One-loop analytical expressions for <i>gg</i>/<i>γγ</i> → <i>ϕ_iϕ_j </i> in Higgs extensions of the standard model and their applications*

Abstract General one-loop formulas for loop-induced processes with are presented in this paper. The analytic expressions evaluated in this study are valid for a class of Higgs Extensions of the Standard Model, e.g., Inert Doublet Higgs, Two Higgs Doublet, Zee-Babu, and Triplet Higgs Models . Analytic expressions for one-loop form factors are expressesd in terms of the basic scalar one-loop two-, three-, and four-point functions following the output format of the packages and . Hence, physical results can be evaluated numerically using one of these packages. The analytic results are tested using several checks such as the ultraviolet finiteness and infrared finiteness of the one-loop amplitudes. Furthermore, the amplitudes obey the ward identity due to massless gauge bosons in the initial states. This identity is also verified numerically. Regarding applications, we present the phenomenological results for the investigated processes in the Zee-Babu model as a typical example. In particular, production cross-sections for the processes are scanned over the parameter space of the Zee-Babu Model.