The study of hadronic rescattering on $K^{*0}$ resonance yield in baryon-rich QCD matter

TL;DR

This paper investigates how hadronic rescattering affects the $K^{*0}$ resonance yield in baryon-rich QCD matter, highlighting the importance of baryon interactions and energy dependence in heavy-ion collisions.

Contribution

It introduces UrQMD model calculations to analyze the multiplicity dependence of the $K^{*0}/K$ ratio, emphasizing the role of baryon interactions neglected in previous models.

Findings

$K^{*0}/K$ ratio is more suppressed at lower collision energies.

Existing models neglecting baryon interactions fail to match experimental data.

Rescattering effects vary with system size and energy, affecting resonance yields.

Abstract

The effect of hadronic rescattering on $K^{*0}$ resonance yield can be studied by measuring $K^{*0}/K$ ratio as a function of centrality or multiplicity. This study investigates how the size of the system and the chemical composition (meson-meson versus meson-baryon interaction) of the matter formed in heavy-ion collisions impact the process of hadronic rescattering. It is shown that existing calculation of $K^{*0}/K$ ratio, which considers the interaction of $K^{*0}$ and $K$ mesons with only light mesons in the hadronic medium (neglecting interactions with baryons), fails to explain the measured $K^{*0}/K$ ratio at RHIC BES energies. To understand the multiplicity dependence of the $K^{*0}/K$ ratio at RHIC BES and SPS energies ($\sqrt{s_{NN}}$ $<$ 20 GeV), the Ultra Relativistic Quantum Molecular Dynamics (UrQMD) model is employed. UrQMD calculations suggest that for a given multiplicity, $K^{*0}/K$ is more suppressed in Au+Au collision at $\sqrt{s_{NN}}$ =7.7 GeV, compared to that in $\sqrt{s_{NN}}$ =200 GeV. This is possibly because of formation different type of QCD medium at 200 GeV and 7.7 GeV, and change in interaction cross-section between hadrons with change in particle type and energy.