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arXiv · hep-th/9410081

The heavy quark decomposition of the S-matrix and its relation to the pinch technique

Joannis Papavassiliou·Kostas Philippides·Martin Schaden
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Abstract

We propose a decomposition of the S-matrix into individually gauge invariant sub-amplitudes, which are kinematically akin to propagators, vertices, boxes, etc. This decompsition is obtained by considering limits of the S-matrix when some or all of the external particles have masses larger than any other physical scale. We show at the one-loop level that the effective gluon self-energy so defined is physically equivalent to the corresponding gauge independent self-energy obtained in the framework of the pinch technique. The generalization of this procedure to arbitrary gluonic $n$-point functions is briefly discussed.

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Joannis Papavassiliou, Kostas Philippides, Martin Schaden. 1994-10-11. The heavy quark decomposition of the S-matrix and its relation to the pinch technique. https://doi.org/10.1103/physrevd.51.6364

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