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arXiv · astro-ph/9612153

Pre-Starbursts in Luminous IR Galaxies ?

Yu Gao·Robert A. Gruendl·K. Y. Lo·C. Y. Hwang·S. Veilleux
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Abstract

We present first results of our on-going BIMA Key Project: imaging the CO(1-0) emission from a sample of 10 luminous IR galaxies (LIRGs) that are at various merging stages, with special emphasis on systems apparently in the early/intermediate stages of merging. We present here CO images with $\sim 5''$ resolution. An important result is the recognition of a plausible pre-starburst phase in some early LIRG mergers (e.g., Arp 302 and NGC 6670). Our initial analysis suggests that a merger-induced starburst phase may not begin before the nuclear separation between the merging galaxies reaches roughly 10 kpc. The surface gas density seems to increase from a few times $10^2 \Msun pc^{-2} to >10^3 \Msun pc^{-2}$ while the prominent CO extent systematically decreases as merging progresses.

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Yu Gao, Robert A. Gruendl, K. Y. Lo, C. Y. Hwang, S. Veilleux. 1996-12-16. Pre-Starbursts in Luminous IR Galaxies ?. https://doi.org/10.1063/1.52748

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