Speaker
Giacomo Cannizzaro
(Radboud University Nijmegen)
Description
CSS100217 was a nuclear flare in a Seyfert 1 galaxy, whose initial interpretation as a nuclear supernova is now debated between a tidal disruption event (TDE) and a flare from the active galactic nucleus (AGN). We discuss new evidence in favour of a TDE interpretation, mainly the marked difference in the optical quiescent flux before and after the outburst, as the post-outburst flux level is 0.4 mag fainter than before. The host galaxy of CSS100217 appears as a point source and is smaller and more compact than AGN host galaxies at comparable redshift. CSS100217 is not only a one-of-a-kind transient, it appears to lie in a one-of-a-kind host galaxy.
