Mechanism of the Changing Look phenomenon in Active Galactic Nuclei

Abstract

Changing-look phenomenon observed now in a growing number of active galaxies challenges our understanding of the accretion process close to a black hole. We propose a simple explanation for periodic outbursts in sources operating at a few per cent of the Eddington limit. The mechanism is based on two relatively well understood phenomena: radiation pressure instability and formation of the inner optically thin Advection-Dominated Accretion Flow. The limit cycle behaviour takes place in a relatively narrow transition zone between the standard disk and optically thin flow. Large changes in the cold disk are due to the irradiation by the hot flow with accretion rate strongly varying during the cycle. The model gives quantitative predictions and works well for multiple outbursts of NGC 1566.

This version was rejected from ApJ, we extended it significantly and published this new version in A&A (arxiv:2007.06441)

Cited by in corpus (10)

• Understanding extreme quasar optical variability with CRTS: II. Changing-state quasars
• Improving Damped Random Walk parameters for SDSS Stripe 82 Quasars with Pan-STARRS1
• The Sloan Digital Sky Survey Reverberation Mapping Project: Accretion and Broad Emission Line Physics from a Hypervariable Quasar
• Evolution of a Relativistic Outflow and X-ray Corona in the Extreme Changing-Look AGN 1ES 1927+654
• A Systematic Analysis of Stellar Populations in the Host Galaxies of Changing-look AGNs
• The post-maximum behaviour of the changing-look Seyfert galaxy NGC 1566
• Variable mass accretion and failed wind explain changing look phenomena in NGC 1365
• Tracing the AGN/X-ray Binary Analogy with Light Curves of Individual Changing-Look AGN
• Changing looks of the nucleus of the Seyfert galaxy NGC 1566 compared with other changing-look AGNs
• Evidence for changing-look AGNs is caused by change of accretion mode