An effective gauge-Higgs operators analysis of new physics associated with the Higgs

TL;DR

This paper investigates new physics effects related to the 125 GeV Higgs boson using gauge-invariant dimension-six operators, analyzing Higgs production, decays, and electric dipole moments to constrain possible deviations from the Standard Model.

Contribution

It provides a model-independent analysis of Higgs-related new physics effects through effective operators, highlighting constraints from EDMs and potential CP violation in specific decay channels.

Findings

Higgs decay channels align with SM within uncertainties

Neutron and electron EDMs strongly constrain CP-violating effects

Potential large CP violation in h→γγ and h→γZ channels

Abstract

We study the new physics(NP) related to the recent discovered 125 GeV Higgs by employing an important subset of the standard model(SM) gauge invariant dimension-six operators constructed by the the SM Higgs and gauge fields. Explicitly, we perform a model-independent study on the production and decays of the Higgs, the electric dipole moments(EDM) of the neutron and the electron, and we take into account the anomalous magnetic dipole moments of muon and electron as well. We find that, even all Higgs decay channels agree with the SM predictions, the SM theoretical uncertainties provide a lot of room to host NP associated with the 125 GeV boson. A linear relation is revealed in our numerical study that $\mu_{ZZ}\simeq \mu_{WW}$ and $ 0.6 \lesssim \mu_{ZZ,WW} \lesssim 1.4$ at 95% CL with or without the EDM's constraints. The neutron and electron EDM's severely constrain the relevant Wilson coefficients. Therefore the CP violating components in the $h\rightarrow WW, ZZ$ channels are too small, $\sim{\cal O}(10^{-5})$, to be detected at LHC. However, we point out that even the parity of the 125GeV boson has been largely determined to be even in the $h\to ZZ$ channel, one should pay special attention to the potentially large CP violation in the $h\to \gamma\gamma$ and $h\to \gamma Z$ channels. This should be seriously checked in the future spin correlation experiments.