Long-slit optical spectroscopy of powerful far-infrared galaxies - The nature of the nuclear energy source
Long-slit optical spectroscopy of powerful far-infrared galaxies - The nature of the nuclear energy source
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强大的远红外星系的长缝光谱 - 核能源的本质
DOI：
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发表时间：
1989
期刊：
影响因子：
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通讯作者：
G. Miley
中科院分区：
文献类型：
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作者：
L. Armus;T. Heckman;G. Miley
提供了 47 个强大的远红外星系样本的光学光谱数据，这些星系被选择用于红外光谱形状，以及其他 6 个红外亮星系。星系核中老年恒星群的恒星吸收线通常非常弱。在远离原子核的区域发现非常弱的 Mg I 吸收，这意味着可见光谱主要由年轻恒星而不是活动星系核主导。至少有一个（可能有五个）星系具有可检测到的 WR 发射特征，为年轻恒星群体提供了额外的证据。大约 20% 的星系具有很强的巴尔默吸收线，表明存在大量中龄恒星群。 H-α 发射线的等效宽度可以建模为由大量年轻恒星群和中龄恒星群混合产生的。 44 参考文献
Optical spectroscopic data are presented for a sample of 47 powerful far-IR galaxies chosen for IR spectral shape, and for six other IR-bright galaxies. The stellar absorption lines expected from a population of old stars are generally very weak in the nuclei of the galaxies. Very weak Mg I absorption is found in regions well off the nucleus, implying that the visible spectrum is dominated by young stars and not by an AGN. At least one, and probably five, of the galaxies have detectable WR emission features, providing additional evidence for a young stellar population. About 20 percent of the galaxies have strong Balmer absorption lines, indicating the presence of a substantial intermediate-age stellar population. The equivalent width of the H-alpha emission line can be modeled as arising from a mixture of a large young population and an intermediate-age population of stars. 44 refs.