LHC sensitivity to the decay of a Higgs boson to tau mu

TL;DR

This paper evaluates the LHC's potential to detect or constrain lepton flavor violating Higgs decays to tau and muons, estimating the sensitivity with current data and implications for Higgs couplings.

Contribution

It provides the first sensitivity estimate for Higgs to tau mu decays at the LHC using 20 inverse-fb of data, highlighting the potential to set new bounds.

Findings

LHC could set a 95% CL bound BR(h -> tau mu) < 4.5 x 10^{-3}

Corresponds to a Yukawa coupling of order the Cheng-Sher ansatz

Analysis focuses on gluon fusion production and leptonic tau decays

Abstract

We study the sensitivity of the LHC, with 20 inverse-fb of data, to lepton flavour violating Higgs boson decays h -> tau+ mu- (and h -> tau+ e-). We consider the large population of Higgses produced in gluon fusion, combined with leptonic decays of the tau, and estimate that the LHC could set a 95 % confidence level bound BR(h -> tau mu) < 4.5 \times 10^{-3}. This correponds to a coupling of order the Cheng-Sher ansatz y_{tau mu} = sqrt{m_tau m_mu/v^2}.