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   PR # 42115
   We propose 4x40 ksec observations of NGC 3783 to determine the
   location of, and constrain the physical conditions within the strong
   ``warm absorber'' surrounding this source. This object is ideal for
   such a study since it has exhibited a clear correlation of ionization
   parameter with continuum flux level, and there is an OVII emission
   line at 0.57 keV in the AO1 spectrum with an intensity consistent
   with plausible physical models. The proposed observations will allow
   us to place stringent constraints on the correlations between the
   X-ray continuum and both the ionized absorber and emitter. Thus we be
   able to determine the location of the warm absorber along with the
   density, ionization state and volume of the ionized gas.
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