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arXiv · 1404.6493

NNLO QCD subtraction for top-antitop production in the $q\bar{q}$ channel

Gabriel Abelof·Aude Gehrmann-De Ridder·Philipp Maierhöfer·Stefano Pozzorini
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Abstract

We present the computation of the double real and real-virtual contributions to top-antitop pair production in the quark-antiquark channel at leading colour. The $q \bar q \to t \bar{t} g$ amplitudes contributing to the real-virtual part are computed with OpenLoops, and their numerical stability in the soft and collinear regions is found to be sufficiently high to perform a realistic NNLO calculation in double precision. The subtraction terms required at real-real and real-virtual levels are constructed within the antenna subtraction formalism extended to deal with the presence of coloured massive final state particles. We show that those subtraction terms approximate the real-real and real-virtual matrix elements in all their singular limits.

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Gabriel Abelof, Aude Gehrmann-De Ridder, Philipp Maierhöfer, Stefano Pozzorini. 2014-08-04. NNLO QCD subtraction for top-antitop production in the $q\bar{q}$ channel. https://doi.org/10.1007/jhep08(2014)035

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