7 papers
Detection of Variability in Seyfert 2 Galaxies and Measurement of the Optical Scattering Region Size
Natalie Kovacevic, Xinyu Dai, Heechan Yuk +5
One main theme of the Unification Model of active galactic nuclei is that there is an obscuring torus structure blocking the direct view of the central engine for Seyfert 2 galaxie…
The shortest detected intra-day variability of active galactic nuclei in TESS survey
Heechan Yuk, Xinyu Dai, Natalie Kovacevic
AGNs are known to be variable in almost all wavelengths and timescales. The shortest variability timescale of AGNs can be used to probe the smallest scale structures within AGNs. W…
A Decade-Long Increasing Mid-Infrared Luminosity in Galaxy NGC6447: a Turning-On Candidate of Active Galactic Nucleus
Xinyu Dai, Nate Adams, Natalie Kovacevic +6
It is widely expected that the obscured accretion stage can be the initial turning-on stage of active galactic nuclei from quiescent galaxies. We present mid-infrared light curves…
Environmental Dependence of X-Ray Emission From The Least Massive Galaxies
Marko MiÄiÄ, Xinyu Dai, Nick Shumate +2
The low-mass end of low-mass galaxies is largely unexplored in AGN studies, but it is essential for extending our understanding of the black hole-galaxy coevolution. We surveyed th…
Comparing Optical Variability of Type 1 and Type 2 AGN from the BAT 9-Month Sample using ASAS-SN and TESS Surveys
Natalie Kovacevic, Xinyu Dai, Heechan Yuk +6
We present an optical variability analysis and comparison of the samples of Seyfert 1 and 2 galaxies, selected from the \textit{Swift} 9-month BAT catalog, using the light curves f…
Multi-wavelength and Environmental Properties of Variability Selected Low Luminosity Active Galactic Nuclei
Heechan Yuk, Xinyu Dai, Marko MiÄiÄ
We present the multi-wavelength and environmental properties of 37 variability-selected active galactic nuclei (AGNs), including 30 low luminosity AGNs (LLAGNs), using a high caden…