The search for shock-excited H{sub 2} in Virgo spirals experiencing ram pressure stripping

Journal Article · Mon Mar 10 00:00:00 EDT 2014 · Astrophysical Journal

DOI:https://doi.org/10.1088/0004-637X/783/2/109· OSTI ID:22351569

Wong, O. Ivy ^[1]; Kenney, Jeffrey D. P. ^[2]; Murphy, Eric J. ^[3]; Helou, George ^[4]

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1. CSIRO Astronomy and Space Science, P.O. Box 76, Epping, New South Wales 1710 (Australia)
2. Astronomy Department, Yale University, P.O. Box 208101 New Haven, CT 06520-8101 (United States)
3. Observatories of the Carnegie Institution for Science, 813 Santa Barbara Street, Pasadena, CA 91101 (United States)
4. California Institute of Technology, MC 405-47, 1200 East California Boulevard, Pasadena, CA 91125 (United States)

We investigate the presence of shock-excited H{sub 2} in four Virgo cluster galaxies that show clear evidence of ongoing ram pressure stripping. Mid-infrared spectral mapping of the rotational H{sub 2} emission lines were performed using the Infrared Spectrograph on board the Spitzer Space Telescope. We target four regions along the leading side of galaxies where the intracluster medium appears to be pushing back the individual galaxy's interstellar medium. For comparison purposes, we also study two regions on the trailing side of these galaxies: a region within an edge-on disk and an extraplanar star-forming region. We find a factor of 2.6 excess of warm H{sub 2}/PAH in our sample relative to the observed fractions in other nearby galaxies. We attribute the H{sub 2}/PAH excess to contributions of shock-excited H{sub 2} which is likely to have been triggered by ongoing ram pressure interaction in our sample galaxies. Ram pressure driven shocks may also be responsible for the elevated ratios of [Fe II]/[Ne II] found in our sample.

• OSTI ID: 22351569
• Journal Information: Astrophysical Journal, Vol. 783, Issue 2; Other Information: Country of input: International Atomic Energy Agency (IAEA); ISSN 0004-637X
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTROPHYSICS
COSMOLOGY AND ASTRONOMY
COMPARATIVE EVALUATIONS
EMISSION
EVOLUTION
GALAXIES
GALAXY CLUSTERS
HYDROGEN
INTERACTIONS
POLYCYCLIC AROMATIC HYDROCARBONS
SPACE
STARS
STRIPPING
TELESCOPES