Detection of a large massive circumstellar disk around a high-mass young stellar object in the Carina Nebula

摘要

(abbreviated) We investigate the spatial structure and spectral energydistribution of an edge-on circumstellar disk around an optically invisibleyoung stellar object that is embedded in a dark cloud in the Carina Nebula.Whereas the object was detected as an apparently point-like source in earlierinfrared observations, only the superb image quality (FWHM ~0.5") of our VLT /HAWK-I data could reveal, for the first time, its peculiar morphology. Itconsists of a very red point-like central source that is surrounded by aroughly spherical nebula, which is intersected by a remarkable dark lanethrough the center. We construct the spectral energy distribution of the objectfrom 1 to 870 microns and perform a detailed radiative transfer modeling of thespectral energy distribution and the source morphology. The observed objectmorphology in the near-IR images clearly suggests a young stellar object thatis embedded in an extended, roughly spherical envelope and surrounded by alarge circumstellar disk with a diameter of ~5500 AU that is seen nearlyedge-on. The radiative transfer modeling shows that the central object is amassive (10-15 Msun) young stellar object. The circumstellar disk has a mass ofabout 2 Msun. The disk object in Carina is one of the most massive youngstellar objects for which a circumstellar disk has been detected so far, andthe size and mass of the disk are very large compared to the correspondingvalues found for most other similar objects.