Sterile Neutrinos and Flavor Ratios in IceCube

Understand

The flavor composition of astrophysical neutrinos observed in neutrino telescopes is a powerful discriminator between different astrophysical neutrino production mechanisms and can also teach us about the particle physics properties of neutrinos.

• In this paper, we investigate how the possible existence of light sterile neutrinos can affect these flavor ratios.
• We consider two scenarios: (i) neutrino production in conventional astrophysical sources, followed by partial oscillation into sterile states; (ii) neutrinos from dark matter decay with a primary flavor composition enhanced in tau neutrinos or sterile neutrinos.
• Throughout the paper, we constrain the sterile neutrino mixing parameters from a full global fit to short and long baseline data.