Dark Matter, Baryogenesis and Neutrino Oscillations from Right Handed Neutrinos

TL;DR

This paper demonstrates that the u MSM model with three right-handed neutrinos can simultaneously explain neutrino oscillations, dark matter, and baryon asymmetry without new physics beyond it, supported by comprehensive constraints and analysis.

Contribution

It provides the first complete quantitative analysis of the u MSM parameter space, including all known constraints and the evolution of neutrino abundances from the early universe.

Findings

Identifies new constraints on sterile neutrino properties from cosmological and collider data.

Re-analyzes bounds considering recent neutrino mixing angle measurements.

Offers a comprehensive guideline for future sterile neutrino searches.

Abstract

We show that, leaving aside accelerated cosmic expansion, all experimental data in high energy physics that are commonly agreed to require physics beyond the Standard Model can be explained when completing it by three right handed neutrinos that can be searched for using current day experimental techniques. The model that realises this scenario is known as Neutrino Minimal Standard Model (\nu MSM). In this article we give a comprehensive summary of all known constraints in the \nu MSM, along with a pedagogical introduction to the model. We present the first complete quantitative study of the parameter space of the model where no physics beyond the \nu MSM is needed to simultaneously explain neutrino oscillations, dark matter and the baryon asymmetry of the universe. This requires to track the time evolution of left and right handed neutrino abundances from hot big bang initial conditions down to temperatures below the QCD scale. We find that the interplay of resonant amplifications, CP-violating flavour oscillations, scatterings and decays leads to a number of previously unknown constraints on the sterile neutrino properties. We furthermore re-analyse bounds from past collider experiments and big bang nucleosynthesis in the face of recent evidence for a non-zero neutrino mixing angle \theta_{13}. We combine all our results with existing constraints on dark matter properties from astrophysics and cosmology. Our results provide a guideline for future experimental searches for sterile neutrinos. A summary of the constraints on sterile neutrino masses and mixings has appeared in arXiv:1204.3902 [hep-ph]. In this article we provide all details of our calculations and give constraints on other model parameters.