We study the new physics related to the recently discovered 125 GeV Higgs by employing an important subset of the standard model (SM) gauge-invariant dimension-6 operators constructed by 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 (EDMs) of the neutron and the electron, and we take into account the anomalous magnetic dipole moments of the muon and electron as well. We find that, even if all Higgs decay channels agree with the SM predictions, the SM theoretical uncertainties provide a lot of room to host new phyiscs 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% C.L. with or without the EDM constraints. The neutron and electron EDMs severely constrain the relevant Wilson coefficients. Therefore the $CP$-violating components in the $h\to WW$, $ZZ$ channels are too small, $\sim \mathcal{O}({10}^{-5})$, to be detected at the LHC. However, we point out that, even though the parity of the 125 GeV 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.

• Received 4 April 2013

DOI:https://doi.org/10.1103/PhysRevD.88.033004