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ACTIVE GALACTIC NUCLEI VARIABILITY - Astrophysics Data System

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Last Updated: 03 April 2022

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The Close AGN Reference Survey (CARS). IFU survey data and the BH mass dependence of long-term AGN variability

AGN's objective is to obtain the necessary spatially resolved multiwavelength measurements for unveiled sample of local unobscured luminous AGN. Methods: We report the complete CARS survey design and the associated wide-field optical integral-field unit spectroscopy for all 41 CARS targets, z 0. 1 randomly selected from the Hamburg/ESO survey of luminous unobscured AGN. Max - M 0. 5 relationship; note that we found the greatest correlation between the maximum predicted ENLR size and the black hole mass, consistent with an R ENLR based connection. Using forward modeling, we show the maximum ENLR size as a timescale marker of a single black hole radiative-efficient accretion episode for which we inferred AGN / [M]= 0. 78 +0. 54 for a single black hole radiative-efficient accretion episode for which we delayed AGN [M] 0. 8logM [M ] = 0. 45 0. 48 = 0. 78 +0. 54 versus 0. 47 +0. 54 acce /[M ] [M a acc] a single black hole radiative-efficient accacc] [M acc] accoutput a [M ] a [M ] [M —[M ] /[M ] –1. Our extrapolation of our inferred relationship to higher BH masses is consistent with an independent lifetime estimate from He II proximity zones around luminous AGN at z 3. Conclusions: Although our suggested link between the BH mass and AGN lifetime may be a secondary correlation or affected by unknown biases, it has no practical implications if confirmed. For example, the famous AGN Eigenvector 1 parameter space can be partially explained by the AGN lifetimes. Also, the lack of observational evidence for negative AGN feedback on star formation can be accounted for by such timescale effects.

Source link: https://ui.adsabs.harvard.edu/abs/2022A&A...659A.124H/abstract


Properties of a Previously Unidentified Instrumental Signature in Kepler/K2 That was Confused for AGN Variability

The Kepler satellite may have the most precise photometry of active galactic nuclei available to investigate short-timescale optical variability. We were after quasars from the Sloan Digital Sky Survey who fall within the scopes of view of the Kepler/K2 campaigns. Low-frequency trends that are both non-astrophysical and linked from object to object are dominating Weakly illuminated pixels. After time reversal of one of the campaigns, different targets observed in Campaign 8 and Campaign 16 have almost identical light curves, providing an important clue to understanding this instrumental framework. Temperature fluctuations in K2 are greater in K2 than in the nominal Kepler mission, and we recommend our assertion of temperature-driven focus changes. Further characterization of this signature is essential in the rehabilitating K2 results for use in AGN light curve studies.

Source link: https://ui.adsabs.harvard.edu/abs/2021AJ....162..232M/abstract


Examining AGN UV/optical Variability Beyond the Simple Damped Random Walk

AGN's configuration as a DHO provides more insight into how accretion disks work closer to the supermassive black holes at the heart of AGN. The recently found short-term variation and its relationship with bolometric luminosity also paved the way for new algorithms that would derive basic characteristics of AGN using solely photographic results.

Source link: https://ui.adsabs.harvard.edu/abs/2022arXiv220108943Y/abstract

* Please keep in mind that all text is summarized by machine, we do not bear any responsibility, and you should always check original source before taking any actions

* Please keep in mind that all text is summarized by machine, we do not bear any responsibility, and you should always check original source before taking any actions