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Exploring Brown Dwarf Disks

A. Natta·L. Testi
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Abstract

We discuss the spectral energy distribution of three very low mass objects in Chamaeleon I for which ground-based spectroscopy and photometry as well as ISO measurements in the mid-infrared are available (Comeron et al. 2000; Persi et al. 2000). One of these stars (Cha Halpha1) is a bona-fide brown dwarf, with mass 0.04-0.05 Msun. We show that the observed emission is very well described by models of circumstellar disks identical to those associated to T Tauri stars, scaled down to keep the ratio of the disk-to-star mass constant and to the appropriate stellar parameters. This result provides a first indication that the formation mechanism of T Tauri stars (via core contraction and formation of an accretion disk) extends to objects in the brown dwarf mass range.

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A. Natta, L. Testi. 2001-07-26. Exploring Brown Dwarf Disks. https://doi.org/10.1051/0004-6361%3A20011055

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