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SpS1-The evolution of brown dwarf infrared spectroscopic properties

Published online by Cambridge University Press:  21 October 2010

Isabelle Baraffe
Affiliation:
Centre de Recherche Astrophysique de Lyon, UMR 5574: CNRS, Université de de Lyon, École Normale Supérieure de Lyon, 46 allée dItalie, F-69364 Lyon Cedex 07, France email: [email protected]
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Brown dwarfs (hereafter BDs) are formed, like stars, by interstellar cloud collapse, but attaining masses of less then 0.075 M (Baraffe et al. 1998), i.e. too low core temperatures (< 3.5 × 106 K) to stabilize the nuclear burning of the hydrogen PP chain. Therefore, even the most massive BDs begin cooling after some 109 yrs. However, for masses above 0.06 M, core temperatures become hotter than the lithium burning temperature (2.4 x 106 K). All BDs above 0.013 M (13 MJup) reach core temperatures above the 1.0 x 106 K necessary to burn deuterium from about 107 yrs. The IAU has adopted the definition of the planetary regime as objects having masses below the deuterium burning conditions. But BDs are likely to form well below this limit into the planetary mass regime down to some 5 MJup. It is therefore convenient, in the absence of indices on their formation mechanisms, to call them planetary mass objects or planemos.

Type
Contributed Papers
Copyright
Copyright © International Astronomical Union 2010

References

Allard, F. et al. 2001, ApJ 556, 357CrossRefGoogle Scholar
Baraffe, I. et al. 1998, A&A 337, 403Google Scholar
Baraffe, I. et al. 2009, ApJ 702, L27CrossRefGoogle Scholar
Burningham, B. et al. 2008, MNRAS 391, 320CrossRefGoogle Scholar
Chabrier, G. & Baraffe, I. 2000, ARA&A 38, 337Google Scholar
Cushing, M. C. et al. 2006, ApJ 648, 614CrossRefGoogle Scholar
Delorme, P. et al. 2008, A&A 482, 961Google Scholar
Freytag, B. et al. 2009, A&A in preparationGoogle Scholar
Saumon, D. et al. 2006, ApJ 647, 552CrossRefGoogle Scholar