Bibcode
Riaz, Basmah; Lodieu, Nicolas; Gizis, John E.
Referencia bibliográfica
The Astrophysical Journal, Volume 705, Issue 2, pp. 1173-1182 (2009).
Fecha de publicación:
11
2009
Revista
Número de citas
24
Número de citas referidas
20
Descripción
We present Spitzer/IRAC and MIPS 24 μm observations for 28 brown
dwarfs in the Upper Scorpius (UppSco) region. We find a disk fraction of
10.7%+8.7% -3.3%. One object shows a small excess
at 24 μm but none at shorter wavelengths, and may be a candidate
transition disk. Three objects show emission in the 10 μm silicate
feature and we present compositional fits for these sources. Flat
structures are observed for all disk sources in UppSco. Also presented
are the MIPS/70 μm observations for the TW Hydrae Association brown
dwarf 2MASS J1139511-315921. We discuss the structure and chemistry of
brown dwarf disks at ages of ~5-10 Myr, and consider the possible
effects of the brown dwarf densities in these clusters on the disk
lifetimes.