1. School of Physics and Technology, Wuhan University , Wuhan, Hubei 430072, China
2. Advanced Institute of Natural Sciences, Beijing Normal University , Zhuhai 519087, China
3. Purple Mountain Observatory, Chinese Academy of Sciences , Nanjing 210023, China
4. School of Astronomy and Space Sciences, University of Science and Technology of China , Hefei 230026, China
5. Department of Astronomy, Beijing Normal University , Beijing 100875, China
6. Guangxi Key Laboratory for Relativistic Astrophysics, School of Physical Science and Technology, Guangxi University , Nanning 530004, China