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Journal of High Energy Physics

, 2018:103 | Cite as

Pentagon functions for massless planar scattering amplitudes

  • T. GehrmannEmail author
  • J. M. Henn
  • N. A. Lo Presti
Open Access
Regular Article - Theoretical Physics

Abstract

Loop amplitudes for massless five particle scattering processes contain Feynman integrals depending on the external momentum invariants: pentagon functions. We perform a detailed study of the analyticity properties and cut structure of these functions up to two loops in the planar case, where we classify and identify the minimal set of basis functions. They are computed from the canonical form of their differential equations and expressed in terms of generalized polylogarithms, or alternatively as one-dimensional integrals. We present analytical expressions and numerical evaluation routines for these pentagon functions, in all kinematical configurations relevant to five-particle scattering processes.

Keywords

Perturbative QCD Scattering Amplitudes 

Notes

Open Access

This article is distributed under the terms of the Creative Commons Attribution License (CC-BY 4.0), which permits any use, distribution and reproduction in any medium, provided the original author(s) and source are credited.

Supplementary material

13130_2018_9201_MOESM1_ESM.zip
ESM 1 (ZIP 1257 kb)

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Copyright information

© The Author(s) 2018

Authors and Affiliations

  1. 1.Physik-InstitutUniversität ZürichZürichSwitzerland
  2. 2.PRISMA Cluster of Excellence, Institute of PhysicsJohannes Gutenberg UniversityMainzGermany
  3. 3.MPI für PhysikWerner-Heisenberg-InstitutMünchenGermany
  4. 4.Institute for Particle Physics PhenomenologyDurham UniversityDurhamU.K.

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