Toward discovering the excited $\Omega$ baryons through nonleptonic weak decays of ${\Omega }_c$

Abstract

The nonleptonic weak decay processes ${\Omega }_c\to \Omega {\pi }^{+}/\Omega (1P){\pi }^{+}/\Omega (1D){\pi }^{+}/\Omega (2S){\pi }^{+}$ are studied using the constituent quark model. The branching fraction of ${\Omega }_c\to \Omega {\pi }^{+}$ is predicted to be $1.0\%$. Considering the newly observed $\Omega (2012)$ resonance as a conventional $1P$-wave $\Omega$ excite state with spin-parity $J^P=3/2^{-}$, the newly measured ratio $\mathcal{B}[{\Omega }_c\to \Omega (2012){\pi }^{+}\to (\Xi \bar{K}{)}^{-}{\pi }^{+}]/\mathcal{B}[{\Omega }_c\to \Omega {\pi }^{+}]$ at Belle can be well understood. Besides, the production rates for the missing $1P-$wave state $\Omega (1^2{P}_{1/2^{-}})$, two spin quartet $1D-$wave states $\Omega (1^4{D}_{1/2^{+}})$ and $\Omega (1^4{D}_{3/2^{+}})$, and two $2S$-wave states $\Omega (2^2{S}_{1/2^{+}})$ and $\Omega (2^4{S}_{3/2^{+}})$ are also investigated. It is expected that these missing excited $\Omega$ baryons should have large potentials to be discovered through the nonleptonic weak decays of ${\Omega }_c$ in forthcoming experiments by Belle II and/or LHCb.

Comments: 11 pages,4 figures