9 papers
Revisiting the X-ray Variability Plane of AGNs: The Significant Role of the Photon Index
Ruisong Xia, Hao Liu, Yongquan Xue +9
X-ray variability provides a powerful probe of the innermost regions of active galactic nuclei (AGNs), offering valuable insights into the accretion process and the structure of th…
Possible quasi-periodic optical oscillations of ZTF blazars
Na Wang, Guowei Ren, Shun Zhang +3
Based on the Zwicky Transient Facility (ZTF), we selected 10 blazars as our sample sources. Among these, we found four blazars (J 0923.5+4125, J 1221.3+3010, J 1503.5+4759, and J 1…
Baseline-Aware Dependence fitting for DAmping Timescales (BADDAT): A Nearly Unbiased Approach to Constraining Optical Variability Dependence on Physical Properties of Active Galactic Nuclei
Ruisong Xia, Zhen-Yi Cai, Yongquan Xue +7
Active galactic nuclei (AGNs) exhibit stochastic optical variability, commonly characterized by a damped random walk. The damping timescale is of particular interest because it is…
A characteristic optical variability time scale in jetted active galactic nuclei: a large gamma-ray emission sample
Dingrong Xiong, Mouyuan Sun, Jun-Xian Wang +14
The variability mechanisms from jetted AGNs are still under debate. Here the damped random walk (DRW) model, implemented through Gaussian Processe (GPs), is used to fit the l…
The origin of X-ray intra-day variability in HBL PKS 2155-304
W. Hu, J. L. Kang, J. X. Wang +2
The origin and physics of X-ray intra-day variability (IDV) in blazars, which is a long-standing issue, is studied by modelling the broad-band X-ray spectrum, the light curves (LCs…
SMBH binary candidate PKS J2134-0153: Possible multi-band periodic variability and inter-band time lags
Guowei Ren, Mouyuan Sun, Nan Ding +2
Studying the periodic flux-variation behavior of blazars is vital for probing supermassive black hole binaries and the kinematics of relativistic jets. In this work, we report the…
How Long Will the Quasar UV/Optical Flickering Be Damped? II. the Observational Test
Guowei Ren, Shuying Zhou, Mouyuan Sun +1
The characteristic timescale at which the variability of active galactic nuclei (AGNs) turns from red noise to white noise can probe the accretion physics around supermassive black…
Sizes of active galactic nuclei inhomogeneous disks -- large in microlensing, small in reverberation mapping
Guowei Ren, Mouyuan Sun, Jun-Xian Wang +1
Magnetohydrodynamics (MHD) turbulence can drive significant temperature fluctuations in the accretion disk of an active galactic nucleus (AGN). As a result, the disk can be highly…
How long will the quasar UV/optical flickering be damped?
Shuying Zhou, Mouyuan Sun, Zhen-Yi Cai +3
The UV/optical light curves of Active Galactic Nuclei (AGNs) are commonly described by the Damped Random Walk (DRW) model. However, the physical interpretation of the damping times…