THE ACCRETION OF DARK MATTER SUBHALOS WITHIN THE COSMIC WEB: PRIMORDIAL ANISOTROPIC DISTRIBUTION AND ITS UNIVERSALITY
文献类型:期刊论文
作者 | Kang, Xi1; Wang, Peng1,2 |
刊名 | ASTROPHYSICAL JOURNAL |
出版日期 | 2015-11-01 |
卷号 | 813期号:1 |
关键词 | galaxies: halos cosmology: theory dark matter large-scale structure of universe methods: statistical |
英文摘要 | The distribution of galaxies displays anisotropy on different scales and it is often referred to as galaxy alignment. To understand the origin of galaxy alignments on small scales, one must investigate how galaxies were accreted in the early universe and quantify their primordial anisotropy at the time of accretion. In this paper we use N-body simulations to investigate the accretion of subhalos, focusing on their alignment with halo shape and the orientation of mass distribution on the large scale, defined using the Hessian matrix of the density field. The large/small (e1/e3) eigenvalues of the Hessian matrix define the fast/slow collapse direction of matter on the large scale. We find that: (1) the halo major axis is well aligned with the e3 (slow collapse) direction, and it is stronger for massive halos; (2) subhalos are predominantly accreted along the major axis of the host halo, and the alignment increases with the host halo mass. Most importantly, this alignment is universal; (3) accretion of subhalos with respect to the e3 direction is not universal. In massive halos, subhalos are accreted along the e3 (even more strongly than the alignment with the halo major axis), but in low-mass halos subhalos are accreted perpendicular to e3. The transitional mass is lower at high redshift. The last result well explains the puzzling correlation (both in recent observations and simulations) that massive galaxies/halos have their spin perpendicular to the filament, and the spin of low-mass galaxies/halos is slightly aligned with the filament, under the assumption that the orbital angular momentum of subhalos is converted to halo spin. |
WOS标题词 | Science & Technology ; Physical Sciences |
类目[WOS] | Astronomy & Astrophysics |
研究领域[WOS] | Astronomy & Astrophysics |
关键词[WOS] | LARGE-SCALE STRUCTURE ; N-BODY SIMULATIONS ; SPIN ALIGNMENT ; SATELLITE GALAXIES ; GRAVITATIONAL-INSTABILITY ; ANGULAR-MOMENTUM ; MILKY-WAY ; FILAMENTS ; HALOS ; CLUSTERS |
收录类别 | SCI |
语种 | 英语 |
WOS记录号 | WOS:000365284100006 |
源URL | [http://libir.pmo.ac.cn/handle/332002/16043] |
专题 | 紫金山天文台_南极天文中心 |
作者单位 | 1.Partner Grp MPI Astron, Purple Mt Observ, Nanjing 210008, Jiangsu, Peoples R China 2.Univ Chinese Acad Sci, Grad Sch, Beijing 100049, Peoples R China |
推荐引用方式 GB/T 7714 | Kang, Xi,Wang, Peng. THE ACCRETION OF DARK MATTER SUBHALOS WITHIN THE COSMIC WEB: PRIMORDIAL ANISOTROPIC DISTRIBUTION AND ITS UNIVERSALITY[J]. ASTROPHYSICAL JOURNAL,2015,813(1). |
APA | Kang, Xi,&Wang, Peng.(2015).THE ACCRETION OF DARK MATTER SUBHALOS WITHIN THE COSMIC WEB: PRIMORDIAL ANISOTROPIC DISTRIBUTION AND ITS UNIVERSALITY.ASTROPHYSICAL JOURNAL,813(1). |
MLA | Kang, Xi,et al."THE ACCRETION OF DARK MATTER SUBHALOS WITHIN THE COSMIC WEB: PRIMORDIAL ANISOTROPIC DISTRIBUTION AND ITS UNIVERSALITY".ASTROPHYSICAL JOURNAL 813.1(2015). |
入库方式: OAI收割
来源:紫金山天文台
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