Volume 389, Number 1, July I 2002
|Page(s)||L6 - L10|
|Published online||14 June 2002|
Letter to the Editor
The degree of CO depletion in pre-stellar cores*
Astrophysikalisches Institut und Universitäts Sternwarte (AIU), Schillergäßchen 2-3, 07745 Jena, Germany e-mail: firstname.lastname@example.org
2 Laboratoire d'Astrophysique, Observatoire de Grenoble, BP 53, 38041 Grenoble Cedex 9, France e-mail: email@example.com
3 Observatoire de Bordeaux, 2 rue de l'Observatoire, BP 89, 33270 Floirac, France e-mail: firstname.lastname@example.org,email@example.com
4 Instituto de Astronomía, Universidad Nacional Autónoma de México, Apartado Postal 3-72 (Xangari), 58089 Morelia, Michoacán, Mexico e-mail: firstname.lastname@example.org
Corresponding author: A. Bacmann, email@example.com
Accepted: 24 April 2002
We present new results on CO depletion in a sample of nearby pre-stellar cores, based on observations of the millimeter C17O and C18O lines and the 1.3 mm dust emission with the IRAM 30 m telescope. In most cases, the distribution of CO is much flatter than that of the dust, whereas other tracers, like , still probe the latter. In the centre of these objects, we estimate CO to be underabundant by a factor 4–15 depending on the cores. The CO underabundance is more pronounced in the central regions and appears to decrease with increasing distance from the core centre. This underabundance is most likely due to the freezing out of CO onto the dust grains in the cold, dense parts of the cores. We find evidence for an increase of the CO depletion degree with the core density.
Key words: ISM: molecules / dust, extinction / stars: formation
© ESO, 2002
Current usage metrics show cumulative count of Article Views (full-text article views including HTML views, PDF and ePub downloads, according to the available data) and Abstracts Views on Vision4Press platform.
Data correspond to usage on the plateform after 2015. The current usage metrics is available 48-96 hours after online publication and is updated daily on week days.
Initial download of the metrics may take a while.