11 papers
SDSS J153231.80+420342.7: a triple black hole candidate with a close binary black hole
Qi Zheng, YiWen Jiang, Xue-Guang Zhang +1
We report a triple black hole candidate with a close binary black hole (BBH) in the blue quasar SDSS J153231.80+420342.7 (=SDSS J1532) at a redshift of 0.209. It shows double-peake…
Spectroscopic study of the broad component of [O III]λ5007 profile in type 1 AGNs
Qi Zheng, Yansong Ma, Xueguang Zhang +1
The spectra of type 1 active galactic nuclei (AGNs) often exhibit broad component in [O III]5007, which are typically blue-shifted and associated with strong outflows. We syste…
Changing-look Active Galactic Nuclei from the Dark Energy Spectroscopic Instrument. V. Dramatic Variability in High-Ionization Broad Emission Lines
Zhi-Qiang Chen, Jun-Jie Jin, Wei-Jian Guo +10
We present a systematic search for changing-look (CL) quasars at high redshift z > 0.9 by cross-matching the spectroscopic datasets from the Dark Energy Spectroscopic Instrument Da…
Dual core system candidates: a sample of objects with large velocity offset between absorption and narrow emission lines
Zheng Qi, Zhang Xueguang, Yuan Qirong
We present a sample of 28 objects at z<0.3 from Data Release 16 of the Sloan Digital Sky Survey (SDSS DR16) with large velocity offset (> 200 km/s) of narrow H and H emissi…
AGN-Driven Biconical Outflows as the Origin of the Double-Peaked [O~{\sc iii}] doublet in SDSS J134733.36+121724.27
PeiZhen Cheng, XingQian Chen, GuiLin Liao +4
In this manuscript, we recheck the spectroscopic properties of SDSS J134733.36+121724.27 (4C+12.50), confirming the presence of the double-peaked [O~{\sc iii}]Ã…
On type 1 active galactic nuclei with double-peaked [O~{\sc iii}]. II. properties of long-term optical variability
Qi Zheng, Xingyv Zhu, Xueguang Zhang +1
Double-peaked \oiii~profiles could potentially indicate kiloparsec-scale dual AGNs. We analyze long-term optical light curves of 35 type 1 AGNs with such features from our recent c…