Enhanced Sensitivity to Dark Matter Self-annihilations in the Sun using Neutrino Spectral Information

TL;DR

This paper presents a method to improve detection of dark matter annihilation signals in the Sun using neutrino spectral information, enhancing sensitivity especially for low-mass WIMPs in neutrino telescopes.

Contribution

It introduces a novel spectral analysis technique to convert neutrino flux constraints into limits on WIMP-nucleon scattering, applicable to all neutrino flavors.

Findings

High sensitivity achieved for low-mass WIMPs.

Electron neutrino channel provides the best results.

Method accounts for uncertainties in the analysis.

Abstract

Self-annihilating dark matter gravitationally captured by the Sun could yield observable neutrino signals at current and next generation neutrino detectors. By exploiting such signals, neutrino detectors can probe the spin-dependent scattering of weakly interacting massive particles (WIMPs) with nucleons in the Sun. We describe a method how to convert constraints on neutrino fluxes to a limit on the WIMP-nucleon scattering cross section. In this method all neutrino flavors can be treated in a very similar way. We study the sensitivity of neutrino telescopes for Solar WIMP signals using vertex contained events and find that this detection channel is of particular importance in the search for low mass WIMPs. We obtain highly competitive sensitivities with all neutrino flavor channels for a Megaton sized detector through the application of basic spectral selection criteria. Best results are obtained with the electron neutrino channel. We discuss associated uncertainties and provide a procedure how to treat them for analyses in a consistent way.