An Inner Molecular Bar or Disk in NGC 5195

S. Aalto; G. Rydbeck

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arXiv · astro-ph/0107590

An Inner Molecular Bar or Disk in NGC 5195

S. Aalto·G. Rydbeck

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Abstract

High resolution OVRO CO 1-0 observations of the inner kpc of the M51-companion NGC 5195 reveal the presence of a kpc-sized bar, or possibly an inclined disk with a two armed spiral, at the center of the optical bar. The molecular mass of the feature is 2.7 x 10^8 M_o, half of which is within a radius of 250 pc. The resulting gas surface density of 10^3 M_o pc^-2 is typical for starbursts. However, the lack of evidence for current star formation suggests that either some mechanism is preventing stars from forming, or the standard CO to H_2 conversion factor substantially overestimates the available amounts of molecular gas.

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S. Aalto, G. Rydbeck. 2001-07-31. An Inner Molecular Bar or Disk in NGC 5195. https://arxiv.org/abs/astro-ph/0107590

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