Astronomy and Astrophysics, volume 310, 75-92 (1996/6-1)
Disk structure and kinematics of S0 galaxies.
SEIFERT W. and SCORZA C.
Abstract (from CDS):
The photometric and kinematic structure of 15 nearly edge-on S0 galaxies and one bulge dominated spiral galaxy has been investigated on the basis of a decomposition method applied to CCD data. The method consists in the construction of a bulge model by masking the isophote region affected by the disk. The subtraction of this model yields the surface brightness distribution of the disk. It has been found that a significant number of the objects possess two disks: the main, outer disk having an inner cut-off and a steeper inner disk. The radial run of the a4/a parameter (which shows two or three maxima) supports this finding. Wiggles in the rotation curve of the galaxies are clearly connected to the observed two-disk structure. They are not caused by intrinsically peculiar kinematics of the objects, but simply by the superposition of the (hot) bulge component and the two (cold) disk components. In several objects we find ring-like structures. These are located near the turnover radius of the rotation curve.