A new method for one-loop amplitude generation and reduction in OpenLoops

@article{Buccioni2018ANM,
  title={A new method for one-loop amplitude generation and reduction in OpenLoops},
  author={Federico Buccioni and S. Pozzorini and M. Zoller},
  journal={arXiv: High Energy Physics - Phenomenology},
  year={2018},
  pages={024}
}
We describe a new method for the automated construction of one-loop amplitudes based on the open-loop algorithm, where various operations are performed on-the-fly while constructing the integrand. In particular, an on-the-fly reduction interleaved with the construction steps of the amplitude keeps the maximum tensor rank in the loop momentum at two throughout the algorithm, thus drastically reducing the complexity of the calculation. The full reduction to scalar integrals is unified with the… Expand

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