Quark model description of the \Lambda_c(2940)^+ as a molecular D^*N state and the possible existence of the \Lambda_b(6248)

Abstract

The \Lambda_c(2940)^+ baryon is studied in a constituent quark model as a molecular state composed by nucleons and D^* mesons. A bound state with the right binding energy is found for the J^\pi=3/2^- channel. The partial widths \Lambda_c(2940)^+\to ND and \Lambda_c(2940)^+\to \Sigma_c \pi are calculated and the results are consistent with the experimental data. Additionally a bottom partner \bar B^*N is predicted with a mass of 6248 MeV/c^2.