Search for muon signal from dark matter annihilations in the Sun with the Baksan Underground Scintillator Telescope for 24.12 years

TL;DR

This study analyzes 24.12 years of neutrino data from the Baksan Telescope to search for dark matter signals from the Sun, setting new upper limits on neutrino fluxes and dark matter interaction cross sections.

Contribution

It provides the longest dataset analysis for dark matter searches with an improved methodology and new upper limits on neutrino fluxes from dark matter annihilations in the Sun.

Findings

No excess muons detected above background.

Set 90% confidence level upper limits on neutrino fluxes.

Derived constraints on dark matter-proton scattering cross sections.

Abstract

We present a new dataset analysis of the neutrino experiment at the Baksan Underground Scintillator Telescope with muon energy threshold about 1 GeV for the longest exposure time toward the Sun. In search for a signal from self-annihilations of dark matter particles in the center of the Sun we use an updated sample of upward through-going muons for 24.12 years of live time. No observable excess has been found in measured muons relative to expected background from neutrinos of atmospheric origin. We present an improved data analysis procedure and describe it in detail. We set the 90\% C.L. new upper limits on expected neutrino and muon fluxes from dark matter annihilations in the Sun, on the corresponding annihilation rates and cross sections of their elastic scattering off proton.