Measurement of the branching fractions of the Cabibbo-favored decays $\hat{I}{›}_c^{+}\to \hat{I}›K_S^0{K}^{+}$ and $\hat{I}{›}_c^{+}\to \hat{I}{ž}^0{K}_S^0\ddot{I}{€}^{+}$ and search for $\hat{I}{›}_c^{+}\to \hat{I}{\pounds }^0{K}_S^0{K}^{+}$

Abstract

Based on $e^{+}{e}^{-}$ collision data corresponding to an integrated luminosity of about 4.5 fb${}^{-1}$ collected at center-of-mass energies between 4599.53 MeV and 4698.82 MeV with the BESIII detector, the absolute branching fraction of the Cabibbo-favored decay $\hat{I}{›}_c^{+}\to \hat{I}›K_S^0{K}^{+}$ is measured to be $(3.12\pm 0.46\pm 0.15)\times 10^{-3}$. Combined with a previous measurement from the BESIII Collaboration, the branching fraction of the decay $\hat{I}{›}_c^{+}\to \hat{I}›K_S^0{K}^{+}$ is calculated to be $(3.07\pm 0.26\pm 0.13)\times 10^{-3}$. The decay $\hat{I}{›}_c^{+}\to \hat{I}{ž}^0{K}_S^0\ddot{I}{€}^{+}$ is observed for the first time with a statistical significance of $6.6\ddot{I}ƒ$, and its branching fraction is determined to be $(3.70\pm 0.60\pm 0.21)\times 10^{-3}$. In addition, a search for the decay $\hat{I}{›}_c^{+}\to \hat{I}{\pounds }^0{K}_S^0{K}^{+}$ is performed and its branching fraction is determined to be $(0.80_{-0.24}^{+0.28}\pm 0.16)\times 10^{-3}$, corresponding to an upper limit of $1.28\times 10^{-3}$ at $90\%$ confidence level. These measurements provide new information that can be used to distinguish between theoretical models.