CO Depletion and Deuterium Fractionation in Prestellar Cores
- 1 March 2003
- journal article
- Published by American Astronomical Society in The Astrophysical Journal
- Vol. 585 (1) , L55-L58
- https://doi.org/10.1086/374263
Abstract
We report the detection of D2CO in a sample of starless dense cores, in which we previously measured the degree of CO depletion. The deuterium fractionation is found extremely high, [D2CO]/[H2CO] ~ 1-10 %, similar to that reported in low-mass protostars. This provides convincing evidence that D2CO is formed in the cold pre-stellar cores, and later desorbed when the gas warms up in protostars. We find that the cores with the highest CO depletions have also the largest [D2CO]/[H2CO] ratios, supporting the theoretical prediction that deuteration increases with increasing CO depletion.Comment: 11 pages, 2 figures, accepted by ApJ LetterKeywords
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