Metallicities of RGB stars in dwarf galaxies

We present spectroscopic metallicities of individual stars in seven gas-rich dwarf irregular galaxies (dIrrs), and we show that dIrrs obey the same mass-metallicity relation as...本研究报道了7个富气体矮不规则星系（dwarf irregular galaxies，dIrrs）中单颗恒星的光谱金属丰度，并证实矮不规则星系遵循与……一致的质量-金属丰度关系。