Structure of charmed baryons studied by pionic decays

Abstract

We investigate the decays of the charmed baryons aiming at the systematic understanding of hadron internal structures based on the quark model by paying attention to heavy quark symmetry. We evaluate the decay widths from the one pion emission for the known excited states, Λ_c^*(2595), Λ_c^*(2625), Λ_c^*(2765), Λ_c^*(2880) and Λ_c^*(2940), as well as for the ground states Σ_c(2455) and Σ_c^*(2520). The decay properties of the lower excited charmed baryons are well explained, and several important predictions for higher excited baryons are given. We find that the axial-vector type coupling of the pion to the light quarks is essential, which is expected from chiral symmetry, to reproduce the decay widths especially of the low lying Λ_c^* baryons. We emphasize the importance of the branching ratios of Γ(Σ_c^*π)/Γ(Σ_cπ) for the study of the nature of higher excited Λ_c^* baryons.

20 pages, 5 figures, 11 tables