Abstract
We present detailed modeling of the disk around the TW Hydrae Association (TWA) brown dwarf 2MASSW J1207334 - 393254 (2M1207), using Spitzer observations from 3.6 to 24 mu m. The spectral energy distribution (SED) does not show a high amount of flaring. We have obtained a good fit using a flat disk of mass between 10(-4) and 10(-6) M-circle dot, M less than or similar to 10(-11) M-circle dot yr(-1), and a large inclination angle between 60 degrees and 70 degrees. We have used three different grain models to fit the 10 mu m Si emission feature, and have found the results to be consistent with ISM-like dust. In comparison with other TWA members, this suggests lesser dust processing for 2M1207, which could be explained by mechanisms such as aggregate fragmentation and/or turbulent mixing. We have found a good fit using an inner disk radius equal to the dust sublimation radius, which indicates the absence of an inner hole in the disk. This suggests the presence of a small K - L' excess, similar to the observed K - [3.6] excess.
Original language | English |
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Pages (from-to) | 354-360 |
Number of pages | 7 |
Journal | The Astrophysical Journal |
Volume | 661 |
Issue number | 1 |
DOIs | |
Publication status | Published - 20 May 2007 |
Keywords
- accretion, accretion disks
- circumstellar matter
- infrared : stars
- stars : individual (2MASSW J1207334-393254)
- stars : low-mass
- brown dwarfs
- PLANETARY-MASS COMPANION
- GRAIN-GROWTH
- SPITZER OBSERVATIONS
- CIRCUMSTELLAR DISKS
- YOUNG
- STARS
- ACCRETION
- DUST
- SEQUENCE
- OBJECTS