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arXiv · 1503.05254

Highly efficient star formation in NGC 5253 possibly from stream-fed accretion

J. L. Turner·S. C. Beck·D. J. Benford·S. M. Consiglio·P. T. P. Ho·A. Kovács·D. S. Meier·J. -H. Zhao
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Abstract

A local dwarf galaxy, NGC 5253, has a young super star cluster that may provide an example of highly efficient star formation. Here we report the detection and imaging, with the Submillimeter Array, of the J= 3-2 rotational transition of CO at the location of the massive cluster associated with the supernebula. The gas cloud is hot, dense, quiescent, and extremely dusty. Its gas-to-dust ratio is lower than the Galactic value, which we attribute to dust enrichment by Wolf-Rayet stars within the embedded star cluster. Its star formation efficiency exceeds 50%, ten times higher than clouds in the Milky Way: this cloud is a factory of stars and soot. We suggest that high efficiency results from the force-feeding of star formation by a streamer of gas falling into the galaxy.

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J. L. Turner, S. C. Beck, D. J. Benford, S. M. Consiglio, P. T. P. Ho, A. Kovács, D. S. Meier, J. -H. Zhao. 2015-03-18. Highly efficient star formation in NGC 5253 possibly from stream-fed accretion. https://doi.org/10.1038/nature14218

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