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arXiv · 2009.07803

Pentagon Functions for Scattering of Five Massless Particles

Dmitry Chicherin·Vasily Sotnikov
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Abstract

We complete the analytic calculation of the full set of two-loop Feynman integrals required for computation of massless five-particle scattering amplitudes. We employ the method of canonical differential equations to construct a minimal basis set of transcendental functions, pentagon functions, which is sufficient to express all planar and nonplanar massless five-point two-loop Feynman integrals in the whole physical phase space. We find analytic expressions for pentagon functions which are manifestly free of unphysical branch cuts. We present a public library for numerical evaluation of pentagon functions suitable for immediate phenomenological applications.

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Dmitry Chicherin, Vasily Sotnikov. 2020-09-16. Pentagon Functions for Scattering of Five Massless Particles. https://doi.org/10.1007/jhep12(2020)167

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