Nonleptonic two-body decays of single heavy baryons $\Lambda_Q$, $\Xi_Q$, and $\Omega_Q$ $(Q=b,c)$ induced by $W$ emission in the covariant confined quark model

TL;DR

This paper investigates nonleptonic two-body decays of heavy baryons induced by W emission using a covariant confined quark model, providing decay rates, branching fractions, and asymmetry parameters, with a focus on decays involving lepton pairs.

Contribution

It applies the covariant confined quark model to calculate tree-level decay contributions of heavy baryons, offering predictions and comparisons with experimental data and other theories.

Findings

Calculated decay rates and branching fractions for selected baryon decays.

Analyzed decay asymmetry parameters and angular distributions.

Included lepton mass effects in decay analyses.

Abstract

We have made a survey of heavy-to-heavy and heavy-to-light nonleptonic heavy baryon two-body decays and have identified those decays that proceed solely via $W$-boson emission, i.e. via the tree graph contribution. Some sample decays are $\Omega_{b}^{-}\to\Omega_{c}^{(*)0}\rho^{-}(\pi^{-}),\, \Omega_{b}^{-}\to\Omega^{-}J/\psi(\eta_{c}),\, \Xi_{b}^{0,-}\to\Xi^{0,-}J/\psi(\eta_{c}),\, \Lambda_{b}\to \Lambda J/\psi(\eta_{c}),\, \Lambda_{b}\to \Lambda_{c} D_{s}^{(\ast)},\, \Omega_{c}^{0}\to\Omega^{-}\rho^{+}(\pi^{+})$, and $\Lambda_c \to p \phi$. We make use of the covariant confined quark model previously developed by us to calculate the tree graph contributions to these decays. We calculate rates, branching fractions and, for some of these decays, decay asymmetry parameters. We compare our results to experimental findings and the results of other theoretical approaches when they are available. Our main focus is on decays to final states with a lepton pair because of their clean experimental signature. For these decays we discuss two-fold polar angle decay distributions such as in the cascade decay $\Omega_{b}^{-}\to\Omega^{-}(\to \Xi\pi,\Lambda K^{-})+J/\psi(\to \ell^{+}\ell^{-})$. Lepton mass effects are always included in our analysis.