1. School of Astronomy and Space Science, Nanjing University, Nanjing, Jiangsu 210093, People’s Republic of China
2. Key Laboratory of Modern Astronomy and Astrophysics (Nanjing University), Ministry of Education, Nanjing 210093, People’s Republic of China
3. School of Physical Science and Technology, Kunming University, Kunming 650214, People’s Republic of China