Analysis of the ${\Lambda }_Q$ baryons in the nuclear matter with the QCD sum rules

Abstract

In this article, we study the ${\Lambda }_c$ and ${\Lambda }_b$ baryons in the nuclear matter using the QCD sum rules, and obtain the in-medium masses $M_{{\Lambda }_c}^{\ast }=2.335\mathrm{GeV}$, $M_{{\Lambda }_b}^{\ast }=5.678\mathrm{GeV}$, the in-medium vector self-energies ${\Sigma }_v^{{\Lambda }_c}=34\mathrm{MeV}$, ${\Sigma }_v^{{\Lambda }_b}=32\mathrm{MeV}$, and the in-medium pole residues ${\lambda }_{{\Lambda }_c}^{\ast }=0.021{\mathrm{GeV}}^3$, ${\lambda }_{{\Lambda }_b}^{\ast }=0.026{\mathrm{GeV}}^3$. The mass-shifts are $M_{{\Lambda }_c}^{\ast }-M_{{\Lambda }_c}=51\mathrm{MeV}$ and $M_{{\Lambda }_b}^{\ast }-M_{{\Lambda }_b}=60\mathrm{MeV}$, respectively.

Comments: 7 pages, 8 figures, revised version