THE CO TULLY-FISHER RELATION FOR THE VIRGO CLUSTER

A comparison between the CO and HI Tully-Fisher relation for a sample of 30 Virgo galaxies shows no significant difference concerning the in trinsic scatter. The distance moduli from both relations after correct ing for the sample incompleteness bias agree within the errors and als o show no significant difference with previous studies of the Virgo cl uster using a complete sample. The CO total linewidth and the CO flux were found to be not well cell-elated. However, if the distances to th e individual galaxies were calculated by the CO Tully-Fisher relation, the CO luminosities calculated using these distances are correlated w ith the CO linewidths. This correlation does not show up when the dist ances were calculated by the conventional HI Tully-Fisher relation. Fi nally we give the structure of the cluster as derived from this small subsample using the distances to the individual galaxies. The large de pth of the cluster is confirmed both by the HI and the CO Tully-Fisher relation.