An upper limit on the granularity of the local stellar halo

被引：22

作者：

Gould, A

机构：

[1] Ohio State Univ, Dept Astron, Columbus, OH 43210 USA

[2] Inst Adv Study, Princeton, NJ 08540 USA

来源：

ASTROPHYSICAL JOURNAL | 2003年 / 592卷 / 02期

基金：

美国国家科学基金会;

关键词：

galaxies : formation; Galaxy : structure; stars : kinematics; stars : statistics; subdwarfs; IMPROVED ASTROMETRY; LUYTEN CATALOG; TIDAL TAILS; GALAXY; STARS; SUBSTRUCTURE; PHOTOMETRY;

D O I：

10.1086/377525

中图分类号：

P1 [天文学];

学科分类号：

0704 ;

摘要：

I use the statistical properties of 4588 nearby halo stars to show that if the local stellar halo is composed of cold streams from disrupted dwarf satellites as is predicted by popular cosmologies, then at 95% confidence there are at least 400 such streams. Moreover, no stream can contain more than 5.0% of the local stars, while average streams must contain less than 0.25%.

引用

收藏

页码：L63 / L66

页数：4

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