Semileptonic $\Lambda_b \to \bar \nu_l l \Lambda_c(2595)$ and $\Lambda_b \to \bar \nu_l l \Lambda_c(2625)$ decays in the molecular picture of $\Lambda_c(2595)$ and $\Lambda_c(2625)$

TL;DR

This paper investigates the semileptonic decays of Lambda_b baryons into Lambda_c(2595) and Lambda_c(2625) resonances, supporting their molecular nature as dynamically generated states from D N and D* N interactions, and emphasizes the importance of the D* N component.

Contribution

It provides a theoretical analysis of decay rates supporting the molecular picture of Lambda_c resonances, highlighting the role of D* N interactions neglected previously.

Findings

The decay rate ratio aligns with experimental data.

The D* N coupling is crucial for accurate predictions.

Supports the molecular interpretation of Lambda_c(2595) and Lambda_c(2625).

Abstract

We evaluate the partial decay widths for the semileptonic $\Lambda_b \to \bar \nu_l l \Lambda_c(2595)$ and $\Lambda_b \to \bar \nu_l l \Lambda_c(2625)$ decays from the perspective that these two $\Lambda^*_c$ resonances are dynamically generated from the $DN$ and $D^*N$ interaction with coupled channels. We find that the ratio of the rates obtained for these two reactions is compatible with present experimental data and is very sensitive to the $D^* N$ coupling, which becomes essential to obtain agreement with experiment. Together with the results obtained for the $\Lambda_b \to \pi^- \Lambda^*_c$ reactions, it gives strong support to the molecular picture of the two $\Lambda^*_c$ resonances and the important role of the $D^*N$ component neglected in prior studies of the $\Lambda_c(2595)$ from the molecular perspective.