An explanation of one loop induced $h\to \mu \tau$ decay

TL;DR

This paper proposes a one-loop model with vector-like leptons and scalars to explain the $h o $ excess, dark matter, and muon g-2 discrepancy simultaneously, while remaining consistent with experimental constraints.

Contribution

Introduction of a new one-loop model with vector-like leptons and scalars that accounts for $h o $ excess, dark matter, and muon g-2.

Findings

Can explain $h o $ excess of ~1%.

S_1 scalar as a dark matter candidate consistent with relic abundance.

Potential production of S_2 at 14 TeV LHC.

Abstract

We discuss a possibility to explain the excess of $h\to\mu\tau$ at one-loop level. We introduce three generation of vector-like lepton doublet $L'$ and two singlet scalars $S_{1,2}$ which are odd under $Z_2$, while all the standard model fields are even under this discrete symmetry. We show that $S_1$ can be a good dark matter candidate. We show that we can explain the dark matter relic abundance, large part of the discrepancy of muon $g-2$ between experiments and the standard model predictions, as well as the $h\to\mu\tau$ excess of $\sim 1$ %, while evading constraints from experiments of dark matter direct detection and charged lepton flavor violating processes. We also consider prospects of production of $S_2$ at LHC with energy $\sqrt{s}=14$ TeV.