NASA/IPAC EXTRAGALACTIC DATABASE
Date and Time of the Query: 2019-08-20 T22:53:54 PDT
Help | Comment | NED Home

For refcode 2000ApJ...528..179M:
Retrieve 45 NED objects in this reference.
Please click here for ADS abstract

NED Abstract

Copyright by American Astronomical Society. Reproduced by permission
2000ApJ...528..179M New Mid-Infrared Diagnostic of the Dusty Torus Model for Seyfert Nuclei Takashi Murayama Astronomical Institute, Graduate School of Science, Tohoku University, Aoba, Sendai 980-8578, Japan; murayama@astr.tohoku.ac.jp Hideaki Mouri Meteorological Research Institute, 1-1 Nagamine, Tsukuba 305-0052, Japan; hmouri@mri-jma.go.jp and Yoshiaki Taniguchi Astronomical Institute, Graduate School of Science, Tohoku University, Aoba, Sendai 980-8578, Japan; tani@astr.tohoku.ac.jp Received 1998 January 30; accepted 1999 August 16 ABSTRACT We propose a new diagnostic of the "dusty torus" model for Seyfert nuclei. Dust grains in the torus are heated by the nuclear continuum and reradiate mostly in the mid-infrared wavelengths. From the geometry of the torus, it is predicted that the emission at {lambda} <= 10 microns has strong dependence on the viewing angle. Since the dependence is predicted to be insignificant at {lambda} >= 10 microns, we study the flux ratio between 3.5 micron (L band) and 25 micron; R(L, 25) = log[({nu}_3.5 micron_ S_{nu}3.5 micron)/({nu}_25 micron S_{nu}25 micron_)]. In three different samples (optically selected, X-ray-selected, and infrared-selected samples) of Seyfert galaxies, the observed values of R(L, 25) between type 1 Seyfert galaxies (S1's) and type 2 Seyfert galaxies (S2's) are found to be clearly separated; R(L, 25) > -0.6 for S1's while R(L, 25) < -0.6 for S2's. This implies universality of their torus properties. With this result and the other observational characteristics, we investigate the most plausible torus model among those presented in Pier & Krolik. Subject headings: galaxies: ISM-galaxies: Seyfert-infrared: galaxies
Retrieve 45 NED objects in this reference.
Please click here for ADS abstract

Back to NED Home