Speaker
Description
We present a systematic approach for computing and analyzing of non-cusp and cusp perutvative series. The approach facilitates the extraction of renormalon divergences, the corresponding series ambiguity and the relation to non-perturbative power corrections. We applied it to the matching coefficients of QCD onto SCET and of (massive) SCET onto bHQET, as well as to the jet functions in both effective theories. We find full agreement with the leading flavor power of the full theory results up to $\alpha_s^4$ and predict, both analytically and numerically, the leading flavor contributions of higher orders. We also discuss through these examples how the information on renormalon divergences may be used to improve the convergence of the corresponding series.