ATLAS Collab.
Determination of the relative sign of the Higgs boson couplings to W and Z bosons using WH production via vector-boson fusion with the ATLAS detector
Examples of leading-order Feynman diagrams for VBF WH production, where the Higgs boson interacts with either a W or Z boson. These diagrams interfere destructively if the Higgs boson couplings to W and Z have the same sign, and constructively if they have opposite sign.