Brown Dwarf Disks at Ages of 5-10 Myr

Abstract

We present Spitzer/IRAC and MIPS 24mu archival 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 24mu but none at shorter wavelengths, and may be a candidate transition disk. Three objects show emission in the 10mu 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/70mu 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.

Accepted in ApJ

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Cited by in corpus (19)

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• Astrometric and photometric initial mass functions from the UKIDSS Galactic Clusters Survey: I The Pleiades
• Multi-fibre optical spectroscopy of low-mass stars and brown dwarfs in Upper Sco
• New Young Stars and Brown Dwarfs in the Upper Scorpius Association
• Astrometric and photometric initial mass functions from the UKIDSS Galactic Clusters Survey: IV Upper Sco
• Disc Frequencies for Brown Dwarfs in the Upper Scorpius OB Association: Implications for Brown Dwarf Formation Theories
• A WISE Survey of Circumstellar disks in the Upper Scorpius Association
• X-shooter spectroscopy of young stars with disks. The TW Hydrae association as a probe of the final stages of disk accretion
• A Census of the Circumstellar Disk Populations in the Sco-Cen Complex
• A Thermal Infrared Imaging Study of Very Low-Mass, Wide Separation Brown Dwarf Companions to Upper Scorpius Stars: Constraining Circumstellar Environments
• Stellar-Mass-Dependent Disk Structure in Coeval Planet-Forming Disks
• Very Low-Mass Stars and Brown Dwarfs in Upper Scorpius using Gaia DR1: Mass Function, Disks and Kinematics
• Spectral energy distribution simulations of a possible ring structure around the young, red brown dwarf G196-3B
• Herschel/PACS view of disks around low-mass stars and brown dwarfs in the TW Hya association
• Spitzer Spectroscopy of the Circumprimary Disk in the Binary Brown Dwarf 2MASS J04414489+2301513
• Herschel PACS and SPIRE Observations of TWA brown dwarf discs
• New constraints on the presence of debris disks around G 196-3 B and VHS J125601.92-125723.9 b