Astronomy and Astrophysics – Astrophysics
Scientific paper
2004-03-04
Astronomy and Astrophysics
Astrophysics
6 pages, 4 figures, to appear in the ASP proceedings of IAU Symposium 217, "Recycling Intergalactic and Interstellar Matter",
Scientific paper
We discuss HI and optical evidence for ongoing ICM-ISM interactions in 6 HI-deficient Virgo cluster spiral galaxies. One of the clearest cases is the highly inclined Virgo galaxy NGC 4522, which has a normal stellar disk but a truncated gas disk, and lots of extraplanar gas right next to the gas truncation radius in the disk. Unusually strong HI, H-alpha and radio continuum emission are all detected from the extraplanar gas. The radio continuum polarized flux and spectral index peak on the side opposite the extraplanar gas, suggesting ongoing pressure by the ICM. Four other HI-deficient edge-on Virgo spirals show evidence of extraplanar ISM gas or exhibit asymmetries in their disk HI distributions, but contain much less extraplanar HI than NGC 4522. Comparison with recent simulations suggests this difference may be evolutionary, with large surface densities of extraplanar gas observed only in early phases of an ICM-ISM interaction. In NGC 4569, the H-alpha image shows 2 effects of ICM pressure on the galaxy ISM. An anomalous arm of HII regions, possibly extraplanar, emerges from the edge of a truncated H-alpha disk. This resembles the arms seen in simulations which are formed by the combined effects of wind pressure plus rotation. An extended nebulosity near the minor axis, also in the NW, is interpreted as a starburst outflow bubble disturbed by ICM wind pressure.
Crowl Hugh
Kenney Jeffrey D. P.
van Gorkom Jacqueline
Vollmer Bernd
No associations
LandOfFree
Spiral Galaxy - ICM Interactions in the Virgo Cluster does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Spiral Galaxy - ICM Interactions in the Virgo Cluster, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Spiral Galaxy - ICM Interactions in the Virgo Cluster will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-650016