Investigating ${\Omega }_c$ spectroscopy in two-body ${\Omega }_b$ decays

Abstract

We investigate the $1S$-, $1P$-, $2S$-, and $1D$-wave ${\Omega }_c(css)$ spectroscopy through the non-leptonic decays of ${\Omega }_b^{-}$ baryon within the constituent quark model. For the lowest-lying $1S$-wave ${\Omega }_c$ state, we obtain the branching fractions $\mathcal{B}({\Omega }_b^{-}\to {\Omega }_c^0{\pi }^{-},{\Omega }_c^0{\rho }^{-})=(1.2,6.3)\times 10^{-3}$, which are consistent with existing model predictions. For ${\Omega }_c(3000)$, ${\Omega }_c(3050)$, ${\Omega }_c(3065)$, and ${\Omega }_c(3090)$, observed in the proton-proton and $e^{+}{e}^{-}$ collisions and interpreted as members of the $1P$-wave multiplet (collectively denoted as ${\Omega }_c^{\ast \ast }$), we predict the branching fractions of ${\Omega }_b^{-}\to {\Omega }_c^{\ast \ast }{\pi }^{-},{\Omega }_c^{\ast \ast }{\rho }^{-}$ at the level of $10^{-3}$. Assigning the newly observed ${\Omega }_c(3327)$ baryon to a $1D$-wave excitation with $J^P=5/2^{+}$ or $7/2^{+}$, we obtain $\mathcal{B}[{\Omega }_b^{-}\to {\Omega }_c(3327{)}^0{\pi }^{-},{\Omega }_c(3327{)}^0{\rho }^{-}]=(2.0,5.7)\times 10^{-3}$ or $(4.6,0.8)\times 10^{-3}$, respectively. The pronounced differences between these two scenarios provide a clear discriminant that can be tested in future measurements at LHCb.

17 pages,1 figure