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arXiv · 1009.4650

A brown dwarf companion to the intermediate-mass star HR6037

N. Huelamo·D. E. A. Nuernberger·V. D. Ivanov·G. Chauvin·G. Carraro·M. F. Sterzik·C. H. F. Melo·M. Bonnefoy·M. Hartung·X. Haubois·C. Foellmi
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Abstract

In the course of an imaging survey we have detected a visual companion to the intermediate-mass star HR 6037. In this letter, we present two epoch observations of the binary with NACO/VLT, and near-IR spectroscopy of the secondary with ISAAC/VLT. The NACO observations allow us to confirm HR 6037B as a co-moving companion. Its J and H band ISAAC spectra suggest the object has an spectral type of M9+-1, with a surface gravity intermediate between that of 10 Myr dwarfs and field dwarfs with identical spectral type. The comparison of its Ks-band photometry with evolutionary tracks allows us to derive a mass, effective temperature, and surface gravity of 62+-20 MJup, Teff = 2330+-200 K, and log g = 5.1+-0.2, respectively. The small mass ratio of the binary, -0.03, and its long orbital period, -5000 yr, makes HR 6037 a rare and uncommon binary system.

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N. Huelamo, D. E. A. Nuernberger, V. D. Ivanov, G. Chauvin, G. Carraro, M. F. Sterzik, C. H. F. Melo, M. Bonnefoy, M. Hartung, X. Haubois, C. Foellmi. 2010-09-23. A brown dwarf companion to the intermediate-mass star HR6037. https://doi.org/10.1051/0004-6361/201015708

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