Perturbative heavy quarkonium spectrum at next-to-next-to-next-to-leading order

Abstract

We compute the energy levels of some of the lower-lying heavy quarkonium states perturbatively up to O(alpha_s^5*m) and O(alpha_s^5*m*log[alpha_s]). Stability of the predictions depends crucially on the unknown 4-loop pole-MSbar mass relation. We discuss the current status of the predictions with respect to the observed bottomonium spectrum.

Comments: Short review on non-perturbative contributions included at the end; version to appear in Phys.Lett.; 7 pages, 2 figures