Dipolar dark matter in light of 3.5 keV X-ray Line, Neutrino mass and LUX data

TL;DR

This paper proposes a minimal extension to the Standard Model that explains the 3.5 keV X-ray line, neutrino masses, and dark matter detection constraints by introducing right-handed neutrinos, a charged scalar, and an extra Higgs doublet.

Contribution

It introduces a simple model linking neutrino mass generation, X-ray line signal, and dark matter detection within a unified framework.

Findings

Decay of heavy neutrino explains 3.5 keV X-ray line

Model compatible with LUX dark matter detection limits

Neutrino masses are naturally explained

Abstract

A simple extension of the standard model (SM) providing transient magnetic moments to right-handed neutrinos is presented. In this model, the decay of next-to-lightest right-handed heavy neutrino to the lightest one and a photon (N 2 -> N 1 + gamma) can explain the 3.5 keV X-ray line signal observed by XMM-Newton X-ray observatory. Beside the SM particles and heavy right-handed Majorana neutrinos, the model contains a singly charged scalar (H) and an extra Higgs doublet (Sigma). Within this minimal set of extra fields the sub-eV masses of left-handed neutrinos are also explained. Moreover, we show that the spin-independent DM-nucleon cross-section is compatible with latest LUX data.