Hadronic weak decays of ${\Lambda }_c$ in the quark model

Abstract

The hadronic weak decays of ${\Lambda }_c$ are studied in the framework of a constituent quark model. With the combined analysis of the Cabbibo-favored processes, ${\Lambda }_c\to \Lambda {\pi }^{+}$, ${\Sigma }^0{\pi }^{+}$ and ${\Sigma }^{+}{\pi }^0$, we confirm that the non-factorizable transition mechanisms play a crucial role in the understanding of their compatible branching ratios. We emphasize that the SU(3) flavor symmetry breaking effects, which is generally at the order of $1\sim 2\%$, can be amplified by the destructive interferences among the pole terms in the diagrams with internal conversion. Some contributions are sensitive to the spatial distribution of the scalar-isoscalar light-quark sector in the ${\Lambda }_c$, and its overlap with the light quarks in the final state hyperon. Namely, a compact diquark configuration is disfavored.

Comments: Revtex, 21 pages, 4 figures; an error was corrected, numerical results updated, conclusion unchanged; version accepted by PRD