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Setting Limits on Supersymmetry Using Simplified Models
Published on: November 15, 2013
无的矮星系和来自超新星驱动的外流的暗物质核心
F Governato1, C Brook, L Mayer
1Astronomy Department, University of Washington, Seattle, Washington 98195, USA.
Nature
|January 16, 2010
概括
新的模拟表明,超新星驱动的外流可以解决矮星系形成中的冷暗物质 (CDM) 问题. 这解决了CDM理论与观测到的矮星系属性之间的差异.
科学领域:
- 天体物理学 天体物理学
- 宇宙学的宇宙学是什么?
- 银河系的形成 星系的形成
背景情况:
- 标准的冷暗物质 (CDM) 模型很难解释矮星系所观察到的特性.
- 矮星系通常表现出旋转的恒星盘,巨大的暗物质光环和恒定密度的核心,与CDM预测的密集膨胀和的中央暗物质形状形成鲜明对比.
- 现有的模型未能将理论预测与当今矮星系的观测数据相协调,这对CDM模型构成了重大挑战.
研究的目的:
- 调查在水力动力学模拟中解决不均的星际介质是否可以使矮星系属性与CDM模型相协调.
- 为了确定模拟中的特定物理过程是否可以自然产生矮星系的观测特征.
主要方法:
- 在一个包括CDM和宇宙常数的框架内进行了水力动力学模拟.
- 专注于解决不均的星际介质,以准确地建模气体动态.
- 分析了超新星驱动的外流对模拟星系中气体和暗物质分布的影响.
主要成果:
- 模拟表明,超新星的强烈外流有效地去除低角度动量的气体.
- 这一过程抑制了密集的恒星凸起的形成.
- 重要的是,这些外流将中心暗物质密度在中心千分之一秒内减少一半以上.
结论:
- 模拟自然产生矮星系类似物,它们没有凸起,并具有浅的中央暗物质形状.
- 这解决了矮星系对CDM模型构成的长期挑战.
- 这些发现表明,当复杂的重子物理学被准确地纳入时,CDM模型仍然可用于解释星系形成,包括矮星系.
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