On the β-function for σ models with N=1 supersymmetry

By expanding the critical exponent β'(gc) of the supersymmetric σ model on SN, which has been calculated to O(1/N2) in the large N expansion, near two dimensions, we demonstrate that the coefficients of the β-function of σ models with N=1 supersymmetry, in the minimal subtraction scheme, involve the Riemann zeta function and their products at four loops and all subsequent orders in perturbation theory. (orig.)