The ambiguous AT2022rze: changing-look AGN mimicking a supernova in a merging galaxy system

ABSTRACT AT2022rze is a luminous, ambiguous transient located south-east of the geometric centre of its host galaxy at redshift $z = 0.08$. The host appears to be formed by a merging galaxy system. The observed characteristics of AT2022rze are reminiscent of active galactic nuclei (AGNs), tidal disruption events, and superluminous supernovae. The transient reached a peak absolute magnitude of $-$20.2 $\pm$ 0.2 mag, showing a sharp rise (t$_{\mathrm{rise,1/e}} = 27.5 \pm 0.6$ d) followed by a slow decline (t$_{\mathrm{dec,1/e}} = 382.9 \pm 0.6$). Its bumpy light curve and narrow Balmer lines indicate the presence of gas (and dust). Its light curve shows rather red colours, indicating that the transient could be affected by significant host extinction. The spectra reveal coronal lines, indicative of high-energy (X-ray/UV) emission. Archival data reveal no prior activity at this location, disfavouring a steady-state AGN, although an optical spectrum obtained prior to the transient is consistent with an AGN classification of the host. Based on this, we conclude that the transient most likely represents a changing-look AGN at the centre of the smallest component of the merging system.

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Publication Details

Journal
Monthly Notices of the Royal Astronomical Society
Published
2025-08-28
DOI
https://doi.org/10.1093/mnras/staf1433
Citations
3
Primary Topic
Astronomy and Astrophysical Research
Type
article
Field-Weighted Citation Impact
3.58

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article

The ambiguous AT2022rze: changing-look AGN mimicking a supernova in a merging galaxy system

Yu-Jing Qin, Matthew Hayes, Sherri Rose, S. Brennan et al.
3 citations
Monthly Notices of the Royal Astronomical Society
Astronomy and Astrophysical Research
3.58
article

The ambiguous AT2022rze: changing-look AGN mimicking a supernova in a merging galaxy system

Yu-Jing Qin, Matthew Hayes, Sherri Rose, S. Brennan, P. J. Pessi, T. Nagao, Adam A. Miller, Kishalay De, I. Pérez‐Fournon, Yuhan Yao, K. R. W. Tristram, M. J. Graham, M. Gilfanov, C Fransson, P. Charalampopoulos, Frank J. Masci, S. Mattila, Josiah Purdum, K-Ryan Hinds, Tao Chen, C. Fremling, Lin Yan, J. S. Bloom, Steve Schulze, R. Sunyaev, C. P. Gutiérrez, F. Poidevin, A. Gkini, J. Johansson, Anjasha Gangopadhyay, Chang Liu, M. M. Kasliwal, Joël Brugger, Y Sharma, Yang Hu, S. Nordblom
article en
3 citations

Abstract

ABSTRACT AT2022rze is a luminous, ambiguous transient located south-east of the geometric centre of its host galaxy at redshift $z = 0.08$. The host appears to be formed by a merging galaxy system. The observed characteristics of AT2022rze are reminiscent of active galactic nuclei (AGNs), tidal disruption events, and superluminous supernovae. The transient reached a peak absolute magnitude of $-$20.2 $\pm$ 0.2 mag, showing a sharp rise (t$_{\mathrm{rise,1/e}} = 27.5 \pm 0.6$ d) followed by a slow decline (t$_{\mathrm{dec,1/e}} = 382.9 \pm 0.6$). Its bumpy light curve and narrow Balmer lines indicate the presence of gas (and dust). Its light curve shows rather red colours, indicating that the transient could be affected by significant host extinction. The spectra reveal coronal lines, indicative of high-energy (X-ray/UV) emission. Archival data reveal no prior activity at this location, disfavouring a steady-state AGN, although an optical spectrum obtained prior to the transient is consistent with an AGN classification of the host. Based on this, we conclude that the transient most likely represents a changing-look AGN at the centre of the smallest component of the merging system.

Monthly Notices of the Royal Astronomical SocietyVol. 542(4)
Northwestern University (US), California Institute of Technology (US), Sherman Hospital (US), University of Minnesota (US), Institute of Space Sciences (ES), Lawrence Berkeley National Laboratory (US), University of Turku (FI), Universidad de La Laguna (ES), Stockholm University (SE), European University Cyprus (CY), Chestnut Hill College (US), Space Research Institute (RU), Miller College (US), Institut d'Estudis Espacials de Catalunya (ES), Kavli Institute for Particle Astrophysics and Cosmology (US), Max Planck Institute for Astrophysics (DE), Simons Foundation (US), European Southern Observatory (CL), Instituto de Astrofísica de Canarias (ES), AlbaNova (SE), Infrared Processing and Analysis Center (US), Liverpool John Moores University (GB), University of California, Berkeley (US), Universitat Politècnica de Catalunya (ES), Aalto University (FI)
National Science Foundation, National Aeronautics and Space Administration, Gordon and Betty Moore Foundation, Research Corporation for Science Advancement, California Institute of Technology, Northwestern University, University of Washington, Space Telescope Science Institute, National Radio Astronomy Observatory, Associated Universities, University of Warwick, European Commission, Queen's University Belfast, Trinity College Dublin, Weizmann Institute of Science, Generalitat de Catalunya, Queen's University, Nuclear Safety and Security Commission, Ministerio de Ciencia e Innovación, Stockholms Universitet, Science and Technology Facilities Council, Deutsches Elektronen-Synchrotron, Agencia Estatal de Investigación, Institut National de Physique Nucléaire et de Physique des Particules
Openalex Percentile: Top 7%
Astronomy and Astrophysical Research
3.58
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