New Sensitivity to Solar WIMP Annihilation using Low-Energy Neutrinos

TL;DR

This paper proposes using low-energy neutrinos from pion decay in the Sun to improve detection of WIMP annihilation, offering a new, competitive method for probing dark matter interactions.

Contribution

It introduces a novel approach to detect solar WIMP annihilation via low-energy neutrinos from pion decay, expanding current search strategies.

Findings

Super-Kamiokande can effectively detect low-energy neutrinos from WIMP annihilation.

The method provides competitive sensitivity to the WIMP-proton cross section.

Uncertainties in the new detection method are complementary to existing techniques.

Abstract

Dark matter particles captured by the Sun through scattering may annihilate and produce neutrinos, which escape. Current searches are for the few high-energy neutrinos produced in the prompt decays of some final states. We show that interactions in the solar medium lead to a large number of pions for nearly all final states. Positive pions and muons decay at rest, producing low-energy neutrinos with known spectra, including nuebar through neutrino mixing. We demonstrate that Super-Kamiokande can thereby provide a new probe of the spin-dependent WIMP-proton cross section. Compared to other methods, the sensitivity is competitive and the uncertainties are complementary.