[1] Nanjing Univ, Sch Astron & Space Sci, Nanjing 210093, Jiangsu, Peoples R China
[2] Nanjing Univ, Key Lab Modern Astron & Astrophys, Minist Educ, Nanjing 210093, Peoples R China
[3] Kunming Univ, Sch Phys Sci & Technol, Kunming 650214, Yunnan, Peoples R China