Landing page for project ES106

Recent optical and mid-infrared time-domain surveys have led to the discovery of a rare but extremely interesting class transients dubbed as "turn-on" AGNs, which have changed from quasi-quiescent galaxies/LINERs to broad-line AGNs within only months to years. Such a rapid state transformation with dramatic changes in accretion rate provides the unique laboratory to explore the ignition mechanism of accretion onto supermassive black holes, and possibly the mystery of jet formation in AGNs. Despite extensive searches, only few bona fide "turn-on" AGNs have been reported so far. We have used GMRT/VLA/EVN to follow-up a candidate "turn-on" AGN, and found unusual radio flux and spectral evolution, characterized by more than one synchrotron emission components. EVN observations have only marginally resolved the radio emission at mas scales. We request new EVN observations at the same bands as previous ones performed about 2 years ago, with the immediate aim to constrain the superluminal motion velocity of jet or its upper limit, as well as the radio spectral evolution at mas scales. The observing results will provide a new benchmark for future high-resolution studies of radio transients of this kind.

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