Perpustakaan Digital ITB

The variability observed in Active Galactic Nuclei (AGN) is thought to be an important characteristic that may provide insight of the physical processes that occurs in the accretion disk in AGN. There are many models that seek to explain this variability, mainly using mass avalanche and diffusion processes without explaining why mass diffusion happened in the disk. Most of these models in turn mention magnetic reconnection as the underlying mechanism of mass diffusion. To further develop the models; here a cellular automata model based on selforganized criticality for magnetic activity in the accretion disk in AGN is studied. This model is based on the similar CA model for solar flare that has been implemented earlier. The result of the simulation was then able to reproduce general appearance from actual light curve. The simulations also create a peak distribution that has similarities with the distribution from observation. However, the power spectral density of the model does meet the expected power law index in the range of 1.5-2.0. Instead, the best variation of the model tested here can only produce the power law index of 0.99.