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arXiv · hep-ph/9712449

A new method for the calculation of massive multiloop diagrams

K. Knecht·H. Verschelde
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Abstract

Starting from the parametric representation of a Feynman diagram, we obtain it's well defined value in dimensional regularisation by changing the integrals over parameters into contour integrals. That way we eventually arrive at a representation consisting of well-defined compact integrals. The result is a simple transformation of the integrand which gives the analytic continuation of a wide class of Feynmanintegrals. The algorithm will especially be fit for numerical calculation of general massive multi-loop integrals. An important advantage of this method is that it allows us to calculate both infinite and finite parts independently.

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K. Knecht, H. Verschelde. 1998-03-06. A new method for the calculation of massive multiloop diagrams. https://arxiv.org/abs/hep-ph/9712449

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