准凯普勒的特征,不同的旋转,自由边界实验室等离子体
V Valenzuela-Villaseca1, L G Suttle1, F Suzuki-Vidal1
1Blackett Laboratory, Imperial College London, London SW7 2BW, United Kingdom.
Physical review letters
|May 27, 2023
概括
使用脉冲动力的实验创造了旋转的等离子体喷射,模拟天体物理现象. 这些喷气在没有边界力的情况下实现了准凯普勒旋转,为盘子和喷气物理提供了洞察力.
科学领域:
- 血物理学的等离子体物理学
- 天体物理流体动力学
- 高能量密度物理学 高能量密度物理学
背景情况:
- 天体物理学盘和喷射是宇宙中至关重要的现象.
- 了解它们的形成和动态需要先进的模拟技术.
- 以前的实验通常依赖于边界力来诱导旋转.
研究的目的:
- 用脉冲动力驱动的等离子体来模拟天体物理盘和喷气的物理.
- 研究不依赖边界力的旋转机制.
- 为了描述产生的旋转等离子体射流的特性.
主要方法:
- 利用脉冲动力驱动的差异旋转等离子体实验.
- 采用了Z电线阵列,通过消耗流的拉杆压力注入角动量.
- 分析了通过组合拉姆,热和磁压的等离子喷气限制.
主要成果:
- 产生了一个旋转的等离子流,具有亚声速旋转 (最大速度为23±3公里/秒).
- 观察到一个近乎凯普勒的旋转速度概况.
- 测量了一个正的雷利分辨率 (κ2r−2.8±0.8 rad2/s2).
- 血完成了0.5-2次旋转,在~150 ns的范围内.
结论:
- 展示了一种模拟天体物理盘和喷气物理学的新方法.
- 证实旋转可以由内部压力梯度驱动,而不仅仅是边界力.
- 观察到的准凯普勒形状和稳定性特征为天体物理模型提供了有价值的数据.
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