Galactic accretion and the outer structure of galaxies in the CDM model
Galactic accretion and the outer structure of galaxies in the CDM model
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CDM模型中的星系吸积和星系外部结构
DOI：
10.1093/mnras/stt1245
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发表时间：
2013-03
影响因子：
4.8
通讯作者：
White, Simon D. M.
中科院分区：
文献类型：
--
作者：
Boylan-Kolchin, Michael;Guo, Qi;Frenk, Carlos S.;White, Simon D. M.
我们将Guo et al.（2011）的半解析星系形成模型与库珀et al.（2010）的粒子标记技术相结合，预测了Millennium II Lambda-CDM N体模拟中约1900个大质量暗物质晕（10^12- 10^14 M_sol）代表性样本的星系表面亮度分布。在这里，我们提出了我们的方法和基本结果集中在星系的外部区域，包括恒星吸积合并。这些模拟涵盖了从类银河系星系的恒星晕到星系团和星系团的“cD信封”的尺度，并解决了潮汐流等低表面亮度的子结构。我们发现，暗物质晕中心星系周围吸积恒星质量的面密度可以很好地用Sersic轮廓描述，其径向尺度和振幅随晕质量（M_200）系统地变化。总的恒星质量表面密度分布在吸积恒星开始主导星系本身形成的恒星的半径处破裂。由于吸积星对星系总质量的贡献更大，这种破裂随着M_200的增加而消失;由于M_星星和M_200之间的关系分散，当同一星系在恒星质量的仓中平均时，这种破裂就不那么明显了。为了检验我们的模型，我们推导出平均恒星质量表面密度分布的大质量星系在z~0.08叠加SDSS图像。我们的模型与这些堆叠的配置文件和其他文献中的数据一致，并作出预测，可以更严格地测试未来的调查，扩展到更暗的等照度线的星系的外部结构的分析。我们的结论是，这是可能的外部结构的球状组成部分的星系在很大程度上是由碰撞合并在其分级组装
We have combined the semi-analytic galaxy formation model of Guo et al. (2011) with the particle-tagging technique of Cooper et al. (2010) to predict galaxy surface brightness profiles in a representative sample of ~1900 massive dark matter haloes (10^12--10^14 M_sol) from the Millennium II Lambda-CDM N-body simulation. Here we present our method and basic results focusing on the outer regions of galaxies, consisting of stars accreted in mergers. These simulations cover scales from the stellar haloes of Milky Way-like galaxies to the 'cD envelopes' of groups and clusters, and resolve low surface brightness substructure such as tidal streams. We find that the surface density of accreted stellar mass around the central galaxies of dark matter haloes is well described by a Sersic profile, the radial scale and amplitude of which vary systematically with halo mass (M_200). The total stellar mass surface density profile breaks at the radius where accreted stars start to dominate over stars formed in the galaxy itself. This break disappears with increasing M_200 because accreted stars contribute more of the total mass of galaxies, and is less distinct when the same galaxies are averaged in bins of stellar mass, because of scatter in the relation between M_star and M_200. To test our model we have derived average stellar mass surface density profiles for massive galaxies at z~0.08 by stacking SDSS images. Our model agrees well with these stacked profiles and with other data from the literature, and makes predictions that can be more rigorously tested by future surveys that extend the analysis of the outer structure of galaxies to fainter isophotes. We conclude that it is likely that the outer structure of the spheroidal components of galaxies is largely determined by collisionless merging during their hierarchical assembly
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影响因子：
4.9
作者：
Daddi, E;Renzini, A;Windhorst, RA
通讯作者：
Windhorst, RA
DOI：
10.1007/978-94-009-0229-9_40
发表时间：
1995-02
影响因子：
4.8
作者：
G. Kauffmann
通讯作者：
G. Kauffmann
DOI：
10.1111/j.1365-2966.2012.20975.x
发表时间：
2011-12
影响因子：
4.8
作者：
L. Sales;J. Navarro;T. Theuns;J. Schaye;S. White;C. Frenk;R. Crain;C. D. Vecchia
通讯作者：
L. Sales;J. Navarro;T. Theuns;J. Schaye;S. White;C. Frenk;R. Crain;C. D. Vecchia
DOI：
10.1111/j.1365-2966.2009.15057.x
发表时间：
2008-12
影响因子：
4.8
作者：
J. González;C. Lacey;C. Baugh;C. Frenk;A. Cosmology;Durham;Caltech
通讯作者：
J. González;C. Lacey;C. Baugh;C. Frenk;A. Cosmology;Durham;Caltech
影响因子：
4.8
作者：
G. Kauffmann
通讯作者：
G. Kauffmann