Sterile neutrinos, dark matter, and the pulsar velocities in models with a Higgs singlet

TL;DR

The range of parameters for which the sterile neutrinos can simultaneously explain the cosmological dark matter and the observed velocities of pulsars is identified.

Abstract

We identify the range of parameters for which the sterile neutrinos can simultaneously explain the cosmological dark matter and the observed velocities of pulsars. To satisfy all cosmological bounds, the relic sterile neutrinos must be produced sufficiently cold. This is possible in a class of models with a gauge-singlet Higgs boson coupled to the neutrinos. Sterile dark matter can be detected by the x-ray telescopes. The presence of the singlet in the Higgs sector can be tested at the Large Hadron Collider.

Figures (1)

• Figure 1: The x-ray limits reported in Ref.x-rays (dashed line) apply if the sterile neutrinos account for all the dark matter ($\Omega_s=0.2$). The value of $\Omega_s$ depends on the production mechanisms, but it cannot be lower than the amount produced via DW mechanism dw (except for the low-reheat scenarios low-reheatdeGouvea:2006gz). The model-independent exclusion plot (purple region) is obtained by assuming this minimal value. A sterile neutrino with mass 3 keV and $\sin^2 \theta \approx 3\times 10^{-9}$, produced at some temperature above 100 GeV, can explain both pulsar kicks and dark matter.