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arXiv · hep-ph/9311223

Unstable Particles and Gauge Invariance

Geert Jan van Oldenborgh
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Abstract

When computing the properties of reactions involving unstable charged particles care has to be taken to use a gauge invariant amplitude. In this talk we present methods to (automatically) obtain such an amplitude, both at the tree level and in one-loop calculations, using only a minimal number of diagrams. The numerical difference with gauge variant methods commonly used will be discussed for the case of tree level W pair production.

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Geert Jan van Oldenborgh. 1993-11-04. Unstable Particles and Gauge Invariance. https://arxiv.org/abs/hep-ph/9311223

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