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Multi-leg calculations with the GRACE/1-LOOP system. --Toward Radiative Corrections to e+e- -> mu nu-bar u d-bar --

F. Boudjema·J. Fujimoto·T. Ishikawa·T. Kaneko·K. Kato·Y. Kurihara·Y. Shimizu
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Abstract

We performed the calculation of the full O(alpha) corrections to e+e- -> mu- nu-bar u d-bar with the help of the GRACE/1-LOOP system. We discuss how a finite decay width introduces a serious gauge invariance breaking, particularly for infrared 5-point functions. This is related to the way the reduction of those functions is performed and to the treatment of the width in the reduction.

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F. Boudjema, J. Fujimoto, T. Ishikawa, T. Kaneko, K. Kato, Y. Kurihara, Y. Shimizu. 2004-07-07. Multi-leg calculations with the GRACE/1-LOOP system. --Toward Radiative Corrections to e+e- -> mu nu-bar u d-bar --. https://doi.org/10.1016/j.nuclphysbps.2004.09.016

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