Oka Mitsuo, Birn Joachim, Egedal Jan, Guo Fan, Ergun Robert E, Turner Drew L, Khotyaintsev Yuri, Hwang Kyoung-Joo, Cohen Ian J, Drake James F
Space Sciences Laboratory, University of California Berkeley, 7 Gauss Way, Berkeley, 94720 CA USA.
Center for Space Plasma Physics, Space Science Institute, 4765 Walnut Street, Boulder, 80301 CO USA.
Space Sci Rev. 2023;219(8):75. doi: 10.1007/s11214-023-01011-8. Epub 2023 Nov 7.
Particles are accelerated to very high, non-thermal energies during explosive energy-release phenomena in space, solar, and astrophysical plasma environments. While it has been established that magnetic reconnection plays an important role in the dynamics of Earth's magnetosphere, it remains unclear how magnetic reconnection can further explain particle acceleration to non-thermal energies. Here we review recent progress in our understanding of particle acceleration by magnetic reconnection in Earth's magnetosphere. With improved resolutions, recent spacecraft missions have enabled detailed studies of particle acceleration at various structures such as the diffusion region, separatrix, jets, magnetic islands (flux ropes), and dipolarization front. With the guiding-center approximation of particle motion, many studies have discussed the relative importance of the parallel electric field as well as the Fermi and betatron effects. However, in order to fully understand the particle acceleration mechanism and further compare with particle acceleration in solar and astrophysical plasma environments, there is a need for further investigation of, for example, energy partition and the precise role of turbulence.
在空间、太阳和天体物理等离子体环境中的爆炸式能量释放现象期间，粒子被加速到非常高的非热能。虽然已经确定磁重联在地球磁层动力学中起着重要作用，但磁重联如何能进一步解释粒子加速到非热能仍不清楚。在这里，我们回顾了我们对地球磁层中磁重联导致的粒子加速的理解方面的最新进展。随着分辨率的提高，最近的航天器任务使得能够对各种结构（如扩散区、分界线、喷流、磁岛（通量绳）和偶极化前沿）处的粒子加速进行详细研究。利用粒子运动的引导中心近似，许多研究讨论了平行电场以及费米和贝塔朗日效应的相对重要性。然而，为了充分理解粒子加速机制并进一步与太阳和天体物理等离子体环境中的粒子加速进行比较，例如，需要对能量分配和湍流的精确作用进行进一步研究。
