Higgs decay into two leptons and a photon revisited

TL;DR

This paper provides updated Standard Model predictions for the decay rates and asymmetries of Higgs boson decays into two leptons and a photon, highlighting the dependence on experimental cuts and presenting specific branching ratios and asymmetry values.

Contribution

It offers new detailed calculations of differential decay rates and forward-backward asymmetries for Higgs decays into leptons and a photon, considering experimental cut dependencies.

Findings

Branching ratio for H→e+e−γ is 5.8×10−5.

Branching ratio for H→μ+μ−γ is 6.4×10−5.

Forward-backward asymmetry for electrons is 0.343.

Abstract

I present new results for the Standard-Model predictions of the differential decay rates for $H\to \ell^{+} \ell^{-} \gamma$, where $\ell=e, \mu$, and the forward-backward asymmetries defined in terms of the flight direction of the photon corresponding to the lepton momenta. The results dependend on the cuts on energies and invariant masses of the final state particles. For standard choices of these cuts the branching ratios $B(H\to e \bar e \gamma)=5.8\cdot 10^{-5}$ and $B(H\to \mu \bar \mu \gamma)=6.4\cdot 10^{-5}$ as well as the forward-backward asymmetries $\mathcal{A}^{(e)}_{\text{FB}}=0.343$ and $\mathcal{A}^{(\mu)}_{\text{FB}}=0.255$ have been found.