A Two-Loop Four-Gluon Helicity Amplitude in QCD
نویسندگان
چکیده
We present the two-loop pure gauge contribution to the gluon-gluon scattering amplitude with maximal helicity violation. Our construction of the amplitude does not rely directly on Feynman diagrams, but instead uses its analytic properties in 4 − 2 dimensions. We evaluate the loop integrals appearing in the amplitude through O( ) in terms of polylogarithms.
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