Identified charged hadron production in Au+Au collisions at $\sqrt{s_\mathrm{NN}}$ = 54.4 GeV with the STAR detector

TL;DR

This paper reports on the production and properties of identified charged hadrons in Au+Au collisions at 54.4 GeV, analyzing particle yields, ratios, and system dynamics to understand particle production mechanisms.

Contribution

It provides new measurements of hadron production, freezeout parameters, and energy density at this collision energy, comparing results with theoretical models.

Findings

Particle yields and ratios are measured at 54.4 GeV.

Kinetic freezeout parameters are extracted.

Energy density estimates are provided and compared with models.

Abstract

We present results on the production of $\pi^{\pm}$, $K^{\pm}$, $p$, and $\bar{p}$ in Au+Au collisions at $\sqrt{s_\mathrm{NN}}$ = 54.4~GeV using the STAR detector at RHIC, at midrapidity ($|y| <$ 0.1). Invariant yields of these particles as a function of transverse momentum are shown. We determine bulk properties such as integrated particle yields ($dN/dy$), mean transverse momentum ($\langle p_{T} \rangle$), particle ratios, which provide insight into the particle production mechanisms. Additionally, the kinetic freezeout parameters ($T_\text{kin}$ and $\langle \beta_{T} \rangle$), which provide information about the dynamics of the system at the time of freezeout, are obtained. The Bjorken energy density ($\epsilon_{\rm{BJ}}$), which gives an estimate of the energy density in the central rapidity region of the collision zone at the formation time $\tau$, is calculated and presented as a function of multiplicity for various energies. The results are compared with those from the models such as A Multi-Phase Transport (AMPT) and Heavy Ion Jet INteraction Generator (HIJING) for further insights.