Top-Charm Strong Flavor-Changing Neutral Currents at the Tevatron

Abstract

The possibility of an anomalous coupling between the top and charm quarks and the gluon field is explored in a model-independent way using an effective Lagrangian that is gauge-invariant under a non-linear realization of SU(3)$_{C} \times$ SU(2$)_{L} \times$ U(1$)_{Y}$. Even for the current 200 $pb^{-1}$ of integrated luminosity at the Tevatron, the new physics scale that strongly modifies the coupling of t-c-g must be larger than about 2.5 TeV if no signal is found within a 3$σ$ confidence limit. For 1 $fb^{-1}$ of data, this constraint can be pushed up to 3.8 TeV.

25 pages, 2 postscript figures using epsf.sty This replacement includes the correction of a few errors which have small effects on the results. It is the version to be published in Phys Rev D