1. Key Laboratory of Optical Astronomy, National Astronomical Observatories, Chinese Academy of Sciences, Beijing 100101, China
2. Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000, China
3. Department of Astronomy, Beijing Normal University, Beijing 100875, China
4. Key Laboratory of Computational Physics, Institute of Applied Physics and Computational Mathematics, P.O. Box 8009, Beijing 100088, China
5. HEDPS, Center for Applied Physics and Technology, and College of Engineering, Peking University, Beijing 100871, China
6. Department of Astronomy, Tsinghua University, Beijing 100084, China