FeH Absorption in the Near-Infrared Spectra of Late M and L Dwarfs
FeH Absorption in the Near-Infrared Spectra of Late M and L Dwarfs
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晚期 M 和 L 矮星近红外光谱中的 FeH 吸收
DOI：
10.1086/344525
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发表时间：
2002
期刊：
影响因子：
--
通讯作者：
W. Vacca
中科院分区：
文献类型：
--
作者：
M. Cushing;J. Rayner;S. Davis;W. Vacca
我们提出了中等分辨率的Z-，J-和H-波段光谱的光谱类型范围从M8到L7.5的四个晚型矮星。为了确定它们的近红外光谱中许多弱吸收特征的来源，并受到最近在本影和冷星星光谱中1.6 μm附近FeH的E4-A4系统的初步鉴定的启发，我们将矮光谱与实验室FeH发射光谱进行了比较。我们已经确定了近100 FeH吸收功能的z-，J-和H-带光谱的矮星。特别是，我们已经确定了34个功能，占主导地位的外观的H-波段光谱的矮星，并出现在实验室FeH光谱。最后，在L7.5矮星的光谱中，所有这些特征都很弱或不存在，这与最新的L矮星光谱中已知的FeH带头的减弱是一致的。
We present medium-resolution z-, J-, and H-band spectra of four late-type dwarfs with spectral types ranging from M8 to L7.5. In an attempt to determine the origin of numerous weak absorption features throughout their near-infrared spectra, and motivated by the recent tentative identification of the E 4Π-A 4Π system of FeH near 1.6 μm in umbral and cool star spectra, we have compared the dwarf spectra to a laboratory FeH emission spectrum. We have identified nearly 100 FeH absorption features in the z-, J-, and H-band spectra of the dwarfs. In particular, we have identified 34 features that dominate the appearance of the H-band spectra of the dwarfs and that appear in the laboratory FeH spectrum. Finally, all of the features are either weaker or absent in the spectrum of the L7.5 dwarf, which is consistent with the weakening of the known FeH bandheads in the spectra of the latest L dwarfs.