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On the Time Scales of Optical Variability of AGN and the Shape of Their Optical Emission Line Profiles

Astronomical Observatory, Volgina 7, 11060 Belgrade, Serbia
National Institute for Astrophysics (INAF), Astronomical Observatory of Padova, IT 35122 Padova, Italy
Author to whom correspondence should be addressed.
Atoms 2019, 7(1), 26;
Received: 8 December 2018 / Revised: 5 February 2019 / Accepted: 6 February 2019 / Published: 14 February 2019
(This article belongs to the Special Issue SPIG2018)
PDF [635 KB, uploaded 22 February 2019]
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The mechanism of the optical variability of active galactic nuclei (AGN) is still very puzzling. It is now widely accepted that the optical variability of AGN is stochastic, producing red noise-like light curves. In case they were to be periodic or quasi-periodic, one should expect that the time scales of optical AGN variability should relate to orbiting time scales of regions inside the accretion disks with temperatures mainly emitting the light in this wavelength range. Knowing the reverberation scales and masses of AGN, expected orbiting time scales are in the order of decades. Unfortunately, most of monitored AGN light curves are not long enough to investigate such time scales of periodicity. Here we investigate the AGN optical variability time scales and their possible connections with the broad emission line shapes. View Full-Text
Keywords: AGN; black holes; gravitational waves; binary black holes; quasars AGN; black holes; gravitational waves; binary black holes; quasars

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Bon, E.; Marziani, P.; Jovanović, P.; Bon, N. On the Time Scales of Optical Variability of AGN and the Shape of Their Optical Emission Line Profiles. Atoms 2019, 7, 26.

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