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arXiv · 1103.5744

On the Distribution of Orbital Eccentricities for Very Low-Mass Binaries

Trent J. Dupuy·Michael C. Liu
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Abstract

We have compiled a sample of 16 orbits for very low-mass stellar (<0.1 Msun) and brown dwarf binaries, enabling the first comprehensive study of the eccentricity distribution for such objects. We find that very low-mass binaries span a broad range of eccentricities (0.03 0.6) binaries at orbital periods comparable to our sample. In contrast, the circumstellar disk fragmentation model of Stamatellos & Whitworth (2009) predicts only high-e binaries and thus is highly inconsistent with our sample. These discrepancies could be explained if multiple formation processes have produced the field population.

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Trent J. Dupuy, Michael C. Liu. 2011-03-29. On the Distribution of Orbital Eccentricities for Very Low-Mass Binaries. https://doi.org/10.1088/0004-637x%2F733%2F2%2F122

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