Sagittarius dwarf spheroidal galaxy observed by H.E.S.S

TL;DR

This paper reports on 90 hours of H.E.S.S. observations of the Sagittarius dwarf spheroidal galaxy, aiming to detect gamma-ray signals from dark matter annihilation and setting new constraints on dark matter particle properties.

Contribution

It provides the first extensive gamma-ray observational constraints on dark matter annihilation in the Sagittarius dwarf galaxy using H.E.S.S.

Findings

No significant gamma-ray signal detected

New upper limits on dark matter annihilation cross-section

Constraints applicable to Majorana WIMPs

Abstract

Dwarf spheroidal galaxies are characterized by a large measured mass-to-light ratio and are not expected to be the site of high-luminosity non-thermal high-energy gamma-ray emissions. Therefore they are among the most promising candidates for indirect searches of dark matter particle annihilation signals in gamma rays. The Sagittarius dwarf spheroidal galaxy has been regularly observed by the High Energy Stereoscopic System (H.E.S.S.) of Cherenkov telescopes for more than 90 hours, searching for TeV gamma-ray emission from annihilation of dark matter particles. In absence of a significant signal, new constraints on the annihilation crosssection of the dark matter particles applicable for Majorana Weakly Interacting Massive Particles (WIMPs) are derived.