Potential Nonrelativistic QCD and Heavy Quarkonium Spectrum in Next-to-Next-to-Next-to-Leading Order

Abstract

In this talk I review the calculation of the third order corrections to the heavy quarkonium spectrum in the nonrelativistic effective theory framework and its application to the phenomenology of top quark threshold production.

Comments: 5 pages LaTeX, Talk presented at RADCOR/LL 2002 conference, Kloster Banz, Germany, September 8-13, 2002