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Energetic particles in laboratory, space and astrophysical plasmas

机译：实验室，空间和天体物理等离子体中的精力充沛的粒子

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Some recent studies of energetic particles in laboratory, space and astrophysical plasmas are discussed, and a number of common themes identified. Such comparative studies can elucidate the underlying physical processes. For example microwave bursts observed during edge localised modes (ELMs) in the mega amp spherical tokamak (MAST) can be attributed to energetic electrons accelerated by parallel electric fields associated with the ELMs. The very large numbers of electrons known to be accelerated in solar flares must also arise from parallel electric fields, and the demonstration of energetic electron production during ELMs suggests close links at the kinetic level between ELMs and flares. Energetic particle studies in solar flares have focussed largely on electrons rather than ions, since bremsstrahlung from deka-keV electrons provides the best available explanation of flare hard x-ray emission. However ion acceleration (but not electron acceleration) has been observed during merging startup of plasmas in MAST with dimensionless parameters similar to those of the solar corona during flares. Recent measurements in the Earth's radiation belts demonstrate clearly a direct link between ion cyclotron emission (ICE) and fast particle population inversion, supporting the hypothesis that ICE in tokamaks is driven by fast particle distributions of this type. Shear Alfven waves in plasmas with beta less than the electron to ion mass ratio have a parallel electric field that, in the solar corona, could accelerate electrons to hard x-ray-emitting energies; an extension of this calculation to plasmas with Alfven speed arbitrarily close to the speed of light suggests that the mechanism could play a role in the production of cosmic ray electrons.
机译：讨论了在实验室，空间和天体物理等离子体中的最近对能量粒子的研究，并确定了许多常见主题。这种比较研究可以阐明潜在的物理过程。例如，在Mega AMP球形TOKAMAK（MAST）中的边缘局部模式（ELM）期间观察到的微波突发可归因于由与ELM相关联的平行电场加速的能量电子。已知在太阳耀斑中加速的非常大量的电子必须从并行电场出现，并且在ELM期间的能量电子产生的演示表明在ELM和喇叭口之间的动力学水平处的紧密联系。由于来自Deka-Kev电子的Bremsstrahlung，太阳耀斑的精力粒子研究主要针对电子而不是离子，从而提供了光晕硬X射线发射的最佳可用解释。然而，在将桅杆中的等离子体的启动中合并了与耀斑期间的太阳电晕相似的无量纲参数，已经观察到离子加速度（但不是电子加速）。地球辐射带中的最近测量结果清楚地表明了离子回旋缩（冰）和快速粒子群反演之间的直接联系，支持Tokamaks的冰是通过这种类型的快速粒子分布驱动的假设。剪切Alfven在等离子体中的剪切Alfven波的β小于电子对离子质量比的电场具有平行电场，在太阳能电晕中，可以将电子加速到硬X射线发射能量;与Alfven速度的等离子体的延伸是任意接近光速的Alfven速度表明该机制可以在宇宙射线电子的生产中发挥作用。

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