Deep radio characterization of the supernova remnant G343.1-00.7

Supernova remnants (SNRs) are extended radio sources whose morphology and evolution are shaped by the interaction of strong shocks with the surrounding medium. Radio morphological and spectral studies are essential for investigating their local physical properties and particle acceleration mechanisms. We conducted a detailed radio morphological analysis of the SNR G343.1-00.7 and accurately determined its radio continuum spectral properties, both integrated and spatially resolved. We combined the 0.944 GHz Australian Square Kilometre Array Pathfinder (ASKAP) image from the Evolutionary Map of the Universe (EMU) survey with 0.088–0.200 GHz MWA-GLEAM data to characterize the integrated radio spectrum of G343.1-00.7 and perform its first sensitive spatially resolved spectral analysis. We derive an integrated spectral index of α=-0.50 for G343.1-00.7, confirming the previously reported value with significantly improved accuracy. We redefine the radio morphology of the remnant, providing the first morphological and spectral evidence that the filamentary structures overlapping the nearby G343.147-00.44 are physically associated with the SNR. Local brightness-brightness analysis further reveals flatter-spectrum filaments along the southeastern shell, consistent with a possible thermal bremsstrahlung contribution from radiative or partially radiative shocks. By comparison with and CO data, we identify atomic and molecular gas components kinematically consistent with the SNR distance, although no clear morphological evidence of interaction is found. The gas distribution around the however, suggests the presence of an expanding shell partially embedded within its parent molecular cloud. Overall, theoretical models based on our radio characterization place G343.1-00.7 between the late Sedov phase and the early pressure-driven phase of its evolution, suggesting that different regions may be at different evolutionary stages. Our results demonstrate the potential of high-resolution ASKAP observations for characterizing the morphology and spatially resolved spectral properties of SNRs, particularly for poorly studied remnants in complex Galactic environments.