PS1-13cbe: The Rapid "Turn on" of a Seyfert 1

Reza Katebi; Ryan Chornock; Edo Berger; David O. Jones; Ragnhild Lunnan; Raffaella Margutti; Armin Rest; Daniel M. Scolnic; William S. Burgett; Nick Kaiser; Rolf-Peter Kudritzki; Eugene A. Magnier; Richard J. Wainscoat; Christopher Waters

arXiv · 1811.03694

PS1-13cbe: The Rapid "Turn on" of a Seyfert 1

Reza Katebi·Ryan Chornock·Edo Berger·David O. Jones·Ragnhild Lunnan·Raffaella Margutti·Armin Rest·Daniel M. Scolnic·William S. Burgett·Nick Kaiser·Rolf-Peter Kudritzki·Eugene A. Magnier·Richard J. Wainscoat·Christopher Waters

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Abstract

We present a nuclear transient event, PS1-13cbe, that was first discovered in the Pan-STARRS1 survey in 2013. The outburst occurred in the nucleus of the galaxy SDSS J222153.87+003054.2 at $z = 0.12355$, which was classified as a Seyfert 2 in a pre-outburst archival Sloan Digital Sky Survey (SDSS) spectrum. PS1-13cbe showed the appearance of strong broad H$\alpha$ and H$\beta$ emission lines and a non-stellar continuum in a Magellan spectrum taken 57 days after the peak of the outburst that resembled the characteristics of a Seyfert 1. These broad lines were not present in the SDSS spectrum taken a decade earlier and faded away within two years, as observed in several late-time MDM spectra. We argue that the dramatic appearance and disappearance of the broad lines and factor of $\sim 8$ increase in the optical continuum is most likely caused by variability in the pre-existing accretion disk than a tidal disruption event, supernova, or variable obscuration. The timescale for the turn-on of the optical emission of $\sim 70$ days observed in this transient is among the shortest observed in a "changing look" active galactic nucleus.

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Reza Katebi, Ryan Chornock, Edo Berger, David O. Jones, Ragnhild Lunnan, Raffaella Margutti, Armin Rest, Daniel M. Scolnic, William S. Burgett, Nick Kaiser, Rolf-Peter Kudritzki, Eugene A. Magnier, Richard J. Wainscoat, Christopher Waters. 2018-11-08. PS1-13cbe: The Rapid "Turn on" of a Seyfert 1. https://arxiv.org/abs/1811.03694

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