Doubly Cabibbo-suppressed decays of antitriplet charmed baryons

Abstract

Doubly Cabibbo-suppressed (DCS) nonleptonic weak decays of antitriplet charmed baryons are studied systematically in this work. The factorizable and nonfactorizable contributions can be classified explicitly in the topological-diagram approach and treated separately. In particular, the evaluation of nonfactorizable terms is based on the pole model in conjunction with current algebra. All three types of relevant non-perturbative parameters contributing factorizable and nonfactorizable terms are estimated in the MIT bag model. Branching fractions of all the DCS decays are predicted to be of order $10^{-4}\sim 10^{-6}$. In particular, we find that the three modes ${\Xi }_c^{+}\to {\Sigma }^{+}{K}^0,{\Sigma }^0{K}^{+}$ and ${\Xi }_c^0\to {\Sigma }^{-}{K}^{+}$ are as large as $(1\sim 2)\times 10^{-4}$, which are the most promising DCS channels to be measured. We also point out that the two DCS modes ${\Xi }_c^{+}\to {\Sigma }^{+}{K}^0$ and ${\Xi }_c^0\to {\Sigma }^0{K}^0$ are possible to be distinguished from ${\Xi }_c^{+}\to {\Sigma }^{+}{K}_S$ and ${\Xi }_c^0\to {\Sigma }^0{K}_S$. The decay asymmetries for all the channels with a kaon in their final states are found to be large in magnitude and negative in sign.

Comments: 19 pages, 2 figures, 4 tables