漩涡星系M31和椭圆星系M32CaⅡ三重线的等值宽度

CaⅡ Triplet Equivalent Widths of Spiral Galaxy M31 and Elliptical Galaxy M32

利用北京天文台 2 1 6米望远镜的卡焦摄谱仪 ,我们观测了著名的漩涡星系M 3 1核区与盘区以及椭圆星系M3 2长轴方向与短轴方向的近红外光谱。对这些区域的重要光谱特征———CaⅡ三重线进行了测量 ,得到它们的等值宽度。

The Calcium Ⅱ triplet (CaⅡ 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 216 meter telescope in Beijing Astronomical Observatory.Nearinfrared 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 CaⅡ 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.