Coffee talks
Friday 05/11/2021 @ 11:30, On-line - meet.google.com/sue-bwvk-axf
Vijay Mahatma (Thüringer Landessternwarte), "Imaging with the LOFAR international stations: bright radio galaxies and their polarized properties"
In the past, sub-arcsecond imaging of bright radio galaxies have revealed a plethora of components in the hotspots, lobes and jets. Moreover, their polarized emission has revealed many details about the dynamics of jet-IGM and jet-lobe interactions that have shaped our understanding of radio galaxies today. However, such imaging has exclusively been performed at GHz frequencies, where the polarized emission is stronger than at lower frequencies, but the observed emission is affected by spectral ageing. Sensitive sub-arcsecond imaging of bright nearby radio galaxies at MHz frequencies is missing, while little is known about their polarization behaviour in this regime. Here, I present an on-going study of the radio galaxies 3C263 and 3C34, using data from the LOFAR Two-Metre Sky Survey at 150 MHz. Using the international baselines, I present the first sub-arcsecond images in total intensity and in polarization. I discuss what we can learn from such exclusive imaging, and how our understanding of radio galaxies can improve in the context of future high resolution imaging.