Resummation in Qcd Fractional Analytic Resummation in Qcd Fractional Analytic Perturbation Theory
نویسنده
چکیده
We describe the generalization of Analytic Perturbation Theory (APT) for QCD observables, initiated by Radyushkin, Krasnikov, Pivovarov, Shirkov, and Solovtsov, to fractional powers of coupling — Fractional APT (FAPT). The basic aspects of FAPT are shortly summarized. We describe how to treat heavy-quark thresholds in FAPT and then show how to resum perturbative series in both the one-loop APT and FAPT. As an application, we consider the FAPT description of the Higgs boson decay H0 → bb̄. The main conclusion is: To achieve an accuracy of the order of 1%, it is enough to consider up to the third correction.
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