The Vertex Corrections in Technicolor Model without Exact Custodial Symmetry

Abstract

We discuss the effects of isospin breaking which appear in the vertex corrections for $Zb\bar{b}$, $Z{\tau }^{+}{\tau }^{-}$ and $W\nu \tau$ in a one-family technicolor model without exact custodial symmetry. By means of the effective lagrangian approach we compute the vertex corrections for $Zb\bar{b}$, $Z\tau \tau$ and $W\tau \nu$ taking account of the contributions from technivectormesons. If the isospin symmetry in technilepton sector is not exact, technivectormesons contribute to the vertex correction for $Z\tau \tau$ but such contributions to the correction for $W\tau \nu$ are absent. If the difference is measured, it is the evidence of the isospin breaking.

Comments: 15 pages, Latex, uses epic.sty, 4 figyres appended as a compressed uuencoded postscript file