1. Yunnan Observatories, Chinese Academy of Sciences , Kunming 650216, China
2. Key Laboratory for the Structure and Evolution of Celestial Objects, Chinese Academy of Sciences , Kunming 650216, China
3. Hamburger Sternwarte, Universität Hamburg , Gojenbergsweg 112, D-21029 Hamburg, Germany
4. School of Astronomy and Space Science, University of Chinese Academy of Sciences , Beijing 101408, China
5. Department of Physics, School of Science, Xian Jiaotong–Liverpool University (XJTLU) , 111 Renai Rd, Suzhou Dushu Lake Science and Education Innovation District, Suzhou Industrial Park, Suzhou 215123, China
6. Department of Physics, Ariel University , Ariel 40700, Israel