Predictions for the $${\varvec{\Lambda }_b \rightarrow J/\psi ~ \Lambda (1405)}$$ Λ b → J / ψ Λ ( 1405 ) decay

Abstract

We calculate the shape of the [Formula: see text] and [Formula: see text] invariant mass distributions in the [Formula: see text] and [Formula: see text] decays that are dominated by the [Formula: see text] resonance. The weak interaction part is the same for both processes and the hadronization into the different meson-baryon channels in the final state is given by symmetry arguments. The most important feature is the implementation of the meson-baryon final-state interaction using two chiral unitary models from different theoretical groups. Both approaches give a good description of antikaon-nucleon scattering data, the complex energy shift in kaonic hydrogen and the line shapes of [Formula: see text] in photoproduction, based on the two-pole scenario for the [Formula: see text]. We find that this reaction reflects more the higher mass pole and we make predictions of the line shapes and relative strength of the meson-baryon distributions in the final state.