AGN on the Beach

RQ AGN and evolutionary studies

The Quasar Feedback Survey; zooming into the core of radio emission

Ann Njeri

 Fr, 9:30 ! Livein  Palazzo Santa Chiarafor  15min

Understanding how quasars feedback'' on their host galaxies remains a significant challenge of galaxy formation theory. Observations have connected the prevalence of galaxy-wide ionised outflows to the level of radio emission and, consequently, show that understanding the origin of radio emission in typical quasar host galaxies is a key piece of thefeedback’’ puzzle. Towards addressing this, we are performing a systematic study of a representative sample of 71 quasars at z < 0.2 (LAGN ≳10^45 erg/s). Whilst VLA data have revealed that two thirds of the sample show jet/lobe structures on > ~kpc scales, the data are not sensitive to morphologies on smaller scales and show that majority of the radio emission is located in featureless/unresolved nuclear regions. Therefore, the origin of the significant radio emission remains unknown, resulting in missing critical insight into the quasar-host galaxy connection. Using e-MERLIN imaging at C-band, I will show how we are disentangling the different radio production mechanisms at sub-kpc scales. Combining e-MERLIN data with VLA data, we have determined the primary outflow driving mechanisms, and assessed the dominant source of radio emission, across physical scales of ~100pc to ~10kpc.

 Overview  Program