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Momentum expansion of massive two-loop Feynman graphs around a finite value

A. Ghinculov·Y. P. Yao
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Abstract

We give an algorithm for obtaining expansions of massive two-loop Feynman graphs in powers of the external momentum around a finite, nonzero value of the momentum. This is based on our general two-loop formalism to reduce massive two-loop graphs with renormalizable interactions into a standard set of special functions. After the algebraic reduction, the final results are obtained by numerical integration. We apply the expansion algorithm to treat the top-dependent corrections of O(g^2 alpha_s) to the b quark self-energy and extract its momentum expansion on-shell.

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A. Ghinculov, Y. P. Yao. 1999-10-20. Momentum expansion of massive two-loop Feynman graphs around a finite value. https://doi.org/10.1142/s0217732300000499

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