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arXiv · 1510.06550

$H\to Zγ$ in the gauge-Higgs unification

Abstract

The decay rate of the Higgs decay $H \to Z γ$ is evaluated at the one-loop level in the $SO(5)\times U(1)$ 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 $\cos^2θ_H$, where $θ_H$ is the Aharonov-Bohm phase induced by the vacuum expectation value of an extra-dimensional component of the gauge field.

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Shuichiro Funatsu, Hisaki Hatanaka, Yutaka Hosotani. 2016-09-03. $H\to Zγ$ in the gauge-Higgs unification. https://doi.org/10.1103/physrevd.92.115003

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