Radiative corrections to Higgs coupling constants in two Higgs doublet models

AbstractA pattern of deviations in the Standard Model (SM) like Higgs boson (h) couplings from their SM predictions depends on the structure of the Higgs sector and the Yukawa interaction. In particular, in Two Higgs Doublet Models (THDMs) with a softly-broken Z2 symmetry, different characteristic patterns of deviation in Yukawa coupling constants (hff‾) can be allowed depending on four types of Yukawa interactions. We calculate hff‾ coupling constants at the one-loop level in all the types of THDMs. Even if there is no deviation in the hff‾ couplings at the tree level, they can deviate from the SM predictions by a few percent due to extra Higgs boson loop contributions. We find that if the deviations in the gauge couplings hVV(V=Z,W) are found with an enough large to be measured at the International Linear Collider (ILC), the scale factors for the hff‾ couplings do not overlap among the THDMs with four types of Yukawa interactions even taking into account the radiative corrections. Therefore, in such a case, we can indirectly determine the type of the THDMs at the ILC even without information from direct searches of the additional Higgs bosons