Noise in Disordered Systems: Higher Order Spectra in Avalanche Models
  We present a novel analytic calculation of the Haar power spectra, and various higher order spectra, of mean field avalanche models. We also compute these spectra from a simulation of the zero-temperature mean field RFIM and infinite range RFIM model for $d = 3$. We compare the results and obtain novel exponents. 
Amit P. Mehta, Karin A. Dahmen, M. W. Weissman, Tim Wotherspoon