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

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 $\sqrt{s_{\mathrm{NN}}}$ 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.

4 pages, 1 figure. Contribution to the proceedings of Quark Matter 2023 (Houston, TX, 3-9 Sep. 2023)