The Proximity Effect of QSO Metal Line Absorption Systems on Lyman $α$ Forests

The proximity effect of metal line absorption systems in spectra of high redshift quasars and quasar pairs is investigated through the distribution of \Lyalpha forests. No strong proximity effect is found down to 500 km/sec away from a metal line absorption system for lyman $α$ clouds with $13.3\le\log\NHI <13.8$ at a redshift of $\sim 3$. Its implication on properties of high redshift galaxies and \Lyalpha clouds is discussed. More high resolution spectra of high redshift quasars and pairs of quasars (whose lines of sight are separated by $\sim 0.3h^{-1}$ to 1$h^{-1}$ Mpc) are needed so that the proximity effect can be reliably determined for \Lyalpha clouds with various $\NHI$ and down to a closer distance.