Prospects for the detection of Dark Matter with Long-lived Mediators in the Sun using the Southern Wide-field Gamma-ray Observatory

TL;DR

This paper evaluates SWGO's potential to detect gamma-ray signals from dark matter annihilations in the Sun via long-lived mediators, showing it could significantly improve current detection sensitivity.

Contribution

It introduces a novel analysis of SWGO's sensitivity to dark matter via long-lived mediators in the Sun, surpassing existing experimental limits.

Findings

SWGO can probe spin-dependent cross-sections down to 10^{-46} cm^2 for dark matter masses under 5 TeV.

SWGO's sensitivity exceeds current instruments by over an order of magnitude.

Detection of gamma-ray signatures from metastable mediators is feasible with SWGO.

Abstract

The operation of the next generation of gamma-ray observatories will lead to a great advance in dark matter searches. In this paper, we use the hidden sectors hypothesis within the so-called secluded models to calculate the capabilities of the Southern Wide-field Gamma-ray Observatory (SWGO) to detect gamma-ray signatures produced by dark matter particles concentrated in the Sun. We assume the dark matter particle annihilates into metastable mediators which decay into $\gamma\gamma$, $e^+e^-$, $\tau^+\tau^-$, and $\bar{b}b$ outside the Sun. We found that the SWGO will be able to probe a spin-dependent cross-section of about $10^{-46}$ cm$^2$ for dark matter masses smaller than 5 TeV. This result shows an unprecedented sensitivity surpassing the current instruments by more than one order of magnitude.