QCD sum rules study of \Xi_c and \Xi_b baryons

Abstract

We use QCD sum rules to study the masses of the baryons $\Xi_c$ and $\Xi_b$. We work with a current where the strange and the light quarks are in a relative spin zero, at leading order in $\alpha_s$. We consider the contributions of condensates up to dimension six. For $\Xi_b$ we get $m_{\Xi_{b}}= (5.75\pm 0.25) {\rm GeV}$, and for $\Xi_c$ we get $m_{\Xi_{c}}= (2.5\pm 0.2) {\rm GeV}$, both in excelent agreement with the experimental values. We also make predictions to the state $\Omega_b(ssb)$ obtaining m_{\Omega_{b}}= (5.82\pm 0.23) GeV.