Light Sterile Neutrinos: Models and Phenomenology

Abstract

Motivated by recent hints in particle physics and cosmology, we study the realization of eV-scale sterile neutrinos within both the seesaw mechanism and flavor symmetry theories. We show that light sterile neutrinos can rather easily be accommodated in the popular A_4 flavor symmetry models. The exact tri-bimaximal mixing pattern is perturbed due to active-sterile mixing, which we discuss in detail for one example. In addition, we find an interesting extension of the type I seesaw, which can provide a natural origin for eV-scale sterile neutrinos as well as visible admixtures between sterile and active neutrinos. We also show that the presence of sterile neutrinos would significantly change the observables in neutrino experiments, specifically the oscillation probabilities in short-baseline experiments and the effective mass in neutrino-less double beta decay. The latter can prove particularly helpful to strengthen the case for eV-scale sterile neutrinos.

30 pages, 6 figures; v2: minor additions, references added, matches published version

References in corpus (16)

• The Reactor Antineutrino Anomaly
• Phenomenology with Massive Neutrinos
• A possible symmetry of the $\nu$MSM
• Sterile neutrino oscillations after first MiniBooNE results
• Deviation from tri-bimaximal neutrino mixing in A4 flavor symmetry
• Neutrino physics from precision cosmology
• Using BBN in cosmological parameter extraction from CMB: a forecast for Planck
• Soft L_e-L_mu-L_tau flavour symmetry breaking and sterile neutrino keV Dark Matter
• Signature of sterile species in atmospheric neutrino data at neutrino telescopes
• Searching for sterile neutrinos in ice
• Detecting sterile neutrinos with KATRIN like experiments
• Testing the very-short-baseline neutrino anomalies at the solar sector
• Sterile neutrinos: direct mixing effects versus induced mass matrix of active neutrinos
• Turbulent Supernova Shock Waves and the Sterile Neutrino Signature in Megaton Water Detectors
• MiniBooNE Results and Neutrino Schemes with 2 sterile Neutrinos: Possible Mass Orderings and Observables related to Neutrino Masses
• Possible, alternative explanations of the T2K observation of the nu_e appearance from an initial nu_mu