Loop-Induced Higgs Boson Decays into Gauge Bosons in Radiative Natural Supersymmetry

TL;DR

This paper analyzes loop-induced Higgs decays into gauge bosons within Radiative Natural Supersymmetry, providing analytical expressions and exploring parameter space regions that enhance the rare decay h→Zγ while remaining consistent with experimental constraints.

Contribution

It reproduces one-loop MSSM calculations for Higgs decay widths and identifies parameter space regions that maximize the h→Zγ decay rate without conflicting with current measurements.

Findings

h→Zγ decay width can reach about 7.5 keV, compatible with ATLAS data.

h→γγ decay remains close to Standard Model predictions, deviations less than 5%.

h→gg channel shows about 12% suppression in the considered parameter space.

Abstract

In this article, we study loop-induced Higgs decays into gauge bosons within the framework of Radiative Natural Supersymmetry. We reproduce the one-loop MSSM calculations for the Higgs partial decay widths into a Z boson-photon pair, two photons, and two gluons, providing the corresponding analytical expressions for the scattering amplitudes. We focus on the region of parameter space that maximizes the rare decay width of the process $h \to Z\gamma$, and analyze the correlated predictions for the remaining Higgs decay channels. In the selected region of parameter space, the $h \to Z\gamma$ decay width is enhanced, reaching a maximum value of $\simeq 7.5~\mathrm{keV}$, while remaining compatible with the current ATLAS measurement. At the same time, this region satisfies current Higgs constraints from the $h \to \gamma\gamma$ and $h \to gg$ channels. The diphoton mode remains close to the Standard Model expectation, with deviations at the level of $\lesssim 5\%$. The gluon channel exhibits a stronger sensitivity to the considered region of parameter space, leading to a moderate suppression of about $12\%$ in the corresponding partial width.