205 citations · 918 across the 25 of their papers we have counts for
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The Most Luminous H Reverberation Mapping of E1821+643 Indicates the Lower Boundary of the Radius-Luminosity Relation
Sha-Sha Li, Hai-Cheng Feng, Jiancheng Wu +5
The radius-luminosity (-) relation is fundamental to active galactic nucleus (AGN) studies, enabling supermassive black hole (SMBH) mass estimates and AGN-ba…
Morpho-Photometric Classification of KiDS DR5 Sources Based on Neural Networks: A Comprehensive Star-Quasar-Galaxy Catalog
Hai-Cheng Feng, Rui Li, Nicola R. Napolitano +14
We present a novel multimodal neural network (MNN) for classifying astronomical sources in multiband ground-based observations, from optical to near infrared, to separate sources i…
Measuring the Virial Factor in SDSS DR7 AGNs with Redshifted H and H Broad Emission Lines
H. T. Liu, Hai-Cheng Feng, Sha-Sha Li +2
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 H broad emission l…
Velocity-resolved Reverberation Mapping of Changing-look Active Galactic Nucleus NGC~4151 During Outburst Stage: Evidence for Kinematics Evolution of Broad-line Region
Sha-Sha Li, Hai-Cheng Feng, H. T. Liu +6
Changing-look active galactic nucleus NGC~4151, which has attracted a lot of attention, is undergoing the second dramatic outburst stage in its evolutionary history. To investigate…
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…
A new method to measure the virial factors in the reverberation mapping of AGNs
H. T. Liu, H. C. Feng, J. M. Bai
Based on the gravitational redshift, one prediction of Einstein's general relativity theory, of broad optical emission lines in active galactic nuclei (AGNs), a new method is propo…
Influences of Radiation Pressures on Mass Estimates of Supermassive Black Holes in AGNs
H. T. Liu, H. C. Feng, J. M. Bai
In this paper, we investigate the influences of two continuum radiation pressures of the central engines on the black hole mass estimates for 40 active galactic nuclei (AGNs) with…
Constraints on black hole massess with timescales of variations in blazars
H. T. Liu, J. M. Bai
In this paper, we investigated the issue of black hole masses and minimum timescales of jet emission for blazars. We proposed a sophisticated model that sets an upper limit to the…
Revisiting Correlations Between Broad-Line and Jet Emission Variations for AGNs: 3C 120 and 3C 273
H. T. Liu, J. M. Bai, H. C. Feng +1
We restudy the issue of cross-correlations between broad-line and jet emission variations, and aim to locate the position of radio (and gamma-ray) emitting region in jet of active…