MAXI and AGN X-ray Variability

摘要

The X-ray emission from AGN comes from very close to the central black hole and observations of the way in which that emission varies provide the best diagnostic of the origin of the variations, the structure of the emission region and how it scales with mass and accretion rate. Spectral variations also enable us to study the structure of the gas surrounding the central X-ray source and, by comparing X-ray variations with those seen in other wavebands, eg optical, we can deduce the origin of those other-band variations. In this paper I will briefly highlight some recent relevant observations, mainly from the Rossi X-ray Timing Explorer (RXTE), which are relevant to the above topics and will indicate the areas in which future observations with MAXI will improve our understanding.