Environmental Effects on Gaseous Disks of the Virgo Spiral Galaxies

Abstract

We found high molecular fractions ($f_{\mathrm{mol}}$; ratio of the molecular to total gas surface densities) in three of five Virgo spiral galaxies in spite of their low total gas column density, based on ${}^{12}$CO$(J=1-0)$ observations with the Nobeyama 45 m telescope equipped with a multi-beam receiver, BEARS. We interpret this as a result of environmental effects. Combining the CO data with HI data, the relationship between the surface density of the total gas (HI plus H${}_2$) and $f_{\mathrm{mol}}$ indicates that the three galaxies near the cluster center have larger $f_{\mathrm{mol}}$ values than expected for field galaxies, while the others show normal $f_{\mathrm{mol}}$. The large $f_{\mathrm{mol}}$ is interpreted as being due either to effective HI gas stripping, even in the inner disks, or to large ISM pressure induced by the high ICM pressure and/or ram pressure, although the possibility of an unusually high metallicity cannot be ruled out.

12 pages, 8 figures. To appear in ApJ

Cited by in corpus (10)

• The JCMT Nearby Galaxies Legacy Survey I. Star Forming Molecular Gas in Virgo Cluster Spiral Galaxies
• NGC 4254: An Act of Harassment Uncovered by the Arecibo Legacy Fast ALFA Survey
• CO Multi-line Imaging of Nearby Galaxies (COMING) IV. Overview of the Project
• Cosmic Magnetism in Centimeter and Meter Wavelength Radio Astronomy
• A universal correlation between star-formation activity and molecular gas properties across environments
• The AGN fuelling/feedback cycle in nearby radio galaxies - V. The cold atomic gas of NGC 3100 and its group
• FOREST unbiased Galactic plane imaging survey with the Nobeyama 45 m telescope (FUGIN). VII. molecular fraction of HI clouds
• Molecular Fraction in the Galactic Center: The Central Molecular and HI Zones
• Gas properties as a function of environment in the proto-supercluster Hyperion at z ~ 2.45
• Static Pressure of Hot Gas: Its Effect on the Gas Disks of Galaxies