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Analytic Form of the Two-Loop Planar Five-Gluon All-Plus-Helicity Amplitude in QCD
T Gehrmann1, J M Henn2, N A Lo Presti1
1Department of Physics, University of Zürich, Winterthurerstrasse 190, CH-8057 Zürich, Switzerland.
Abstract:
Virtual two-loop corrections to scattering amplitudes are a key ingredient to precision physics at collider experiments. We compute the full set of planar master integrals relevant to five-point functions in massless QCD, and use these to derive an analytical expression for the two-loop five-gluon all-plus-helicity amplitude. After subtracting terms that are related to the universal infrared and ultraviolet pole structure, we obtain a remarkably simple and compact finite remainder function, consisting only of dilogarithms.
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