European Physical Journal C: Particles and Fields (Jul 2023)

UFO 2.0: the ‘Universal Feynman Output’ format

  • Luc Darmé,
  • Céline Degrande,
  • Claude Duhr,
  • Benjamin Fuks,
  • Mark Goodsell,
  • Gudrun Heinrich,
  • Valentin Hirschi,
  • Stefan Höche,
  • Marius Höfer,
  • Joshua Isaacson,
  • Olivier Mattelaer,
  • Thorsten Ohl,
  • Davide Pagani,
  • Jürgen Reuter,
  • Peter Richardson,
  • Steffen Schumann,
  • Hua-Sheng Shao,
  • Frank Siegert,
  • Marco Zaro

DOI
https://doi.org/10.1140/epjc/s10052-023-11780-9
Journal volume & issue
Vol. 83, no. 7
pp. 1 – 28

Abstract

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Abstract We present an update of the Universal FeynRules Output model format, commonly known as the UFO format, that is used by several automated matrix-element generators and high-energy physics software. We detail different features that have been proposed as extensions of the initial format during the last ten years, and collect them in the current second version of the model format that we coin the Universal Feynman Output format. Following the initial philosophy of the UFO, they consist of flexible and modular additions to address particle decays, custom propagators, form factors, the renormalisation group running of parameters and masses, and higher-order quantum corrections.