The blueshift of the [O III] emission line in NLS1s

We investigate the radial velocity difference between the narrow emission-line components of [O III] $\lambda$ 5007 and H$\beta$ in a sample of 150 SDSS NLS1s. Seven "blue outliers" with [O III] blueshifted by more than 250 \kms are found. A strong correlation between the [O III] blueshift and the Eddington ratio is found for these seven "blue outliers". For the entire sample, we found a modest correlation between the blueshift and the linewidth of the narrow component of the [O III] line. The reflected profile of [O III] indicates two kinematically and physically distinct regions. The [O III] linewidth depends not only on the bulge stellar gravitational potential, but also on the central black hole potential.