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CO Depletion and Deuterium Fractionation in Prestellar Cores

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 نشر من قبل Aurore Bacmann
 تاريخ النشر 2003
  مجال البحث فيزياء
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 تأليف Aurore Bacmann




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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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