Dusty Tori of Seyfert Nuclei
نویسندگان
چکیده
Dusty tori around active galactic nuclei (AGNs) play an important role in the classification of Seyfert galaxies. (Antonucci & Miller 1985; see also Antonucci 1993 for a review). Seyfert galaxies observed from a face-on view of the torus are recognized as type 1 Seyferts (S1s) while those observed from an edge-on view are recognized as type 2 Seyferts (S2s). Therefore, physical properties of dusty tori are of great interest. We briefly introduce three statistical studies investigating properties of dusty tori; 1) physical sizes of dusty tori based on water-vapor maser emission (Taniguchi & Murayama 1998), 2) ionization condition of the inner wall of tori based on high-ionization emission lines (Murayama & Taniguchi 1998a,b), and 3) viewing angle toward dusty tori based on mid-infrared color (Murayama, Mouri, & Taniguchi 2000). Please see references for detailed discussion.
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