COVARIANT ONE-LOOP OPERATORS IN OPEN SUPERSTRING THEORY AND FERMION AMPLITUDES

All one-loop primitive operators in the type I open superstring theory are evaluated in the framework of the covariant operator formalism. The redundant degree of freedom associated with the bosonized form of the superghost system are eliminated by making use of the projector proposed by Carow-Watamura et al. The planar, non-orientable and non-planar correlation functions of the superghost system are derived. Their applications to the loop amplitudes with external fermions are discussed. The non-renormalization theorem for these cases is shown covariantly. © 1990.