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arXiv · 2208.12091

The high-density equation of state in heavy-ion collisions: Constraints from proton flow

Jan Steinheimer·Anton Motornenko·Agnieszka Sorensen·Yasushi Nara·Volker Koch·Marcus Bleicher
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Abstract

A set of different equations of state is implemented in the molecular dynamics part of a non-equilibrium transport simulation (UrQMD) of heavy-ion collisions. It is shown how different flow observables are affected by the density dependence of the equation of state. In particular, the effects of a phase transition at high density are explored, including an expected reduction in mean $m_T$. We also show that an increase in $v_2$ is characteristic for a strong softening of the equation of state. The phase transitions with a low coexistence density, $n_{\mathrm{CE}}<4 n_0$, show a distinct minimum in the slope of the directed flow as a function of the beam energy, which would be a clear experimental signal. By comparing our results with experimental data, we can exclude any strong phase transition at densities below $4n_0$.

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Jan Steinheimer, Anton Motornenko, Agnieszka Sorensen, Yasushi Nara, Volker Koch, Marcus Bleicher. 2022-08-25. The high-density equation of state in heavy-ion collisions: Constraints from proton flow. https://doi.org/10.1140/epjc%2Fs10052-022-10894-w

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