A novel way of constraining WIMPs annihilations in the Sun: MeV neutrinos

TL;DR

This paper explores a new method of constraining WIMP dark matter annihilations in the Sun by analyzing MeV neutrinos from decay processes, using Super-Kamiokande data to set limits on WIMP properties.

Contribution

It introduces the consideration of low-energy MeV neutrinos from decay at rest as a novel approach to constrain dark matter annihilation channels in the Sun.

Findings

Set new limits on WIMP-nucleon scattering cross sections.

Demonstrated the feasibility of using MeV neutrino data for dark matter constraints.

Provided a comprehensive analysis including WIMP evaporation rates.

Abstract

Annihilation of dark matter particles accumulated in the Sun would produce a flux of high-energy neutrinos whose prospects of detection in neutrino telescopes and detectors have been extensively discussed in the literature. However, for annihilations into Standard Model particles, there would also be a flux of neutrinos in the MeV range from the decays at rest of muons and positively charged pions. These low-energy neutrinos have never been considered before and they open the possibility to also constrain dark matter annihilation in the Sun into e+e-, mu+mu- or light quarks. Here we perform a detailed analysis using the recent Super-Kamiokande data in the few tens of MeV range to set limits on the WIMP-nucleon scattering cross section for different annihilation channels and computing the evaporation rate of WIMPs from the Sun for all values of the scattering cross section in a consistent way.