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arXiv · 0803.3964

Optimizing the Reduction of One-Loop Amplitudes

P. Mastrolia·G. Ossola·C. G. Papadopoulos·R. Pittau
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Abstract

We present an optimization of the reduction algorithm of one-loop amplitudes in terms of master integrals. It is based on the exploitation of the polynomial structure of the integrand when evaluated at values of the loop-momentum fulfilling multiple cut-conditions, as emerged in the OPP-method. The reconstruction of the polynomials, needed for the complete reduction, is rended very versatile by using a projection-technique based on the Discrete Fourier Transform. The novel implementation is applied in the context of the NLO QCD corrections to u d-bar --> W+ W- W+.

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P. Mastrolia, G. Ossola, C. G. Papadopoulos, R. Pittau. 2008-03-27. Optimizing the Reduction of One-Loop Amplitudes. https://doi.org/10.1088/1126-6708%2F2008%2F06%2F030

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