1. Key Laboratory for Computational Astrophysics, National Astronomical Observatories, Chinese Academy of Sciences , Beijing 100012, China
2. School of Astronomy and Space Science, University of Chinese Academy of Sciences , 19 A Yuquan Rd, Shijingshan District, Beijing 100049, China
3. Institute for Computational Cosmology, Department of Physics, Durham University , Science Laboratories, South Road, Durham DH1 3LE, UK
4. Max-Planck-Institut für Astrophysik , Karl-Schwarzschild-Str 1, D-85748 Garching, Germany
5. Instituto de Astrofísica de Canarias , Calle Vía Láctea, E-38205 La Laguna, Tenerife, Spain
6. Departamento de Astrofísica, Universidad de La Laguna , Av. del Astrofísico Francisco Sánchez, E-38206 La Laguna, Tenerife, Spain
7. Department of Physics, University of Helsinki , Gustaf Hällströmin katu 2, FI-00014 Helsinki, Finland