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arXiv · astro-ph/0702522

HI and OH Absorption toward NGC6240

Willem A. Baan·Yoshiaki Hagiwara·Peter Hofner
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Abstract

VLA observations of large-scale HI and OH absorption in the merging galaxy of NGC6240 are presented with 1 arcsec resolution. HI absorption is found across large areas of the extended radio continuum structure with a strong concentration towards the double-nucleus. The OH absorption is confined to the nuclear region. The HI and OH observations identify fractions of the gas disks of the two galaxies and confirm the presence of central gas accumulation between the nuclei. The data clearly identify the nucleus of the southern galaxy as the origin of the symmetric superwind outflow and also reveal blue-shifted components resulting from a nuclear starburst. Various absorption components are associated with large-scale dynamics of the system including a foreground dust lane crossing the radio structure in the northwest region.

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Willem A. Baan, Yoshiaki Hagiwara, Peter Hofner. 2007-02-20. HI and OH Absorption toward NGC6240. https://doi.org/10.1086/513593

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