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.
@article{arxiv.1007.2406,
title = {A Methane Imaging Survey for T Dwarf Candidates in Rho Ophiuchi},
author = {K. E. Haisch and M. Barsony and C. Tinney},
journal= {arXiv preprint arXiv:1007.2406},
year = {2015}
}