A Dynamical Study of Galaxies in the Hickson Compact Groups

Abstract

In order to investigate dynamical properties of spiral galaxies in the Hickson compact groups (HCGs), we present rotation curves of 30 galaxies in 20 HCGs. We found as follows. 1) There is not significant relation between dynamical peculiarity and morphological peculiarity in HCG spirals. 2) There is no significant relation between the dynamical properties and the frequency distribution of nuclear activities in HCG spirals. 3) There are no significant correlations between the dynamical properties of HCG spirals and any group properties (i.e., the size, the velocity dispersion, the galaxy number density, and the crossing time). 4) Asymmetric and peculiar rotation curves are more frequently seen in the HCG spirals than in field spirals and in cluster ones. However, this tendency is more obviously seen in late-type HCG spirals. These results suggest that the dynamical properties of HCG spirals do not strongly correlate with the morphology, the nuclear activity, and the group properties. Our results also suggest that more frequent galaxy collisions occur in the HCGs than in the field and in the clusters.Comment: 24 pages test (aasms4 LaTeX), 50 page tables (aasms4 LaTeX), and 16 Postscript figures, Accepted for The Astronomical Journa