Signature of Pseudo Nambu-Goldstone Higgs boson in its Decay

TL;DR

This paper proposes using the ratio of Higgs decay signals to identify if the Higgs boson is a pseudo Nambu-Goldstone boson, by analyzing the $h ightarrow Z\gamma$ process to distinguish it from other effects.

Contribution

It introduces a method to detect the PNGB nature of the Higgs via the ratio of decay signals, isolating effects free from nonlinearity influences.

Findings

The $h ightarrow Z\gamma$ decay ratio effectively signals the PNGB Higgs.

This ratio can distinguish PNGB Higgs signatures from other coupling deviations.

The method reduces contamination from heavy particle effects in Higgs decay analyses.

Abstract

If the Higgs boson is a pseudo Nambu-Goldstone boson (PNGB), the $hZ\gamma$ contact interaction induced by the $\mathcal{O}(p^4)$ invariants of the non-linear sigma model is free from its nonlinearity effects. The process $h\rightarrow Z\gamma$ can be used to eliminate the universal effects of heavy particles, which can fake the nonlinearity effects of the PNGB Higgs boson in the process $h\rightarrow V^*V$ ($V=W^\pm$,\ $Z$). We demonstrate that the ratio of the signal strength of $h\rightarrow Z\gamma$ and $h\rightarrow V^*V$ is good to distinguish the signature of the PNGB Higgs boson from Higgs coupling deviations.