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arXiv · hep-th/9411015

On the computation of one-loop amplitudes with external fermions in 4d heterotic superstrings

A. Pasquinucci·K. Roland
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Abstract

We present the technical tools needed to compute any one-loop amplitude involving external spacetime fermions in a four-dimensional heterotic string model a` la Kawai-Lewellen-Tye. As an example, we compute the one-loop three-point amplitude with one "photon" and two external massive fermions ("electrons"). As a check of our computation, we verify that the one-loop contribution to the Anomalous Magnetic Moment vanishes if the model has spacetime supersymmetry, as required by the supersymmetric sum rules.

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A. Pasquinucci, K. Roland. 1994-11-02. On the computation of one-loop amplitudes with external fermions in 4d heterotic superstrings. https://doi.org/10.1016/0550-3213(95)00053-u

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