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CO Depletion and Deuterium Fractionation in Prestellar Cores

Aurore Bacmann·Bertrand Lefloch·Cecilia Ceccarelli·Juergen Steinacker·Alain Castets·Laurent Loinard
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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.

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Aurore Bacmann, Bertrand Lefloch, Cecilia Ceccarelli, Juergen Steinacker, Alain Castets, Laurent Loinard. 2003-01-31. CO Depletion and Deuterium Fractionation in Prestellar Cores. https://doi.org/10.1086/374263

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