Doubly-charged scalar bosons from the doublet

TL;DR

This paper explores extended Higgs models with a hypercharge 3/2 doublet, focusing on the collider phenomenology of doubly charged scalars and their role in neutrino mass generation and dark matter.

Contribution

It introduces new models with hypercharge 3/2 doublets, analyzing their collider signatures and implications for neutrino masses and dark matter, distinct from traditional models.

Findings

Doubly charged scalars exhibit unique collider signatures.

Models can distinguish themselves from Y=2 singlet or triplet scenarios.

Different phenomenological aspects are identified at the LHC.

Abstract

We consider the extended Higgs models, in which one of the isospin doublet scalar fields carries the hypercharge Y=3/2. Such a doublet field $\Phi_{3/2}$ is composed of a doubly charged scalar boson as well as a singly charged one. We first discuss a simple model with $\Phi_{3/2}$ (Model I), and study its collider phenomenology at the LHC. We then consider a new model for radiatively generating neutrino masses with a dark matter candidate (Model II), in which $\Phi_{3/2}$ and an extra Y=1/2 doublet as well as vector-like singlet fermions carry the odd quantum number for an unbroken discrete $Z_2$ symmetry. We also discuss the neutrino mass model (Model III), in which the exact $Z_2$ parity in Model II is softly broken. It is found that the doubly charged scalar bosons in these models show different phenomenological aspects from those which appear in models with a Y=2 isospin singlet field or a Y=1 triplet one. They could be clearly distinguished at the LHC.