光谱分类;旧的和当代的
Spectral Classification; Old and Contemporary
摘要：
从光谱分类的历史帐户开始，通过额外的标准进行细化。描述了用于每个光谱类的二维分类的线强度和比率。提出了一个贫金属星的平行分类方案和分类标准。光谱分类的扩展M以外的L和T和光谱分类标准，这些类进行了说明。介绍了基于不同自动化方法的当代分类方法。
英文摘要：
Beginning with a historical account of the spectral classification, its refinement through additional criteria is presented. The line strengths and ratios used in two dimensional classifications of each spectral class are described. A parallel classification scheme for metal-poor stars and the standards used for classification are presented. The extension of spectral classification beyond M to L and T and spectroscopic classification criteria relevant to these classes are described. Contemporary methods of classifications based upon different automated approaches are introduced.
机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。
