CO depletion and deuterium fractionation in prestellar cores

被引:169
作者
Bacmann, A
Lefloch, B
Ceccarelli, C
Steinacker, J
Castets, A
Loinard, L
机构
[1] European So Observ, D-85748 Garching, Germany
[2] Inst Astrophys, D-07745 Jena, Germany
[3] Univ Sternwarte, D-07745 Jena, Germany
[4] Observ Grenoble, Astrophys Lab, F-38041 Grenoble, France
[5] Observ Bordeaux, F-33270 Floirac, France
[6] Univ Nacl Autonoma Mexico, Inst Astron, Morelia 58089, Michoacan, Mexico
关键词
ISM : abundances; ISM : molecules; stars : formation;
D O I
10.1086/374263
中图分类号
P1 [天文学];
学科分类号
0704 ;
摘要
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 to be extremely high, [D2CO]/[H2CO] similar to 1%-10%, similar to that reported in low-mass protostars. This provides convincing evidence that D2CO is formed in the cold prestellar 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.
引用
收藏
页码:L55 / L58
页数:4
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