The earliest stars and their relics in the Milky Way
The earliest stars and their relics in the Milky Way
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银河系中最早的恒星及其遗迹
DOI：
10.1111/j.1365-2966.2009.16225.x
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发表时间：
2009-09
影响因子：
4.8
通讯作者：
White, S. D. M.
中科院分区：
文献类型：
--
作者：
Gao, L.;Theuns, Tom;Frenk, C. S.;Jenkins, A.;Helly, J. C.;Navarro, J.;Springel, V.;White, S. D. M.
我们已经实现了一个简单的模型来识别水瓶座项目银河暗物质晕形成的高分辨率模拟中第一颗恒星和星系的可能位置。像银河系这样的星系中的第一颗恒星在红移 z = 35 附近形成；当 z = 10 时，年轻星系包含多达 ∼3 x 10 4 个暗物质晕，能够通过分子氢冷却形成恒星。这些迷你晕强烈聚集，反馈可能严重限制了形成的第三星族恒星的实际数量。到今天，第一批恒星的残余物将集中到主晕的中心。如果第二代长寿恒星在第一代（第一代恒星遗迹）附近形成，我们预计将在距银河系中心 30 h -1 kpc 范围内找到其中一半，并在卫星中找到相当一部分，通过其异常金属丰度模式可以将它们挑出来。第一个晕，其中气体可以通过原子氢线辐射冷却，形成于 z = 25；当 z = 10 时，此类“第一星系”的数量已增加至 ∼300 个。反馈可能会减少第一个星系在经历重要的恒星形成时的数量，但不会减少由于近邻合并而存活至今的数量。在 z = 10 之前形成的所有“第一星系”中有一半在 z ∼ 3 之前与主晕合并，并且大多数损失了很大一部分质量。然而，今天应该仍然有超过 20 个残余物在银河系中心~30 h -1 kpc 内运行。这些卫星的圆周速度为每秒几公里或更高，与已知的银河系矮星相当。它们是寻找最早恒星形成时代遗迹的有希望的狩猎场。
We have implemented a simple model to identify the likely sites of the first stars and galaxies in the high-resolution simulations of the formation of galactic dark matter haloes of the Aquarius Project. The first star in a galaxy like the Milky Way formed around redshift z = 35; by z = 10, the young galaxy contained up to ∼3 x 10 4 dark matter haloes capable of forming stars by molecular hydrogen cooling. These minihaloes were strongly clustered, and feedback may have severely limited the actual number of Population III stars that formed. By the present day, the remnants of the first stars would be strongly concentrated to the centre of the main halo. If a second generation of long-lived stars formed near the first (the first star relics), we would expect to find half of them within 30 h -1 kpc of the Galactic Centre and a significant fraction in satellites where they may be singled out by their anomalous metallicity patterns. The first halo in which gas could cool by atomic hydrogen line radiation formed at z = 25; by z = 10, the number of such 'first galaxies' had increased to ∼300. Feedback might have decreased the number of first galaxies at the time when they undergo significant star formation, but not the number that survive to the present because near neighbours merge. Half of all the 'first galaxies' that formed before z = 10 merge with the main halo before z ∼ 3 and most lose a significant fraction of their mass. However, today there should still be more than 20 remnants orbiting within the central ∼30 h -1 kpc of the Milky Way. These satellites have circular velocities of a few kilometres per second or more, comparable to those of known Milky Way dwarfs. They are a promising hunting ground for the remnants of the earliest epoch of star formation.
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DOI：
10.1111/j.1365-2966.2007.11814.x
发表时间：
2006-10
影响因子：
4.8
作者：
Liang Gao;N. Yoshida;Tom Abel;C. Frenk;A. Jenkins;V. Springel
通讯作者：
Liang Gao;N. Yoshida;Tom Abel;C. Frenk;A. Jenkins;V. Springel
DOI：
10.1111/j.1745-3933.2009.00748.x
发表时间：
2009-09
影响因子：
--
作者：
T. Okamoto;Carlos S. Frenk Tsukuba;Durham
通讯作者：
T. Okamoto;Carlos S. Frenk Tsukuba;Durham
DOI：
10.1111/j.1365-2966.2005.09416.x
发表时间：
2005-04
影响因子：
4.8
作者：
D. Reed;R. Bower;C. Frenk;Liang Gao;A. Jenkins;T. White;ICC-Durham;MPA-Garching;Antwerp
通讯作者：
D. Reed;R. Bower;C. Frenk;Liang Gao;A. Jenkins;T. White;ICC-Durham;MPA-Garching;Antwerp
DOI：
10.1086/423444
发表时间：
2003-12
期刊：
The Astrophysical Journal
影响因子：
--
作者：
Liang Gao;A. Loeb;P. J. E. Peebles;S. White;A. Jenkins
通讯作者：
Liang Gao;A. Loeb;P. J. E. Peebles;S. White;A. Jenkins
DOI：
10.1111/j.1365-2966.2004.08360.x
发表时间：
2004-04
影响因子：
4.8
作者：
Liang Gao;S. White;A. Jenkins;F. Stoehr;V. Springel
通讯作者：
Liang Gao;S. White;A. Jenkins;F. Stoehr;V. Springel