Landing page for project EZ040

The Gaia transient AT2018cqh has recently been identified as a rarely seen tidal disruption event (TDE) in the nearby (~200 Mpc) dwarf AGN J023346.8-010128.3. It exhibited an unusually delayed yet luminous radio flare 2--5 years after the optical flare. The radio transient brightened ?20 times over ?2.5 years in the multiepoch VLA Sky Survey. Our two EVN observations at 5 GHz detected a compact source (?0.1 mas) with increasing flux density (~15 mJy on 2024 Oct 27). We measured a tentative proper motion of 1.0±0.6c. The long delay and rapid brightening indicate that there might be a mildly relativistic, off-axis jetted outflow launched by its intermediate-mass black hole (IMBH). Here, we request one follow-up VLBI observation of AT2018cqh to constrain its proper motion and expansion speed. Combined with our existing high-precision astrometry observations, we can significantly detect a proper motion of ?0.25 c within 2 year for AT2018cqh.

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