091243

Understanding the nature and origin of spectral variability provides us with key information about the accretion-outflow mechanism in active galactic nuclei (AGN). Changing-look AGN show the most striking cases of spectral variability in AGN. NGC 3516 is a remarkable Seyfert-1 galaxy which over the last decade has undergone major optical-UV-X-ray spectral transformations classifying it as a changing-look AGN. The extensive Swift monitoring of NGC 3516 shows that it is currently in a state of long-term transition between the extremely low-flux state and the historical high-flux state. The proposed joint NuSTAR (60 ks) and XMM-Newton (60 ks) observations of this transition state aim to gain new insights into the mechanism of transition between the different states of the changing-look AGN. [truncated! Please see actual data for full text]