Constraints on top quark FCNC from electroweak precision measurements
High Energy Physics - Phenomenology
2009-11-10 v2
Abstract
We study the one-loop contributions of the effective flavor changing neutral couplings (FCNC) tcZ and tcH on the electroweak precision observables Gamma_Z, R_c, R_b, R_l, A_c and A^FB_c. Using the known experimental limits on these observables, we may place 95% CL bounds on these FCNC couplings which in turn translate into the following limits for the branching ratios: BR(t -> cZ) < 6.7 10^-2 and BR(t -> cH) < (0.09 - 2.9) 10^-3 for 114 < m_H < 170 GeV.
Cite
@article{arxiv.hep-ph/0412222,
title = {Constraints on top quark FCNC from electroweak precision measurements},
author = {F. Larios and R. Martinez and M. A. Perez},
journal= {arXiv preprint arXiv:hep-ph/0412222},
year = {2009}
}
Comments
10 pages, 3 figures. References added. Errors corrected. Numerical results for BR have changed