Dust Disks around Young Stellar Objects Observations and Models

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Dust Disks around Young Stellar
ObjectsObservations and Models

• Importance of dust disk studies
• Relation to Star and Planet Formation
• Composition and physical condition of dust disk
  strongly linked to star forming processes
• Dust disks deliver prenatal conditions for
  non-gaseous planets like our earth
• Observational advantages
• Easier access for studies of the structure of
  circumstellar disks by observing the dust (in
  comparison to gas observation)
• Available facilities for near- and mid-infrared
  observations
• Study methods
• Extract physical parameters of dust disks by
• Observations Multi-wavelength images, Spectra
  Polarization maps
• Models Production of synthetic observations
• Comparison observation vs. models to allow the
  extraction of physical parameters out of the best
  fitting model
• Interpretation of the extracted parameters by
  comparing different objects

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Modeling Principle

• Monte Carlo radiative transfer 3D simulation of
  static dust disk
• Input
• Disk geometry
• Density structure
• Dust grain size distribution
• Temperature profile
• Star parameters
• Dust grain chemistry
• Output
• Multi-wavelength images
• Spectral energy
• distribution
• Polarization maps

Reflected star light
Direct star light
Reemission from dust disk
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Comparison example IRAS04158
1.3mm

• amax 2.0?m
• mdisk 1.510-4M?
• rout 1120AU
• and other parameters describing
• Geometry
• Density distribution
• Dust grain settling and composition

1.6mm
2.2mm
Observation
Model