论文标题
来自隆起球体的58个金属贫困星的高等光谱分析的丰度分析
Abundance analysis of APOGEE spectra for 58 metal-poor stars from the bulge spheroid
论文作者
论文摘要
银河系的中心部分容纳了许多恒星种群，包括球形凸起的恒星，恒星通过棒，内晕，内部厚磁盘，内部薄磁盘以及过去积聚事件的碎屑移动到凸起。我们确定了属于球体凸起的恒星种群的58个候选恒星的样本，并分析了它们的丰度。 Mg，Ca和Si系的本计算与Apogee-AppCap丰度一致，而C，N，O和CE的丰度被重新检查。我们发现氧气中的正常$α$ - 元素增强功能类似于镁，Si和Ca丰度，这是Baade窗口中光学中调查的其他凸起恒星的典型代表。这些恒星中[O/Fe]的增强表明它们不属于积聚的碎片。没有发现n个丰度的传播，并且没有一个样品恒星富含N，表明这些恒星不是第二代恒星起源于球形簇。相反
The central part of the Galaxy host a multitude of stellar populations, including the spheroidal bulge stars, stars moved to the bulge through secular evolution of the bar, inner halo, inner thick disk, inner thin disk, as well as debris from past accretion events. We identified a sample of 58 candidate stars belonging to the stellar population of the spheroidal bulge, and analyse their abundances. The present calculations of Mg, Ca, and Si lines are in agreement with the APOGEE-ASPCAP abundances, whereas abundances of C, N, O, and Ce are re-examined. We find normal $α$-element enhancements in oxygen, similar to magnesium, Si, and Ca abundances, which are typical of other bulge stars surveyed in the optical in Baade's Window. The enhancement of [O/Fe] in these stars suggests that they do not belong to accreted debris. No spread in N abundances is found, and none of the sample stars is N-rich, indicating that these stars are not second generation stars originated in globular clusters. Ce instead is enhanced in the sample stars, which points to an s-process origin such as due to enrichment from early generations of massive fast rotating stars, the so-called spinstars
