Related papers: Young massive stars and their environment in the m…
Massive young stellar objects (MYSO) are surrounded by massive dusty envelopes. Our aim is to establish their density structure on scales of ~1000 AU, i.e. a factor 10 increase in angular resolution compared to similar studies performed in…
Massive stars form whilst they are still embedded in dense envelopes. As a result, the roles of rotation, mass loss and accretion in massive star formation are not well understood. This study evaluates the source of the Q-band, lambda=19.5…
The very inner structure of massive young stellar objects (YSOs) is difficult to trace. With conventional observational methods we identify structures still several hundreds of AU in size. However, the (proto-)stellar growth takes place at…
The rarity of young massive stars combined with the fact that they are often deeply embedded has limited the understanding of their formation. Ground based mid-infrared (IR) interferometry is one way of securing the spatial resolution…
We aim to characterize the distribution and composition of circumstellar material around young massive stars, and to investigate exactly which physical structures in these objects are probed by long-baseline mid-infrared interferometric…
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…
The very inner structure of massive YSOs is difficult to trace. With conventional observational methods we often identify structures still several hundreds of AU in size. But we also need information about the innermost regions where the…
[abridged] Our knowledge of the inner structure of embedded massive young stellar objects is still quite limited. We attempt here to overcome the spatial resolution limitations of conventional thermal infrared imaging. We employed…
We report on observations of circumstellar disks around young stars that have been obtained with the MIDI instrument, which is mounted on the VLT Interferometer and operates in the 10 micrometer atmospheric window. The maximum spatial…
The physical structure of the envelopes around a sample of fourteen massive (1000-100,000 solar L) young stars is investigated on 100- 100,000 AU scales using maps and spectra in submillimeter continuum and lines of C17O, CS and H2CO. The…
Information about the inner structure of young stellar objects is crucial for understanding how the central forming stars gain their mass. However, especially for observations of (usually further away) high-mass young stellar objects,…
Deeply embedded and at distances of several kiloparsecs, massive young stellar objects (MYSOs) present numerous challenges for observation and study. In this work, we present spatially-resolved observations of one MYSO, AFGL 4176, together…
We report on resolved interferometric observations with VLTI/MIDI of the massive young stellar object (MYSO) W33A. The MIDI observations deliver spectrally dispersed visibilities with values between 0.03 and 0.06, for a baseline of 45m over…
The rarity and deeply embedded nature of stars with masses larger than 8 solar masses has limited our understanding of their formation. Previous work has shown that complementing spectral energy distributions with interferometric and…
We discuss VLTI AMBER and MIDI interferometry in addition to single-dish Subaru observations of massive young stellar objects. The observations probe linear size scales between 10 to 1000 AU for the average distance of our sources.
We apply mid-infrared spectro-interferometry to the massive young stellar object CRL2136. The observations were performed with the Very Large Telescope Interferometer and the MIDI instrument at a 42m baseline probing angular scales of 50…
This paper examines the density and velocity structure of envelopes around young stellar objects through submillimeter continuum imaging of four objects in Taurus and previously obtained molecular-line data. Observations carried out with…
We review recent advances in our understanding of the innermost regions of the circumstellar environment around young stars, made possible by the technique of long baseline interferometry at infrared wavelengths. Near-infrared observations…
Long-baseline optical interferometers can now detect and resolve hot dust emission thought to arise at the inner edge of circumstellar disks around young stellar objects (YSOs). We argue that the near-infrared sizes being measured are…
The optically invisible infrared-source NGC 2264 IRS 1 is thought to be a massive young stellar object (~10 Msun). Although strong infrared excess clearly shows that the central object is surrounded by large amounts of circumstellar…