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arXiv · 0712.0301

An infrared view of (candidate accretion) disks around massive young stars

A. Bik·A. Lenorzer·W-. F. Thi·E. Puga-Antolin·L. B. F. M. Waters·L. Kaper·L. N. Martin-Hernandez
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Abstract

Near-infrared surveys of high-mass star-forming regions start to shed light onto their stellar content. A particular class of objects found in these regions, the so-called massive Young Stellar Objects (YSOs) are surrounded by dense circumstellar material. Several near- and mid-infrared diagnostic tools are used to infer the physical characteristics and geometry of this circumstellar matter. Near-infrared hydrogen emission lines provide evidence for a disk-wind. The profiles of the first overtone of the CO band-heads, originating in the inner 10 AU from the central star, are well fitted assuming a keplerian rotating disk. The mid-infrared spectral energy distribution requires the presence of a more extended envelope containing dust at a temperature of about 200 K. CRIRES observations of CO fundamental absorption lines confirm the presence of a cold envelope. We discuss the evolutionary status of these objects.

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A. Bik, A. Lenorzer, W-. F. Thi, E. Puga-Antolin, L. B. F. M. Waters, L. Kaper, L. N. Martin-Hernandez. 2007-12-03. An infrared view of (candidate accretion) disks around massive young stars. https://arxiv.org/abs/0712.0301

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