Dynamical Mass of Type 2 Seyfert Nuclei

We have derived the masses of central objects ($M_{BH}$) of nine type 2Seyfert nuclei using the observational properties of the hidden broad H$\beta$emission. We obtain the average dynamical mass, log$(M_{BH} / M_\odot) \simeq8.00 \pm 0.51 - 0.475 log (\tau_{es}/1)$ where $\tau_{es}$ is the optical depthfor electron scattering. If $\tau_{es} \sim 1$, this average mass is almostcomparable with those of type 1 Seyfert nuclei. However, if $\tau_{es} \ll 1$,as is usually considered, the average mass of type 2 Seyfert nuclei may be moremassive than that of type 1s. We discuss implications for issues concerningboth the current unified model of Seyfert nuclei and physical conditions of theelectron scattering regions.Comment: 21 pages, 2 figures; accepted for Astrophysical Journa