%e analyze the possibility of the appearance of long-range correlations of states of quenched defect systems in disordered solids. For randomly distributed defects with a finite number of degenerate internal degrees of freedom such correlations are shown to appear near the defect percolation threshold if they obey certain nearest-neighbor correlation rules. The corresponding efFective Hamiltonian can be viewed as that of a generalized m-component long-range correlated %einrib-Halperin model. Our renormalization-group investigation shows, however, that it asymptotically decomposes into a set of m noninteracting one-component Weinrib-Halperin models. The coordinates of the stable fixed point of this model are determined to O(c~)

The critical behaviour of the generalized (anisotropic) m-component Weinrib-Halperin model is investigated. The critical exponent η and the dynamic exponent z are calculated in d = 4 - ε space dimension in a two- and one-loop approximation, respectively. Using the fermionic formulation we have derived an exact result for the correlation length exponent ν of the two-dimensional Ising model with long-range correlated quenched defects.

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