Five new very low mass binaries

G. Montagnier; D. Segransan; J. -L. Beuzit; T. Forveille; P. Delorme; X. Delfosse; C. Perrier; S. Udry; M. Mayor; G. Chauvin; A. -M. Lagrange; D. Mouillet; T. Fusco; P. Gigan; E. Stadler

doi:10.1051/0004-6361:20066120

arXiv · astro-ph/0609059

Five new very low mass binaries

G. Montagnier·D. Segransan·J. -L. Beuzit·T. Forveille·P. Delorme·X. Delfosse·C. Perrier·S. Udry·M. Mayor·G. Chauvin·A. -M. Lagrange·D. Mouillet·T. Fusco·P. Gigan·E. Stadler

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Abstract

We report the discovery of companions to 5 nearby late M dwarfs (>M5), LHS1901, LHS4009, LHS6167, LP869-26 and WT460, and we confirm that the recently discovered mid-T brown dwarf companion to SCR1845-6357 is physically bound to that star. These discoveries result from our adaptive optics survey of all M dwarfs within 12 pc. The new companions have spectral types M5 to L1, and orbital separations between 1 and 10 AU. They add significantly to the number of late M dwarfs binaries in the immediate solar neighbourhood, and will improve the multiplicity statistics of late M dwarfs. The expected periods range from 3 to 130 years. Several pairs thus have good potential for accurate mass determination in this poorly sampled mass range.

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G. Montagnier, D. Segransan, J. -L. Beuzit, T. Forveille, P. Delorme, X. Delfosse, C. Perrier, S. Udry, M. Mayor, G. Chauvin, A. -M. Lagrange, D. Mouillet, T. Fusco, P. Gigan, E. Stadler. 2006-09-04. Five new very low mass binaries. https://doi.org/10.1051/0004-6361%3A20066120

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