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Techniques for one-loop tensor integrals in many-particle processes

A. Denner·S. Dittmaier
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Abstract

We briefly sketch the methods for a numerically stable evaluation of tensor one-loop integrals that have been used in the calculation of the complete electroweak one-loop corrections to $\Pep\Pem\to4 $fermions. In particular, the improvement of the new methods over the conventional Passarino--Veltman reduction is illustrated for some 4-point integrals in the delicate limits of small Gram (and other kinematical) determinants.

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A. Denner, S. Dittmaier. 2006-01-11. Techniques for one-loop tensor integrals in many-particle processes. https://doi.org/10.1016/j.nuclphysbps.2006.03.008

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