Hidden beauty baryon states in the local hidden gauge approach with heavy quark spin symmetry

Abstract

Using a coupled channel unitary approach, combining the heavy quark spin symmetry and the dynamics of the local hidden gauge, we investigate the meson-baryon interaction with hidden beauty and obtain several new states of $N^{\ast }$ around 11 GeV. We consider the basis of states ${\eta }_{b}N$, ${\rm Y}N$, $B{\Lambda }_b$, $B{\Sigma }_b$, $B^{\ast }{\Lambda }_b$, $B^{\ast }{\Sigma }_b$, $B^{\ast }{\Sigma }_b^{\ast }$ and find four basic bound states which correspond to $B{\Sigma }_b$, $B{\Sigma }_b^{\ast }$, $B^{\ast }{\Sigma }_b$ and $B^{\ast }{\Sigma }_b^{\ast }$, decaying mostly into ${\eta }_{b}N$ and ${\rm Y}N$ and with a binding energy about 50-130 MeV with respect to the thresholds of the corresponding channel. All of them have isospin $I=1/2$, and there are no bound states or resonances in $I=3/2$. The $B{\Sigma }_b$ state appears in $J=1/2$, the $B{\Sigma }_b^{\ast }$ in $J=3/2$, the $B^{\ast }{\Sigma }_b$ appears nearly degenerate in $J=1/2,3/2$ and the $B^{\ast }{\Sigma }_b^{\ast }$ appears nearly degenerate in $J=1/2,3/2,5/2$. These states have a width from $6\sim 45\text{mev}$ except for the one in $J=5/2$ which has zero width since it cannot decay into any of the states of the basis chosen.

Comments: misprint corrected