DOI

https://doi.org/10.48717/6jpz-m070

Project

EH035

Title

First-epoch VLBI of PG1115

Abstract

Strong gravitational lensing can be used to observe otherwise undetectable background sources, thanks to the magnifying power of the lensing mass. We have used this property to study radio quiet quasars (RQQs), which produce radio emission at the microJy level; orders of magnitude lower than their radio loud counterparts. It is unknown whether the emission mechanism operating in these seemingly distinct populations is the same AGN one, or whether RQQs represent quasars at a different stage of evolution, with radio emission resulting instead from starburst activity. Until recently, evidence had relied on statistical studies subject to associated biases. However, the combination of strong lensing with the very high resolution and sensitivity of the EVN has allowed us to directly image one RQQ, finding firm evidence for AGN jet/core activity. We propose the observation of another strongly lensed RQQ in order to extend our findings concerning these intriguing objects. A non-detection would provide a robust rejection of the unified AGN hypothesis in this case.