17 citations · 32 across the 7 of their papers we have counts for
8 papers
First Observational Evidence for QPO-like Coevolution between Characteristic Damping Timescales and X-ray Time Lags among AGNs
Haoyang Zhang, Li Zhang
Quasi-periodic oscillations (QPOs) and stochastic variability provide complementary probes of the inner accretion flow around supermassive black holes in active galactic nuclei (AG…
Detection of a puzzling dual-superorbital hard X-ray modulation in the X-ray binary GX 301-2
Haoyang Zhang, Li Zhang
The superorbital modulations (SMs) observed in wind-fed X-ray binaries remain a puzzling phenomenon in astrophysics. To investigate this behavior observationally, we analyzed the l…
A Mass-Independent Damping Timescale in Black Hole Accretion Systems
Haoyang Zhang, Shenbang Yang, Li Zhang +1
The scaling laws reveal the underlying structural similarities shared by astrophysical systems across vastly different scales. In black hole accretion systems, the scaling relation…
Detection of Quasi-periodic Oscillations in the -Ray Light Curve of 4FGL J0309.9-6058
Jingyu Wu, Zhihao Ouyang, Hubing Xiao +7
In this work, we report, for the first time, a quasi-periodic oscillation (QPO) in the -ray band of 4FGL J0309.9-6058, also known as PKS 0308-611. We employed three analytical m…
Revisiting the observation-theory confrontation in high-frequency QPOs:a new QPO in NGC 5506, intermediate mass black holes, and the crucial role of accretion state
Haoyang Zhang, Lingwei Meng, Li Zhang +1
The scale invariance of accretion processes (SIAP) is crucial for understanding the physical processes of black hole accretion systems at different scales. When applying this rule…
Discovering the Mass-Scaled Damping Timescale from Microquasars to Blazars
Haoyang Zhang, Shenbang Yang, Benzhong Dai
Studying the variability of the accretion disks of black holes and jets is important to identify their internal physical processes. In this letter, we obtain the characteristic dam…
The detection of possible -ray quasi-periodic modulation with 600 days from the blazar S2 0109+22
Haoyang Zhang, Fan Wu, Benzhong Dai
In this work, we analyzed the long term gamma-ray data by a Fermi Large Area Telescope (Fermi-LAT) of blazar S2 0109+22, ranging from 2008 to 2023. The quasi-periodic oscillations…
Search for X-ray Quasi-periodicity of six AGNs using Gaussian Process method
Haoyang Zhang, Shenbang Yang, Benzhong Dai
The quasi-periodic oscillations (QPOs) found in active galactic nuclei (AGNs) are a very interesting observational phenomenon implying an unknown physical mechanism around supermas…