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Deep Effelsberg 100-m HI observations of 5 HI deficient Virgo spiral galaxies are presented. No new extended HI tail is found in these galaxies. The already known HI tail north of NGC 4388 does not significantly extend further than a WSRT image has shown. Based on the absence of HI tails in a sample of 6 Virgo spiral galaxies and a balance of previous detections of extraplanar gas in the targeted galaxies we propose a global picture where the outer gas disk (beyond the optical radius R_25) is removed much earlier than expected by the classical ram pressure criterion. Based on the two-phase nature of atomic hydrogen located in a galactic disk, we argue that the warm diffuse HI in the outer galactic disk is evaporated much more rapidly than the cold dense HI. Therefore, after a ram pressure stripping event we can only observe atomic hydrogen which was cold and dense before it was removed from the galactic disk. This global picture is consistent with all available observations. We detect between 0.3% and 20% of the stripped mass assuming an initially non-deficient galaxy and between 3% and 70% of the stripped mass assuming an initially HI deficient galaxy (def=0.4). Under the latter assumption we estimate an evaporation rate by dividing the missing mass by the estimated time to peak ram pressure from dynamical simulations. We find evaporation rates between 10 and 100 M_solar/yr.
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 4654 is a Virgo galaxy seen almost face-on, which undergoes nearly edge-on gas ram pressure stripping and a fly-by gravitational interaction with another massive galaxy, NGC 4639. NGC 4654 shows a strongly compressed gas region near the outer edg
We investigate the effects of ram pressure on the molecular ISM in the disk of the Coma cluster galaxy NGC 4921, via high resolution CO observations. We present 6 resolution CARMA CO(1-0) observations of the full disk, and 0.4 resolution ALMA CO(2-1)
We present IRAM 30m sensitive upper limits on CO emission in the ram pressure stripped dwarf Virgo galaxy IC3418 and in a few positions covering HII regions in its prominent 17 kpc UV/Ha gas-stripped tail. In the central few arcseconds of the galaxy,
The diffuse ionized gas (DIG) is an important component of the interstellar medium and it can be affected by many physical processes in galaxies. Measuring its distribution and contribution in emission allows us to properly study both its ionization