Mid-Infrared Outbursts in Nearby Galaxies: Nuclear Obscuration and Connections to Hidden Tidal Disruption Events and Changing-Look Active Galactic Nuclei

Abstract

We study the properties of galaxies hosting mid-infrared outbursts in the context of a catalog of five hundred thousand galaxies from the Sloan Digital Sky Survey. We find that nuclear obscuration, as inferred by the surrounding dust mass, does not correlate with host galaxy type, stellar properties (e.g. total mass and mean age), or with the extinction of the host galaxy as estimated by the Balmer decrement. This implies that nuclear obscuration may not be able to explain any over-representation of tidal disruption events in particular host galaxies. We identify a region in the galaxy catalog parameter space that contains all unobscured tidal disruption events but only harbors $\lesssim$ 11\% of the mid-infrared outburst hosts. We find that mid-infrared outburst hosts appear more centrally concentrated and have higher galaxy Sérsic indices than galaxies hosting active galactic nuclei (AGN) selected using the BPT classification. We thus conclude that the majority of mid-infrared outbursts are not hidden tidal disruption events but are instead consistent with being obscured AGN that are highly variable, such as changing-look AGN.

17 pages, 9 figures, accepted in ApJ Letters

References in corpus (28)

• The Host Galaxies and Classification of Active Galactic Nuclei
• Mass and environment as drivers of galaxy evolution in SDSS and zCOSMOS and the origin of the Schechter function
• The Co-Evolution of Galaxies and Supermassive Black Holes: Insights from Surveys of the Contemporary Universe
• The close environments of accreting massive black holes are shaped by radiative feedback
• The Mean Star Formation Rate of X-ray selected Active Galaxies and its Evolution from z=2.5: Results from PEP-Herschel
• The Final Season Reimagined: 30 Tidal Disruption Events from the ZTF-I Survey
• Broad-line Balmer Decrements in Blue Active Galactic Nuclei
• Image Decomposition of Barred Galaxies and AGN Hosts
• The Infrared Nuclear Emission of Seyfert Galaxies on Parsec Scales: Testing the Clumpy Torus models
• On the mass and luminosity functions of tidal disruption flares: rate suppression due to black hole event horizons
• The Host Galaxies of Tidal Disruption Events
• Understanding extreme quasar optical variability with CRTS: I. Major AGN flares
• Tidal Disruption Event Host Galaxies in the Context of the Local Galaxy Population
• TDE Hosts are Green and Centrally Concentrated: Signatures of a Post-Merger System
• The resolved size and structure of hot dust in the immediate vicinity of AGN
• Mid-InfraRed Outburst in Nearby Galaxies (MIRONG) I: Sample Selection and Characterization
• The Post-Starburst Evolution of Tidal Disruption Event Host Galaxies
• Contribution of Stellar Tidal Disruptions to the X-Ray Luminosity Function of Active Galaxies
• Rapid "Turn-on" of type 1 AGN in a quiescent early type galaxy SDSS1115+0544
• How does the Polar Dust affect the Correlation between Dust Covering Factor and Eddington Ratio in Type 1 Quasars Selected from the Sloan Digital Sky Survey Data Release 16?
• Stellar tidal disruption candidates found by cross-correlating the ROSAT Bright Source Catalogue and XMM-Newton observations
• The Landscape of Galaxies Harboring Changing-Look Active Galactic Nuclei in the Local Universe
• The AGN nature of 11 out of 12 Swift/RXTE unidentified sources through optical and X-ray spectroscopy
• Torus and polar dust dependence on AGN properties
• Mid-InfraRed Outbursts in Nearby Galaxies (MIRONG). II. Optical Spectroscopic Follow-up
• Forward Modeling Populations of Flares from Tidal Disruptions of Stars by Super-massive Black Holes
• The SAMI Galaxy Survey: Kinematics of stars and gas in brightest group galaxies; the role of group dynamics
• The variability of the broad-line Balmer decrement for quasars from the Sloan Digital Sky Survey Reverberation Mapping

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