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We perform a systematic study of outflow in the narrow-line region (NLR) of active galactic nuclei (AGNs) at $zsim0.4-0.8$ basing upon a large sample of $sim900$ quasars at $zsim 0.4-0.8$. The sample is extracted from the Sloan Digital Sky Survey by mainly requiring 1) the g-band magnitude is brighter than 19 magnitude; and 2) the [OIII]$lambda5007$ emission line has a signal-to-noise ration larger than 30. Profiles of multiple emission lines are modeled by a sum of several Gaussian functions. The spectral analysis allows us to identify 1) a prevalence of both [OIII]$lambda5007$ line blue asymmetry and bulk velocity blueshift of both [NeIII]$lambda3869$ and [NeV]$lambda3426$ lines, when the [ion{O}{2}]$lambda3727$ line is used as a reference. The velocity offset of [ion{O}{3}]$lambda5007$ line is, however, distributed around zero value, except for a few outliers. 2) not only the significant [OIII]$lambda5007$ line asymmetry, but also the large bulk velocity offsets of [NeIII]$lambda3869$ and [NeV]$lambda3426$ emission lines tend to occur in the objects with high $L/L_{mathrm{Edd}}$, which is considerably consistent with the conclusions based on local AGNs. With three $M_{mathrm{BH}}$ estimation methods, the significance level of the trend is found to be better than $2.9sigma$, $3.2sigma$ and $1.8sigma$ for [OIII], [NeIII] and [NeV], respectively. rm After excluding the role of radio jets, the revealed dependence of NLR gas outflow on $L/L_{mathrm{Edd}}$ allows us to argue that the pressure caused by the wind/radiation launched/emitted from central supermassive black hole is the most likely origin of the outflow in these distant quasars, which implies that the outflow in luminous AGNs up to $zsim1$ have the same origin.
High-redshift quasars typically have their redshift determined from rest-frame ultraviolet (UV) emission lines. However, these lines, and more specifically the prominent C IV $lambda 1549$ emission line, are typically blueshifted yielding highly unce
We present the correlations between stellar mass, star formation rate (SFR) and [NII]/Ha flux ratio as indicator of gas-phase metallicity for a sample of 222 galaxies at 0.8 < z < 2.6 and log(M*/Msun)=9.0-11.5 from the LUCI, SINS/zC-SINF and KMOS3D s
We investigate the relation between star formation rates ($dot{M}_{s}$) and AGN properties in optically selected type 1 quasars at $2<z<3$ using data from Herschel and the SDSS. We find that $dot{rm{M}}_s$ remains approximately constant with redshift
The most luminous quasars at high redshift harbour the fastest-growing and most massive black holes in the early Universe. They are exceedingly rare and hard to find. Here, we present our search for the most luminous quasars in the redshift range fro
Significant clustering around the rarest luminous quasars is a feature predicted by dark matter theory combined with number density matching arguments. However, this expectation is not reflected by observations of quasars residing in a diverse range