Comparative Spectroscopic Study of Stars in Nearby Dwarf Galaxies and in the Halo of Our Galaxy

利用SUBARU望远镜的高色散光谱仪（HDS）对附近几个矮星系的红巨星进行了高分辨率的光谱观测。这些红巨星的丰度分析是用银河系中几颗研究得很好的缺金属晕星作为参考进行的。在UMa矮星系的几颗红巨星中发现了几个有趣的丰度模式，这些模式与在银河晕恒星中发现的不同。这些发现可以用于模拟矮星系的演化历史。对六分星矮星系中红巨星的观测已于2007年1月完成。对这些恒星的分析将在几年内完成。

High resolution spectroscopic observations of red giant stars belonging to several nearby dwarf galaxies were carried out using the high dispersion spectrograph (HDS) of the SUBARU telescope. Abundance analyses of these red giants were performed using several well studied metal deficient halo stars in our Gaxaly as references. Several interesting abundance patterns, which are different from those found in Galactic halo stars, were discovered in a few red giant stars belonging to the UMa dwarf galaxy. These findings can be used in modeling the evolution history of dwarf galaxies. Observations of red giant stars in the Sextans dwarf galaxy have completed in January, 2007. Analyses of these stars will be completed within a few years.