Dynamical Mass of Type 2 Seyfert Nuclei

We have derived the masses of central objects (MBH) of nine type 2 Seyfert nuclei using the observational properties of the hidden broad Hβ emission. We obtain the average dynamical mass log (MBH/M☉) ≃ 8.00 ± 0.51 - 0.475 log (τes/1), where τes is the optical depth for electron scattering. If τes ~ 1, this average mass is almost comparable with those of type 1 Seyfert nuclei. However, if τes ≪ 1, as is usually considered, the average mass of type 2 Seyfert nuclei may be more massive than that of type 1 Seyfert nuclei. We discuss implications for issues concerning both the current unified model of Seyfert nuclei and physical conditions of the electron scattering regions.