The Onset of Methane in L Dwarfs
نویسندگان
چکیده
We have detected weak absorption features produced by the strong ν3 methane band at 3.3 μm in two L dwarfs, 2MASSW J1507476-162738 and 2MASSI J0825196+211552, classified by Kirkpatrick et al. (2000) as spectral types L5 and L7.5 respectively. These absorptions occur in objects warmer than any in which methane previously has been detected, and mark the first appearance of methane in the ultracool star – to – brown dwarf spectral sequence. Subject headings: stars: low-mass, brown dwarfs — infrared: stars — radiative transfer
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تاریخ انتشار 2000