Alternative Scenarios of Relativistic Heavy-Ion Collisions: I. Baryon Stopping

TL;DR

This paper models relativistic heavy-ion collisions using different equations of state, revealing a distinctive irregularity in net-proton distributions that signals the onset of deconfinement at certain energies.

Contribution

It introduces a detailed three-fluid model analysis with various EoS, highlighting the 'peak-dip-peak-dip' pattern as a novel signature of deconfinement transition.

Findings

Crossover EoS slightly better matches experimental data.

Predicted irregularity in net-proton distributions indicates deconfinement onset.

Model covers incident energies from 2.7 to 39 GeV.

Abstract

Simulations of relativistic heavy-ion collisions within the three-fluid model employing a purely hadronic equation of state (EoS) and two versions of the EoS involving deconfinement transition are presented. The latter are an EoS with the first-order phase transition and that with a smooth crossover transition. The model setup is described in detail. The analysis is performed in a wide range of incident energies 2.7 GeV $< \sqrt{s_{NN}} <$ 39 GeV in terms of the center-of-mass energy. Results on proton and net-proton rapidity distributions are reported. Comparison with available data indicate certain preference of the crossover EoS. It is found that predictions within deconfinement-transition scenarios exhibit a "peak-dip-peak-dip" irregularity in the incident energy dependence of the form of the net-proton rapidity distributions in central collisions. This irregularity is a signal of deconfinement onset occurring in the hot and dense stage of the nuclear collision.