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Title: Kinematics and ionization of extended gas in active galaxies. III. The extranuclear properties of NGC 1068

Abstract

The kinematic and ionization structure of the extranuclear gas of the Seyfert 2 galaxy NGC 1068 has been investigated using a grid of 28 high- and seven low-dispersion long-slit spectra. The velocity field of most of the gas more than 15 arcsec from the nucleus is well described by a rotating disk with an approximately flat rotation curve. The kinematic line of nodes coincides with the major axis of the outermost continuum light, and the disk inclination derived from the axial ratio of the outer isophotes and the kinematic fit are broadly consistent. The progressive change of the position angle of the major axes of the brighter isophotes are evidently due to a superposition of oval or barlike distortions in the galactic plane. The observed ionization structure of the gas can be understood as a mixture of two disk components projected on top of each other. Much of the ionization pattern in the other disk may result from partial beaming of the ionizing continuum radiation as it escapes from the nucleus. 60 references.

Authors:
; ;
Publication Date:
Research Org.:
Observatorio Interamericano de Cerro Tololo, La Serena, Chile; Cambridge Univ., England; Maryland Univ., College Park; Virginia Univ., Charlottesville; Steward Observatory, Tucson, AZ
OSTI Identifier:
5966387
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophys. J.; (United States); Journal Volume: 319
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; SEYFERT GALAXIES; COSMIC GASES; BALMER LINES; EMISSION SPECTRA; GALAXY NUCLEI; IONIZATION; FLUIDS; GALAXIES; GASES; SPECTRA; 640105* - Astrophysics & Cosmology- Galaxies

Citation Formats

Baldwin, J.A., Wilson, A.S., and Whittle, M.. Kinematics and ionization of extended gas in active galaxies. III. The extranuclear properties of NGC 1068. United States: N. p., 1987. Web. doi:10.1086/165435.
Baldwin, J.A., Wilson, A.S., & Whittle, M.. Kinematics and ionization of extended gas in active galaxies. III. The extranuclear properties of NGC 1068. United States. doi:10.1086/165435.
Baldwin, J.A., Wilson, A.S., and Whittle, M.. Sat . "Kinematics and ionization of extended gas in active galaxies. III. The extranuclear properties of NGC 1068". United States. doi:10.1086/165435.
@article{osti_5966387,
title = {Kinematics and ionization of extended gas in active galaxies. III. The extranuclear properties of NGC 1068},
author = {Baldwin, J.A. and Wilson, A.S. and Whittle, M.},
abstractNote = {The kinematic and ionization structure of the extranuclear gas of the Seyfert 2 galaxy NGC 1068 has been investigated using a grid of 28 high- and seven low-dispersion long-slit spectra. The velocity field of most of the gas more than 15 arcsec from the nucleus is well described by a rotating disk with an approximately flat rotation curve. The kinematic line of nodes coincides with the major axis of the outermost continuum light, and the disk inclination derived from the axial ratio of the outer isophotes and the kinematic fit are broadly consistent. The progressive change of the position angle of the major axes of the brighter isophotes are evidently due to a superposition of oval or barlike distortions in the galactic plane. The observed ionization structure of the gas can be understood as a mixture of two disk components projected on top of each other. Much of the ionization pattern in the other disk may result from partial beaming of the ionizing continuum radiation as it escapes from the nucleus. 60 references.},
doi = {10.1086/165435},
journal = {Astrophys. J.; (United States)},
number = ,
volume = 319,
place = {United States},
year = {Sat Aug 01 00:00:00 EDT 1987},
month = {Sat Aug 01 00:00:00 EDT 1987}
}
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