Light composite scalar boson from a see-saw mechanism in two-scale TC models

Abstract

We consider the possibility of a light composite scalar boson arising from mass mixing between a relatively light and heavy scalar singlets in a see-saw mechanism expected to occur in two-scale Technicolor (TC) models. A light composite scalar boson can be generated when the TC theory features two technifermions species in different representations, $R_1$ and $R_2$, under a single technicolor gauge group, with characteristic scales $\Lambda_1$ and $\Lambda_2$. We determine the final composite scalar fields, $\Phi_1$ and $\Phi_2$, effective theory using the effective potential for composite operators approach. To generate a light composite scalar it is enough to have a walking (or quasi-conformal) behavior just for one of the technifermions representations.