AAS 204th Meeting, June 2004
Session 80 Nearby Galaxies
Poster, Thursday, June 3, 2004, 9:20am-4:00pm, Ballroom

[Previous] | [Session 80] | [Next]

[80.12] Dense Cloud Ablation During Ram Pressure Stripping of the Virgo Spiral NGC 4402

H.H. Crowl, J.D.P. Kenney (Yale University), J.H. van Gorkom (Columbia University), B. Vollmer (CDS, Strasbourg)

We present optical, HI and radio continuum observations of ongoing ram-pressure stripping and dense cloud ablation in the Virgo edge-on Sc galaxy NGC 4402. VLA HI and radio continuum maps show a truncated gas disk and extraplanar emission to the NW of the plane of the galaxy. The H\alpha image shows many HII complexes along the SE edge of the disk, presumably star formation triggered by the ICM pressure. Optical B, V, and R images at 0.5" resolution taken with the WIYN telescope show a remarkable dust lane morphology: the dust lane of the galaxy curves up and out of the disk, matching the HI morphology. To the south of the main ridge of interstellar material, where the galaxy is relatively clean of gas and dust, we have discovered remarkable linear dust filaments with a position angle of 40\circ. This position angle matches extraplanar radio continuum emission edges; we interpret this angle as the projected ICM wind direction. One of the observed dust filaments has an HII region at its head. We interpret these dust filaments as dense clouds which were initially left behind as the low-density ISM is stripped, but then are ablated by the ICM. These results provide striking new evidence on the fate of molecular clouds of cluster galaxies as they are stripped of their ISM.

[Previous] | [Session 80] | [Next]

Bulletin of the American Astronomical Society, 36 #2
© YEAR. The American Astronomical Soceity.