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arXiv · 0802.1876

On the Rational Terms of the one-loop amplitudes

Giovanni Ossola·Costas G. Papadopoulos·Roberto Pittau
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Abstract

The various sources of Rational Terms contributing to the one-loop amplitudes are critically discussed. We show that the terms originating from the generic (n-4)-dimensional structure of the numerator of the one-loop amplitude can be derived by using appropriate Feynman rules within a tree-like computation. For the terms that originate from the reduction of the 4-dimensional part of the numerator, we present two different strategies and explicit algorithms to compute them.

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Giovanni Ossola, Costas G. Papadopoulos, Roberto Pittau. 2008-02-13. On the Rational Terms of the one-loop amplitudes. https://doi.org/10.1088/1126-6708%2F2008%2F05%2F004

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