Identified hadron production at mid-rapidity in Au+Au collisions at $\sqrt{s_{NN}} = 54.4$ GeV at STAR

TL;DR

This paper reports on the measurement of identified hadron spectra at mid-rapidity in Au+Au collisions at 54.4 GeV, providing insights into the bulk properties and freeze-out conditions of the quark-gluon plasma.

Contribution

It presents the first detailed transverse momentum spectra and freeze-out parameters for identified hadrons at this collision energy, expanding understanding of QGP properties.

Findings

Particle yields and ratios vary with collision centrality.

Freeze-out parameters depend on collision centrality.

Results are compared with data at other energies.

Abstract

Quantum Chromodynamics (QCD) predicts that at sufficiently high temperature ($T$) and/or baryon chemical potential ($\mu_B$), the state of matter is in the form of quarks and gluons, which are no longer confined within hadrons. This deconfined state of matter is known as the Quark-Gluon Plasma (QGP). The goal of relativistic heavy-ion collision experiments is to create such a hot and dense state of matter and study its properties. Measurements of identified particle spectra in Au+Au collisions provide information on the bulk properties, such as integrated yield ($dN/dy$), average transverse momenta ($\langle p_T \rangle$), particle ratios, and freeze-out parameters of the medium produced. The systematic study of bulk properties sheds light on the particle production mechanism in these collisions. Also, the centrality dependence of the freeze-out parameters provides an opportunity to explore the QCD phase diagram. In this talk, we will present the transverse momentum spectra of identified hadrons ($\pi^{\pm}$, $K^{\pm}$, $p$, and $\bar{p}$) at mid-rapidity ($|y| < 0.1$) in Au+Au collisions at $\sqrt{s_{\mathrm{NN}}} = 54.4$ GeV. The centrality dependence of $dN/dy$, particle ratios, and kinetic freeze-out parameters will also be presented, and their physics implications will be discussed. In addition, we will compare our results with previously published results at other collision energies.