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arXiv · hep-ph/0703212

Anomalous Higgs Couplings in the $SO(5)\times U(1)_{B-L}$ Gauge-Higgs Unification in Warped Spacetime

Abstract

The gauge couplings $WWZ$, $WWWW$, and $WWZZ$ in the gauge-Higgs unification scenario in the Randall-Sundrum warped spacetime remain almost universal as in the standard model, but substantial deviation results for the Higgs couplings. In the $SO(5)\times U(1)_{B-L}$ model, the couplings $WWH$ and $ZZH$ are suppressed by a factor $\cos θ_H$ from the values in the standard model, while the bare couplings $WWHH$ and $ZZHH$ are suppressed by a factor $1-(2/3)\sin^2 θ_H$. Here $θ_H$ is the Yang-Mills AB phase (Wilson line phase) along the fifth dimension, which characterizes the electroweak symmetry breaking. The suppression can be used to test the gauge-Higgs unification scenario at LHC and ILC. It is also shown that the $WWZ$ coupling in flat spacetime deviates from the standard model value at moderate values of $θ_H$, contradicting with the LEP2 data.

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Yutaka Hosotani, Yutaka Sakamura. 2007-11-08. Anomalous Higgs Couplings in the $SO(5)\times U(1)_{B-L}$ Gauge-Higgs Unification in Warped Spacetime. https://doi.org/10.1143/ptp.118.935

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