A Phase-space View of Cold-gas Properties of Virgo Cluster Galaxies: Multiple Quenching Processes at Work?

Abstract

We investigate the cold-gas properties of massive Virgo galaxies (>10 9 M ⊙ ) at <3 R 200 ( R 200 is the radius where the mean interior density is 200 times the critical density) on the projected phase-space diagram with the largest archival data set to date to understand the environmental effects on galaxy evolution in the Virgo cluster. We find lower H i and H 2 mass fractions and higher star formation efficiencies (SFEs) from H i and H 2 in the Virgo galaxies than in the field galaxies for matched stellar masses; the Virgo galaxies generally follow the field relationships between the offset from the main sequence of the star-forming galaxies [Δ(MS)] and the gas fractions and SFEs, to the slight offset to lower gas fractions or higher SFEs compared to field galaxies at Δ(MS) < 0; lower gas fractions in galaxies with smaller clustocentric distance and velocity; and lower gas fractions in the galaxies in the W cloud, a substructure of the Virgo cluster. Our results suggest the cold-gas properties of some Virgo galaxies are affected by their environment at least at 3 R 200 maybe via strangulation and/or preprocesses, and H i and H 2 in some galaxies are removed by ram pressure at <1.5 R 200 . Our data cannot rule out the possibility of other processes such as strangulation and galaxy harassment accounting for gas reduction in some galaxies at <1.5 R 200 . Future dedicated observations of a mass-limited complete sample are required for definitive conclusions.