Ion Velocity Distributions in a Non-Stationary Perpendicular Shock
YANG Zhong-Wei1,2, LU Quan-Ming1,2, WANG Shui1
1CAS Key Laboratory of Basic Plasma Physics, School of Earth and Space Sciences, University of Science and Technology of China, Hefei 2300262State Key Laboratory of Space Weather, Chinese Academy of Sciences, Beijing 100190
Ion Velocity Distributions in a Non-Stationary Perpendicular Shock
YANG Zhong-Wei1,2, LU Quan-Ming1,2, WANG Shui1
1CAS Key Laboratory of Basic Plasma Physics, School of Earth and Space Sciences, University of Science and Technology of China, Hefei 2300262State Key Laboratory of Space Weather, Chinese Academy of Sciences, Beijing 100190
摘要Previous particle-in-cell simulations have evidenced that supercritical, quasi-perpendicular shocks are non-stationary. By separating the incident ions into reflected (R) and directly transmitted (DT) parts, we investigate the ion distributions in a non-stationary perpendicular shock. The upstream ion distributions have two parts corresponding to the R and incident ions respectively, while the R ions have higher energy. The downstream ions have a core-ring distribution. The core and ring parts correspond to the DT and R ions, respectively. The ion distributions depend largely on the non-stationary shock structure. The percentage of the reflected ions cyclically varies in time with a period equal to the shock self-reformation cycle, and the number of the R ions increases with the steepness of the shock ramp.
Abstract：Previous particle-in-cell simulations have evidenced that supercritical, quasi-perpendicular shocks are non-stationary. By separating the incident ions into reflected (R) and directly transmitted (DT) parts, we investigate the ion distributions in a non-stationary perpendicular shock. The upstream ion distributions have two parts corresponding to the R and incident ions respectively, while the R ions have higher energy. The downstream ions have a core-ring distribution. The core and ring parts correspond to the DT and R ions, respectively. The ion distributions depend largely on the non-stationary shock structure. The percentage of the reflected ions cyclically varies in time with a period equal to the shock self-reformation cycle, and the number of the R ions increases with the steepness of the shock ramp.
YANG Zhong-Wei;LU Quan-Ming;WANG Shui. Ion Velocity Distributions in a Non-Stationary Perpendicular Shock[J]. 中国物理快报, 2010, 27(1): 19601-019601.
YANG Zhong-Wei, LU Quan-Ming, WANG Shui. Ion Velocity Distributions in a Non-Stationary Perpendicular Shock. Chin. Phys. Lett., 2010, 27(1): 19601-019601.
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2010, Vol. 27 
