Oral Presentation

Gas fueling and extreme variability in the changing-look AGN Mrk 590

Author(s): Jun Yi Koay (ASIAA), Marianne Vestergaard (DARK), Hayley Bignall (CSIRO), Viviana Casasola (INAF), Daniel Lawther (DARK), Bradley Peterson (OSU/STSI), Cormac Reynolds (CSIRO)

Presenter: Jun Yi Koay (ASIAA)

The supermassive black hole in the Seyfert galaxy Mrk 590 was accreting mass at a high rate of ~10% of the Eddington limit in the 1990s, but within a span of 10 years has dramatically shut down. Such extreme behavior in this changing-look AGN provides an excellent opportunity to study the physics of supermassive black hole fueling and gas accretion. I present the first ALMA observations of the CO(3-2) and CO(1-0) emission lines in Mrk 590 to examine if this AGN is running out of gas, and to investigate its gas fueling mechanisms. I will also present ongoing efforts to monitor the changing SED of the central continuum emission with ALMA and other telescopes at radio to X-ray wavelengths, to determine the cause of the significant changes in accretion rate. Issues and challenges affecting time-domain studies using ALMA will be discussed.