Astron. Astrophys. Suppl. Ser. 145, 71-82

Line-of-sight velocity distributions of 53 early-type galaxies

W. Koprolin - W.W. Zeilinger

Send offprint request: W. Koprolin

Institut für Astronomie der Universität Wien, Türkenschanzstraße 17, A-1180 Wien, Austria

Received December 1, 1999; accepted April 20, 2000

Abstract:

55 long-slit spectra of 53 early-type galaxies were observed at La Silla/ESO and reduced using standard methods. The line-of-sight velocity distributions (LOSVDs) were measured using the fourier quotient method and the fourier fitting method as described by van der Marel et al. (1993). 32% of the examined galaxies contain kinematically decoupled stellar omponents, the size of these cores was 0.40 $\pm$ 0.28 kpc, in each case the core was smaller than 1 kpc. Analysis of the kinematics reveals in 49% of the sample galaxies the signature of a stellar disk component, in 15% this is uncertain. There is evidence that the phenomenon of kinematically decoupled components is present in the whole class of early-type galaxies. Several correlations between photometric and kinematic parameters like the $(v/\sigma )^*$ vs. $\epsilon$ diagram, the anisotropy - luminosity correlation or $\kappa$-space were as well examined using measurement results for spectroscopic data and photometric data out of literature. It is also shown that those sample galaxies with kinematically decoupled components are more likely to be found in groups of high density, strengthening the assumption that such components are remnants of merging events.

Key words: galaxies: elliptical and lenticular -- galaxies: fundamental parameters -- galaxies: kinematics and dynamics