H. Awaki, K. Koyama, H. Inoue and J.P. Halpern

Abstract

Sixteen Seyfert galaxies, including 9 Seyfert 2 galaxies, were observed with the Ginga satellite. Thirteen of the Seyfert galaxies in the sample have been detected, and the Fe line and K-edge structure for these galaxies investigated. Twelve of the 13 detected galaxies also have a detected Fe line. The equivalent width of a Seyfert 1 galaxy is distributed around a mean value of about 173 eV, with a standard deviation of about 40 eV; that for a Seyfert 2 galaxy is scattered from less than 80 eV to 1300 eV. Most of the detected galaxies show an absorption feature at the energy of the iron K-edge. The iron column density determined from the iron K-edge structure ranges from less than 10 to the 17.5th/sq cm to 2 x 10 to the 19th/sq cm. Using a Monte Carlo simulation, it is found that isotropic X-ray emission within a uniformly distributed gas cannot explain the observed result. The overall distribution of the iron line and the K-edge intensity for all of the galaxies in the sample could be reproduced by using an accretion torus model with a single parameter: the viewing angle of the active galactic nucleus within a accretion torus.