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arXiv · 1907.13551

Interstellar Glycolaldehyde, Methyl Formate, and Acetic Acid I: A Bi-modal Abundance Pattern in Star Forming Regions

Samer J. El-Abd·Crystal L. Brogan·Todd R. Hunter·Eric R. Willis·Robin T. Garrod·Brett A. McGuire
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Abstract

The relative column densities of the structural isomers methyl formate, glycolaldehyde, and acetic acid are derived for a dozen positions towards the massive star-forming regions MM1 and MM2 in the NGC 6334I complex, which are separated by $\sim$4000 AU. Relative column densities of these molecules are also gathered from the literature for 13 other star-forming regions. In this combined dataset, a clear bi-modal distribution is observed in the relative column densities of glycolaldehyde and methyl formate. No such distribution is evident with acetic acid. The two trends are comprised of star-forming regions with a variety of masses, suggesting that there must be some other common parameter that is heavily impacting the formation of glycolaldehyde. This is indicative of some demonstrable differentiation in these cores; studying the abundances of these isomers may provide a clue as to the integral chemical processes ongoing in a variety of protostellar environments.

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Samer J. El-Abd, Crystal L. Brogan, Todd R. Hunter, Eric R. Willis, Robin T. Garrod, Brett A. McGuire. 2019-07-31. Interstellar Glycolaldehyde, Methyl Formate, and Acetic Acid I: A Bi-modal Abundance Pattern in Star Forming Regions. https://doi.org/10.3847/1538-4357%2Fab3646

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