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Towards an effective-action approach to fermion-loop corrections

W. Beenakker·A. P. Chapovsky·A. Kanaki·C. G. Papadopoulos·R. Pittau
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Abstract

We present a study of the effective action approach to incorporate higher-order effects in e^+e^- -> n fermions. In its minimal version, the effective action approach is found to exhibit problems with unitarity and high-energy behaviour. We identify the origin of these problems by investigating the zero-mode solutions of the Ward Identities. A numerical analysis of the importance of the zero-mode solutions is presented for four-fermion production processes.

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W. Beenakker, A. P. Chapovsky, A. Kanaki, C. G. Papadopoulos, R. Pittau. 2003-08-12. Towards an effective-action approach to fermion-loop corrections. https://doi.org/10.1016/s0550-3213(03)00545-5

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