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On the relative number of Seyfert 1 and Seyfert 2 galaxies and the opening angle of dust torus
Author(s) -
Tovmassian H.M.
Publication year - 2001
Publication title -
astronomische nachrichten
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.394
H-Index - 63
eISSN - 1521-3994
pISSN - 0004-6337
DOI - 10.1002/1521-3994(200106)322:2<87::aid-asna87>3.0.co;2-s
Subject(s) - torus , galaxy , astrophysics , physics , spiral galaxy , mathematics , geometry
It is shown that the samples of Seyfert galaxies used to study different parameters of Seyferts are largely incomplete. The way of estimation of the number of the missed, not detected Seyferts is proposed. It is based on the assumption that distribution of inclinations of Seyferts should be similar to that of spiral galaxies. Addition of the estimated number of the missed Seyferts allows to deduce more correct value of the ratio of numbers of Sy2s to Sy1s, N 2/ N 1. The more real value of the ratio N 2/ N 1 is the one deduced by using the results of counts of bright, nearby Seyferts, and is equal to ∼4. The opening angle of the dust torus is ∼76°.