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Title: Velocity mapping and models of the elliptical galaxies NGC 720, NGC 1052, and NGC 4697

Abstract

CCD surface photometry and extensive long-slit spectroscopy are used to construct detailed models of the flattened ellipticals NGC 720, 1052, and 4697. The models are combined with the Jeans equations to yield predicted fields of line-of-sight velocity dispersion and streaming velocity. By comparing these fields with observed velocities, it is concluded that none of these systems can have isotropic velocity dispersion tensors, and diminishing the assumed inclination of any given galaxy tends to decrease the line-of-sight velocity dispersion and, counterintuitively, to increase the line-of-sight rotation speeds. The ratio of the line-of-sight velocity dispersion along the minor axis to that along the major axis is found to be a sensitive diagnostic of the importance of a third integral for the galaxy's structure. 48 refs.

Authors:
; ;  [1]
  1. (Steward Observatory, Tucson, AZ (USA) Oxford Univ. (England) National Optical Astronomy Observatories, Tucson, AZ (USA) California Univ., Santa Cruz (USA))
Publication Date:
OSTI Identifier:
6149718
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal; (USA); Journal Volume: 361
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; GALAXIES; ELLIPTICAL CONFIGURATION; MATHEMATICAL MODELS; MORPHOLOGY; MOTION; PHOTOMETRY; ROTATION; SPECTROSCOPY; STARS; VELOCITY; CONFIGURATION; 640105* - Astrophysics & Cosmology- Galaxies

Citation Formats

Binney, J.J., Davies, R.L., and Illingworth, G.D. Velocity mapping and models of the elliptical galaxies NGC 720, NGC 1052, and NGC 4697. United States: N. p., 1990. Web. doi:10.1086/169169.
Binney, J.J., Davies, R.L., & Illingworth, G.D. Velocity mapping and models of the elliptical galaxies NGC 720, NGC 1052, and NGC 4697. United States. doi:10.1086/169169.
Binney, J.J., Davies, R.L., and Illingworth, G.D. 1990. "Velocity mapping and models of the elliptical galaxies NGC 720, NGC 1052, and NGC 4697". United States. doi:10.1086/169169.
@article{osti_6149718,
title = {Velocity mapping and models of the elliptical galaxies NGC 720, NGC 1052, and NGC 4697},
author = {Binney, J.J. and Davies, R.L. and Illingworth, G.D.},
abstractNote = {CCD surface photometry and extensive long-slit spectroscopy are used to construct detailed models of the flattened ellipticals NGC 720, 1052, and 4697. The models are combined with the Jeans equations to yield predicted fields of line-of-sight velocity dispersion and streaming velocity. By comparing these fields with observed velocities, it is concluded that none of these systems can have isotropic velocity dispersion tensors, and diminishing the assumed inclination of any given galaxy tends to decrease the line-of-sight velocity dispersion and, counterintuitively, to increase the line-of-sight rotation speeds. The ratio of the line-of-sight velocity dispersion along the minor axis to that along the major axis is found to be a sensitive diagnostic of the importance of a third integral for the galaxy's structure. 48 refs.},
doi = {10.1086/169169},
journal = {Astrophysical Journal; (USA)},
number = ,
volume = 361,
place = {United States},
year = 1990,
month = 9
}
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