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

Mattia Pozzoli

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

High Energy Physics - Phenomenology 2026-08-03 v1

Authors: Mattia Pozzoli

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.

Keywords

two-loop amplitude leading colour approximation top quark pair production W boson associated production QCD differential equations finite field techniques

Cite

@article{arxiv.2608.02527,
  title  = {Two-loop amplitude for $t\bar{t}W$ production at hadron colliders in the leading colour approximation},
  author = {Mattia Pozzoli},
  journal= {arXiv preprint arXiv:2608.02527},
  year   = {2026}
}

Comments

11 pages, 2 figures, 2 tables; contribution to the proceedings of the Loops and Legs in Quantum Field Theory conference (LL2026), April 12-17, 2026, Bayreuth, Germany