Supersymmetry, two-dimensional critical phenomena and the tricritical Ising model

We discuss the general properties of supersymmetrical two-dimensional critical phenomena, i.e. superconformal field theory. We first review the consequences of ordinary conformal invariance. We then discuss general features of superconformal invariance and the superdifferential equation that correlation functions in certain theories obey. We give the explicit form of this differential equation in the even sector of the tricritical Ising model at its tricritical point. We find the solution of this equation. The physical realizations of this model, e.g. helium adsorbed on krypton-plated graphite, are the first observable supersymmetric field theories in nature. (orig.)