Radiative corrections to the Yukawa couplings in two Higgs doublet models

Abstract

A pattern of deviations in coupling constants of Standard Model (SM)-like Higgs boson from their SM predictions indicates characteristics of an extended Higgs sector. In particular, Yukawa coupling constants can deviate in different patterns in four types of Two Higgs Doublet Models (THDMs) with a softly-broken Z_2 symmetry. We can discriminate types of THDMs by measuring the pattern of these deviations. We calculate Yukawa coupling constants of the SM-like Higgs boson with radiative corrections in all types of Yukawa interactions in order to compare to future precision data at the International Linear Collider (ILC). We perform numerical computations of scale factors, and evaluate differences between the Yukawa couplings in THDMs and those of the SM at the one-loop level. We find that scale factors in different types of THDMs do not overlap each other even in the case with maximum radiative corrections if gauge couplings are different from the SM predictions large enough to be measured at the ILC. Therefore, in such a case, we can indirectly determine the type of the THDM at the ILC even without finding additional Higgs bosons directly.