Detecting γ-rays from the Ancora supernova remnant

Recently, a new supernova remnant (SNR), G288.8-6.3, was discovered at radio wavelengths as a faint shell with the Australian Square Kilometre Array Pathfinder (ASKAP) in the Evolutionary Map of the Universe (EMU) survey. This prompted a detailed investigation of γ-rays from the region that we would like to describe here. For this task, fifteen years of Fermi-Large Area Telescope (LAT) data were analysed between 400 MeV and 1 TeV. We detected spatially extended γ-ray emission overlapping with the radio SNR with a detection significance of up to 8.8 σ. The favoured model was a disk spatial model combined with a power-law spectral model, yielding an energy flux of (4.80±0.91)×10⁻⁶ MeV cm⁻² s⁻¹, with the spectrum extending up to 5 GeV. Given the estimates for the gas density, age and distance, the emission is more likely to be of leptonic origin.