Using strong lensing to understand the microJy radio emission in two radio quiet quasars at redshift 1.7

ABSTRACT The radio quasar luminosity function exhibits an upturn around $L_{6\rm \:GHz}=10^{23}$ W Hz−1 that is well-modelled by a star-forming host galaxy population. This distribution leads some authors to cite star formation as the main emission mechanism in so-called radio-quiet quasars (RQQs). Understanding origin of RQQ crucial for our understanding feedback mechanisms – responsible regulation and evolution whole. By observing RQQs have been magnified strong gravitational lensing, we direct access population out cosmic noon, where evidence twin mini-jets has recently found sub-$\mu$Jy RQQ. Here present observations two lensed using VLA at 5 GHz, latest objects be observed sample quadruply-imaged above −30°. In SDSS J1004+4112 find AGN-related variability source. PG 1115+080 tentative emission, determined comparing with modelled dust components. If confirmed case 1115+080, which lies on radio–FIR correlation, result would reinforce need caution when applying correlation rule jet activity assuming no AGN heating FIR-emitting calculating rates. Our programme so far shown faintest sources ever imaged show AGN-dominated emission.