The neutral top-pion and the lepton flavor violating $Z$ decays $Z\to l_i{l}_j$

Abstract

Taking into account the constraints of the present experimental limit of the process $\mu \to e\gamma$ on the free parameters of topcolor-assisted technicolor(TC2) models, we calculate the contributions of the neutral top-pion to the lepton flavor violating(LFV) $Z$ decays $Z\to l_i{l}_j$. Our results show that the value of the branching ratio $Br(Z\to \tau l)$ is larger than that of $Br(Z\to \mu e)$ in all of the parameter space and there is $Br(Z\to \tau \mu )\approx Br(Z\to \tau e)\simeq 2\times 10^{-14}$, which is far from the reach of present or future experiments.

12 pages and 3 figures. To be published in J. Phys. G