1301.4694 (Chian-Shu Chen et al.)

New Scalar Contributions to $h\to Zγ$    [PDF]

Chian-Shu Chen, Chao-Qiang Geng, Da Huang, Lu-Hsing Tsai

We calculate the decay rate of $h\to Z\gamma$ by including the contributions from new scalars with arbitrary quantum numbers of the weak isospin ($T$) and hypercharge ($Y$) in the standard model. We find that our general formula for the decay rate of $h\to Z\gamma$ matches with that for $h\to \gamma\gamma$ in the limit of $m_Z=0$, but it is different from those in the literature. To illustrate our result, by taking the current $2\sigma$ excess of the $h\to \gamma\gamma$rate measured by the LHC, we examine the corresponding shift for the $Z\gamma$ decay channel due to the new scalar. We show that the enhancement or reduction of the $h\to Z\gamma$ rate only depends on the relative size of $T$ and the absolute value of $Y$. Explicitly, we predict $0.76View original: http://arxiv.org/abs/1301.4694