An Algorithm for Small Momentum Expansion of Feynman Diagrams
نویسنده
چکیده
An algorithm for obtaining the Taylor coefficients of an expansion of Feynman diagrams is proposed. It is based on recurrence relations which can be applied to the propagator as well as to the vertex diagrams. As an application, several coefficients of the Taylor series expansion for the two-loop non-planar vertex and two-loop propagator diagrams are calculated. The results of the numerical evaluation of these diagrams using conformal mapping and Padé approximants are given.
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