Cold ions of plasmaspheric origin have been observed to abundantly appear in the magnetospheric side of the Earth’s magnetopause. These cold ions could affect the magnetic reconnection processes at the magnetopause by changing the Alfvén velocity and the reconnection rate, while they could also be heated in the reconnection layer during the ongoing reconnections. We report in situ observations from a partially crossing of a reconnection layer near the subsolar magnetopause. During this crossing, step-like accelerating processes of the cold ions were clearly observed, suggesting that the inflow cold ions may be separately accelerated by the rotation discontinuity and slow shock inside the reconnection layer.

已经观察到等离子体层起源的冷离子大量出现在地球磁层顶的磁层一侧。这些冷离子可以通过改变阿尔文速度和重联率来影响磁层顶的磁重联过程，同时它们也可以在正在进行的重联过程中在重联层中被加热。我们报告了来自太阳下磁层顶附近重联层的部分交叉的原位观测。在这次穿越过程中，可以清楚地观察到冷离子的阶梯式加速过程，表明流入的冷离子可能被重联层内部的旋转不连续和慢激波单独加速。