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Pentagon functions for massless planar scattering amplitudes

Journal of High Energy Physics volume 2018, Article number: 103 (2018) Cite this article

A preprint version of the article is available at arXiv.

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.

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Affiliations

  1. Physik-Institut, Universität Zürich, Wintherturerstrasse 190, CH-8057, Zürich, Switzerland

    T. Gehrmann

  2. PRISMA Cluster of Excellence, Institute of Physics, Johannes Gutenberg University, D-55099, Mainz, Germany

    J. M. Henn

  3. MPI für Physik, Werner-Heisenberg-Institut, München, Germany

    J. M. Henn

  4. Institute for Particle Physics Phenomenology, Durham University, Durham, DH1 3LE, U.K.

    N. A. Lo Presti

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  1. T. Gehrmann
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  2. J. M. Henn
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Correspondence to T. Gehrmann.

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ArXiv ePrint: 1807.09812

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Gehrmann, T., Henn, J.M. & Lo Presti, N.A. Pentagon functions for massless planar scattering amplitudes. J. High Energ. Phys. 2018, 103 (2018). https://doi.org/10.1007/JHEP10(2018)103

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Keywords

  • Perturbative QCD
  • Scattering Amplitudes