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Ices in Star-Forming Regions: First Results from VLT-ISAAC

E. F. van Dishoeck·E. Dartois·W. F. Thi·L. d'Hendecourt·A. G. G. M. Tielens·P. Ehrenfreund·W. A. Schutte·K. Pontoppidan·K. Demyk·J. Keane·A. C. A. Boogert
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Abstract

The first results from a VLT-ISAAC program on L- and M-band infrared spectroscopy of deeply-embedded young stellar objects are presented. The advent of 8-m class telescopes allows high S/N spectra of low-luminosity sources to be obtained. In our first observing run, low- and medium-resolution spectra have been measured toward a dozen objects, mostly in the Vela and Chamaeleon molecular clouds. The spectra show strong absorption of H2O and CO ice, as well as weak features at `3.47' and 4.62 mu. No significant solid CH3OH feature at 3.54 mu is found, indicating that the CH3OH/H2O ice abundance is lower than toward some massive protostars. Various evolutionary diagnostics are investigated for a set of sources in Vela.

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E. F. van Dishoeck, E. Dartois, W. F. Thi, L. d'Hendecourt, A. G. G. M. Tielens, P. Ehrenfreund, W. A. Schutte, K. Pontoppidan, K. Demyk, J. Keane, A. C. A. Boogert. 2001-10-20. Ices in Star-Forming Regions: First Results from VLT-ISAAC. https://doi.org/10.1007/10856518_30

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