38 citations · 73 across the 4 of their papers we have counts for
7 papers
Measuring the Virial Factor in SDSS DR5 Quasars with Redshifted H and Fe ii Broad Emission Lines
H. T. Liu, Hai-Cheng Feng, Sha-Sha Li +1
Under the hypothesis of gravitational redshift induced by the central supermassive black hole, and based on line widths and shifts of redward shifted H and Fe ii broad emission…
Velocity-resolved Reverberation Mapping of Changing-look AGN NGC 2617
Hai-Cheng. Feng, H. T. Liu, J. M. Bai +6
NGC 2617 has attracted a lot of attention after the detection of the changes in spectral type, and its geometry and kinematics of broad-line region (BLR) are still ambiguous. In th…
Reverberation Mapping of Changing-look Active Galactic Nucleus NGC 3516
Hai-Cheng. Feng, Chen. Hu, Sha-Sha. Li +7
The changes of broad emission lines should be a crucial issue to understanding the physical properties of changing-look active galactic nucleus (CL-AGN). Here, we present the resul…
Quasi-simultaneous Spectroscopic and Multi-band Photometric Observations of Blazar S5 0716+714 during 2018-2019
Hai-Cheng. Feng, H. T. Liu, J. M. Bai +4
In order to study short timescale optical variability of -ray blazar S5 0716+714, quasi-simultaneous spectroscopic and multi-band photometric observations were performed from 20…
Search for Intra-day Optical Variability in -ray--loud Blazars S5 0716+714 and 3C 273
H. T. Liu, Hai Cheng Feng, Y. X. Xin +3
We present the photometric observations of blazars S5 0716+714 and 3C 273 with high temporal resolution (30--60s) in the or bands. The observations were performed with a 1.…
Search for intra-day optical variability in Mrk 501
Hai-Cheng Feng, H. T. Liu, X. L. Fan +5
We present our observations of the optical intra-day variability (IDV) in -ray BL Lac object Mrk 501. The observations were run with the 1.02 m and 2.4 m optical telescopes at Y…