The changing-look (CL) behavior in active galactic nuclei (AGNs) is characterized by dramatic fluctuations in the overall brightness of sources, leading to restructuring of circum-nuclear environments such as the inner accretion geometry, broad line region (BLR), and outflows. They offer a rare opportunity to witness accretion state transitions in real time, akin to those seen in stellar-mass X-ray binaries (XRBs). In this talk, I will present a decade-long multiwavelength study of the Seyfert galaxy, which captures a complete spectral state transition--from a faint, hard X-ray phase to a bright, UV- and soft X-ray-dominated state within just ~10 years. Using diagnostics like the X-ray loudness parameter and the hardness-intensity diagram, we identify a critical Eddington ratio (~ 0.02) marking the onset of inner accretion flow restructuring. These findings provide strong evidence that CLAGNs trace accretion physics analogous to XRBs, scaled up in mass but compressed in time.

Location: Spořilov -101