Exclusive $c\to s,d$ semileptonic decays of ground-state spin-1/2 and spin-3/2 doubly heavy $cb$ baryons

TL;DR

This paper calculates the semileptonic decay rates of doubly heavy $cb$ baryons involving $c o s,d$ transitions, testing heavy quark symmetry and providing approximate decay width ratios.

Contribution

It provides the first detailed evaluation of semileptonic decays of spin-1/2 and spin-3/2 doubly heavy $cb$ baryons, incorporating heavy quark symmetry constraints.

Findings

Form factors consistent with heavy quark spin symmetry

Model-independent decay width ratios predicted

Validation of theoretical constraints near zero recoil

Abstract

We evaluate exclusive semileptonic decays of ground-state spin-1/2 and spin-3/2 doubly heavy $cb$ baryons driven by a $c\to s,d$ transition at the quark level. We check our results for the form factors against heavy quark spin symmetry constraints obtained in the limit of very large heavy quark masses and near zero recoil. Based on those constraints we make model independent, though approximate, predictions for ratios of decay widths.