A New Decoupling Theorem in Top-Quark Physics

Abstract

Angular distribution of a secondary particle in top-quark production/decay is studied in a simple and general manner. It is shown that the distribution does not depend on any possible anomalous top-quark-decay interactions whatever the production mechanism is when certain well-justified conditions are satisfied. Some analyses using the final- state lepton are presented as an example of its application.

7 pages, Latex, one eps-figure, Talk at International Workshop on Physics and Experiments with Future Electron-Positron Linear Colliders (LCWS2002), August 26 - 30, 2002, Jeju-island, Korea