Li T, Deng L, Zhao G
Beijing Astronomical Observatory, Chinese Academy of Sciences, National Astronomical Observatories, Geophysical Department, Peking University, Beijing.
Guang Pu Xue Yu Guang Pu Fen Xi. 2000 Aug;20(4):468-70.
The Calcium II triplet (Ca II T) lines in the near infrared spectral region is very important feature for late type stars, which serves as an important metallicity indicator for such stars. This is also true for stellar systems composed mainly of late type stars, such as old stellar clusters and galaxies. In this work, we made observations of the very famous spiral galaxy M31 and its dwarf elliptical companion M32, using the OMR spectrograph attached to the 2.16-meter telescope in Beijing Astronomical Observatory. Near-infrared spectra of the nuclear and disk regions on M31, as well as two slices along the major and the minor axis of M32, are derived. Equivalent widths of the Ca II triplet lines are measured using normal astrophysical spectrum analyzing techniques. The results are fundamental data for these two galaxies, which can be applied to researches for stellar population analysis of these galaxies.
近红外光谱区域的钙 II 三线态（Ca II T）谱线是晚型恒星的一个非常重要的特征，它是这类恒星重要的金属丰度指标。对于主要由晚型恒星组成的恒星系统，如古老的恒星团和星系，情况也是如此。在这项工作中，我们使用北京天文台 2.16 米望远镜上的 OMR 光谱仪对非常著名的旋涡星系 M31 及其矮椭圆伴星系 M32 进行了观测。获得了 M31 核区和盘区的近红外光谱，以及沿 M32 长轴和短轴的两条切片光谱。利用常规天体物理光谱分析技术测量了 Ca II 三线态谱线的等效宽度。这些结果是这两个星系的基础数据，可应用于对这些星系的恒星群体分析研究。
