Survey of Three Brown Dwarfs Finds Disk Around KPNO TAU 3

THE DISK AROUND THE BROWN DWARF KPNO TAU 3

Authors:

Broekhoven-Fiene et al

Abstract:

We present submillimeter observations of the young brown dwarfs KPNO Tau 1, KPNO Tau 3, and KPNO Tau 6 at 450 μm and 850 μm taken with the Submillimetre Common-User Bolometer Array on the James Clerk Maxwell Telescope. KPNO Tau 3 and KPNO Tau 6 have been previously identified as Class II objects hosting accretion disks, whereas KPNO Tau 1 has been identified as a Class III object and shows no evidence of circumsubstellar material. Our 3σ detection of cold dust around KPNO Tau 3 implies a total disk mass of (4.0 ± 1.1) × 10–4 M ☉ (assuming a gas to dust ratio of 100:1). We place tight constraints on any disks around KPNO Tau 1 or KPNO Tau 6 of less than 2.1 × 10–4 M ☉ and less than 2.7 × 10–4 M ☉, respectively. Modeling the spectral energy distribution of KPNO Tau 3 and its disk suggests the disk properties (geometry, dust mass, and grain size distribution) are consistent with observations of other brown dwarf disks and low-mass T-Tauri stars. In particular, the disk-to-host mass ratio for KPNO Tau 3 is congruent with the scenario that at least some brown dwarfs form via the same mechanism as low-mass stars.