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arXiv · 1007.2406

A Methane Imaging Survey for T Dwarf Candidates in Rho Ophiuchi

K. E. Haisch Jr.·M. Barsony·C. Tinney
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Abstract

We report the results of the first deep, wide-field, near-infrared methane imaging survey of the Rho Ophiuchi cloud core to search for T dwarfs. Among the 6587 objects detected, 22 were identified as T dwarf candidates. Brown dwarf models indicate that at the age and distance of the Rho Ophiuchi cloud, these T dwarf candidates have masses between 1 and 2 Jupiter masses. If confirmed as genuine T dwarfs, these objects would be the youngest, lowest mass, and lowest gravity free-floating objects ever directly observed. The existence of these candidates suggests that the initial mass function of the Rho Ophiuchi cloud extends well into the regime of planetary mass objects. A large fraction (59% +/- 16%) of our T dwarf candidates appear to be surrounded by circumstellar disks, and thus represent the lowest mass objects yet found to harbor circumstellar disks.

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K. E. Haisch Jr., M. Barsony, C. Tinney. 2010-07-14. A Methane Imaging Survey for T Dwarf Candidates in Rho Ophiuchi. https://doi.org/10.1088/2041-8205%2F719%2F1%2Fl90

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