Illuminating Very Heavy Dark Matter in the Earth with Tau Neutrinos

TL;DR

This paper shows that neutrino telescopes like IceCube can detect very heavy dark matter particles annihilating into tau neutrinos, setting new limits on dark matter properties for masses up to 10^10 GeV.

Contribution

It demonstrates the potential of high-energy neutrino telescopes to probe extremely heavy dark matter particles through tau neutrino signals, extending previous mass limits.

Findings

Set upper limits on dark matter-nucleon cross section for masses 10^5 to 10^10 GeV.

Showed neutrino telescopes can detect very heavy dark matter via tau neutrinos.

Motivated further analyses in IceCube and other neutrino observatories.

Abstract

Dark matter accumulates in the center of the Earth as the planet plows through the dark matter halo in the Milky Way. Possible annihilation of dark matter to Standard Model particles can be probed in indirect dark matter searches. Among possible messengers, neutrinos are uniquely ideal as they can escape dense regions. Therefore, neutrino telescopes, with their large volume and broad energy exposures, offer new opportunities to search for dark matter signals from the center of the Earth. However, such studies have been restricted to dark matter masses below $\sim$ PeV as the Earth becomes opaque to very-high-energy neutrinos. In this study, we demonstrate that neutrino telescopes operating at TeV-PeV energies can probe very heavy dark matter particles if they annihilate to tau neutrinos or tau leptons. Here, we report upper limits on the spin-independent dark matter-nucleon cross section for masses between $10^5$ GeV and $10^{10}$ GeV by using 7.5 years of IceCube high-energy starting event observations. Our results motivate detailed analyses in IceCube and other upcoming neutrino telescopes in the Northern Hemisphere.