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Probing Dust around Brown Dwarfs: The naked LP 944-20 and the Disk of Cha Ha2

D. Apai·I. Pascucci·Th. Henning·M. F. Sterzik·R. Klein·D. Semenov·E. Guenther·B. Stecklum
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Abstract

We present the first mid-infrared (MIR) detection of a field brown dwarf (BD) and the first ground-based MIR measurements of a disk around a young BD candidate. We prove the absence of warm dust surrounding the field BD LP 944-20. In the case of the young BD candidate Cha Ha2, we find clear evidence for thermal dust emission from a disk. Surprisingly, the object does not exhibit any silicate feature as previously predicted. We show that the flat spectrum can be explained by an optically thick flat dust disk.

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D. Apai, I. Pascucci, Th. Henning, M. F. Sterzik, R. Klein, D. Semenov, E. Guenther, B. Stecklum. 2002-06-13. Probing Dust around Brown Dwarfs: The naked LP 944-20 and the Disk of Cha Ha2. https://doi.org/10.1086/342210

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