Simultaneous Analysis in Renormalization and Factorization Scheme Dependences in Perturbative QCD

Abstract
Combined and thorough investigations of both the factorization and the renormalization scheme dependences of perturbative QCD calculations are given. Our findings are that (i) by introducing a multi-scale-dependent coupling the simultaneous parametrization of both scheme-dependences can be accomplished, (ii) Stevenson’s optimization method works quite well so that it gives a remarkable prediction which forces us to exponentiate “everything” with uncorrected subprocess cross sections, and (iii) the perturbation series in QCD may converge when Stevenson's principle of minimal sensitivity is taken into account at each order of perturbative approximation.