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A companion to AB Pic at the planet/brown dwarf boundary

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

We report deep imaging observations of the young, nearby star AB Pic, a member of the large Tucana-Horologium as sociation. We have detected a faint, red source 5.5" South of the star with JHK colors compatible with that of a young substellar L dwarf. Follow-up observations at two additional epochs confirm, with a confidence level of 4.7sigma, that the faint red object is a companion to AB Pic rather than it being a stationary background object. A low resolution K-band spectrum indicates an early-L spectral type for the companion. Finally, evolutionary model predictions based on the JHK photometry of AB Pic b indicate a mass of 13 to 14 MJup if its age is ~30Myr. Is AB Pic b a massive planet or a minimum mass brown dwarf?

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G. Chauvin, A. -M. Lagrange, B. Zuckerman, C. Dumas, D. Mouillet, I. Song, J. -L. Beuzit, P. Lowrance, M. S. Bessell. 2005-04-29. A companion to AB Pic at the planet/brown dwarf boundary. https://doi.org/10.1051/0004-6361%3A200500111

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