The Prevalence of Gas Outflows in Type 2 AGNs. II. 3D Biconical Outflow
  Models
  We present 3D models of biconical outflows combined with a thin dust plane
for investigating the physical properties of the ionized gas outflows and their
effect on the observed gas kinematics in type 2 active galactic nuclei (AGNs).
Using a set of input parameters, we construct a number of models in 3D and
calculate the spatially integrated velocity and velocity dispersion for each
model. We find that three primary parameters, i.e., intrinsic velocity, bicone
inclination, and the amount of dust extinction, mainly determine the simulated
velocity and velocity dispersion. Velocity dispersion increases as the
intrinsic velocity or the bicone inclination increases, while velocity (i.e.,
velocity shifts with respect to systemic velocity) increases as the amount of
dust extinction increases. Simulated emission-line profiles well reproduce the
observed [O III] line profiles, e.g., a narrow core and a broad wing
components. By comparing model grids and Monte Carlo simulations with the
observed [O III] velocity-velocity dispersion (VVD) distribution of ~39,000
type 2 AGNs, we constrain the intrinsic velocity of gas outflows ranging from
~500 km/s to ~1000 km/s for the majority of AGNs, and up to ~1500-2000 km/s for
extreme cases. The Monte Carlo simulations show that the number ratio of AGNs
with negative [O III] velocity to AGNs with positive [O III] velocity
correlates with the outflow opening angle, suggesting that outflows with higher
intrinsic velocity tend to have wider opening angles. These results demonstrate
the potential of our 3D models for studying the physical properties of gas
outflows, applicable to various observations, including spatially integrated
and resolved gas kinematics.
