A century of change: new changing-look event in Mrk 1018's past
Thomas Dunn, Rebecca McElroy, Mirko Krumpe, Scott M. Croom, Massimo Gaspari, Miguel Perez-Torres, Michael Cowley, Osase Omoruyi, Grant Tremblay, Mainak Singha

TL;DR
This study analyzes over a century of data on Mrk 1018, revealing a historic outburst and suggesting long-term accretion rate modulation as the cause of its changing-look behavior, with rapid recent transitions.
Contribution
It uncovers a historic outburst in Mrk 1018 and proposes a long-term modulation mechanism, advancing understanding of changing-look AGN variability.
Findings
Historic outburst between 1935-1960 with ~0.8 mag variation
Broad periodicity of 29-47 years suggested by Lomb-Scargle analysis
Recent turn-off duration constrained to less than 1.9 years
Abstract
We investigate the long-term variability of the known Changing Look Active Galactic Nuclei (CL AGN) Mrk 1018, whose second change we discovered as part of the Close AGN Reference Survey (CARS). Collating over a hundred years worth of photometry from scanned photographic plates and five modern surveys we find a historic outburst between ~1935-1960, with variation in Johnson B magnitude of ~0.8 that is consistent with Mrk 1018's brightness before and after its latest changing look event in the early 2010s. Using the combined modern and historic data, a Generalised Lomb-Scargle suggests broad feature with P = 29-47 years. Its width and stability across tests, as well as the turn-on speed and bright phase duration of the historic event suggests a timescale associated with long-term modulation, such as via rapid flickering in the accretion rate caused by the Chaotic Cold Accretion model…
Peer Reviews
No public reviews on file for this paper yet. If you reviewed it on a platform where reviews are public (OpenReview, ICLR, NeurIPS, ICML), you can paste yours below so the community can read it here.
Videos
No videos yet. Explain this paper in a talk, walkthrough, or lecture? Add one.
