Volume 427, Number 3, December I 2004
|Page(s)||L13 - L16|
|Published online||16 November 2004|
Letter to the Editor
Evidence for an inner molecular disk around massive Young Stellar Objects*
Astronomical Institute “Anton Pannekoek”, University of Amsterdam, Kruislaan 403, 1098 SJ Amsterdam, The Netherlands e-mail: firstname.lastname@example.org
Accepted: 2 October 2004
We present observations of CO overtone bandhead emission toward four massive Young Stellar Objects (spectral type O6–B5). The high signal-to-noise ratio K-band spectra were obtained with VLT-ISAAC at a resolution km s-1, sufficient to resolve the bandheads, but not the individual J-lines. We are able to explain the shape of the lines by assuming a simple isothermal Keplerian disk model seen at different inclinations. The gas temperature ranges from 1500 to 4500 K and the CO column density is between 0.1 and cm-2. The emission probably arises within the first few astronomical units of the disk, consistent with the high gas temperature. Our results indicate that molecules can survive close to a hot star and suggest that dense ( cm-3) inner disks may be relatively common at an advanced stage of high-mass star formation.
Key words: stars: early-type, formation / circumstellar matter / molecular processes / line: profiles
© ESO, 2004
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.