supported by the Strategic Priority Research Program"The emergence of Cosmological Structures"of the Chinese Academy of Sciences(Grant No.XDB09000000);the National Natural Science Foundation of China(Grant Nos.11373008,11133006 and 11361140347)
The ultraviolet broad absorption lines have been seen in the spectra of quasars at high redshift, and are generally considered to be caused by outflows with velocities from thousands kilometers per second to one tenth...