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VIVA HI observations of the Virgo spiral galaxy NGC 4501 are presented. The HI disk is sharply truncated to the southwest, well within the stellar disk. A region of low surface-density gas, which is more extended than the main HI disk, is discovered northeast of the galaxy center. These data are compared to existing 6cm polarized radio continuum emission, Halpha, and optical broad band images. We observe a coincidence between the western HI and polarized emission edges, on the one hand, and a faint Halpha emission ridge, on the other. The polarized emission maxima are located within the gaps between the spiral arms and the faint Halpha ridge. Based on the comparison of these observations with a sample of dynamical simulations with different values for maximum ram pressure and different inclination angles between the disk and the orbital plane,we conclude that ram pressure stripping can account for the main observed characteristics. NGC 4501 is stripped nearly edge-on, is heading southwest, and is ~200-300 Myr before peak ram pressure, i.e. its closest approach to M87. The southwestern ridge of enhanced gas surface density and enhanced polarized radio-continuum emission is due to ram pressure compression. It is argued that the faint western Halpha emission ridge is induced by nearly edge-on ram pressure stripping. NGC 4501 represents an especially clear example of early stage ram pressure stripping of a large cluster-spiral galaxy.
Ram pressure stripping of the multiphase ISM is studied in the perturbed Virgo cluster spiral galaxy NGC 4438. This galaxy underwent a tidal interaction ~100 Myr ago and is now strongly affected by ram pressure stripping. Deep VLA radio continuum obs
We present a deep VLA search for HI emission from the low-luminosity Virgo Cluster elliptical galaxy NGC 4476, which contains 1.1 x 10^8 M_sun of molecular gas in an undisturbed disk in regular rotation. No HI was detected. The rms noise in the final
It has been shown that the Virgo spiral galaxy NGC 4330 shows signs of ongoing ram pressure stripping in multiple wavelengths: at the leading edge of the interaction, the Halpha and dust extinction curve sharply out of the disk; on the trailing side,
IRAM 30m 12CO(1-0) and 12CO(2-1) HERA observations are presented for the ram-pressure stripped Virgo spiral galaxy NGC 4522. The CO emission is detected in the galactic disk and the extraplanar gas. The extraplanar CO emission follows the morphology
NGC 4330 is one of the Virgo galaxies whose UV distribution shows a tail structure. An associated tail structure is also observed in the HI and H$alpha$ emission distributions. Previous dynamical modeling showed that the galaxy is approaching the clu