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arXiv · 2608.02527

Two-loop amplitude for $t\bar{t}W$ production at hadron colliders in the leading colour approximation

Mattia Pozzoli
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Abstract

In this contribution I present the first exact calculation of the leading-colour two-loop QCD amplitude for the associated production of a top-anti-top pair and a W boson. I discuss strategies to address the complexity of the computation, which involves complicated analytic structures, such as nested square roots, elliptic functions, and expressions with a high degree of algebraic complexity. The final result is expressed in terms of a set of special functions, which are evaluated using the method of differential equations, and rational coefficients, evaluated via finite field techniques.

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Mattia Pozzoli. 2026-08-03. Two-loop amplitude for $t\bar{t}W$ production at hadron colliders in the leading colour approximation. https://arxiv.org/abs/2608.02527

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