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Related papers: Automation of 2-loop Amplitude Calculations

200 papers

In this contribution we report on the calculation of the next-to-leading order (NLO) QCD corrections to the hadro-production of heavy neutral Higgs bosons and their decay into top-quark pairs within the type-II two-Higgs-doublet extension…

High Energy Physics - Phenomenology · Physics 2016-11-28 Werner Bernreuther , Peter Galler , Clemens Mellein , Zong-Guo Si , Peter Uwer

We improve the determination of the Higgs-boson mass in the MSSM with heavy superpartners, by computing the two-loop threshold corrections to the quartic Higgs coupling that involve both the strong and the electroweak gauge couplings.…

High Energy Physics - Phenomenology · Physics 2019-11-15 Emanuele Bagnaschi , Giuseppe Degrassi , Sebastian Paßehr , Pietro Slavich

We compute the two-loop massless QCD corrections to the helicity amplitudes for the production of two electroweak gauge bosons in the gluon fusion channel, $gg \to V_1 V_2$, keeping the virtuality of the vector bosons $V_1$ and $V_2$…

High Energy Physics - Phenomenology · Physics 2015-09-14 Andreas von Manteuffel , Lorenzo Tancredi

We present a method for the integrand-level reduction of two-loop helicity amplitudes in both $d=4-2\epsilon$ and $d=4$ dimensions. The amplitude is expressed in terms of a set of Feynman integrals and their coefficients that depend on the…

High Energy Physics - Phenomenology · Physics 2025-11-14 Giuseppe Bevilacqua , Dhimiter Canko , Costas Papadopoulos , Aris Spourdalakis

We describe techniques that simplify the calculation of one-loop QCD amplitudes with many external legs, which are needed for next-to-leading-order (NLO) corrections to multi-jet processes. The constraints imposed by perturbative unitarity,…

High Energy Physics - Phenomenology · Physics 2010-11-15 Z. Bern , L. Dixon , D. C. Dunbar , D. A. Kosower

NLO QCD corrections to H, W and Z production via vector boson fusion have recently been calculated in the form of flexible parton level Monte Carlo programs. This allows for the calculation of distributions and cross sections with cuts at…

High Energy Physics - Phenomenology · Physics 2009-11-10 T. Figy , C. Oleari , D. Zeppenfeld

We present results for the production of a pair of on-shell Z bosons via gluon fusion. This process occurs both through the production and decay of the Higgs boson, and through continuum production where the Z boson couples to a loop of…

High Energy Physics - Phenomenology · Physics 2016-08-09 John M. Campbell , R. Keith Ellis , Michal Czakon , Sebastian Kirchner

We compute the two-loop QCD corrections to amplitudes for processes $g g \to H g, q g \to H q$ and $q \bar{q} \to H g$ in the limit when the Higgs transverse momentum is larger than the top quark mass, $p_\perp \gg m_t$. These amplitudes…

High Energy Physics - Phenomenology · Physics 2018-04-04 Kirill Kudashkin , Kirill Melnikov , Christopher Wever

We compute the radiative corrections to the four-point amplitude $g+g \rightarrow A+A$ in massless Quantum Chromodynamics (QCD) up to order $a_s^4$ in perturbation theory. We used the effective field theory that describes the coupling of…

High Energy Physics - Phenomenology · Physics 2021-11-30 Arunima Bhattacharya , Maguni Mahakhud , Prakash Mathews , V. Ravindran

We consider Higgs boson production through gluon--gluon fusion in hadron collisions. We present a numerical program that computes the cross section up to NNLO in QCD perturbation theory. The program includes the decay modes H->gamma-gamma,…

High Energy Physics - Phenomenology · Physics 2008-11-26 S. Catani , M. Grazzini

We present a calculation of the NLO QCD corrections to the loop-induced production of a photon pair through gluon fusion, including massive top quarks at two loops. The two-loop virtual amplitudes are computed via projecting onto a set of…

High Energy Physics - Phenomenology · Physics 2019-12-13 Long Chen , Gudrun Heinrich , Stephan Jahn , Stephen P. Jones , Matthias Kerner , Johannes Schlenk , Hiroshi Yokoya

In this paper we compute the QCD corrections for the triple Higgs boson production cross section via gluon fusion, within the heavy-top approximation. We present, for the first time, analytical results for the next-to-leading order…

High Energy Physics - Phenomenology · Physics 2017-03-08 Daniel de Florian , Javier Mazzitelli

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

The two-loop QCD corrections to vector boson pair production at hadron colliders involve a new class of Feynman integrals: two-loop four-point functions with two off-shell external legs. We describe their reduction to a small set of master…

High Energy Physics - Phenomenology · Physics 2013-08-26 Thomas Gehrmann , Lorenzo Tancredi , Erich Weihs

We compute the 3-loop O(\alpha \alpha_s) correction to the Higgs boson production cross section arising from light quarks using an effective theory approach. Our calculation probes the factorization of QCD and electroweak perturbative…

High Energy Physics - Phenomenology · Physics 2010-01-15 Charalampos Anastasiou , Radja Boughezal , Frank Petriello

The most precise theoretical predictions for the total cross section for the associated production of a Higgs boson with a top-antitop quark pair at the LHC, first presented in \cite{Balsach:2025tth}, are reported. The calculation combines…

High Energy Physics - Phenomenology · Physics 2026-02-16 Anna Kulesza

We compute mixed QCD-weak corrections to inclusive Higgs production at the LHC from the partonic process $g g \rightarrow H q \bar{q}$. We start from the UV- and IR-finite one-loop weak amplitude and consider its interference with the…

High Energy Physics - Phenomenology · Physics 2019-05-22 Valentin Hirschi , Simone Lionetti , Armin Schweitzer

We present a calculation of the planar two-loop five-gluon amplitudes. The amplitudes are obtained in a variant of the generalized unitarity approach suitable for numerical computations, which we extend for use with finite field…

High Energy Physics - Phenomenology · Physics 2018-06-27 Samuel Abreu , Fernando Febres Cordero , Harald Ita , Ben Page , Mao Zeng

After reviewing the main features of the GoSam framework for automated one-loop calculations, we present a selection of recent phenomenological results obtained with it. In particular, we focus on the recent calculation of NLO QCD…

In this paper, we present analytical results for the two-loop QCD corrections to the production of two partons or a photon and a parton in hadronic collisions, mediated by loops of massive quarks. These amplitudes involve Feynman integrals…

High Energy Physics - Phenomenology · Physics 2025-09-22 Federico Coro , Christoph Nega , Lorenzo Tancredi , Fabian J. Wagner