Rotation curves of Hickson compact group galaxies from Fabry-Perot Hα velocity fields

We present the first results of a survey of Her images taken with a Fabry Perot instrument for 26 spiral galaxies in Hickson compact groups. We find that over 2/3 of the compact-group galaxies in our sample have normal-shaped rotation patterns, with matching rotation curves for the approaching and receding sides. The remaining galaxies present peculiar kinematics. A fine tunning of some of the kinematically-derived galaxy parameters (such as centers, inclinations and position angles) was necessary in order to obtain meaningful rotation curves. Such a fine tunning of parameters can only be achieved when velocity fields are available, since photometrically derived parameters can differ significantly from those derived using the velocity maps. This explains the disagreement between our results and previous long-slit determinations (Rubin et al. 1991) which concluded that most Hickson compact group galaxies had rotation curves with highly distorted shapes and/or anomalous amplitudes.