New constraints on radiative seesaw models from IceCube and other neutrino detectors

TL;DR

This paper evaluates the potential of neutrino detectors like IceCube to detect dark matter in radiative seesaw models, showing that fermion dark matter could produce detectable signals, while scalar dark matter likely cannot.

Contribution

It provides the first detailed calculation of neutrino event rates for scalar and fermion dark matter in a radiative seesaw model, linking indirect detection prospects with direct detection constraints.

Findings

Fermion dark matter can produce detectable neutrino signals at IceCube.

Scalar dark matter yields very low neutrino event rates, below current detection thresholds.

XENON1T limits exclude parts of the parameter space accessible to IceCube.

Abstract

Dark matter (DM) scattering and its subsequent capture in the Sun can boost the local relic density, leading to an enhanced neutrino flux from DM annihilations that is in principle detectable at neutrino telescopes. We calculate the event rates expected for a radiative seesaw model containing both scalar triplet and singlet-doublet fermion DM candidates. In the case of scalar DM, the absence of a spin dependent scattering on nuclei results in a low capture rate in the Sun, which is reflected in an event rate of less than one per year in the current IceCube configuration with 86 strings. For singlet-doublet fermion DM, there is a spin dependent scattering process next to the spin independent one, which significantly boosts the event rate and thus makes indirect detection competitive with respect to the direct detection limits imposed by PICO-60. Due to a correlation between both scattering processes, the limits on the spin independent cross section set by XENON1T exclude also parts of the parameter space that can be probed at IceCube. Previously obtained limits by ANTARES, IceCube and Super-Kamiokande from the Sun and the Galactic Center are shown to be much weaker.