Efficient spectrographs at large telescopes have made it possible to obtain high-resolution spectra of stars with high signal-to-noise ratio and advances in model atmosphere analyses have enabled estimates of high-precision differential abundances of the elements from these spectra, i.e. with errors in the range 0.01–0.03 dex for F, G, and K stars. Methods to determine such high-precision abundances together with precise values of effective temperatures and surface gravities from equivalent widths of spectral lines or by spectrum synthesis techniques are outlined, and effects on abundance determinations from using a 3D non-LTE analysis instead of a classical 1D LTE analysis are considered. The determination of high-precision stellar abundances of the elements has led to the discovery of unexpected phenomena and relations with important bearings on the astrophysics of galaxies, stars, and planets, i.e. (i) Existence of discrete stellar populations within each of the main Galactic components (disk, halo, and bulge) providing new constraints on models for the formation of the Milky Way. (ii) Differences in the relation between abundances and elemental condensation temperature for the Sun and solar twins suggesting dust-cleansing effects in proto-planetary disks and/or engulfment of planets by stars; (iii) Differences in chemical composition between binary star components and between members of open or globular clusters showing that star- and cluster-formation processes are more complicated than previously thought; (iv) Tight relations between some abundance ratios and age for solar-like stars providing new constraints on nucleosynthesis and Galactic chemical evolution models as well as the composition of terrestrial exoplanets. We conclude that if stellar abundances with precisions of 0.01–0.03 dex can be achieved in studies of more distant stars and stars on the giant and supergiant branches, many more interesting future applications, of great relevance to stellar and galaxy evolution, are probable. Hence, in planning abundance surveys, it is important to carefully balance the need for large samples of stars against the spectral resolution and signal-to-noise ratio needed to obtain high-precision abundances. Furthermore, it is an advantage to work differentially on stars with similar atmospheric parameters, because then a simple 1D LTE analysis of stellar spectra may be sufficient. However, when determining high-precision absolute abundances or differential abundance between stars having more widely different parameters, e.g. metal-poor stars compared to the Sun or giants to dwarfs, then 3D non-LTE effects must be taken into account.

大型望远镜的高效摄谱仪使得获得具有高信噪比的恒星高分辨率光谱成为可能，并且模型大气分析的进步使得能够从这些光谱中高精度地估计元素的差异丰度，即有误差F、G 和 K 星的 dex 范围为 0.01–0.03。概述了根据谱线等效宽度或通过频谱合成技术确定此类高精度丰度以及有效温度和表面重力精确值的方法，以及使用 3D 非 LTE 分析而不是经典 1D 分析对丰度确定的影响考虑 LTE 分析。高精度恒星元素丰度的测定导致发现了意想不到的现象以及与星系、恒星和行星天体物理学的重要关系的关系，即（i）每个主银河系中存在离散的恒星族群组件（盘、晕和核球）为银河系形成模型提供了新的约束。 (ii) 太阳和太阳双胞胎的丰度和元素凝结温度之间关系的差异表明原行星盘中的尘埃净化作用和/或恒星吞没行星的作用； ㈢ 双星组件之间以及疏散星团或球状星团成员之间化学成分的差异，表明恒星和星团的形成过程比以前认为的更为复杂； (iv) 类太阳恒星的一些丰度比和年龄之间的紧密关系为核合成和银河化学演化模型以及类地系外行星的组成提供了新的约束。 我们的结论是，如果在研究更遥远的恒星以及巨星和超巨星分支上的恒星时能够实现精度为 0.01-0.03 dex 的恒星丰度，那么未来可能会出现许多与恒星和星系演化密切相关的有趣应用。因此，在规划丰度调查时，仔细平衡对大量恒星样本的需求与获得高精度丰度所需的光谱分辨率和信噪比非常重要。此外，对具有相似大气参数的恒星进行差分工作是一个优势，因为这样对恒星光谱进行简单的一维 LTE 分析就足够了。然而，当确定具有更广泛不同参数的恒星之间的高精度绝对丰度或差异丰度时，例如，贫金属恒星与太阳相比，或巨星与矮星相比，则必须考虑3D非LTE效应。