G310.7–5.4 is a supernova remnant (SNR) candidate that was first identified as a faint shell in the Molonglo Galactic Plane Survey (MGPS-2), but which had not previously been followed up with multi-wavelength observations. It is an example of an SNR at a high Galactic latitude showing spatially coincident gamma-ray emission. Burger-Scheidlin et al. present the first detailed investigation of the radio emission from the G310.7–5.4 region, characterising the radio structure, polarisation measurements and the coincident GeV emission. The team used recent ASKAP EMU and POSSUM observations at 943.5 MHz, as well as 16.5 years of Fermi–LAT observations. They also considered the multiwavelength context of the object by investigating observations previously conducted with other instruments, such as infrared and X-ray surveys.

The team confirm the SNR candidate as a new supernova remnant, which they dub Abeona. (Abeona, the goddess of outward journeys in Roman mythology, protected travellers on their departing paths. This SNR, its progenitor having wandered off the Galactic plane and into the Galactic halo, therefore carries her name.) The ASKAP observations reveal the presence of a faint, extended, bilateral radio shell 30 arcminutes in diameter with no obvious infrared counterparts. The northern part of the shell shows linearly polarised radio emission, characteristic of synchrotron emission in SNRs. The SNR is spatially coincident with the Fermi gamma-ray source 4FGL J1413.9–6705 and the team put this source in context with known high-latitude SNRs with gamma-ray counterparts and compare with their observational properties. More sensitive observations with the Cherenkov Telescope Array Observatory (CTAO) in the next few years should provide valuable insights into particle acceleration and escape in these important cosmic ray accelerators. The image above shows the ASKAP 943.5 MHz total intensity image of Abeona. The synthesised beam of 15 arcseconds is represented with a small black circle in the bottom-left corner.