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arXiv · 2102.13450

Two-loop leading colour QCD helicity amplitudes for top quark pair production in the gluon fusion channel

Simon Badger·Ekta Chaubey·Heribertus Bayu Hartanto·Robin Marzucca
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Abstract

We present a complete set of analytic helicity amplitudes for top quark pair production via gluon fusion at two-loops in QCD. For the first time, we include corrections due to massive fermion loops which give rise to integrals over elliptic curves. We present the results of the missing master integrals needed to compute the amplitude and obtain an analytic form for the finite remainders in terms of iterated integrals using rationalised kinematics and finite field sampling. We also study the numerical evaluation of the iterated integrals.

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Simon Badger, Ekta Chaubey, Heribertus Bayu Hartanto, Robin Marzucca. 2021-02-26. Two-loop leading colour QCD helicity amplitudes for top quark pair production in the gluon fusion channel. https://doi.org/10.1007/jhep06(2021)163

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