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Title: The disk around the brown dwarf KPNO Tau 3

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{sup –4} M{sub ☉} (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 <2.1 × 10{sup –4} M{sub ☉} and <2.7 × 10{sup –4} M{sub ☉}, 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 asmore » low-mass stars.« less

Authors:
; ;  [1];  [2];  [3];  [4];  [5]
  1. Department of Physics and Astronomy, University of Victoria, Victoria, BC V8W 3P6 (Canada)
  2. Department of Astronomy, University of California at Berkeley, Hearst Field Annex, B-20, Berkeley, CA 94720-3411 (United States)
  3. School of Physics and Astronomy, University of St Andrews, North Haugh, St Andrews, KY16 9SS (United Kingdom)
  4. Joint Astronomy Centre, 660 North Aóhoku Place, University Park, Hilo, HI 96720 (United States)
  5. Department of Astronomy and Astrophysics, University of Toronto, 50 St. George Street, Toronto, ON M5S 3H4 (Canada)
Publication Date:
OSTI Identifier:
22365644
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal; Journal Volume: 789; Journal Issue: 2; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; ACCRETION DISKS; BOLOMETERS; DETECTION; DISTRIBUTION; DUSTS; DWARF STARS; ENERGY SPECTRA; GRAIN SIZE; MASS; PROTOPLANETS; SIMULATION; T TAURI STARS; TELESCOPES

Citation Formats

Broekhoven-Fiene, Hannah, Matthews, Brenda, Di Francesco, James, Duchêne, Gaspard, Scholz, Aleks, Chrysostomou, Antonio, and Jayawardhana, Ray. The disk around the brown dwarf KPNO Tau 3. United States: N. p., 2014. Web. doi:10.1088/0004-637X/789/2/155.
Broekhoven-Fiene, Hannah, Matthews, Brenda, Di Francesco, James, Duchêne, Gaspard, Scholz, Aleks, Chrysostomou, Antonio, & Jayawardhana, Ray. The disk around the brown dwarf KPNO Tau 3. United States. doi:10.1088/0004-637X/789/2/155.
Broekhoven-Fiene, Hannah, Matthews, Brenda, Di Francesco, James, Duchêne, Gaspard, Scholz, Aleks, Chrysostomou, Antonio, and Jayawardhana, Ray. Thu . "The disk around the brown dwarf KPNO Tau 3". United States. doi:10.1088/0004-637X/789/2/155.
@article{osti_22365644,
title = {The disk around the brown dwarf KPNO Tau 3},
author = {Broekhoven-Fiene, Hannah and Matthews, Brenda and Di Francesco, James and Duchêne, Gaspard and Scholz, Aleks and Chrysostomou, Antonio and Jayawardhana, Ray},
abstractNote = {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{sup –4} M{sub ☉} (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 <2.1 × 10{sup –4} M{sub ☉} and <2.7 × 10{sup –4} M{sub ☉}, 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.},
doi = {10.1088/0004-637X/789/2/155},
journal = {Astrophysical Journal},
number = 2,
volume = 789,
place = {United States},
year = {Thu Jul 10 00:00:00 EDT 2014},
month = {Thu Jul 10 00:00:00 EDT 2014}
}
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