Infrared scalar one-loop three point integrals in loop regularization

Abstract

The infrared divergent scalar three-point integrals are evaluated by the loop regularization method. Three kinds of infrared divergent integrals, i.e., massless triangle diagram, triangle diagrams with one and two massive internal lines, are systematically evaluated by loop regularization, analytic results are obtained. According the method, the infrared divergences are regulated by the so-called sliding scale $\mu_{s}$ which plays the role of infrared cutoff. The amplitudes obtained through loop regularization depend on $\mu_{s}$ such that we may extract different contribution by varying $\mu_{s}$. Some general results for evaluation of scale one-loop triangle diagram are also derived.