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   PR # 12168
    Observations have shown that Seyfert galaxies contain substantial am-
    ounts of reprocessing material in the vicinity of the active nucleus,
    significantly modifying the continuum form. To understand the physics
    of the primary emission and reprocessing mechanisms we need to decon-
    volve these spectral components.NGC3783 shows the strongest signature
    of warm absorption observed to date and we propose 2 pointings to
    study the warm absorber & its response to continuum flux variations.
    PSPC observations of Mkn766 show rapid X-ray spectral variability con
    sistent with a rapid response of the warm absorber to continuum
    changes.We consider these 2 sources to be the best targets to further
    our understanding of the physical state of the circumnuclear material
   in Seyfert-1s.
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