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Interstellar triply deuterated ammonia

Floris F. S. van der Tak·Dariusz C. Lis·Maryvonne Gerin·Evelyne Roueff·Peter Schilke·Tom G. Phillips
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Abstract

Research on interstellar ND3 is reviewed and updated from the discovery papers. Results from observations of a dozen sources at centimeter and submillimeter wavelengths are presented. The two data sets are consistent, but do not constrain the excitation conditions in the ND3-emitting gas. The column density ratios of NH3:NH2D, NH2D:ND2H and ND2H:ND3, observed in similar sized beams, are ~10, and present a challenge for both the gas-phase and the grain-surface chemistry scenarios of deuterium fractionation. The role of shocks and of CO depletion in deuterium chemistry is discussed.

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Floris F. S. van der Tak, Dariusz C. Lis, Maryvonne Gerin, Evelyne Roueff, Peter Schilke, Tom G. Phillips. 2002-12-13. Interstellar triply deuterated ammonia. https://arxiv.org/abs/astro-ph/0212324

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