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Related papers: Two-loop splitting functions in QCD

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We review the current state-of-the-art in integrand level reduction for five-point scattering amplitudes at two loops in QCD. We present some benchmark results for the evaluation of the leading colour two-loop five-gluon amplitudes in the…

One loop corrections to the helicity amplitudes of all 2 -> 2 subprocesses are calculated in QCD and in N=1 supersymmetric Yang-Mills theory using two versions of dimensional regularization: the `t~Hooft-Veltman scheme and dimensional…

High Energy Physics - Phenomenology · Physics 2009-10-22 Zoltan Kunszt , Adrian Signer , Zoltán Trócsányi

We present the two-loop QCD corrections to the amplitude of the Higgs production associated with a $Z$ boson via the bottom quark-antiquark annihilation channel with a non-vanishing bottom-quark Yukawa coupling. The computation is performed…

High Energy Physics - Phenomenology · Physics 2019-12-16 Taushif Ahmed , A. H. Ajjath , Long Chen , Prasanna K. Dhani , Pooja Mukherjee , V. Ravindran

The high-energy factorization of gauge theory scattering amplitudes in terms of universal impact factors and a Reggeized exchange in the $t$-channel, corresponding to a Regge pole in the angular momentum plane, is know to conflict with the…

High Energy Physics - Phenomenology · Physics 2013-12-19 Vittorio Del Duca , Giulio Falcioni , Lorenzo Magnea , Leonardo Vernazza

We present a precise and efficient computation of the two-loop amplitudes entering the Higgs boson pair production process via gluon fusion. Our approach is based on the small-Higgs-mass expansion while keeping the full dependence on the…

High Energy Physics - Phenomenology · Physics 2021-09-29 Guoxing Wang , Yuxuan Wang , Xiaofeng Xu , Yongqi Xu , Li Lin Yang

We describe the application of a novel approach for the reduction of scattering amplitudes, based on multivariate polynomial division, which we have recently presented. This technique yields the complete integrand decomposition for…

High Energy Physics - Phenomenology · Physics 2013-07-17 Pierpaolo Mastrolia , Edoardo Mirabella , Giovanni Ossola , Tiziano Peraro

We present the two-loop leading colour QCD helicity amplitudes for the process $pp\to W(\to l\nu)\gamma+j$. We implement a complete reduction of the amplitudes, including the leptonic decay of the $W$-boson, using finite field arithmetic,…

High Energy Physics - Phenomenology · Physics 2022-05-25 Simon Badger , Heribertus Bayu Hartanto , Jakub Kryś , Simone Zoia

Processes involving electroweak vector bosons in association with jets are crucial for precision studies of the Standard Model at the Large Hadron Collider. Accurate predictions for the process $pp\rightarrow V(\rightarrow\bar\ell\ell)jj$…

High Energy Physics - Phenomenology · Physics 2024-09-25 Giuseppe De Laurentis

We present a symbol-level bootstrap construction of the planar, two-loop six-gluon scattering amplitude for the --++++ helicity configuration in QCD, focusing on the maximal weight pieces-the "most complicated terms" in the sense of Lipatov…

High Energy Physics - Theory · Physics 2026-03-24 Sérgio Carrôlo , Dmitry Chicherin , Johannes Henn , Qinglin Yang , Yang Zhang

Many search strategies for the Standard Model Higgs boson apply specific selection criteria on hadronic jets observed in association with the Higgs boson decay products, either in the form of a jet veto, or by defining event samples…

High Energy Physics - Phenomenology · Physics 2015-06-03 T. Gehrmann , M. Jaquier , E. W. N. Glover , A. Koukoutsakis

Double parton distributions (DPDs) receive a short-distance contribution from a single parton splitting to yield the two observed partons. We investigate this mechanism at next-to-leading order (NLO) in perturbation theory. Technically, we…

High Energy Physics - Phenomenology · Physics 2019-08-07 Markus Diehl , Jonathan R. Gaunt , Peter Ploessl , Andreas Schafer

We propose a first implementation of the integrand-reduction method for two-loop scattering amplitudes. We show that the residues of the amplitudes on multi-particle cuts are polynomials in the irreducible scalar products involving the loop…

High Energy Physics - Phenomenology · Physics 2015-05-30 Pierpaolo Mastrolia , Giovanni Ossola

In previous work, the two-loop five-point amplitudes in $\mathcal{N}=4$ super Yang-Mills theory and $\mathcal{N}=8$ supergravity were computed at symbol level. In this paper, we compute the full functional form. The amplitudes are assembled…

High Energy Physics - Theory · Physics 2020-12-02 Simon Caron-Huot , Dmitry Chicherin , Johannes Henn , Yang Zhang , 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 propose a new splitting behavior of tree-level string/particle amplitudes for scalars, gluons and gravitons. We identify certain subspaces in the space of Mandelstam variables, where the universal Koba-Nielsen factor splits into two…

High Energy Physics - Theory · Physics 2024-08-23 Qu Cao , Jin Dong , Song He , Canxin Shi

We present the analytic computation of all the planar master integrals which contribute to the two-loop scattering amplitudes for Higgs$\to 3$ partons, with full heavy-quark mass dependence. These are relevant for the NNLO corrections to…

High Energy Physics - Phenomenology · Physics 2017-02-01 Roberto Bonciani , Vittorio Del Duca , Hjalte Frellesvig , Johannes M. Henn , Francesco Moriello , Vladimir A. Smirnov

This thesis discusses how the pure spinor formalism can be used to efficiently compute superstring scattering amplitudes. We emphasize the pure spinor superspace form of the kinematic factors, where the simplifying features of this language…

High Energy Physics - Theory · Physics 2009-03-26 Carlos R. Mafra

We compute the integrand of the full-colour, two-loop, five-gluon scattering amplitude in pure Yang-Mills theory with all helicities positive, using generalized unitarity cuts. Tree-level BCJ relations, satisfied by amplitudes appearing in…

High Energy Physics - Phenomenology · Physics 2015-10-16 Simon Badger , Gustav Mogull , Alexander Ochirov , Donal O'Connell

We complete the computation of the two-loop helicity amplitudes for the production of three photons at hadron colliders, including all contributions beyond the leading-color approximation. We reconstruct the analytic form of the amplitudes…

High Energy Physics - Phenomenology · Physics 2023-10-16 Samuel Abreu , Giuseppe De Laurentis , Harald Ita , Maximillian Klinkert , Ben Page , Vasily Sotnikov

We update our approximate parametrizations of the three-loop splitting functions for the evolution of unpolarized parton densities in perturbative QCD. The new information taken into account is given by the additional Mellin moments…

High Energy Physics - Phenomenology · Physics 2008-11-26 W. L. van Neerven , A. Vogt