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arXiv · 0812.3686

Direct numerical integration of one-loop Feynman diagrams for N-photon amplitudes

Wei Gong·Zoltan Nagy·Davison E. Soper
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Abstract

One approach to the calculation of cross sections for infrared-safe observables in high energy collisions at next-to-leading order is to perform all of the integrations, including the virtual loop integration, by Monte Carlo numerical integration. In a previous paper, two of us have shown how one can perform such a virtual loop integration numerically after first introducing a Feynman parameter representation. In this paper, we perform the integration directly, without introducing Feynman parameters, after suitably deforming the integration contour. Our example is the N-photon scattering amplitude with a massless electron loop. We report results for N = 6 and N = 8.

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Wei Gong, Zoltan Nagy, Davison E. Soper. 2008-12-19. Direct numerical integration of one-loop Feynman diagrams for N-photon amplitudes. https://doi.org/10.1103/physrevd.79.033005

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