Correlations and scaling in the outflow statistics of a sandpile automaton

We study numerically the outflow of a two-dimensional sandpile cellular automation. Motivated by recent experiments we calculated the correlations in the sizes of the outflow avalanches and obtained for short times exponential decay. For long times a quasiperiodic behavior was observed with the characteristic time proportional to the number of sites in the system. The latter feature is attributed to the Abelian character of the considered model. The size distribution of the outflow avalanches can be described excellently by multifractal scaling.