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   53025
   X-ray observations of the highest redshift objects yield important
   information on the early formation of deep potential wells and massive
   black holes. Spectral features can also give information on early metal
   enrichment. We propose to observe the most distant detectable object, a
   recently discovered radio-loud quasar at a redshift of 4.73. A
   serendipitous (and off-axis) ROSAT observation of this quasar indicates
   that it will be well detected over the entire 0.5-10 keV energy band of
   ASCA, corresponding to the 3-60 keV band in the rest frame of the
   quasar.
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