4 papers
PACHA: Probing AGN Coronae with High-redshift AGN
Xiurui Zhao, Elias Kammoun, Marco Ajello +19
The X-ray emission of active galactic nuclei (AGN) is generally attributed to inverse Compton scattering of accretion-disk photons by hot electrons in a compact corona. In local AG…
Systematic Analysis of Changing-look AGN Variability Using ZTF Light Curves
Huimei Wang, Xue-Bing Wu, Nanyu Yao +5
Changing-look active galactic nuclei (CLAGNs) are a unique population of AGNs that exhibit the appearance (turn-on) or disappearance (turn-off) of broad emission lines. This study…
Sleeping Giants Arise: Monitoring the Return of Three Changing-Look Quasars to Their High States
Laura Duffy, Michael Eracleous, John J. Ruan +2
Changing-look quasars challenge many models of the quasar central engine. Their extreme variability in both the continuum and broad emission-line fluxes on timescales on the order…
Dormancy and Reawakening Over Years: Eight New Recurrent Changing-Look AGNs
Shu Wang, Jong-Hak Woo, Elena Gallo +5
We report the discovery of eight new recurrent changing-look (CL) active galactic nuclei (AGNs), including seven re-brightening turn-off AGNs and one fading turn-on AGN. These syst…