The decay rate of the Higgs decay H→Zγ is evaluated at the one-loop level in the SO(5)×U(1) gauge-Higgs unification. Although an infinite number of loops with Kaluza-Klein states contribute to the decay amplitude, there appears the cancellation among the loops, and the decay rate is found to be finite and non-zero. It is found that the decay rate is well approximated by the decay rate in the standard model multiplied by cos2θH, where θH is the Aharonov-Bohm phase induced by the vacuum expectation value of an extra-dimensional component of the gauge field.
@article{arxiv.1510.06550,
title = {$H\to Z\gamma$ in the gauge-Higgs unification},
author = {Shuichiro Funatsu and Hisaki Hatanaka and Yutaka Hosotani},
journal= {arXiv preprint arXiv:1510.06550},
year = {2016}
}