The effects of environment on the molecular and atomic gas properties of large Virgo cluster spirals

The effect of the Virgo environment on the ISM of Virgo disks is presently ascertained by comparing the molecular and atomic gas properties of 40 Virgo cluster spiral galaxies with their optical properties. Virgo Sc galaxies fainter than B(T)exp 0 = 12 are found to have significantly weaker CO emission/unit area and unit mass than brighter Sc galaxies, which have a fairly good correlation between CO luminosity and optical luminosity. An anticorrelation is noted between CO and H I emission in Virgo Sc galaxies with B(T)exp 0 = 11-12. Comparisons of the CO/H I flux ratios with the H I defficiency parameter indicate that there is no CO deficiency in H I-deficient Virgo spirals. 93 refs