Semileptonic $s\to u$ decays of singly heavy baryons

TL;DR

This paper investigates semileptonic $s o u$ decays of singly heavy baryons using a light-front quark model, providing form factors including $f_3$ and $g_3$, analyzing heavy quark limits, and predicting decay observables relevant for testing the Standard Model.

Contribution

The study introduces a comprehensive calculation of all form factors for $s o u$ decays in a light-front approach, including typically inaccessible form factors, and explores heavy quark limit effects.

Findings

Form factors $f_3$ and $g_3$ are calculated explicitly.

Heavy quark limit results differ from previous literature.

Lepton flavor universality is sensitive to lepton masses in these decays.

Abstract

$s\to u$ weak decays of heavy flavor hadrons play a unique role in the field of heavy flavor physics. In this work, we investigate semileptonic $s\to u$ decays of singly heavy baryons in the light-front approach under the three-quark picture. Firstly, we provide all the form factors using this quark model, especially for $f_{3}$ and $g_{3}$, which are usually considered non-extractable in recent literature. We also discuss the heavy quark limit for the form factors, and some of our results differ from those in the literature. We find that, when considering the heavy quark limit, the $m_{s}$ correction may not be negligible. Secondly, we apply the obtained form factors to predict some observables in semileptonic decays. It is worth noting that, due to the extremely small phase space, lepton flavor universality (LFU) is sensitive to the masses of leptons, and precise measurement of LFU is expected to be an important tool for testing the standard model.