Radiative neutrino mass with scotogenic scalar triplet

Vedran Brdar,Ivica Picek,Branimir Radovčić

doi:10.1016/j.physletb.2013.11.045

Abstract

We present a radiative one-loop neutrino mass model with hypercharge zero scalar triplet in conjunction with another charged singlet scalar and an additional vectorlike lepton doublet. We study three variants of this mass model: the first one without additional beyond-SM symmetry, the second with imposed DM-stabilizing discrete Z2 symmetry, and the third in which this Z2 symmetry is promoted to the gauge symmetry U(1)D. The two latter cases are scotogenic, with a neutral component of the scalar triplet as a dark matter candidate. In first scotogenic model the Z2-odd dark matter candidate is at the multi-TeV mass scale, so that all new degrees of freedom are beyond the direct reach of the LHC. In second scotogenic setup, with broken U(1)D symmetry the model may have LHC signatures or be relevant to astrophysical observations, depending on the scale of U(1)D breaking.

Highlights

The 126 GeV particle observed at the Large Hadron Collider (LHC) [1,2] corresponds to the Higgs particle h of the electroweak SU (2)L × U (1)Y extension [3] of the original Higgs model [4]
In the present attempt to account both for the mechanism of neutrino mass and for the existence of a stable dark matter (DM) we put forward a variant of the scotogenic radiative neutrino mass model by Ma [5] realized by hypercharge zero triplet scalar field
An earlier study [6] of Weinberg operator generated at one-loop level has been followed by recent classifications of radiative neutrino mass models which provide dark matter candidates, in which the present model with zero hypercharge scalar triplet is listed as type D in [7] and class T3-A in [8]

Summary

Introduction

The 126 GeV particle observed at the Large Hadron Collider (LHC) [1,2] corresponds to the Higgs particle h of the electroweak SU (2)L × U (1)Y extension [3] of the original Higgs model [4]. In the present attempt to account both for the mechanism of neutrino mass and for the existence of a stable dark matter (DM) we put forward a variant of the scotogenic radiative neutrino mass model by Ma [5] realized by hypercharge zero triplet scalar field. An earlier study [6] of Weinberg operator generated at one-loop level has been followed by recent classifications of radiative neutrino mass models which provide dark matter candidates, in which the present model with zero hypercharge scalar triplet is listed as type D in [7] and class T3-A in [8]. In the concluding section we summarize the results of the proposed variants of the model and list the constraints which may be achieved for the model parameters

Neutrino mass from an effective operator

S cS 2

Scotogenic model with Z2 symmetry

Σk and

Conclusions