AstroSat View of Spectral Transition in the Changing-look Active Galaxy NGC 1566 during the Declining Phase of the 2018 Outburst

  title={AstroSat View of Spectral Transition in the Changing-look Active Galaxy NGC 1566 during the Declining Phase of the 2018 Outburst},
  author={Prakash Tripathi and Gulab Chand Dewangan},
  journal={The Astrophysical Journal},
NGC 1566 is a changing-look active galaxy that exhibited an outburst during 2017–2018 with a peak in 2018 June. We triggered AstroSat observations of NGC 1566 twice in 2018 August and October during its declining phase. Using the AstroSat observations, along with two XMM-Newton observations in 2015 (pre-outburst) and 2018 June (peak outburst), we found that the X-ray power law, the soft X-ray excess, and the disk components showed extreme variability during the outburst. Especially, the soft… 

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Explaining changing-look AGN with state transition triggered by rapid mass accretion rate drop

  • H. NodaC. Done
  • Physics
    Monthly Notices of the Royal Astronomical Society
  • 2018
We model the broadband (optical/UV and X-ray) continuum spectrum of the “changing-look” active galactic nucleus (AGN) Mrk 1018 as it fades from Seyfert 1 to 1.9 in ∼8 years. The brightest spectrum,