Volume 496, Number 3, March IV 2009
|Page(s)||741 - 749|
|Section||Interstellar and circumstellar matter|
|Published online||30 January 2009|
Model infrared spectra of passively heated proto-planetary disks surrounding intermediate-mass pre-main-sequence stars
Astronomical Institute, University of Amsterdam, Kruislaan 403, 1098 AJ Amsterdam, The Netherlands e-mail: email@example.com
2 Instituut voor Sterrenkunde, Katholieke Universiteit Leuven, Celestijnenlaan 200D, 3001 Leuven, Belgium
3 Astronomical Institute, Utrecht University, Princetonplein 5, 3584 CC Utrecht, The Netherlands
4 Max Planck Institut Für Astronomie, Königstuhl 17, 69117 Heidelberg, Germany
5 Department of Astrophysics/IMAPP, Radboud University Nijmegen, PO Box 9010, 6500 GL Nijmegen, The Netherlands
Accepted: 9 January 2009
Aims. We study theoretical spectra at mid-infrared (5-40 ) wavelengths of proto-planetary disks surrounding intermediate-mass pre-main-sequence stars. Observations show a wide range of spectral shapes and a rich variety in strength and shape of dust resonances. These strong variations in spectral shape reflect differences in the nature and spatial distribution of dust particles in the disk. The aim of this study is to establish what model parameters influence the mid-IR spectra of planet-forming disks.
Methods. A grid of models of passively heated proto-planetary disks is used to calculate the infrared spectrum. We use hydrostatic equilibrium disk models and radiative transfer to calculate the emerging spectrum. We focus on the effects that different disk geometries (flaring, self-shadowed) and dust mineralogy have on the emerging 5-40 spectrum. We adopt four scenarios for the radial and vertical distribution of crystalline silicate dust.
Results. In our model, the 23.5 forsterite band is more sensitive to emission from regions <30 AU, while the 33.5 forsterite band probes regions up to 50 AU. The 23.5 band strength does not depend on the degree of flaring of the disk, while the 33.5 band does. Only models with a substantial abundance (>5 percent) of crystalline silicates at a long distance from the star (>20-50 AU) show detectable emission in the 33.5 forsterite band. The carbon-dust abundance affects the strength of the dust resonances in the 10 spectral region, but not in the 30 region.
Key words: stars: planetary systems: protoplanetary disks / stars: pre-main sequence / stars: circumstellar matter
© ESO, 2009
Current usage metrics show cumulative count of Article Views (full-text article views including HTML views, PDF and ePub downloads, according to the available data) and Abstracts Views on Vision4Press platform.
Data correspond to usage on the plateform after 2015. The current usage metrics is available 48-96 hours after online publication and is updated daily on week days.
Initial download of the metrics may take a while.