用英文给出HiBALs的定义在括号里标注参考文献不能抄袭已有参考文献。

HiBALs (High Ionization Broad Absorption Line Quasars) are a type of quasar with broad absorption lines in their spectra that are produced by highly ionized gas moving at high velocities (Weymann et al., 1991). These absorption lines are believed to arise from outflows of gas from the accretion disk surrounding the supermassive black hole in the center of the quasar (Ganguly et al., 2007). HiBALs are distinguished from other types of BAL quasars by the presence of absorption lines from highly ionized elements such as C IV, N V, and O VI (Hamann et al., 1997). They are thought to represent a transitional phase in the evolution of quasars, where the gas outflows are still in the early stages of development (Ganguly et al., 2007)