Research Note

The HI properties of galaxies in the Coma I cloud revisited

¹ Laboratoire d'Astrophysique de Marseille, UMR 6110 CNRS, 38 rue F. Joliot-Curie, 13388 Marseille, France e-mail: Alessandro.Boselli@oamp.fr
² Universita degli Studi di Milano-Bicocca, Piazza delle Scienze 3, 20126 Milano, Italy e-mail: Giuseppe.Gavazzi@mib.infn.it

Received: 9 June 2009
Accepted: 19 September 2009

Abstract

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 ().

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 km s^-1) associated with rich clusters such as Virgo is not significantly perturbed by pre-processing.