The destruction and recreation of the X-ray corona in a changing-look Active Galactic Nucleus

Abstract

We present the drastic transformation of the X-ray properties of the active galactic nucleus 1ES 1927+654, following a changing-look event. After the optical/UV outburst the power-law component, produced in the X-ray corona, disappeared, and the spectrum of 1ES 1927+65 instead became dominated by a blackbody component ($kT\sim 80-120$ eV). This implies that the X-ray corona, ubiquitously found in AGN, was destroyed in the event. Our dense $\sim 450$ day long X-ray monitoring shows that the source is extremely variable in the X-ray band. On long time scales the source varies up to $\sim 4$ dex in $\sim 100$ days, while on short timescales up to $\sim 2$ dex in $\sim 8$ hours. The luminosity of the source is found to first show a strong dip down to $\sim 10^{40}\mathrm{erg}{\mathrm{s}}^{-1}$, and then a constant increase in luminosity to levels exceeding the pre-outburst level $\gtrsim$300 days after the optical event detection, rising up asymptotically to $\sim 2\times 10^{44}\mathrm{erg}{\mathrm{s}}^{-1}$. As the X-ray luminosity of the source increases, the X-ray corona is recreated, and a very steep power-law component ($\Gamma \simeq 3$) reappears, and dominates the emission for 0.3-2 keV luminosities $\gtrsim 10^{43.7}\mathrm{erg}{\mathrm{s}}^{-1}$, $\sim 300$ days after the beginning of the event. We discuss possible origins of this event, and speculate that our observations could be explained by the interaction between the accretion flow and debris from a tidally disrupted star. Our results show that changing-look events can be associated with dramatic and rapid transformations of the innermost regions of accreting SMBHs.

ApJL in press

References in corpus (8)

• X-ray Properties of Black-Hole Binaries
• BAT AGN Spectroscopic Survey - V. X-ray properties of the Swift/BAT 70-month AGN catalog
• The Discovery of the First "Changing Look" Quasar: New Insights into the Physics & Phenomenology of AGN
• X-ray quasi-periodic eruptions from the galactic nucleus of RX J1301.9+2747
• GSN 069 -- A Tidal Disruption Near-Miss
• Repetitive Patterns in Rapid Optical Variations in the Nearby Black-hole Binary V404 Cygni
• Enhanced activity of massive black holes by stellar capture assisted by a self-gravitating accretion disc
• A Tidal Disruption Event Candidate Discovered in the Active Galactic Nucleus SDSS J022700.77-042020.6

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