Regularization of multiloop amplitudes in superstring theory

A singular superconform transformation is found that changes super-Schottky groups to Schottky groups with zero Grassmann modular parameters. Though the new fundamental groups have no Grassmann modular parameters, these parameters are present in superfield vacuum correlators. In points where the transformation is singular the above correlators have poles with residues proportional to Grassmann modular parameters discussed. Unlike the super Schottky group parametrization, in the new parametrization the supermodular group defined for complex (1/1) supermanifolds is split. The above group is, in fact, reduced of the ordinary modular group defined for Riemannian surfaces. It allows to built a supermodular invariant regularization of multi-loop superstring amplitudes