Strange hadron production in a quark combination model in Au+Au collisions at RHIC energies

TL;DR

This study uses a quark combination model to successfully describe strange hadron production and yield ratios in Au+Au collisions across a range of RHIC energies, highlighting the importance of quark coalescence at hadronization.

Contribution

The paper demonstrates that the equal velocity combination model effectively reproduces transverse momentum spectra and yield ratios of strange hadrons in Au+Au collisions at various energies, emphasizing the role of quark coalescence.

Findings

Successfully describes $p_{T}$ spectra of strange hadrons.

Reproduces yield ratios of anti-hadrons to hadrons.

Highlights the significance of quark coalescence at low RHIC energies.

Abstract

We apply a quark combination model to study yield densities and transverse momentum ($p_{T}$) spectra of strange (anti-)hadrons at mid-rapidity in central Au+Au collisions at $\sqrt{s_{NN}}=$ 7.7, 11.5, 19.6, 27, 39 and 200 GeV. We show that experimental data for $p_{T}$ spectra of (anti-)hadrons in these collisions can be systematically described by the equal velocity combination of constituent quarks and antiquarks at hadronization. We obtain $p_{T}$ spectra of quarks and antiquarks at hadronization and study their collision energy dependence. We also reproduce the yield densities of hadrons and anti-hadrons. In particular, we demonstrate that yield ratios of anti-hadrons to hadrons $K^{-}/K^{+}$, $\bar{p}/p$, $\bar{\Lambda}/\Lambda$, $\bar{\Xi}^{+}/\Xi^{-}$ and $\bar{\Omega}^{+}/\Omega^{-}$ simply correlate with each other and their experimental data except $\bar{\Omega}^{+}/\Omega^{-}$ at $\sqrt{s_{NN}}=$ 7.7 GeV are systematically described by the model. These results suggest that the equal velocity combination mechanism for quarks and antiquarks at hadronization plays an important role in Au+Au collisions at low RHIC energies ($\sqrt{s_{NN}}\geq$ 11.5 GeV).