Astron. Astrophys. 360, 213-226 (2000)

5. Summary

1. We have modelled the energy distribution of AB Aur and HD 163296 using an optically thin dust model, and have derived the chemical composition and size distribution of the dust components contributing to the spectrum.

2. The SED of the Herbig Ae stars AB Aur and HD 163296 is characterized by a bi-modal mass over temperature distribution. A low mass ( ) dust component with temperatures of K and a cold component ( K) which contains most of the mass ( to ) is required to fit the SED.

3. The onset of the near-IR emission at 2 µm can be explained with emission from metallic iron grains.

4. In both stars substantial grain growth, compared to interstellar dust, has taken place, resulting in grain sizes up to mm around AB Aur and up to mm around HD 163296.

5. The grain growth around HD 163296 has been more substantial than around AB Aur. Together with the presence of crystalline silicates in the former star, this suggests that HD 163296 is a more evolved system than AB Aur.

© European Southern Observatory (ESO) 2000

Online publication: July 27, 2000
helpdesk.link@springer.de