Accretion and star formation in 'radio-quiet' quasars
  Radio observations allow us to identify a wide range of active galactic
nuclei (AGN), which play a significant role in the evolution of galaxies.
Amongst AGN at low radio-luminosities is the 'radio-quiet' quasar (RQQ)
population, but how they contribute to the total radio emission is under
debate, with previous studies arguing that it is predominantly through star
formation. In this talk, SVW summarised the results of recent papers on RQQs,
including the use of far-infrared data to disentangle the radio emission from
the AGN and that from star formation. This provides evidence that black-hole
accretion, instead, dominates the radio emission in RQQs. In addition, we find
that this accretion-related emission is correlated with the optical luminosity
of the quasar, whilst a weaker luminosity-dependence is evident for the radio
emission connected with star formation. What remains unclear is the process by
which this accretion-related emission is produced. Understanding this for RQQs
will then allow us to investigate how this type of AGN influences its
surroundings. Such studies have important implications for modelling AGN
feedback, and for determining the accretion and star-formation histories of the
Universe.
