Are the nuclei of Seyfert 2 galaxies viewed face-on?

Citation
Ka. Weaver et Cs. Reynolds, Are the nuclei of Seyfert 2 galaxies viewed face-on?, ASTROPHYS J, 503(1), 1998, pp. L39-L43
Citations number
19
Categorie Soggetti
Space Sciences
Journal title
ASTROPHYSICAL JOURNAL
ISSN journal
0004637X → ACNP
Volume
503
Issue
1
Year of publication
1998
Part
2
Pages
L39 - L43
Database
ISI
SICI code
0004-637X(19980810)503:1<L39:ATNOS2>2.0.ZU;2-H
Abstract
We show from modeling the Fe K alpha line in the ASCA spectra of four X-ray -bright narrow emission line galaxies (Seyfert types 1.9 and 2) that two eq ually viable physical models can describe the observed line profile. The fi rst is discussed by Turner et al, and consists of emission from a nearly po le-on accretion disk. The second, which is statistically preferred, is a su perposition of emission from an accretion disk viewed at an intermediate in clination of similar to 48 degrees and a distinct, unresolved feature that presumably originates some distance from the galaxy nucleus. The intermedia te inclination is entirely consistent with unified schemes, and our finding s challenge recent assertions that Seyfert 2 galaxies are preferentially vi ewed with their inner regions face-on. We derive mean equivalent widths for the narrow and disk lines of [EWN] = 60 eV and [EWD] = 213 eV, respectivel y. The X-ray data are well described by a geometry in which our view of the active nucleus intersects and is blocked by the outer edges of the obscuri ng torus and therefore do not require severe misalignments between the accr etion disk and the torus.