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   PR # 43049
   We propose a deep ASCA observation of one of our deep ROSAT fields
   Our goals are: (i) to measure individual and summed X-ray spectra of
   the ROSAT sources in the 2-10keV band, in order to (ii) establish the
   contribution of ROSAT AGN and X-ray luminous galaxies to the harder
   XRB; (iii) to search for 2-10 keV emission from other, heavily
   absorbed AGN or other sources. We focus our attention on a deep ROSAT
   field where we have achieved a greater than 80\% optical
   identification rate including redshift information.
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