Supersymmetric correction to top quark pair production near threshold

We studied the leading supersymmetric contribution to top-antitop threshold production using the NRQCD framework. The one-loop matching to the potenti al and the Wilson coefficient of the leading S-3(1) production current were considered. We point out that the leading correction to the potential is z ero due to SU(3)(c) gauge invariance. This is true in general for any new p hysics that enters above the electroweak scale. The shape of the top quark pair production cross section is therefore almost unaffected near threshold , allowing a precise determination of the top quark mass based on the Stand ard Model calculations. The supersymmetric correction to the Wilson coeffic ient cl of the production current decouples for heavy super particles. Its contribution is smaller than the Standard Model next-to-next-leading-log re sults. (C) 2001 Published by Elsevier Science B.V.