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We report on a recently completed VLA survey of Faraday rotation conducted on a sample of 64 radio-bright quasars with redshifts in the range 0.7 $\leq$ z $\leq$ 3.9. Faraday rotation occurs when linearly polarized radio waves traverse a magneto-plasma. Thus this survey probes for magnetized plasmas out to moderately high redshifts. Of the 64 objects in the survey, 12 show damped Ly-$\alpha$ absorption in their optical or UV spectra. Damped Ly-$\alpha$ absorption is interpreted as arising in the gaseous disk of a distant galaxy intervening on the line-of-sight to the quasar. We therefore compare the Faraday rotation properties of these 12 with the remaining 52 quasars to determine if there are magnetic fields associated with these galactic disks. Implications for galactic magnetic field generation and evolution are discussed. This work has been supported by NASA grant NAGW-2119.
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