Andrew Lifson
Affiliated
Automating scattering amplitudes with chirality flow
Author
Summary, in English
Recently we introduced the chirality-flow formalism, a method which builds on the spinor-helicity formalism and is inspired by the color-flow idea in QCD. With this formalism, Feynman rules and diagrams are simplified to the extent that it is often possible to immediately, by hand, write down a helicity amplitude given a Feynman diagram. In this paper we show that the method can also speed up numerical evaluation of scattering amplitudes by considering e+e- going to n photons in a MadGraph-based tree-level implementation. We find that the computation time is reduced by roughly a factor ten for six photons, and that it scales better with the number of external particles than the default MadGraph5_aMC@NLO implementation. This performance gain is in part attributed to the more compact Lorentz structures involved, and in part due to a transparent choice of gauge reference vectors which reduces the number of Feynman diagrams considered.
Department/s
- Theoretical Particle Physics - Has been reorganised
Publishing year
2022-06
Language
English
Publication/Series
European Physical Journal C
Volume
82
Issue
6
Links
Document type
Journal article
Publisher
Springer
Topic
- Other Physics Topics
Status
Published
ISBN/ISSN/Other
- ISSN: 1434-6044