Top Decay in Topcolor-Assisted Technicolor

Abstract

Conventional technicolor models with light charged technipions (${\pi }_T^{\pm }$) lead to an unacceptably large contribution to $t\text{ra}{\pi }_T^{+}b$ decay rate. Topcolor-assisted technicolor models also have additional PGBs called top-pions (${\pi }_t^{\pm }$) which may contribute to this decay. We study the potentially dangerous mixing of charged top-pion and technipions in toy models of `natural' topcolor-assisted technicolor. We find that the $t\text{ra}{\pi }_{t,T}^{+}b$ decay rate in such models can be within experimental limits due to a combination of heavy top-pion and small ${\pi }_t-{\pi }_T$ mixing.

Comments: 10 pages, 1 figure, TeX, harvmac.tex