Speaker
Paul Frederik Depta
(Max-Planck-Institut für Kernphysik)
Description
We propose a novel mechanism to generate sterile neutrinos $\nu_s$ in the early Universe, by converting ordinary neutrinos $\nu_\alpha$ in scattering processes $\nu_s \nu_\alpha \to \nu_s \nu_s$. After initial production by oscillations, this leads to an exponential growth in the sterile neutrino abundance. We show that such a production regime naturally occurs for self-interacting sterile neutrinos, and that this opens up significant new parameter space where sterile neutrinos make up all of the observed dark matter. Our results provide strong motivation to further push the sensitivity of X-ray line searches, and to improve on constraints from structure formation.
Primary author
Paul Frederik Depta
(Max-Planck-Institut für Kernphysik)
Co-authors
Torsten Bringmann
(University of Oslo)
Marco Hufnagel
(Service de Physique Théorique, Université Libre de Bruxelles)
Jörn Kersten
(University of Bergen)
Joshua Ruderman
(New York University)
Kai Schmidt-Hoberg
(Deutsches Elektronen-Synchrotron DESY)
