On-the-fly reduction of open loops

@article{Buccioni2018OntheflyRO,
  title={On-the-fly reduction of open loops},
  author={Federico Buccioni and S. Pozzorini and Max F. Zoller},
  journal={The European Physical Journal C},
  year={2018},
  volume={78},
  pages={1-35}
}
Building on the open-loop algorithm we introduce a new method for the automated construction of one-loop amplitudes and their reduction to scalar integrals. The key idea is that the factorisation of one-loop integrands in a product of loop segments makes it possible to perform various operations on-the-fly while constructing the integrand. Reducing the integrand on-the-fly, after each segment multiplication, the construction of loop diagrams and their reduction are unified in a single numerical… 

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