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在激光产生的冲击波中生成缩放的原银河系种子磁场
G Gregori1, A Ravasio, C D Murphy
1Department of Physics, University of Oxford, Parks Road, Oxford OX1 3PU, UK. g.gregori1@physics.ox.ac.uk
Nature
|January 28, 2012
概括
比尔曼电池过程在早期星系中产生种子磁场. 实验室实验表明,这些场可以被流放大,影响银河系在宇宙时间尺度上的演变.
科学领域:
- 天体物理学 天体物理学
- 等离子体物理学的物理学
背景情况:
- 银河系磁场对于银河系进化至关重要.
- 比尔曼电池过程是产生原始磁场的领先候选者.
研究的目的:
- 为了实验性地研究比尔曼电池效应.
- 为了确定实验室产生的种子磁场对天体物理环境的可扩展性.
主要方法:
- 使用高功率激光系统来模拟天体物理条件.
- 重现与原银河系结构崩相关的冲击几何形状.
- 通过比尔曼电池效应测量种子磁场生成.
主要成果:
- 在实验室环境中使用Biermann电池效应成功生成种子磁场.
- 证明这些种子场可以通过流来放大.
- 展示的实验结果可扩展到银河间介质.
结论:
- 比尔曼电池是早期宇宙中产生种子磁场的可行机制.
- 动荡可以在7亿年内放大这些种子场,影响银河系的进化.
- 实验室天体物理学提供了关于宇宙磁场起源的宝贵见解.
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