1. Structure and kinematics of edge-on galaxy discs - I. Observations of the stellar kinematics
- Author
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Kenneth C. Freeman, P. C. van der Kruit, M Kregel, Kapteyn Astronomical Institute, and Astronomy
- Subjects
ABSORPTION-LINE SPECTRA ,Stellar kinematics ,Extinction (astronomy) ,FOS: Physical sciences ,Kinematics ,Astrophysics ,Astrophysics::Cosmology and Extragalactic Astrophysics ,galaxies : kinematics and dynamics ,SURFACE PHOTOMETRY ,VELOCITY DISTRIBUTIONS ,STAR-FORMATION ,GALACTIC DISKS ,3-DIMENSIONAL DISTRIBUTION ,Bulge ,galaxies : fundamental parameters ,ELLIPTIC GALAXIES ,galaxies : structure ,Astrophysics::Galaxy Astrophysics ,SHAPED BULGES ,Physics ,NGC-891 ,Spiral galaxy ,Astrophysics (astro-ph) ,Velocity dispersion ,Astronomy and Astrophysics ,Radius ,Galaxy ,Space and Planetary Science ,galaxies : spiral ,Astrophysics::Earth and Planetary Astrophysics ,SPIRAL GALAXIES - Abstract
We present deep optical long-slit spectra of 17 edge-on spiral galaxies of intermediate to late morphological type, mostly parallel to their major axes and in a few cases parallel to the minor axes.The line-of-sight stellar kinematics are obtained from the stellar absorption lines using the improvedc ross-correlation technique. In general, the stellar kinematics are regular and can be traced well into the disc-dominated region. The mean stellar velocity curves are far from solid-body, indicating that the effect of dust extinction is not large. The line-of-sight stellar disc velocity dispersion correlates with the galaxy maximum rotational velocity, but detailed modeling is necessary to establish whether this represents a physical relation. In four spirals with a boxy- or peanut-shaped bulge we are able to detect asymmetric velocity distributions, having a common signature with projected radius in the mean line-of-sight velocity and the $h_{3}$ and $h_{4}$ curves. In two cases this kinematic asymmetry probably represents the `figure-of-eight' pattern synonymous of a barred potential. We emphasize, however, that the signatures seen in the $h_{3}$ and $h_{4}$ curves may also be due to the disc seen in projection., Comment: Accepted for publication by Mon. Not. R.A.S
- Published
- 2004
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