Description
Based on all-sky, low-resolution radio surveys, the nature and origin of radio emission in radio quiet quasars remains typically ambiguous. Using e-MERLIN, we investigated radio emission on sub-kiloparsec scales (∼10s–100s pc) for 42 z < 0.2 type 1 and type 2 mostly radio-quiet quasars (L$_{[O III]} >10^{42}$ erg s$^{−1}$; L$_\mathrm{AGN} >10^{45}$ erg s−1) in the Quasar Feedback Survey. 37/42 quasars were detected with eMERLIN and showed diverse radio morphologies with sizes of 30–540 pc, including weak unresolved cores, well defined hotspots/knots, sub-kiloparsec radio jets, side lobes and irregular diffuse features, often missed by lower-resolution (~kpc scales) VLA imaging. Based on morphology and brightness temperature, we classified 76 per cent of the quasars as radio-AGN, compared to the ∼57 per cent identified as radio-AGN at the ∼1–60 kpc scales probed in prior studies. We found no significant differences in measured radio properties between type 1 and type 2 quasars. These quasars also share characteristics with compact radio populations, suggesting that the global radio emission is likely tracing strong interactions between the AGN (jets/outflows) and their host galaxy ISM from 10s parsec to 10s kiloparsec scales. I will present our findings (tracing sub-kiloparsec scales through to 10s of kiloparsec scales), with additional new 29 radio-quiet quasars (L$_{1.4}<10^{22.5}$ W Hz s−1) recently obtained with VLA at 1.4 and 6 GHz, and show how this is transforming our understanding of AGN feedback mechanisms at sub-galactic scales and the importance of sensitive radio imaging, down to sub-kiloparsec scales provided by eMERLIN.
