The Higgs - photon - Z boson coupling revisited
Abstract
We analyze the coupling of CP-even and CP-odd Higgs bosons to a photon and a Z boson in extensions of the Standard Model. In particular, we study in detail the effect of charged Higgs bosons in two-Higgs doublet models, and the contribution of SUSY particle loops in the minimal supersymmetric extension of the Standard Model. The Higgs-
γZ
coupling can be measured in the decay
Z→γ
+Higgs at
e
+
e
−
colliders running on the Z resonance, or in the reverse process Higgs
→Zγ
with the Higgs boson produced at LHC. We show that a measurement of this coupling with a precision at the percent level, which could be the case at future
e
+
e
−
colliders, would allow to distinguish between the lightest SUSY and standard Higgs bosons in large areas of the parameter space.