Charged pion production from Au + Au collisions at $\sqrt{s_{NN}}=2.4$ GeV in the Relativistic Vlasov-Uehling-Uhlenbeck model

TL;DR

This study uses the relativistic Vlasov-Uehling-Uhlenbeck model to analyze charged pion production in gold-gold collisions at 2.4 GeV, successfully reproducing experimental data and highlighting the importance of medium effects.

Contribution

It introduces a density-dependent $ riangle$ resonance cross section in the RVUU model to better match experimental pion multiplicities in heavy-ion collisions.

Findings

Good agreement with experimental $^ extpm$ rapidity and transverse momentum distributions.

Identification of the need to include strong potential effects on $^ extpm$ in the model.

Proton rapidity distribution comparison with experimental data.

Abstract

Using the isospin-dependent relativistic Vlasov-Uehling-Uhlenbeck (RVUU) model, we study charged pion ($\pi^\pm$) production in Au+Au collisions at $\sqrt{s_{NN}}=$ 2.4 GeV. By fitting the density dependence of the $\Delta$ resonance production cross section in nuclear medium to reproduce the experimental $\pi^\pm$ multiplicities measured by the HADES Collaboration, we obtain a good description of the rapidity distributions and transverse momentum spectra of $\pi^\pm$ in collisions at various centralities. Some shortcomings in the description of $\pi^{\pm}$ production may indicate the need for including the strong potential on $\pi^\pm$ in RVUU, which is at present absent. We also calculate the proton rapidity distribution in the most central collisions and compare with the coalescence invariant proton rapidity distribution extracted from preliminary HADES data.