Investigating the transition form factors of $\Lambda_b\to\Lambda_c(2625)$ and $\Xi_b\to\Xi_c(2815)$ and the corresponding weak decays with support from baryon spectroscopy

TL;DR

This paper calculates form factors and decay rates for specific baryon transitions using a light-front quark model supported by baryon spectroscopy, providing predictions consistent with experimental data and accessible at LHCb.

Contribution

It introduces a detailed calculation of transition form factors and decay rates for $Lambda_b$ and $Xi_b$ baryons using a three-body light-front quark model with baryon spectroscopy inputs, advancing theoretical understanding.

Findings

Branching ratios for semileptonic decays reach about 1%.

The calculated $Lambda_b^0 oLambda_c^+(2625)\mu^- u_{\mu}$ branching ratio matches experimental data.

Nonleptonic decay widths to $\pi^-$, $ ho^-$, and $D_s^{(*)-}$ are significant and potentially observable at LHCb.

Abstract

We calculate the form factors of the $\Lambda_b\to\Lambda_c(2625)$ and $\Xi_b\to\Xi_c(2815)$ transitions, and additionally evaluate the corresponding semileptonic decays and the color-allowed two-body nonleptonic decays. In order to obtain the concerned form factors, we use the three-body light-front quark model with the support from baryon spectroscopy. In this work, as important physical inputs, the spatial wave functions of concerned baryons are obtained by the Gaussian expansion method with a semirelativistic potential model. For the semileptonic processes, the branching ratios of the electron and muon channels can reach up to the order of magnitude of $1\%$, where our result $\mathcal{B}(\Lambda_b^0\to\Lambda_c^+(2625)\mu^-\nu_{\mu})=(1.641\pm0.113)\%$ is consistent with the current experimental data. As for the nonleptonic processes, the decays to $\pi^-$, $\rho^-$, and $D_s^{(*)-}$ final states have considerable widths. These discussed decay modes could be accessible at the LHCb experiment.