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   PR # 21116
     We propose to carry out simultaneous observations of some carefully 
    selected Seyferts in the X-ray, ultraviolet, optical and infrared    
    windows, in order to study their broad-band temporal and spectral    
    behavior. Our major effort in the X-ray region will include the study
    of spectral changes during flux variations and the energy dependence 
    of these variations. In the multifrequency broad-band observations   
    the key emphasis would be to investigate the spectral changes, time  
    delays, and characteristic timescales of variations at different     
    frequencies.These studies are fundamental in attempting to understand
    the central engine of active galactic nuclei.                        
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