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VLA HI and OVRO CO Interferometry of a Tidal Dwarf Galaxy

Elias Brinks·Pierre-Alain Duc·Fabian Walter
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Abstract

We present high resolution interferometric observations of the cool atomic and cold molecular ISM of the TDG candidate Arp 245N, an object resembling a dwarf galaxy in the northern tidal tail of the interacting system NGC 2992/3. We observed the HI line with the NRAO VLA and the CO(1-->0) transition with the OVRO millimeter interferometer at 5''-6'' angular resolution (750 pc linear resolution). These datacubes offer the required spatial and velocity resolution to determine whether the mass concentration near the tip of the tail is a genuine feature, and hence a good TDG candidate, or an artefact caused by a fortuitous alignment of our line of sight with the direction of the tail. A preliminary analysis seems to confirm that Arp 245N is a self-gravitating entity.

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Elias Brinks, Pierre-Alain Duc, Fabian Walter. 2004-02-12. VLA HI and OVRO CO Interferometry of a Tidal Dwarf Galaxy. https://arxiv.org/abs/astro-ph/0402274

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