中心等离子体片的地向对流型高速流

在GSM坐标系下, 利用TC-1卫星和Cluster/C1卫星上4s分辨率的磁场和热离子探测数据, 对中心等离子体片内的地向对流型高速流进行了统计研究(-19 Re < x< -9 Re, |y| < 10 Re, |z|< 5 Re). 统计结果表明, 地向对流型高速流会在15 Re以内出现``刹车', 在11.5 Re附近时出现``缺失'. 进一步对其速度特征进行统计分析. 结果显示, 在中心等离子体片内的高速流, 其运动方向主要为地向, 晨昏和南北方向的运动明显较弱; 在对流型高速流的地向输运过程中, 其峰值速度没有明显的下降; 在近地13 Re以内, 等离子体片内的地向对流型高速流具有较强的垂直磁力线运动速度. 这意味着对流型高速流在近地15 Re以内的“刹车”不是由高速流晨昏或南北方向的偏转造成的. 高速流在11.5 Re附近时出现的``缺失'可能与在15 Re以内出现``刹车'密切相关. TC-1卫星和Cluster卫星的观测为了解中磁尾重联高速流地向输运过程及亚暴膨胀相触发提供了重要的观测依据. 

Earthward Convective Bursty Flows in the Center Plasma Sheet

With 4 s resolution data of FGM and HIA on Cluster/C1, the earthward Convective Bursty Flows (CBF) inside the region of -19 Re < x < -9 Re, -10 Re < y < 10 Re and -5 Re < z < 5 Re were statistically analyzed in the GSM coordinate. According to the statistical results, the CBF inside the Central Plasma Sheet (CPS) has distinctly ``braking' inside 13~15 Re, and ``absence' around 11.5 Re. The further detail analysis of the velocity of the CBF showed that the CBF move mainly toward the earth. The speed of the CBF has no clear decrease while moving earthward. In addition, the CBF have stronger perpendicular velocity inside 13 Re than outside 15 Re. This implied that the ``absence of BBF' is not due to the deflection of the high-speed flows. The ``braking' and ``absence' of BBF may be closely related. The joint observations of TC-1 and Cluster satellites are important for understanding the transport process of the CBF in the CPS.