23-04U

We study the impact of structural disorder on the universal characteristics of the critical behavior of long-range-interacting systems. As a case study, we use the n-vector model in d space dimensions to consider ferromagnetic ordering in structurally disordered magnets with long-range interaction J(x)~x^-d-σ. It has been demonstrated that there exists such a region of these parameters where the long-range interaction and structural disorder lead to a synergistic effect and to the emergence of a new “random long-range” universality class. We obtain renormalization-group functions and based on them calculate the correlation length critical exponent ν(ε',n) as perturbation theory series in ε'=2σ-d. Quantitative estimates are obtained using resummation of asymptotic series.