Minimal Left-Right Symmetric Dark Matter

TL;DR

This paper demonstrates that minimal left-right symmetric models can naturally include stable TeV-scale dark matter particles without extra stabilizing symmetries, using existing model features and minimal parameters.

Contribution

It introduces a simple way to incorporate stable dark matter in left-right models via accidental or residual symmetries, with minimal new parameters and viable dark matter candidates.

Findings

Viable two-component dark matter from fermion triplets and quintuplets.

Stability arises from accidental symmetry or residual  subgroup.

Models can explain recent ATLAS diboson excess with a 2 TeV gauge boson.

Abstract

We show that left-right symmetric models can easily accommodate stable TeV-scale dark matter particles without the need for an ad-hoc stabilizing symmetry. The stability of a newly introduced multiplet arises either accidentally as in the Minimal Dark Matter framework or comes courtesy of the remaining unbroken $\mathbb{Z}_2$ subgroup of $B-L$. Only one new parameter is introduced: the mass of the new multiplet. As minimal examples we study left-right fermion triplets and quintuplets and show that they can form viable two-component dark matter. This approach is in particular valid for $SU(2)\times SU(2)\times U(1)$ models that explain the recent diboson excess at ATLAS in terms of a new charged gauge boson of mass 2 TeV.