Rare Semileptonic Decays of Heavy Mesons with Flavor SU(3) Symmetry

TL;DR

This paper calculates the decay rates of rare semileptonic heavy meson decays using flavor SU(3) symmetry, estimating their tiny branching ratios and potential detectability at future experiments.

Contribution

It provides the first systematic calculation of these rare decay processes and assesses their experimental sensitivities considering SU(3) symmetry breaking effects.

Findings

Decay rates are extremely small within the Standard Model.

Branching ratios are estimated with SU(3) symmetry and breaking effects.

Future experiments may have sensitivity to these rare decays.

Abstract

In this paper, we calculate the decay rates of $D^+ \to D^0 e^+ \nu$, $D^+_S \to D^0 e^+ \nu$, $B^0_S \to B^+ e^- \bar{\nu}$, $D^+_S \to D^+ e^- e^+$ and $B^0_S \to B^0 e^-e^+$ semileptonic decay processes, in which only the light quarks decay, while the heavy flavors remain unchanged. The branching ratios of these decay processes are calculated with the flavor SU(3) symmetry. The uncertainties are estimated by considering the SU(3) breaking effect. We find that the decay rates are very tiny in the framework of the Standard Model. We also estimate the sensitivities of the measurements of these rare decays at the future experiments, such as BES-III, super-$B$ and LHC-$b$.