Strangeness Production in $\sqrt{s_{\rm NN}}=3$ GeV Au+Au Collisions at RHIC

TL;DR

This paper presents detailed measurements of strange hadron production in low-energy Au+Au collisions at RHIC, revealing insights into hadronic rescattering, medium properties, and particle production mechanisms.

Contribution

It provides the first multi-differential measurements of strange hadrons at this energy, comparing experimental data with transport and thermal models to understand collision dynamics.

Findings

Evidence of hadronic rescattering effects.

Centrality dependence of strange hadron yields.

Consistency of yields with thermal model predictions.

Abstract

We report multi-differential measurements of strange hadron production ranging from mid- to target-rapidity in Au+Au collisions at a center-of-momentum energy per nucleon pair of $\sqrt{s_{\rm NN}}=3$ GeV with the STAR experiment at RHIC. $K^0_S$ meson and $\Lambda$ hyperon yields are measured via their weak decay channels. Collision centrality and rapidity dependences of the transverse momentum spectra and particle ratios are presented. Particle mass and centrality dependence of the average transverse momenta of $\Lambda$ and $K^0_S$ are compared with other strange particles, providing evidence of the development of hadronic rescattering in such collisions. The 4$\pi$ yields of each of these strange hadrons show a consistent centrality dependence. Discussions on radial flow, the strange hadron production mechanism, and properties of the medium created in such collisions are presented together with results from hadronic transport and thermal model calculations.