H- and K-band methane features in an L dwarf, 2MASS 0920+35

被引：17

作者：

Nakajima, T

Tsuji, T

Yanagisawa, K

机构：

[1] Natl Astron Observ, Mitaka, Tokyo 1818588, Japan

[2] Univ Tokyo, Inst Astron, Mitaka, Tokyo 1810015, Japan

[3] Okayama Astrophys Observ, Okayama 7190232, Japan

来源：

ASTROPHYSICAL JOURNAL | 2001年 / 561卷 / 01期

关键词：

stars : late-type; stars; low-mass; brown dwarfs;

D O I：

10.1086/324440

中图分类号：

P1 [天文学];

学科分类号：

0704 ;

摘要：

We have obtained near-infrared spectra of three L dwarfs discovered by the Two Micron All Sky Survey, 1506+13 (L3), 1507-16 (L5), and 0920+35 (L6.5). From the comparison of the H- and K-band spectra of these L dwarfs, we have found the presence of methane absorption in 0920+35. This implies that detectable methane absorption in the H and K bands, usually considered the signature of a T dwarf, can be present in objects classified optically as late L. Methane detection in L dwarfs is consistent with the presence of a dust layer deep in the atmosphere, as the unified model of Tsuji suggests.

引用

页码：L119 / L122

页数：4

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