2018MNRAS.474..102A

We report the discovery of a ∼3^○^///.4-wide region of high-energy emission in data from the Fermi LAT satellite. The centroid of the emission is located in the Southern hemisphere sky, a few degrees away from the plane of the Galaxy at the Galactic coordinates l = 350^○^///.6, b = -4^○^///.7. It shows a hard spectrum that is compatible with a simple power law, d/N dE∝E^-Γ^, in the energy range 0.7-500 GeV, with a spectral index Γ = 1.68 ± 0.04_stat ± 0.1_sys. The integrated source photon flux above 0.7 GeV is (4.71 ± 0.49_stat ± 2.13_sys) x 10^–9 cm^–2 s^–1. We discuss several hypotheses for the nature of the source, particularly that the emission comes from the shell of an unknown supernova remnant.