论文标题
来自集成光钙-II三重曲线光谱的外晕M31球形簇的金属度
Metallicities of Outer Halo M31 Globular Clusters from Integrated Light Calcium-II Triplet Spectroscopy
论文作者
论文摘要
本文基于钙-II三胞胎（CAT）线的中等分辨率，集成光（IL）光谱法，介绍了仙女座星系外晕的GC的[Fe/H]比。猫的强度是通过将voigt曲线拟合到线条并集成这些曲线的；还考虑了定义的带通的集成。 [Fe/H]比使用具有CAT线强度的经验校准确定，这是从先前以高分辨率研究的M31 GC样本中得出的。新GCS的[Fe/H]比率表明，外晕GC通常比典型的内部光晕GC更具金属贫困，尽管还有更多金属富含金属的GC，这些GC看起来似乎已经从矮人卫星中得到了积聚。这些GC的金属性还对产生此子结构的外光环和矮卫星中的子结构的性质施加了重要的约束。
This paper presents [Fe/H] ratios for GCs in the outer halo of the Andromeda Galaxy, M31, based on moderate-resolution, integrated light (IL) spectroscopy of the calcium-II triplet (CaT) lines. The CaT strengths are measured by fitting Voigt profiles to the lines and integrating those profiles; integrations of defined bandpasses are also considered. The [Fe/H] ratios are determined using an empirical calibration with CaT line strength, as derived from another sample of M31 GCs that were previously studied at high-resolution. The [Fe/H] ratios for the new GCs reveal that the outer halo GCs are indeed generally more metal-poor than typical inner halo GCs, though there are several more metal-rich GCs that look to have been accreted from dwarf satellites. The metallicities of these GCs also place important constraints on the nature of the substructure in the outer halo and the dwarf satellites that created this substructure.
