Electroweak precision constraints on the electroweak-scale right-handed neutrino model

TL;DR

This paper examines how electroweak precision measurements constrain a model with right-handed neutrinos at the electroweak scale, impacting its phenomenological viability and potential signals at colliders.

Contribution

It provides a detailed analysis of electroweak precision constraints on the electroweak-scale right-handed neutrino model, including additional scalars and mirror fermions.

Findings

Electroweak parameters S, T, U impose significant constraints on the model.

Allowed parameter space for new particles is identified.

Model remains viable within certain electroweak precision bounds.

Abstract

A model of electroweak-scale right-handed neutrino (\ewnur) model was constructed five years ago in which the right-handed neutrinos are members of mirror fermion weak doublets and where the Majorana masses of the right-handed neutrinos are found to be {\em naturally} of the order of the electroweak scale. These features facilitate their searches at the LHC through signals such as like-sign dilepton events. This model contains, in addition to the mirror quarks and leptons, extra scalars transforming as weak triplets. In this paper, we study the constraints imposed on these additional particles by the electroweak precision parameters S, T, and U. These constraints are crucial in determining the viability of the electroweak $\nu_R$ model and the allowed parameter space needed for a detailed phenomenology of the model.