Landing page for project EX010

Dual active galactic nuclei (dual AGN) provide unique insights into constraining the progenitors and early stages of galaxy mergers but remain scarce at high redshift. Recently, the 'Varstrometry' technique identified a sample of dual-quasar candidates at z>0.5 by measuring excess positional noise in Gaia data. VLA follow-up revealed multi-core structures in some of these candidates, but further confirmation still be required. Here we propose to observe two such candidates, J0111+1713 (z=2.198) and J0950+2635 (z=1.771), with the EVN+e-MERLIN at 1.6 GHz. Together with the existing VLBA observations at S and X bands, we aim to elucidate their pc-scale radio structures and spectral shapes to verify whether they are dual-core quasar systems, which may be responsible for their excess astrometric noises. In addition, the proposed deep VLBI observations at the lower frequency would help to reveal some faint extended emission associated with each radio core.

This data is part of the archive of VLBI data maintained by JIVE on behalf of the EVN, a network of radio telescopes located primarily in Europe and Asia, with additional antennas in South Africa. The EVN archive itself has the DOI https://doi.org/10.17616/R3Z197