Intensive multiwavelength monitoring campaigns have shown that variability studies provide an excellent tool to investigate the innermost region of active galactic nuclei (AGNs). Detailed studies of the continuum and emission-line variations have revealed new insights about the size, structure, and dynamics of the broad-line region (BLR) in these sources (see Peterson 1993 or Netzer & Peterson 1997 for a review).
Over the last decade, a number of large space-based and ground-based AGN monitoring programs have been undertaken by the International AGN Watch consortium (Alloin et al. 1994) on several Seyfert galaxies, including programs on NGC 3783, NGC4051, NGC 4151, NGC 5548, NGC 7469, Mkn279, Mkn509, Akn564, Fairall 9, and 3C390.3
With the new generation of 10m class telescopes and instruments in earth's orbit it will be possible to address more specific questions and applying more sophisticated methodes like reverberation mappping to data of higher quality.
Variation of the optical spectrum of 3C390.3 from Oct 1994 (low state) until Oct 1995 (high state).
This page created by Matthias Dietrich
Questions or comments should be sent to: Matthias Dietrich
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