An L0 dwarf companion in the brown dwarf desert, at 30 AU

T. Forveille; D. Ségransan; P. Delorme; E. L. Martín; X. Delfosse; J. A. Acosta-Pulido; J. -L. Beuzit; A. Manchado; M. Mayor; C. Perrier; S. Udry

doi:10.1051/0004-6361:200400069

arXiv · astro-ph/0409112

An L0 dwarf companion in the brown dwarf desert, at 30 AU

T. Forveille·D. Ségransan·P. Delorme·E. L. Martín·X. Delfosse·J. A. Acosta-Pulido·J. -L. Beuzit·A. Manchado·M. Mayor·C. Perrier·S. Udry

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Abstract

We present the discovery of an L0 companion to the nearby M1.5 dwarf G 239-25, at a projected distance of 31 AU. It is the faintest companion discovered so far in our adaptive optics survey of all known M dwarfs within 12 pc, and it lies at the stellar/substellar limit. Given the assumed age of the primary star, the companion is likely an extremely low mass star. The long orbital period of G 239-25 AB ($\approx 100$ years) precludes a direct mass determination, but the relatively wide angular separation will allow detailed analyses of its near infrared and visible spectra.

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T. Forveille, D. Ségransan, P. Delorme, E. L. Martín, X. Delfosse, J. A. Acosta-Pulido, J. -L. Beuzit, A. Manchado, M. Mayor, C. Perrier, S. Udry. 2004-09-06. An L0 dwarf companion in the brown dwarf desert, at 30 AU. https://doi.org/10.1051/0004-6361%3A200400069

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