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arXiv · 1111.5206

Scattering Amplitudes with Open Loops

Fabio Cascioli·Philipp Maierhöfer·Stefano Pozzorini
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Abstract

We introduce a new technique to generate scattering amplitudes at one loop. Traditional tree algorithms, which handle diagrams with fixed momenta, are promoted to generators of loop-momentum polynomials that we call open loops. Combining open loops with tensor-integral and OPP reduction results in a fully flexible, very fast, and numerically stable one-loop generator. As demonstrated with non-trivial applications, the open-loop approach will permit to obtain precise predictions for a very wide range of collider processes.

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Fabio Cascioli, Philipp Maierhöfer, Stefano Pozzorini. 2012-03-05. Scattering Amplitudes with Open Loops. https://doi.org/10.1103/physrevlett.108.111601

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