Universality classes in the random-storage sandpile model
The avalanche statistics in a stochastic sandpile model where toppling takes place with a probability p is investigated. The limiting case p=1 corresponds to the Bak-Tang-Wiesenfeld (BTW) model with a deterministic toppling rule. Based on the moment analysis of the distribution of avalanche sizes we conclude that for 0<p<p(c) the model belongs to the direct percolation universality class while for p(c)<p<1 it belongs to the BTW universality class, where p(c) is identified with the critical probability for directed percolation in the corresponding lattice.
Vazquez
A
Department of Theoretical Physics, Faculty of Physics, Havana University, Havana 10400, Cuba.
Sotolongo-Costa
O