Multi-pion production in hadron-nucleus interactions: self-similar or self-affine

Two-dimensional factorial moments analysis of multi-particle production in π - - AgBr interactions at 350 GeV/c with real phase-space partition is performed by considering anisotropy of phase space. It is observed that multi-particle production process is self-affine rather than self-similar. The importance of two-dimensional analysis for the interpretation of data in terms of intermittency is also demonstrated.