47 citations · 224 across the 22 of their papers we have counts for
14 papers · 1 filter
Revealing the Physical Driver of the Baldwin Effect: Gas Density in the Broad-Line Region
Wen-Qiang Liang, Zhi-Fu Chen, Rui-Jing Lu +8
The Baldwin effect --- the inverse correlation between the equivalent width of emission lines and the continuum luminosity in active galactic nuclei (AGNs) --- has been known for n…
The infrared traced star formation rates of associated absorption lines quasars
Zhe-Geng Chen, Rui-Jing Lu, Zhi-Fu Chen +4
Some optically selected quasars exhibit Mg II assoicated absorption lines (AALs), and its origin remains unclear. In this paper, we compile a sample of 1769 quasars, with or withou…
The Detection Rate of Associated \mgii\ Absorption Lines in Quasars Depends on Their Radio Emission
Chen ZF, Luis C. Ho
In active galactic nuclei, jet-driven feedback plays a significant role in influencing the properties of gas within their host galaxy and the circumgalactic medium. By combining ob…
Narrow [O III] emission lines as a potential proxy for the evolutionary stage of quasars
Zhi-fu Chen, Zhe-Geng Chen, Xing-long Peng +1
Radio spectral shape of quasars can provide insight into the ages of quasars. We have compiled data for 1804 quasars with from the Sloan Digital Sky Survey (SDSS). Add…
The Transition from Galaxy-wide Gas Inflow to Outflow in Quasar Host Galaxies
Zhicheng He, Zhifu Chen, Guilin Liu +8
Galactic-wide outflows driven by active galactic nuclei (AGNs) is a routinely invoked feedback mechanism in galaxy evolution models. Hitherto, the interplay among the interstellar…
The Study of Circumgalactic Medium with Quasar Pairs
Zhi-Fu Chen, Huan-Chang Qin, Jin-Ting Cai +4
We have collected 10025 foreground-background quasar pairs with projected distances kpc from the large quasar catalog of the SDSS DR16Q. We investigate the properties of…
Evidence for the connection between star formation rate and evolutionary phases of quasars
Zhifu Chen, Zhicheng He, Luis C. Ho +5
Both theory and observations suggest that outflows driven by an active central supermassive black hole (SMBH) has a feedback effect on shaping the global properties of the host gal…
The detections of inflowing gas from narrow absorption lines at the parsec scale
Zhi-Fu Chen, Minfeng Gu, Zhicheng He +4
Inflows at the dusty torus and smaller scales is crucial to investigate the process of supermassive black hole accretion. However, only few cases of inflowing gas at small scales h…
The correlated variations of C IV narrow absorption lines and quasar continuum
Zhi-Fu Chen, Ting-Ting Pang, Bing He +1
We assemble 207 variable quasars from the Sloan Digital Sky Survey, all with at least 3 observations, to analyze C IV narrow absorption doublets, and obtain 328 C IV narrow absorpt…
The associated absorption features in quasar spectra of the Sload Digital Sky survey .I. \MgII\ absorption doublets
Chen Zhi-Fu, Huang Wei-Rong, Pang Ting-Ting +5
Using the SDSS spectra of quasars included in the DR7Q or DR12Q catalogs, we search for Mg II narrow absorption doublets in the spectra data around Mg II emission lines. We obtain…
Collective properties of quasar narrow associated absorption lines
Chen Zhi-Fu, Pan Da-Sheng
This paper statistically investigates the properties of C IV and Mg II narrow absorption lines (NALs) to look for velocity cuts that can well constrain quasar-associated NALs. The…
Narrow C IV absorption doublets on quasar spectra of the Baryon Oscillation Spectroscopic Survey
Chen Zhi-fu, Gu Qiu-sheng, Zhou Luwenjia +1
In this paper, we extend our works of Papers I and II, which are assigned to systematically survey \CIVab\ narrow absorption lines (NALs) with \zabs\zem\ on quasar spectra of…
Narrow absorption lines with two observations of Sloan Digital Sky Survey
Zhi-Fu Chen, Qiu-Sheng Gu, Yan-Mei Chen +1
We assemble 3524 quasars from Sloan Digital Sky Survey (SDSS) with repeated observations to search for variations of narrow C IV1548,1551 and Mg II2796,2803 absorption doublets in…
Catalog of narrow C IV absorption lines in BOSS (II): for quasars with zem > 2.4
Zhi-Fu Chen, Yi-Ping Qin, Ming Qin +2
As the second work in a series of papers aiming to detect absorption systems in the quasar spectra of the Baryon Oscillation Spectroscopic Survey, we continue the analysis of Paper…