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Dawn Peterson (Univ. of Virginia) Tom Megeath (Univ. of Toledo). Young Brown Dwarfs in OMC 2/3: SpeX 0.8-2.5 µm Observations. from Peterson et al. 2007: "New Young Brown Dwarfs in the Orion Molecular Cloud 2/3 Region".
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Dawn Peterson (Univ. of Virginia) Tom Megeath (Univ. of Toledo) Young Brown Dwarfs in OMC 2/3: SpeX 0.8-2.5 µm Observations from Peterson et al. 2007: "New Young Brown Dwarfs in the Orion Molecular Cloud 2/3 Region"
Source Selection: Young Brown Dwarf Candidates in Orion Molecular Cloud 2/3 • From JHK-band imaging, we selected SpeX candidates based on location in the color-mag diagram: • Below hydrogen burning limit • Av > 7 • 13 < K < 16 mag
SpeX Spectra: Grid of Standards • Obtained SpeX single-prism mode spectra of giants, dwarfs and young stars of types M4-M9 in Taurus and IC 348 for comparison • 0.8 - 2.5 µm • R ~ 250
SpeX Spectra: OMC 2/3 Brown Dwarf Candidate 29 • Reference spectra (blue and red lines) from young members in Taurus • Compared strengths of water and CO absorption bands • Best fit: M8.5 (red spectrum)
Results Color-color diagram of the OMC 2/3 brown dwarfs. • 14 NEW low mass stars (M4-M6) and BDs (M6.5-M9) in OMC 2/3 with SpeX • Spitzer IRAC data shows brown dwarfs with excesses: 70% of them have disks! (approx. the same as was found for stars)