Higgs boson decay to lepton pair and photon and possible non-Hermiticity of the Yukawa interaction

Abstract

The production of lepton pairs in the Higgs boson decay $h\to {\ell }^{+}{\ell }^{-}\gamma$ is studied. The emphasis is put on the structure of the Higgs boson interaction with the fermions. This interaction is chosen as a mixture of the scalar and pseudo-scalar couplings, and, in addition, it is supposed to be non-Hermitian. We study prediction of this model for the observables in the $h\to {\ell }^{+}{\ell }^{-}\gamma$ decay for the $e^{+}{e}^{-}$, ${\mu }^{+}{\mu }^{-}$ and ${\tau }^{+}{\tau }^{-}$ pairs. The differential decay width and lepton forward-backward asymmetry are calculated as functions of the dilepton invariant mass for several sets of $hf\bar{f}$ coupling constants. The influence of non-Hermitian $hf\bar{f}$ interaction on the forward-backward asymmetry is studied, and large influence of a possible non-Hermiticity of the Higgs interaction with the top quarks on forward-backward asymmetry for $e^{+}{e}^{-}$ and ${\mu }^{+}{\mu }^{-}$ pairs is stressed.

Comments: 8 pages, 3 figures, ujp style