An extremely metal-deficient globular cluster in the Andromeda Galaxy

doi:10.1126/science.abb1970

GSTDTAP > 气候变化

DOI	10.1126/science.abb1970
	An extremely metal-deficient globular cluster in the Andromeda Galaxy
	Søren S. Larsen; Aaron J. Romanowsky; Jean P. Brodie; Asher Wasserman
	2020-11-20
发表期刊	Science
出版年	2020
英文摘要	Globular clusters (GCs) are gravitationally bound assemblies of thousands to millions of stars that orbit in the outskirts of large galaxies. GCs consist of old stars with low metallicity containing low proportions of chemical elements heavier than hydrogen and helium. However, GCs appear to have a minimum metallicity, known as the floor, implying that at least some of those elements were required for their formation. Larsen et al. have found a GC in the nearby Andromeda Galaxy with a metallicity beneath the floor. This unexpected discovery will inform models of GC formation and incorporation into galaxies. Science , this issue p. [970][1] Globular clusters (GCs) are dense, gravitationally bound systems of thousands to millions of stars. They are preferentially associated with the oldest components of galaxies, so measurements of their composition can constrain the build-up of chemical elements in galaxies during the early Universe. We report a massive GC in the Andromeda Galaxy (M31), RBC EXT8, that is extremely depleted in heavy elements. Its iron abundance is about 1/800 that of the Sun and about one-third that of the most iron-poor GCs previously known. It is also strongly depleted in magnesium. These measurements challenge the notion of a metallicity floor for GCs and theoretical expectations that massive GCs could not have formed at such low metallicities. [1]: /lookup/doi/10.1126/science.abb1970
领域	气候变化 ; 资源环境
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文献类型	期刊论文
条目标识符	http://119.78.100.173/C666/handle/2XK7JSWQ/304405
专题	气候变化资源环境科学
推荐引用方式 GB/T 7714	Søren S. Larsen,Aaron J. Romanowsky,Jean P. Brodie,et al. An extremely metal-deficient globular cluster in the Andromeda Galaxy[J]. Science,2020.
APA	Søren S. Larsen,Aaron J. Romanowsky,Jean P. Brodie,&Asher Wasserman.(2020).An extremely metal-deficient globular cluster in the Andromeda Galaxy.Science.
MLA	Søren S. Larsen,et al."An extremely metal-deficient globular cluster in the Andromeda Galaxy".Science (2020).