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 $\nu_s$ abundance. We show that such a production regime naturally occurs for self-interacting $\nu_s$, and that this opens up significant new parameter space where $\nu_s$ 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
(Oslo University)
Marco Hufnagel
(ULB)
Joern Kersten
(University of Bergen)
Joshua T. Ruderman
(Center for Cosmology and Particle Physics, Department of Physics, New York University)
Kai Schmidt-Hoberg
(DESY)
