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We present the two-loop helicity amplitudes contributing to the next-to-next-to-leading order QCD predictions for W-boson production in association with two photons at the Large Hadron Collider. We derived compact analytic expressions for…

High Energy Physics - Phenomenology · Physics 2024-09-27 Simon Badger , Heribertus Bayu Hartanto , Zihao Wu , Yang Zhang , Simone Zoia

The ability to calculate analytic full-colour two-to-three two-loop helicity amplitudes in massless QCD has been a recent triumph of the field, driving phenomenology towards one percent precision. In this contribution, we focus on the…

High Energy Physics - Phenomenology · Physics 2023-10-31 Ryan Moodie

We present a new method for computing multi-loop scattering amplitudes in Quantum Field Theory. It extends the Generalized Unitarity method by constraining not only the integrand of the amplitude but also its full integrated form. Our…

High Energy Physics - Theory · Physics 2025-12-18 Piotr Bargiela

We apply the solution to the recursion relation for the double-off-shell quark current to the problem of computing one loop amplitudes with an arbitrary number of gluons. We are able to compute amplitudes for photon-gluon scattering,…

High Energy Physics - Phenomenology · Physics 2009-10-22 Gregory Mahlon

We present analytical results for all six-photon helicity amplitudes. For the computation of this loop induced process two recently developed methods, based on form factor decomposition and on multiple cuts, have been used. We obtain…

High Energy Physics - Phenomenology · Physics 2008-11-26 T. Binoth , T. Gehrmann , G. Heinrich , P. Mastrolia

The associated production of a photon and a top-antitop quark pair ($t\bar{t}\gamma$) is important for measuring the top-quark charge and probing the top-photon interaction, and it requires improved theoretical predictions. We focus on the…

High Energy Physics - Phenomenology · Physics 2025-10-03 Guoxing Wang , Li Lin Yang

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…

High Energy Physics - Phenomenology · Physics 2021-07-14 Simon Badger , Ekta Chaubey , Heribertus Bayu Hartanto , Robin Marzucca

We compute the leading colour contributions to five-gluon scattering at two loops in massless QCD. The integrands of all independent helicity amplitudes are evaluated using d-dimensional generalised unitarity cuts and finite field…

High Energy Physics - Phenomenology · Physics 2018-03-07 Simon Badger , Christian Brønnum-Hansen , Heribertus Bayu Hartanto , Tiziano Peraro

We compute three-loop QCD corrections to the scattering amplitude of a Higgs boson and three partons interfered with its tree level counterpart. Specifically, we derive our results in the generalized leading color limit. Our results are…

High Energy Physics - Phenomenology · Physics 2025-04-10 Xiang Chen , Xin Guan , Bernhard Mistlberger

We present the two-loop QCD helicity amplitudes for quark-quark and quark-antiquark scattering. These amplitudes are relevant for next-to-next-to-leading order corrections to (polarized) jet production at hadron colliders. We give the…

High Energy Physics - Phenomenology · Physics 2014-01-27 Abilio De Freitas , Zvi Bern

We compute the two-loop master integrals for leading-color QCD scattering amplitudes including a closed light-quark loop in $t\bar{t}H$ production at hadron colliders. Exploiting numerical evaluations in modular arithmetic, we construct a…

High Energy Physics - Phenomenology · Physics 2024-07-18 F. Febres Cordero , G. Figueiredo , M. Kraus , B. Page , L. Reina

The self-couplings of the electroweak gauge bosons are probed at hadron colliders through the production of a massive gauge boson and a photon. To extend the theoretical description of this type of final states towards…

High Energy Physics - Phenomenology · Physics 2020-12-09 Thomas Gehrmann , Lorenzo Tancredi

We find that scattering amplitudes in massive scalar QCD can manifest the duality between color and kinematics at loop-level. Specifically we construct the one-loop integrands for four-point scattering between two distinct massive scalars,…

High Energy Physics - Theory · Physics 2021-02-10 John Joseph M. Carrasco , Ingrid A. Vazquez-Holm

We present the first benchmark evaluation of the two-loop finite remainders for the production of a top-quark pair in association with a jet at hadron colliders in the gluon channel. We work in the leading colour approximation, and perform…

High Energy Physics - Phenomenology · Physics 2025-03-14 Simon Badger , Matteo Becchetti , Colomba Brancaccio , Heribertus Bayu Hartanto , Simone Zoia

I review the recent progress in the evaluation of two-loop massive QCD amplitudes necessary for the description of hadronic scattering processes at the LHC. I put a special emphasis on the case of top-quark final states.

High Energy Physics - Phenomenology · Physics 2008-11-26 M. Czakon

I discuss the recent advances in the computation of two-loop scattering amplitudes for five-particle processes. The latter are fundamental ingredients to obtain predictions at the next-to-next-to-leading order (NNLO) in QCD for many…

High Energy Physics - Phenomenology · Physics 2023-10-09 Simone Zoia

We detail the calculation of two-loop all-plus helicity amplitudes for pure Yang-Mills theory. The four dimensional unitarity methods and augmented recursion techniques we have developed, together with a knowledge of the singular structure…

High Energy Physics - Theory · Physics 2017-12-27 David C. Dunbar , John H. Godwin , Guy R. Jehu , Warren B. Perkins

We calculate all the four-photon helicity amplitudes at the one-loop level in a massive theory using multiple-cut methods. The amplitudes are derived in scalar QED, QED and $\textrm{QED}^{\caln =1}$ theories. We will see the origin of…

High Energy Physics - Phenomenology · Physics 2009-02-02 Christophe Bernicot

We here use our non-perturbative, cluster decomposable relativistic scattering formalism to calculate photon-spinor scattering, including the related particle-antiparticle annihilation amplitude. We start from a three-body system in which…

High Energy Physics - Theory · Physics 2007-05-23 James Lindesay , H. Pierre Noyes

We compute the two-loop massless QCD corrections to the helicity amplitudes for the production of two massive vector bosons in quark-antiquark annihilation, allowing for an arbitrary virtuality of the vector bosons: $q \bar q' \to V_1V_2$.…

High Energy Physics - Phenomenology · Physics 2015-10-28 Thomas Gehrmann , Andreas von Manteuffel , Lorenzo Tancredi