Spectroscopy, leptonic decays and the nature of heavy quarkonia

We examine the electronic width ratios of Gamma resonances below the B (B) over bar threshold by means of an effective (Cornell-type) QCD potential incorporating 1/m(b) corrections obtained from a prior fit to the bottomonium spectrum. From our analysis we conclude that the Gamma(2S) and Gamma(3S) states should belong to the strong-coupling (nonperturbative) regime while the Gamma(1S) state should belong to the weak-coupling (perturbative) regime, in agreement with a previous study based on radiative decays. (C) 2008 Elsevier B.V. All rights reserved.