Seyfert galaxies with Swift: giant flares, rapid drops, and other surprises

TL;DR

Swift observations have revealed extreme variability in Seyfert galaxies, including giant flares and rapid drops, providing new insights into AGN physics and emission mechanisms.

Contribution

This study presents new monitoring results of highly variable Seyfert galaxies with Swift, including the detection of a second outburst of IC 3599 and implications for AGN models.

Findings

Detection of a new outburst of IC 3599.

Observation of giant flares and rapid variability in Seyfert galaxies.

Implications for accretion-disk variability and binary supermassive black holes.

Abstract

Swift has initiated a new era of understanding the extremes of active galactic nuclei (AGN) variability, their drivers and underlying physics. This is based on its rapid response, high sensitivity, good spatial resolution, and its ability to collect simultaneously X--ray-to-optical SEDs. Here, we present results from our recent monitoring campaigns with Swift of highly variable AGN, including outbursts, deep low states, and unusual long-term trends in several Seyfert galaxies including Mrk 335, WPVS007, and RXJ2314.9+2243. We also report detection of a new X-ray and optical outburst of IC 3599 and our Swift follow-ups. IC 3599 was previously known as one of the AGN with the highest-amplitude outbursts. We briefly discuss implications of this second outburst of IC 3599 for emission scenarios including accretion-disk variability, repeat tidal disruption events, and the presence of a binary supermassive black hole.