A Model-independent Description of New Physics effects in e+e- to t tbar

Abstract

We study the potential of a future $e^{+}{e}^{-}$ collider for the search of anomalous gamma t t bar and Z t t bar couplings, assuming that CP-invariance holds. This is done in a model-independent way, considering that all six possible couplings do appear. Two experimental situations are envisaged, with and without electron beam polarization. Observability limits in the form of domains in the 6-dimensional parameter space are established. Illustrations for specific constrained models are also presented and implications for new physics searches are discussed.

Comments: 26 pages and 5 figures. e-mail: renard@lpmsun2.lpm.univ-montp2.fr