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arXiv · 1712.03256

ALMA Detection of Interstellar Methoxymethanol (CH$_3$OCH$_2$OH)

Brett A. McGuire·Christopher N. Shingledecker·Eric R. Willis·Andrew M. Burkhardt·Samer El-Abd·Roman A. Motiyenko·Crystal L. Brogan·Todd R. Hunter·Laurent Margulès·Jean-Claude Guillemin·Robin T. Garrod·Eric Herbst·Anthony J. Remijan
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Abstract

We report the detection of interstellar methoxymethanol (CH$_3$OCH$_2$OH) in ALMA Bands 6 and 7 toward the MM1 core in the high-mass star-forming region NGC 6334I at ~0.1" - 1" spatial resolution. A column density of 4(2) x $10^{18}$ cm$^{-2}$ at $T_{ex}$ = 200 K is derived toward MM1, ~34 times less abundant than methanol (CH$_3$OH), and significantly higher than predicted by astrochemical models. Probable formation and destruction pathways are discussed, primarily through the reaction of the CH$_3$OH photodissociation products, the methoxy (CH$_3$O) and hydroxymethyl (CH$_2$OH) radicals. Finally, we comment on the implications of these mechanisms on gas-phase vs grain-surface routes operative in the region, and the possibility of electron-induced dissociation of CH$_3$OH rather than photodissociation.

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Brett A. McGuire, Christopher N. Shingledecker, Eric R. Willis, Andrew M. Burkhardt, Samer El-Abd, Roman A. Motiyenko, Crystal L. Brogan, Todd R. Hunter, Laurent Margulès, Jean-Claude Guillemin, Robin T. Garrod, Eric Herbst, Anthony J. Remijan. 2017-12-08. ALMA Detection of Interstellar Methoxymethanol (CH$_3$OCH$_2$OH). https://doi.org/10.3847/2041-8213%2Faaa0c3

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