在原始原星周围的磁盘的形成和碎片化
Paul C Clark1, Simon C O Glover, Rowan J Smith
1Institut für Theoretische Astrophysik, Zentrum für Astronomie der Universität Heidelberg, Albert-Ueberle-Str. 2, 69120 Heidelberg, Germany. pcc@ita.uni-heidelberg.de
概括
宇宙的第一个恒星通常是密切的多个系统的一部分,而不是以前认为的孤独. 它们的磁盘的引力碎片可能形成了这些早期的双星和更高阶恒星系统.
科学领域:
- 天文学和天体物理学
- 宇宙学的宇宙学是什么?
- 恒星进化 恒星进化
背景情况:
- 首颗恒星的形成标志着宇宙黑暗时代的结束.
- 之前的模型表明,这些巨大的恒星单独形成或在暗物质迷你星中形成广泛的双星.
- 早期恒星形成的性质显著影响了宇宙的后续演变.
研究的目的:
- 为了研究宇宙中形成的第一个恒星的多重性.
- 挑战目前普遍认为的单独的第一颗恒星形成的概念.
- 了解控制早期恒星系统形成的机制.
主要方法:
- 暗物质迷你星体中早期恒星形成的数值模拟.
- 对原恒星盘中的引力碎片化过程的分析.
- 模拟二进制和更高阶系统的形成.
主要成果:
- 模拟表明,第一个恒星经常是在紧密的多重系统中形成的.
- 这些早期恒星周围的原星盘是引力不稳定的.
- 这种不稳定导致了碎片化,产生密集的二进制和更高阶系统.
结论:
- 最初的恒星通常是多个恒星系统的成员,这与之前的假设相反.
- 积累盘的重力分裂是形成这些早期多重系统的关键机制.
- 这些发现重塑了我们对早期宇宙结构形成和演变的理解.
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