Perturbative heavy quark-antiquark systems

Abstract

In this review I cover recent developments concerning the construction of non-relativistic effective theories for perturbative heavy quark-antiquark systems and heavy quark mass definitions. I then discuss next-to-next-to-leading order results on quarkonium masses and decay, top quark pair production near threshold and QCD sum rules for ${\rm Y}$ mesons.

Comments: 22 pages, LaTeX, Contribution to the 8th International Symposium on Heavy Flavour Physics, Southampton, UK, 25-29 July 1999