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arXiv · astro-ph/0409323

A Giant Planet Candidate near a Young Brown Dwarf

G. Chauvin·A. -M. Lagrange·C. Dumas·B. Zuckerman·D. Mouillet·I. Song·J. -L. Beuzit·P. Lowrance
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Abstract

We present deep VLT/NACO infrared imaging and spectroscopic observations of the brown dwarf 2MASSWJ1207334-393254, obtained during our on-going adaptive optics survey of southern young, nearby associations. This 25 MJup brown dwarf, located 70 pc from Earth, has been recently identified as a member of the TW Hydrae Association (age 8 Myr). Using adaptive optics infrared wavefront sensing to acquire sharp images of its circumstellar environment, we discovered a very faint and very red object at a close separation of 780 mas (55 AU). Photometry in the H, Ks and L' bands and upper limit in J-band are compatible with a spectral type L5-L9.5. Near-infrared spectroscopy is consistent with this spectral type estimate. Different evolutionary models predict an object within the planetary regime with a mass of 5+-2 MJup and an effective temperature of Teff=1250+-200K.

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G. Chauvin, A. -M. Lagrange, C. Dumas, B. Zuckerman, D. Mouillet, I. Song, J. -L. Beuzit, P. Lowrance. 2004-09-14. A Giant Planet Candidate near a Young Brown Dwarf. https://doi.org/10.1051/0004-6361%3A200400056

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