4 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…
The Faintest, Extremely Variable X-ray Tidal Disruption Event from a Supermassive Black Hole Binary?
Mengqiu Huang, Yongquan Xue, Shuo Li +30
Tidal disruption events (TDEs), which occur when stars enter the tidal radii of supermassive black holes (SMBHs) and are subsequently torn apart by their tidal forces, represent in…
A Giant Peanut-shaped Ultra-High-Energy Gamma-Ray Emitter Off the Galactic Plane
Zhen Cao, Felix Aharonian, Yunxiang Bai +312
Ultra-high-energy (UHE), exceeding 100 TeV (10^12 electronvolts), γ-rays manifests extreme particle acceleration in astrophysical sources. Recent observations by γ-ray telescopes…
Einstein Probe discovery of EP240408a: a peculiar X-ray transient with an intermediate timescale
Wenda Zhang, Weimin Yuan, Zhixing Ling +136
We report the discovery of a peculiar X-ray transient, EP240408a, by Einstein Probe (EP) and follow-up studies made with EP, Swift, NICER, GROND, ATCA and other ground-based multi-…