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arXiv · 1012.1319

A possible dividing line between massive planets and brown-dwarf companions

Johannes Sahlmann·Damien Segransan·Didier Queloz·Stephane Udry
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Abstract

Brown dwarfs are intermediate objects between planets and stars. The lower end of the brown-dwarf mass range overlaps with the one of massive planets and therefore the distinction between planets and brown-dwarf companions may require to trace the individual formation process. We present results on new potential brown-dwarf companions of Sun-like stars, which were discovered using CORALIE radial-velocity measurements. By combining the spectroscopic orbits and Hipparcos astrometric measurements, we have determined the orbit inclinations and therefore the companion masses for many of these systems. This has revealed a mass range between 25 and 45 Jupiter masses almost void of objects, suggesting a possible dividing line between massive planets and sub-stellar companions.

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Johannes Sahlmann, Damien Segransan, Didier Queloz, Stephane Udry. 2010-12-06. A possible dividing line between massive planets and brown-dwarf companions. https://doi.org/10.1017/s1743921311020047

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