An Investigation into the Geometry of Seyfert Galaxies

C. J. Clarke; A. L. Kinney; J. E. Pringle

doi:10.1086/305285

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An Investigation into the Geometry of Seyfert Galaxies

C. J. Clarke·A. L. Kinney·J. E. Pringle

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Abstract

We present a new method for the statistical investigation into the distributions of the angle beta between the radio axis and the normal to the galactic disk for a sample of Seyfert galaxies. We discuss how further observations of the sample galaxies can strengthen the conclusions. Our data are consistent with the hypothesis that AGN jets are oriented randomly in space, independent of the position of the plane of the galaxy. By making the simple assumption that the Standard Model of AGN holds, with a universal opening angle of the thick torus of phi_c, we demonstrate a statistical method to obtain an estimate of phi_c. Our data are not consistent with the simple-minded idea that Seyfert 1s and Seyfert 2s are differentiated solely by whether or not our line of sight lies within some fixed angle of the jet axis. Our result is significant on the 2 sigma level and can thus be considered only suggestive, not conclusive. A complete sample of Seyfert galaxies selected on an isotropic property is required to obtain a conclusive result.

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C. J. Clarke, A. L. Kinney, J. E. Pringle. 1997-09-15. An Investigation into the Geometry of Seyfert Galaxies. https://doi.org/10.1086/305285

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