Enhanced Deuterium Fractionation in Dense Interstellar Cores Resulting from Multiply Deuterated H
نویسندگان
چکیده
In this Letter, we present the first results from updated models of interstellar deuterium chemistry that now include all possible deuterated isotopomers of . We find that in regions of high density and heavy depletion, such as H3 prestellar cores, the inclusion of HD and D enhances the fractionation of ionic and neutral species significantly. 2 3 Our models are the first to predict the very high atomic D/H ratios (≥0.3) necessary for grain-surface chemistry models to reproduce the high formaldehyde and methanol fractionation seen in star-forming regions. Subject headings: ISM: clouds — ISM: individual (L1544) — ISM: molecules — molecular processes
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