Analysis of the $\Sigma_Q$ baryons in the nuclear matter with the QCD sum rules

TL;DR

This paper investigates how $\Sigma_Q$ baryons, specifically $\Sigma_c$ and $\Sigma_b$, are affected by nuclear matter using QCD sum rules, revealing significant mass shifts in the process.

Contribution

The study extends previous work by deriving coupled QCD sum rules for $\Sigma_Q$ baryons in nuclear matter, including effects of unequal pole residues and normalization to experimental data.

Findings

Mass shifts of $\Sigma_c$ and $\Sigma_b$ in nuclear matter are -123 MeV and -375 MeV.

Developed coupled QCD sum rules for baryon masses, self-energies, and residues.

Incorporated effects of unequal pole residues and vacuum normalization.

Abstract

In this article, we extend our previous work to study the $\Sigma$-type heavy baryons $\Sigma_c$ and $\Sigma_b$ in the nuclear matter using the QCD sum rules, and obtain three coupled QCD sum rules for the masses $M_{\Sigma_Q}^*$, vector self-energies $\Sigma_v$ and pole residues $\lambda^*_{\Sigma_Q}$ in the nuclear matter. Then we take into account the effects of the unequal pole residues from different spinor structures, and normalize the masses from the QCD sum rules in the vacuum to the experimental data, and obtain the mass-shifts $\delta M_{\Sigma_c}=-123\,\rm{MeV}$ and $\delta M_{\Sigma_b}=-375\,\rm{MeV}$ in the nuclear matter.