205 citations · 918 across the 25 of their papers we have counts for
25 papers
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…
Unprecedented Continuum Time Delay Variation Phenomenon in an Active Supermassive Black Hole
Shuying Zhou, Mouyuan Sun, Hai-Cheng Feng +12
Resolving the accretion disks and broad line regions (BLRs) of active galactic nuclei (AGNs) can probe the physics behind supermassive black holes (SMBHs) fueling and weigh SMBHs.…
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…
Calculations with spectroscopic accuracy: energies and transition rates in the nitrogen isoelectronic sequence from Ar XII to Zn XXIV
K. Wang, R. Si, W. Dang +11
Combined relativistic configuration interaction and many-body perturbation calculations are performed for the 359 fine-structure levels of the , , , $2s^2…
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…
Hints of correlation between broad-line and radio variations for 3C 120
H. T. Liu, J. M. Bai, J. M. Wang +1
In the paper, we investigate correlation between broad-line and radio variations for broad-line radio galaxy 3C 120. By the z-transformed discrete correlation function method and t…
Constraining broad-line regions from time lags of broad emission lines relative to radio emission
H. T. Liu, J. M. Bai, J. M. Wang +1
In this paper, a new method is proposed to estimate the broad-line region sizes of UV lines . It is applied to 3C 273. First, we derive the time lags of rad…
Isotopic Composition of Light Nuclei in Cosmic Rays: Results from AMS-01
01 Collaboration
The variety of isotopes in cosmic rays allows us to study different aspects of the processes that cosmic rays undergo between the time they are produced and the time of their arriv…
Locating positions of γ-ray--emitting regions in blazars
H. T. Liu, J. M. Bai, J. M. Wang
We propose a new method to locate the gamma-ray--emitting positions R_g from the measured time lags T_ob of gamma-ray emission relative to broad emission lines. The method is also…
Absorption of 10 Gev--1 Tev Gamma Rays from 3C 279
J. M. Bai, H. T. Liu, L. Ma
In this paper, we revisit gamma-ray--emitting region for 10 GeV--1 TeV gamma rays from 3C 279 through studying the photon-photon absorption optical depth due to the diffuse radiati…
Absorption of 10--200 Gev Gamma Rays by Radiation from BLR in Blazars
H. T. Liu, J. M. Bai
In this paper, we study the photon-photon pair production optical depth for gamma-rays with energies from 10 to 200 GeV emitted by powerful blazars due to the diffuse radiation fie…
Tests for Standard Accretion Disk Models by Variability in Active Galactic Nuclei
H. T. Liu, J. M. Bai, X. H. Zhao +1
In this paper, standard accretion disk models of AGNs are tested using light curves of 26 objects well observed for reverberation mapping. Time scales of variations are estimated b…
Protons in near earth orbit
AMS Collaboration
The proton spectrum in the kinetic energy range 0.1 to 200 GeV was measured by the Alpha Magnetic Spectrometer (AMS) during space shuttle flight STS-91 at an altitude of 380 km. Ab…