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arXiv · astro-ph/0301063

The field brown dwarf LP 944-20 and the Castor moving group

I. Ribas
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Abstract

A reliable age estimation for the field brown dwarf LP 944-20 is accomplished through the analysis of its kinematic properties. The space velocities of this star strongly suggest its membership in the so-called Castor moving group. LP 944-20 can be sensibly assumed to have the group's age, which is estimated to be ~320 Myr, and metal content, which is found to be roughly solar. With these new constrains and the available photometry and lithium abundance, current brown dwarf models are put to a test. Using the IR magnitudes and the lithium diagnostics, the models are able to provide a reasonable description of the brown dwarf's properties (to within a few sigma) but yield an age which is roughly 50% larger than our estimate. Possible reasons for this discrepancy are discussed.

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I. Ribas. 2003-01-06. The field brown dwarf LP 944-20 and the Castor moving group. https://doi.org/10.1051/0004-6361%3A20030006

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