Simple patterns for nonlinear susceptibilities near T{sub c}

Nonlinear susceptibilities up to the eighth order have been constructed in QCD with two flavors of dynamical quarks. Beyond leading order, they exhibit peaks at the crossover temperature, T{sub c}. By analyzing their behavior in detail, we find that the dominant contributions near T{sub c} come from a set of operators with a remarkably simple topology. Any effective theory of QCD near T{sub c} must be able to explain these regularities.