The automated computation of tree-level and next-to-leading order differential cross sections, and their matching to parton shower simulations

  title={The automated computation of tree-level and next-to-leading order differential cross sections, and their matching to parton shower simulations},
  author={Johan Alwall and R. Frederix and Stefano Frixione and Valentin Hirschi and Fabio Maltoni and Olivier Mattelaer and Hua-Sheng Shao and Tim Stelzer and Paolo Torrielli and Marco Zaro},
  journal={Journal of High Energy Physics},
A bstractWe discuss the theoretical bases that underpin the automation of the computations of tree-level and next-to-leading order cross sections, of their matching to parton shower simulations, and of the merging of matched samples that differ by light-parton multiplicities. We present a computer program, MadGraph5 aMC@NLO, capable of handling all these computations — parton-level fixed order, shower-matched, merged — in a unified framework whose defining features are flexibility, high level… 

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