Speaker
Description
Active galactic nuclei (AGN) are powered by accretion onto a supermassive black hole (SMBH), but the structure of this flow is not well understood. Standard accretion disc models match to zeroth order in predicting substantial energy dissipated in optically-thick material, producing a strong blue/UV continuum. More detailed comparisons to the observed spectral shapes fail, along with a complete failure in reproducing their variable nature. In this talk I will present ongoing work aimed at addressing these issues. I will demonstrate that the data currently suggest a highly turbulent accretion disc in AGN on short (weeks-months) timescales, in contrast to standard theory. Using detailed physically motivated modelling, I will further demonstrate how multiwavelength variability data can be used to unveil the physical structure and conditions of this turbulent accretion flow, looking ahead to upcoming monitoring campaigns and LSST. Finally, I will show recent results which suggest an evolution in the structure of the inner flow on short (~50 day) time-scales, significantly challenging our current picture of accretion in AGN.