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arXiv · 1606.07673

Pseudoscalar - sterile neutrino interactions: reconciling the cosmos with neutrino oscillations

Maria Archidiacono·Stefano Gariazzo·Carlo Giunti·Steen Hannestad·Rasmus Hansen·Marco Laveder·Thomas Tram
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Abstract

The Short BaseLine (SBL) neutrino oscillation anomalies hint at the presence of a sterile neutrino with a mass of around 1 eV. However, such a neutrino is incompatible with cosmological data, in particular observations of the Cosmic Microwave Background (CMB) anisotropies. However, this conclusion can change by invoking new physics. One possibility is to introduce a secret interaction in the sterile neutrino sector mediated by a light pseudoscalar. In this pseudoscalar model, CMB data prefer a sterile neutrino mass that is fully compatible with the mass ranges suggested by SBL anomalies. In addition, this model predicts a value of the Hubble parameter which is completely consistent with local measurements.

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Maria Archidiacono, Stefano Gariazzo, Carlo Giunti, Steen Hannestad, Rasmus Hansen, Marco Laveder, Thomas Tram. 2016-08-31. Pseudoscalar - sterile neutrino interactions: reconciling the cosmos with neutrino oscillations. https://doi.org/10.1088/1475-7516%2F2016%2F08%2F067

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