemical potentials.

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Lipei Du, Chun Shen, Sangyong Jeon, Charles Gale. 2023-12-11. Constraints on initial baryon stopping and equation of state from directed flow. https://arxiv.org/abs/2312.06468

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