MUSE observations of a changing-look AGN – I. The reappearance of the broad emission lines
AffiliationUniv Arizona, Steward Observ
galaxies: individual: Mrk 590
galaxies: kinematics and dynamics
MetadataShow full item record
PublisherOXFORD UNIV PRESS
CitationS I Raimundo, M Vestergaard, J Y Koay, D Lawther, V Casasola, B M Peterson, MUSE observations of a changing-look AGN – I. The reappearance of the broad emission lines, Monthly Notices of the Royal Astronomical Society, Volume 486, Issue 1, June 2019, Pages 123–140, https://doi.org/10.1093/mnras/stz852
Rights© 2019 The Author(s) Published by Oxford University Press on behalf of the Royal Astronomical Society
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AbstractOptical changing-look Active Galactic Nuclei (AGN) are a class of sources that change type within a short time-scale of years or decades. This change is characterized by the appearance or disappearance of broad emission lines, often associated with dramatic AGN continuum flux changes that are orders of magnitude larger than those expected from typical AGN variability. In this work we study for the first time the host galaxy of a changing-look AGN, Mrk 590, using high spatial resolution optical and near-infrared observations. We discover that after similar to 10 yr absence, the optical broad emission lines of Mrk 590 have reappeared. The AGN optical continuum flux however is still similar to 10 times lower than that observed during the most luminous state in the 1990s. The host galaxy shows a 4.5 kpc radius star-forming ring with knots of ionized and cold molecular gas emission. Extended ionized and warm molecular gas emission is detected in the nucleus, indicating that there is a reservoir of gas as close as 60 pc from the black hole. We observe a nuclear gas spiral between radii r similar to 0.5 and 2 kpc, which has been suggested as a dynamical mechanism able to drive the necessary gas to fuel AGN. We also discover blue-shifted and high velocity dispersion [O III] emission out to a radius of 1 kpc, tracing a nuclear gas outflow. The gas dynamics in Mrk 590 suggest a complex balance between gas inflow and outflow in the nucleus of the galaxy.
VersionFinal published version
SponsorsIndependent Research Fund Denmark [DFF-4002-00275]; European Organisation for Astronomical Research in the Southern Hemisphere under ESO programmes [080.B-0239, 099.B-0294(A)]; Brazilian agency CNPq; Brazilian agency CAPES; Brazilian agency FAPESP; France-Brazil CAPES/Cofecub program
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