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Related papers: Complete two-loop QCD amplitudes for $tW$ producti…

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We present the analytical results of the two-loop amplitudes for hadronic $tW$ production, focusing on the leading color and light fermion-loop contributions. The calculation of the two-loop integrals is performed using the method of…

High Energy Physics - Phenomenology · Physics 2022-12-14 Long-Bin Chen , Liang Dong , Hai Tao Li , Zhao Li , Jian Wang , Yefan Wang

We present the analytic form of the two-loop five-gluon scattering amplitudes in QCD for a complete set of independent helicity configurations of external gluons. These include the first analytic results for five-point two-loop amplitudes…

High Energy Physics - Phenomenology · Physics 2019-03-06 S. Abreu , J. Dormans , F. Febres Cordero , H. Ita , B. Page

We calculate the complete set of two-loop leading-colour QCD helicity amplitudes for $\gamma \gamma j$-production at hadron colliders. Our results are presented in a compact, fully-analytical form.

High Energy Physics - Phenomenology · Physics 2021-08-25 Herschel A. Chawdhry , Michal Czakon , Alexander Mitov , Rene Poncelet

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 compute the full set of two-loop Feynman integrals appearing in massless two-loop four-point functions with two off-shell legs with the same invariant mass. These integrals allow to determine the two-loop corrections to the amplitudes…

High Energy Physics - Phenomenology · Physics 2014-06-13 Thomas Gehrmann , Andreas von Manteuffel , Lorenzo Tancredi , Erich Weihs

The $tW$ associated production has the second-largest cross section among three single top production channels. A complete study of NNLO QCD corrections to $tW$ production is still missing in literature. We present the calculation of part…

High Energy Physics - Phenomenology · Physics 2021-11-30 Ming-Ming Long , Ren-You Zhang , Wen-Gan Ma , Yi Jiang , Liang Han , Zhe Li , Shuai-Shuai Wang

The factorisation of QCD matrix elements in the limit of two external partons becoming collinear is described by process-independent splitting amplitudes, which can be expanded systematically in perturbation theory. Working in conventional…

High Energy Physics - Phenomenology · Physics 2015-06-23 Claude Duhr , Thomas Gehrmann , Matthieu Jaquier

Virtual two-loop corrections to scattering amplitudes are a key ingredient to precision physics at collider experiments. We compute the full set of planar master integrals relevant to five-point functions in massless QCD, and use these to…

High Energy Physics - Phenomenology · Physics 2016-04-18 T. Gehrmann , J. M. Henn , N. A. Lo Presti

We compute the two-loop QCD corrections to $q g \to H q$ and $q \bar{q} \to H g$ amplitudes mediated by loops of nearly massless quarks. These amplitudes provide the last missing ingredient required to compute the NLO QCD corrections to the…

High Energy Physics - Phenomenology · Physics 2017-03-22 Kirill Melnikov , Lorenzo Tancredi , Christopher Wever

We compute two-loop helicity amplitudes in QCD for diphoton production through quark- and gluon-initiated channels, accounting for a massive internal quark loop by keeping its full mass dependence. Using physical projectors, we directly…

High Energy Physics - Phenomenology · Physics 2025-02-06 Taushif Ahmed , Amlan Chakraborty , Ekta Chaubey , Mandeep Kaur

We present the analytic and compact two-loop helicity amplitudes for QCD and QED corrections to the light-by-light scattering process with massive internal fermions. We express the master integrals either in terms of multiple polylogarithms…

High Energy Physics - Phenomenology · Physics 2024-03-22 Ajjath A H , Ekta Chaubey , Hua-Sheng Shao

We compute the two-loop QCD helicity amplitudes for the process e^+e^- --> q bar{q} g. The amplitudes are extracted in a scheme-independent manner from the coefficients appearing in the general tensorial structure for this process. The…

High Energy Physics - Phenomenology · Physics 2010-04-06 L. W. Garland , T. Gehrmann , E. W. N. Glover , A. Koukoutsakis , E. Remiddi

We derive the two-loop QCD helicity amplitudes for the processes $l q \to l qg$ ($l \bar q \to l \bar q g$) and $l g \to l q\bar q$, which are the partonic reactions yielding $(2+1)$-jet final states in deep inelastic lepton nucleon…

High Energy Physics - Phenomenology · Physics 2009-06-25 T. Gehrmann , E. W. N. Glover

We compute the planar part of the two-loop five gluon amplitude with all helicities positive. To perform the calculation we develop a D-dimensional generalized unitarity procedure allowing us to reconstruct the amplitude by cutting into…

High Energy Physics - Phenomenology · Physics 2015-07-21 Simon Badger , Hjalte Frellesvig , Yang Zhang

We compute helicity amplitudes for the one-loop QCD corrections to top-quark pair production analytically in terms of a set of uniformly transcendental master integrals. We provide corrections up to $O(\epsilon^2)$ in the dimensional…

High Energy Physics - Phenomenology · Physics 2022-06-29 Simon Badger , Matteo Becchetti , Ekta Chaubey , Robin Marzucca , Francesco Sarandrea

We present an analytical calculation of the two-loop QCD corrections to the electromagnetic form factor of heavy quarks. The two-loop contributions to the form factor are reduced to linear combinations of master integrals, which are…

High Energy Physics - Phenomenology · Physics 2009-07-29 J. Gluza , A. Mitov , S. Moch , T. Riemann

We compute the one-loop QCD amplitude for the process gg-->Q\bar{Q} in dimensional regularization through order \epsilon^2 in the dimensional regulator and for arbitrary quark mass values. This result is an ingredient of the NNLO…

High Energy Physics - Phenomenology · Physics 2008-12-30 Charalampos Anastasiou , S. Mert Aybat

We discuss recent progress towards extending the Helac framework to the calculation of two-loop amplitudes. A general algorithm for the automated computation of two-loop integrands is described. The algorithm covers all the steps of the…

High Energy Physics - Phenomenology · Physics 2024-01-19 Giuseppe Bevilacqua , Dhimiter Canko , Costas Papadopoulos

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 four-loop QCD corrections to the electroweak $\rho$-parameter arising from top and bottom quark loops are computed. Specifically we evaluate the missing ``non-singlet'' piece. Using algebraic methods the amplitude is reduced to a set of…

High Energy Physics - Phenomenology · Physics 2008-11-26 K. G. Chetyrkin , M. Faisst , J. H. Kühn , P. Maierhoefer , C. Sturm