Abstract
We present a new approach to the reduction of one-loop amplitudes obtained by reconstructing the tensorial expression of the scattering amplitudes. The reconstruction is performed at the integrand level by means of a sampling in the integration momentum. There are several interesting applications of this novel method within existing techniques for the reduction of one-loop multi-leg amplitudes: to deal with numerically unstable points, such as in the vicinity of a vanishing Gram determinant; to allow for a sampling of the numerator function based on real values of the integration momentum; to optimize the numerical reduction in the case of long expressions for the numerator functions.
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ArXiv ePrint: 1008.2441
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Heinrich, G., Ossola, G., Reiter, T. et al. Tensorial reconstruction at the integrand level. J. High Energ. Phys. 2010, 105 (2010). https://doi.org/10.1007/JHEP10(2010)105
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DOI: https://doi.org/10.1007/JHEP10(2010)105