Top Quark Pair Production and Decay Near Threshold in e+e- Collisions

Abstract

We review the physics involved in the production and decay of top quarks in e^+e^- -> ttbar near threshold, with special emphasis on the recent theoretical study on the decay process of top quarks in the threshold region. The energy-angular distribution of l^+ in semileptonic top decays is calculated including the full O(alpha_s) corrections. Various effects of the final-state interactions are elucidated. A new observable is defined near threshold, which depends only on the decay of free polarized top quarks, and thus it can be calculated without bound-state effects or the final-state interactions.

Comments: 17 pages, LaTeX