Probing annihilations and decays of low-mass galactic dark matter in IceCube DeepCore array: Track events

TL;DR

This paper calculates the sensitivity of the IceCube DeepCore array to low-mass galactic dark matter annihilations and decays by analyzing track events at a lowered energy threshold of 10 GeV, improving detection prospects.

Contribution

It introduces a new approach by lowering the energy threshold to 10 GeV for better sensitivity to low-mass dark matter signals in IceCube DeepCore.

Findings

Lowered energy threshold enhances dark matter detection sensitivity.

Sensitivity is significantly improved for dark matter masses below 100 GeV (annihilation) and 300 GeV (decay).

Comparison shows better performance than previous threshold-based estimates.

Abstract

The deployment of DeepCore array significantly lowers IceCube's energy threshold to about 10 GeV and enhances the sensitivity of detecting neutrinos from annihilations and decays of light dark matter. To match this experimental development, we calculate the track event rate in DeepCore array due to neutrino flux produced by annihilations and decays of galactic dark matter. We also calculate the background event rate due to atmospheric neutrino flux for evaluating the sensitivity of DeepCore array to galactic dark matter signatures. Unlike previous approaches, which set the energy threshold for track events at around 50 GeV (this choice avoids the necessity of including oscillation effect in the estimation of atmospheric background event rate), we have set the energy threshold at 10 GeV to take the full advantage of DeepCore array. We compare our calculated sensitivity with those obtained by setting the threshold energy at 50 GeV. We conclude that our proposed threshold energy significantly improves the sensitivity of DeepCore array to the dark matter signature for $m_{\chi}< 100$ GeV in the annihilation scenario and $m_{\chi}<300$ GeV in the decay scenario.