Calculation of binding energies and masses of quarkonia in analytic QCD models

Understand

We extract MSbar quark masses mqbar (q=b,c) from the evaluation of the masses of quarkonia Upsilon(1S) and J/\psi(1S), performed in two analytic QCD models, and in perturbative QCD in two renormalization schemes.

• In analytic QCD the running coupling has no unphysical singularities in the low-momentum regime.
• We apply the analytic model of Shirkov et al.[Analytic Perturbation Theory (APT)], extended by Bakulev et al.[Fractional Analytic Perturbation Theory (FAPT)], and the two-delta analytic model (2delanQCD).
• The latter, in contrast to (F)APT, at higher energies basically coincides with the perturbative QCD (in the same scheme).