Old Stellar Populations and Cosmology

星系中古老的恒星群将被研究和用作 宇宙探测器 工作福尔斯逻辑上分为两个方面： 古老恒星星族和积分光谱的研究 se和使用旧的恒星种群，特别是 椭圆（E）和球形（SO）星系，作为 宇宙局部哈勃膨胀的不规则性。 在 后者的工作，一个使用E星系的项目， 在600-700 km s-1的整体运动的证据 我们周围星系的大球体的宇宙重构， 6000 km s-1的半径将扩大。 的这种运动 星系可以提供一个强大的约束宇宙学 理论，需要以各种可能的方式进行测试和探索。 为此，全面分析了N体宇宙模型 作为一种手段来阐明哈勃流中潜在的陷阱 将进行这类研究。 完全新的和 对邻近SO星系运动的独立估计将 可以与Es的值进行比较。 在古老的恒星种群领域，将开展一个项目， 继续测定金属丰度和元素丰度 E星系和球状星团中的比率。 实证 G矮星和K巨星吸收线特征的刻度 恒星与温度、丰度和表面重力的关系， 完成 这些结果将与理论结果进行比较。 合成光谱，当一个令人满意的理解 恒星光谱的实现，将有一个合成的 星系的综合光谱 椭圆长缝光谱 还将分析星系的径向丰度梯度， 新的、高质量的、高分辨率的恒星光谱将被 用于探索球状体之间的微小成分差异 星团恒星

Old stellar populations in galaxies will be studied and used as cosmological probes. The work falls logically into two areas: the study of old stellar populations and integrated spectra per se and the use of old stellar populations, specifically elliptical (E) and spherical (SO) galaxies, as tracers of irregularities in the local Hubble expansion of the universe. In the latter work, a project using E galaxies that has given evidence of a bulk motion at 600-700 km s-1 with respect to the cosmic restframe of a large sphere of galaxies around us out to 6000 km s-1 in radius will be expanded. This motion of the galaxies could provide a powerful constraint on cosmological theories and needs to be tested and probed in every possible way. To this end, a comprehensive analysis of N-body universe models as a means to illuminate potential pitfalls in Hubble flow studies of this type will be carried out. Completely new and independent estimates of the motions of nearby SO galaxies will be obtained to compare with those of Es. In the area of old stellar populations, a project will be continued to determine the metallicities and element abundance ratios in E galaxies and globular clusters. An empirical calibration of absorption-line features in G dwarf and K giant stars versus temperature, abundance, and surface gravity will be completed. These results will be compared to theoretical synthetic spectra, and, when a satisfactory understanding of stellar spectra is achieved, there will be a synthesizing of integrated spectra of galaxies. Long-slit spectra of elliptical galaxies will also be analyzed for radial abundance gradients, and new, high-quality, high-resolution stellar spectra will be used to explore small composition differences among globular cluster stars.