The evolution of electron current sheet and formation of secondary islands in guide field reconnection
- 1CAS Key Laboratory of Basic Plasma Physics, Department of Geophysics and Planetary Sciences, University of Science and Technology of China, Hefei 230026, China
- 2State Key Laboratory of Space Weather, Chinese Academy of Sciences, Beijing 100190, China
- 3Beijing National Laboratory of Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100080, China
Abstract. Two-dimensional (2-D) particle-in-cell (PIC) simulations are performed to investigate the evolution of the electron current sheet (ECS) in guide field reconnection. The ECS is formed by electrons accelerated by the inductive electric field in the vicinity of the X line, which is then extended along the x direction due to the imbalance between the electric field force and Ampere force. The tearing instability is unstable when the ECS becomes sufficiently long and thin, and several seed islands are formed in the ECS. These tiny islands may coalesce and form a larger secondary island in the center of the diffusion region.