9 papers
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,…
Gaussian process analysis of type-B quasiperiodic oscillations in the black hole X-ray binary MAXI J1348-630
Yiran Wang, Ruican Ma, Haiyun Zhang +1
We analyzed Insight-HXMT data of the black hole X-ray binary MAXI J1348-630 during the type-B QPO phase of its 2019 outburst. Using the Gaussian process method, we applied an addit…
Gaussian Process Modeling Coronal X-ray Variability of Active Galactic Nuclei
Haiyun Zhang, Dahai Yan, Li Zhang +1
The corona is an integral component of active galactic nuclei (AGNs) which can produce the X-ray emission. However, many of its physical properties and the mechanisms powering this…
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…
Patterns of X-ray and -ray Flares: from Blazar to Maganetar and Sun
Haiyun Zhang, Dahai Yan, Lijuan Dong +6
Using Gaussian process methods, we analyzed the light curves of three extreme solar X-ray flares observed by the RHESSI satellite. Their variability characteristics were then compa…
Pattern and Origin for the Extreme -ray Flares of 3C 454.3 and 3C 279: An Astrophysical Critical Damper?
Haiyun Zhang, Dahai Yan, Jianeng Zhou +2
We apply a Gaussian process method to the extreme -ray flares of 3C 454.3 and 3C 279 to discover the variable patterns and then to investigate the physical origins of the giant…