The HI properties of galaxies in the Coma I cloud revisited

Context. Pre-processing within small groups has been proposed to explain several of the properties of galaxies lying in rich clusters.Aims. The aim of the present work is to see whether pre-processing is acting in the nearby universe, where the structures that are merging to form rich clusters are large and massive.Methods. We study the HI gas properties of a large sample of late-type galaxies belonging to the Coma I cloud, an association of objects close to the Virgo cluster.Results. Contrary to what was previously claimed, late-type galaxies in the Coma I cloud are not deficient in HI gas (HI-def=0.06± 0.44).Conclusions. If the Coma I cloud is representative of infalling groups in nearby clusters, this result suggests that, in the local universe, the evolution of late-type galaxies belonging to loose structures with high velocity dispersions (≥300 kms-1) associated with rich clusters such as Virgo is not significantly perturbed by pre-processing. © 2009 ESO