发表机构
Lund University（隆德大学）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
通过测量714颗邻近F/G矮星和亚巨星的C、N、S、K、Cu丰度及修正后的O丰度，发现O、S、K、C等元素丰度比具有强年龄敏感性，能清晰区分银河薄盘和厚盘种群，扩展了化学演化诊断能力。
AI 中文摘要
[摘要] 我们旨在测定714颗邻近F和G矮星及亚巨星的碳、氮、硫、钾和铜丰度，并使用更新的非局部热力学平衡偏离修正重新推导氧丰度。这些元素扩展了我们先前研究的化学清单，并为银河薄盘和厚盘的相对增丰历史提供了新约束。氧的α元素行为得到确认，老年恒星相对于年轻恒星呈现增强序列。硫紧密跟随氧，而钾在[K/Fe]中表现出大致类似α的行为，但相对于氧存在残余趋势。碳和氮在[X/Fe]中仅显示适度分离，但在[X/O]中种群差异更明显。铜表现出强烈的金属丰度依赖性，并且与氧相比时，老年和年轻种群之间明显分离。我们还发现[O/Mg]不是常数，表明氧和镁提供了互补而非可互换的参考尺度。我们研究中分析的所有元素的定量比较表明，碳、氧、硫和钾是样本中对年龄最敏感的丰度比之一，并在老年和年轻盘种群之间提供了强区分。新的丰度测量显著扩展了该本地恒星样本的诊断能力。结果表明，相对于氧的丰度比，结合精确的恒星年龄，揭示了部分隐藏在传统[X/Fe]趋势中的种群差异。扩展的丰度清单为银河化学演化、银河考古学和大规模光谱巡天研究提供了同质的参考数据集。
英文摘要
[ABRIDGED] We aim to determine abundances of carbon, nitrogen, sulphur, potassium, and copper for 714 nearby F and G dwarf and subgiant stars, and to re-derive oxygen abundances using updated corrections for departures from the assumption of local thermodynamic equilibrium. These elements extend the chemical inventory of our previous studies and provide new constraints on the relative enrichment histories of the Galactic thin and thick disks. The alpha-element behaviour of oxygen is confirmed, with old stars defining an enhanced sequence relative to young stars. Sulphur closely follows oxygen, while potassium shows broadly alpha-like behaviour in [K/Fe] but residual trends relative to oxygen. Carbon and nitrogen show only modest separation in [X/Fe], but much clearer population differences in [X/O]. Copper displays a strong metallicity dependence and clear separation between old and young populations when compared to oxygen. We also find that [O/Mg] is not constant, demonstrating that oxygen and magnesium provide complementary rather than interchangeable reference scales. Quantitative comparisons of all elements analysed in our studies show that carbon, oxygen, sulphur, and potassium rank among the most age-sensitive abundance ratios in the sample and provide strong discrimination between old and young disk populations. The new abundance measurements substantially expand the diagnostic power of this local stellar sample. The results show that abundance ratios relative to oxygen, together with precise stellar ages, reveal population differences that are partly hidden in traditional [X/Fe] trends. The expanded abundance inventory provides a homogeneous reference dataset for studies of Galactic chemical evolution, Galactic archaeology, and large spectroscopic surveys.
CommentsAccepted for publication in A&A
