Landing page for project EY044

Tidal disruption events (TDEs) might cause a transient super Eddington accretion, power some strongly delayed radio flares during later low accretion state, and even form some short-lived low-luminosity radio AGNs. The Gaia transient AT2018cqh in the nearby (z=0.048) dwarf AGN J023346.8-010128.3 has recently been associated with a TDE by multi-epoch X-ray sky surveys. Furthermore, there is a very luminous radio flare detected 2--5 years after the TDE. The radio transient brightened rapidly and reached 10.7 mJy at 5 GHz on 2024 Jan 16. The rapid brightening, very high luminosity and long delay indicate that there might be a (mildly) relativistic jet launched in a previously radio-quiescent dwarf AGN. Here, we request four-epoch VLBI observations of the nearby TDE AT2018cqh to search for such an unprecedented jet. Using two nearby new calibrators identified in the pilot short observations RSY11, we expect to significantly detect a motion with a transverse jet speed of >=0.1c over two years. The detection would enable us to reveal a strongly delayed jet activity from a thermal TDE, characterise jet parameters, and strengthen the connection between AGN jet activity and thermal TDEs.

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