Two-loop scalar functions with I internal lines, $I \le 5$

Abstract

This article displays a proof of concept of the mixed analytical/numerical method, presented in previous publications, to compute two-loop functions with up to five massive propagators in a scalar theory having three- and four-leg vertices as the Higgs sector of the Standard Model. Several amplitudes are considered with two, three, and four external legs. Some of them diverge in the ultraviolet region and we demonstrate that the method works in that case. It is shown that all these classes of amplitudes can be generated by four master topologies. The results of a numerical evaluation for some kinematics are presented; they are compared to public software and agree well within the error bars quoted by the different programs.