Open Strange and Open Heavy Flavour mesons in Asymmetric Nuclear Matter within Quark Meson Coupling model

TL;DR

This paper investigates how open strange, charm, and bottom mesons behave in asymmetric nuclear matter using the Quark Meson Coupling model, revealing in-medium modifications and isospin-dependent mass splittings relevant for heavy ion collision experiments.

Contribution

It introduces a detailed analysis of in-medium properties of open heavy flavor mesons considering scalar and vector meson couplings, including isospin effects, within the QMC model.

Findings

Mass splittings within isodoublets due to isospin asymmetry.

Significant medium modifications of meson excitation energies.

Large isospin effects at high baryon densities.

Abstract

The in-medium properties of open strange ($K$, $\bar{K}$), open charm ($D$, $\bar{D}$), and open bottom ($B$, $\bar{B}$) mesons are investigated in asymmetric nuclear matter using Quark Meson Coupling (QMC) model. A direct coupling of scalar ($\sigma$, $\delta$) and vector ($\omega$, $\rho$) mesons to the light quarks and anti-quarks of these mesons give rise to the in-medium modification of the properties of the corresponding meson within the model. The inclusion of the $\delta$ (scalar iso-vector) meson breaks the isospin symmetry for the masses of the light quark and antiquark doublets, causing mass splitting between ($u,\;d$) as well as ($\bar{d},\;\bar{u}$). Consequently, the considered mesons exhibit mass splittings within the isodoublets of $K$, $\bar{K}$, $D$, $\bar{D}$, $B$ and $\bar{B}$ mesons when embedded in asymmetric nuclear matter. In the current study, the interactions of the pseudoscalar meson with the scalar, as well as vector mesons, are considered, which lead to significant medium modifications of the excitation energies of the open strange (charm and bottom) mesons. In asymmetric nuclear matter, due to the interaction of the pseudoscalar meson with the vector iso-vector $\rho$ meson, there is a splitting in the excitation energies of the mesons within the isospin doublets. The isospin effects are seen to be large for high baryon densities. This study can have significant observable consequences, such as in the production ratios, e.g., $K^+/K^0$, $K^-/\bar {K^0}$, $D^+/D^0$, $D^-/\bar{D}^0$, $B^+/B^0$ and $B^-/\bar{B}^0$ in the upcoming heavy ion collision experiments at FAIR project at GSI, where the experiments are planned to be performed using neutron-rich beams to study the compressed baryonic matter.