State Key Laboratory of Space Weather National Space Science Center Chinese Academy of Sciences Beijing 100190 China;
State Key Laboratory of Space Weather National Space Science Center Chinese Academy of Sciences Beijing 100190 China;
State Key Laboratory of Space Weather National Space Science Center Chinese Academy of Sciences Beijing 100190 China;
State Key Laboratory of Space Weather National Space Science Center Chinese Academy of Sciences Beijing 100190 China;
Department of Engineering Physics Tsinghua University Beijing 100084 China;
Earth plasmasphere He+density; algebraic reconstruction technique; image total variation; north–south symmetry; SXI image reconstruction; SMILE mission;