VLA observations of neutral hydrogen in compact groups

VLA images of the neutral hydrogen (HI) in the direction of HCG 2, 16, 33, 88, and 92 (Stephan's Quintet) are examined. In HCG 2 and 16, the HI gas is bound to the individual galaxies but shows definite signs of tidal interaction; while in HCG 92, the more compact configuration, the HI gas is contained within a few prominent cloud features well displaced from the optical positions of any of the spiral members. In every case, the motions of the gas are consistent with the motions of the galaxies within the Hickson groups. A range of kinematical properties is observed for the HI gas, from well-ordered rotation, to small-scale systematic gradients within the cloud features.