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  • Open Access

Recursive Landau Analysis

Simon Caron-Huot*, Miguel Correia†, and Mathieu Giroux‡

  • Department of Physics, McGill University, 3600 Rue University, Montréal, H3A 2T8 Quebec, Canada

  • *Contact author: schuot@physics.mcgill.ca
  • †Contact author: miguel.ribeirocorreia@mcgill.ca
  • ‡Contact author: mathieu.giroux2@mail.mcgill.ca
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Phys. Rev. Lett. 135, 131603 – Published 24 September, 2025

DOI: https://doi.org/10.1103/8rwk-bnph

Abstract

We propose a recursive method that makes use of the basic principle of unitarity to calculate the Landau singularities of n-point scattering amplitudes directly in kinematic space. For a vast class of Feynman diagrams, the method enables rapid analytic computation of Landau singularities beyond current state-of-the-art technology. This includes new predictions relevant for two- and higher-loop processes in the standard model involving both massive quarks and electroweak particles.

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Outline

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Phys. Rev. Lett. 135, 131603– Published 24 September, 2025
  • Received 16 July 2024
  • Revised 21 May 2025
  • Accepted 26 August 2025
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