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

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.

### Cited Authors

• Katebi, R; Chornock, R; Berger, E; Jones, DO; Lunnan, R; Margutti, R; Rest, A; Scolnic, DM; Burgett, WS; Kaiser, N; Kudritzki, R-P; Magnier, EA; Wainscoat, RJ; Waters, C

### Published Date

• June 15, 2019

### Published In

• Monthly Notices of the Royal Astronomical Society

• 48 /