Cool Stars 14 - Submitted Abstract # 73
This version created on 05 October 2006

The Onset of Planet Formation in Brown Dwarf Disks


Daniel Apai, Univ. of Arizona, Tucson
Ilaria Pascucci, Univ. of Arizona, Tucson
Jeroen Bouwman, Max Planck Institute for Astronomy, Heidelberg
Antonella Natta, Arcetri Observatory, Florence
Thomas Henning, Max Planck Institute for Astronomy, Heidelberg
Cornelis Dullemond, Max Planck Institute for Astronomy, Heidelberg

Brown dwarf disks serve as an excellent laboratory for studying the
evolution of protoplanetary disks in an environment widely different
from that of young stars.  This difference in the parameters enables
us to disentangle the otherwise degenerate effects of stellar
luminosity, disk mass, and temperature distribution.  Here we present
results from an ongoing Spitzer/IRS survey of young brown dwarf disks
in the Cha I and rho Oph star-forming regions.  The high quality
mid-infrared spectroscopy enables the detection of spectral features
from silicates, both amorphous and crystalline.  Quantitive analysis
of the spectra demonstrates that grain growth and crystallization,
along with dust settling is ubiquitus in brown dwarf disks, similarly
to disks around young stars.  These processes are the first steps
toward planet formation, suggesting the robustness of this process.

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