Shi Peiyun, Scime Earl E, Barbhuiya M Hasan, Cassak Paul A, Adhikari Subash, Swisdak M, Stawarz Julia E
Department of Physics and Astronomy and the Center for KINETIC Plasma Physics, West Virginia University, Morgantown, West Virginia 26506, USA.
Princeton Plasma Physics Laboratory, Princeton, New Jersey 08542, USA.
Phys Rev Lett. 2023 Oct 13;131(15):155101. doi: 10.1103/PhysRevLett.131.155101.
Anisotropic electron heating during electron-only magnetic reconnection with a large guide magnetic field is directly measured in a laboratory plasma through in situ measurements of electron velocity distribution functions. Electron heating preferentially parallel to the magnetic field is localized to one separatrix, and anisotropies of 1.5 are measured. The mechanism for electron energization is identified as the parallel reconnection electric field because of the anisotropic nature of the heating and spatial localization. These characteristics are reproduced in a 2D particle-in-cell simulation and are also consistent with numerous magnetosheath observations. A measured increase in the perpendicular temperature along both separatrices is not reproduced by our 2D simulations. This work has implications for energy partition studies in magnetosheath and laboratory reconnection.
通过对电子速度分布函数的原位测量，在实验室等离子体中直接测量了在具有大引导磁场的纯电子磁重联过程中的各向异性电子加热。优先平行于磁场的电子加热局限于一条磁分界面，测量到的各向异性为1.5。由于加热的各向异性性质和空间局限性，电子加速机制被确定为平行重联电场。这些特征在二维粒子模拟中得到重现，并且也与大量磁鞘观测结果一致。我们的二维模拟没有重现沿两条磁分界面垂直温度的测量增加。这项工作对磁鞘和实验室重联中的能量分配研究具有启示意义。
