Document Type


Publication Date

Spring 2021


I will report decade-long monitoring campaigns with the NASA Neil-Gehrels Swift mission of about 100 Active Galactic Nuclei (AGN). Swift has started with monitoring some AGN since 2005. This long-term monitoring project has enabled us to catch AGN in extreme high and low X-ray flux states allowing to trigger follow-up observations by XMM-Newton, NuSTAR, HST. While this program has led in the past to at least one trigger per year, no AGN was found with extreme variability. I will also give a brief overview of the causes of this extreme variability.



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