AI 中文总结
研究球状星团中本征铁丰度分布，用基于Python的Q2工具确定13个银河系球状星团中92颗同类恒星的微分恒星参数和铁丰度，经蒙特卡罗模拟评估，多数球状星团无显著铁差异，仅少数有，数据不支持球状星团中铁广泛变化。
AI 中文摘要
球状星团包含多个恒星族群，可能由富集星团内介质并产生次巨星的FG恒星子集组成，每个族群具有独特化学模式。传统上认为铁峰等重元素在多数球状星团中不受影响，但近期研究发现这些元素有显著内部差异。本研究旨在推导大量球状星团中精确且均匀的微分铁丰度，用基于Python的工具Q2确定13个银河系球状星团中92颗同类恒星的微分恒星参数和铁丰度，减少非局部热动平衡效应等影响。通过蒙特卡罗模拟评估测量差异的统计显著性，多数球状星团无显著铁差异，仅NGC1851、NGC3201和NGC5634有，特别是NGC3201的FG族群有明显差异。最后通过统计测试得出数据不支持球状星团中铁广泛变化的结论。
英文摘要
Globular Clusters (GCs) host multiple stellar populations, likely composed of a subset of FG stars that enriched the intracluster medium and gave rise to SG stars, each characterised by distinctive chemical patterns. These patterns typically include enhancements in elements such as N, Na, and Al, coupled with depletions in C, O, and Mg in SG stars. Traditionally, heavier elements such as those in the Fe-peak were considered unaffected in most GCs. However, recent studies have reported significant internal spreads in these elements, suggesting a more complex picture of chemical enrichment within GCs. This study seeks to derive precise and homogeneous differential iron abundances in a large sample of GCs. By doing so, our aim is to investigate the presence of intrinsic iron spreads within them and to assess the existence of differences in Fe between their stellar populations. We used the Python-based tool Q2 to determine both differential stellar parameters and iron abundances for 92 sibling stars, defined by the similarities in their stellar parameters, across 13 Galactic GCs. This differential approach reduces the influence of non-LTE effects, and minimises observational errors, and systematic biases linked to stellar parameters. We performed Monte Carlo simulations to evaluate the statistical significance of the measured spreads. Most of the GCs in our sample do not show evidence of statistically significant Fe spreads. Only a few exceptions emerge, namely NGC1851, NGC3201, and NGC5634, which display a highly significant iron spread. In particular, NGC3201 shows a particularly pronounced spread in its FG population, reflecting a potential inhomogeneous iron abundance in its pristine material. Finally, through statistical tests, we conclude that our data do not support the presence of a widespread iron variation in GCs.
Comments12 pages, 9 figures, and 3 tables. Table 1 only on CDS
