A Census of Ionized Gas Outflows in Type 1 AGNs: Gas Outflows in AGNs. V.

Abstract

We present a systematic study of ionized gas outflows based on the velocity shift and dispersion of the [O iii ] λ 5007 emission line using a sample of ∼5000 Type 1 AGNs at z  < 0.3 selected from the Sloan Digital Sky Survey. This analysis is supplemented by the gas kinematics of Type 2 AGNs from Woo et al. For the majority of Type 1 AGNs (i.e., ∼89%), the [O iii ] line profile is best represented by a double Gaussian model, presenting the kinematic signature of the nonvirial motion. Blueshifted [O iii ] is more frequently detected than redshifted [O iii ] by a factor of 3.6 in Type 1 AGNs, while the ratio between blueshifted and redshifted [O iii ] is only 1.08 in Type 2 AGNs due to the projection and orientation effect. The fraction of AGNs with outflow signatures is found to increase steeply with [O iii ] luminosity and Eddington ratio, while Type 1 AGNs have larger velocity dispersion and more negative velocity shift than Type 2 AGNs. The [O iii ] velocity–velocity dispersion diagram of Type 1 AGNs expands toward higher values with increasing luminosity and Eddington ratio, suggesting that the radiation pressure or wind is the main driver of gas outflows, as similarly found in Type 2 AGNs. In contrast, the kinematics of gas outflows is not directly linked to the radio activity of AGNs.