Detecting electron neutrinos from solar dark matter annihilation by JUNO

TL;DR

This paper investigates JUNO's potential to detect electron neutrinos from solar dark matter annihilation, showing it could surpass current detection limits and clarify existing experimental tensions.

Contribution

It introduces a method to evaluate JUNO's sensitivity to dark matter signals from the Sun across different annihilation channels, highlighting its superior potential over existing experiments.

Findings

JUNO can significantly improve sensitivity to spin-dependent DM-proton cross sections.

JUNO outperforms current limits for light DM masses in certain channels.

Results can help resolve discrepancies between DAMA and other direct detection experiments.

Abstract

We explore the electron neutrino signals from light dark matter (DM) annihilation in the Sun for the large liquid scintillator detector JUNO. In terms of the spectrum features of three typical DM annihilation channels $\chi \chi \rightarrow \nu \bar{\nu},\tau^+ \tau^-, b \bar{b}$, we take two sets of selection conditions to calculate the expected signals and atmospheric neutrino backgrounds based on the Monte Carlo simulation data. Then the JUNO sensitivities to the spin independent DM-nucleon and spin dependent DM-proton cross sections are presented. It is found that the JUNO projected sensitivities are much better than the current spin dependent direct detection experimental limits for the $\nu \bar{\nu}$ and $\tau^+ \tau^-$ channels. In the spin independent case, the JUNO will give the better sensitivity to the DM-nucleon cross section than the LUX and CDMSlite limits for the $\nu \bar{\nu}$ channel with the DM mass lighter than 6.5 GeV. If the $\nu \bar{\nu}$ or $\tau^+ \tau^-$ channel is dominant, the future JUNO results are very helpful for us to understand the tension between the DAMA annual modulation signal and other direct detection exclusions.