English
Related papers

Related papers: Three-loop helicity amplitudes for four-quark scat…

200 papers

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…

Recent Developments in computing very specific helicity amplitudes in two loop QCD are presented. The techniques focus upon the singular structure of the amplitude rather than on a diagramatic and integration approach

High Energy Physics - Phenomenology · Physics 2017-12-15 David C. Dunbar , John H Godwin , Guy R. Jehu , Warren B. Perkins

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 provide a complete and detailed study of the high-energy limit of four-parton scattering amplitudes in QCD, giving explicit results at two loops and higher orders, and going beyond next-to-leading logarithmic (NLL) accuracy. Building…

High Energy Physics - Phenomenology · Physics 2015-06-23 Vittorio Del Duca , Giulio Falcioni , Lorenzo Magnea , Leonardo Vernazza

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

We compute the contribution of three-loop mixed QCD-electroweak corrections ($\alpha_S^2\alpha^2$) to the $gg \to H$ scattering amplitude. We employ the method of differential equations to compute the relevant integrals and express them in…

High Energy Physics - Phenomenology · Physics 2018-05-10 Marco Bonetti , Kirill Melnikov , Lorenzo Tancredi

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

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 compute the three-loop four-gluon scattering amplitude in maximally supersymmetric Yang-Mills theory, including its full color dependence. Our result is the first complete computation of a non-planar four-particle scattering amplitude to…

High Energy Physics - Theory · Physics 2016-10-26 Johannes M. Henn , Bernhard Mistlberger

We link the FDR treatment of ultraviolet (UV) divergences to dimensional regularization up to two loops in QCD. This allows us to derive the one-loop and two-loop coupling constant and quark mass shifts necessary to translate infrared…

High Energy Physics - Phenomenology · Physics 2015-12-01 Ben Page , Roberto Pittau

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 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

We compute the ${\cal O}(\alpha_s^3)$ virtual QCD corrections to the $\gamma^*\to q\bar q g$ matrix element arising from the interference of the two-loop with the tree-level amplitude and from the self-interference of the one-loop…

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

We study two-loop corrections to the scattering amplitude of four massive leptons in quantum electrodynamics. These amplitudes involve previously unknown elliptic Feynman integrals, which we compute analytically using the differential…

High Energy Physics - Phenomenology · Physics 2023-11-14 Maximilian Delto , Claude Duhr , Lorenzo Tancredi , Yu Jiao Zhu

We present an analytic expression for the six-point all-plus helicity amplitude in QCD at two-loops. We compute the rational terms in a compact analytic form organised by their singularity structure.

High Energy Physics - Theory · Physics 2016-08-10 David C. Dunbar , Warren B. Perkins

We have calculated the complete matrix of three-loop helicity-difference (`polarized') splitting functions Delta P_ik^(2), i,k = q,g, in massless perturbative QCD. In this note we briefly discuss some properties of the polarized splitting…

High Energy Physics - Phenomenology · Physics 2014-05-15 A. Vogt , S. Moch , J. A. M. Vermaseren

We present analytic results for the one-loop corrections of the helicity amplitudes of the QCD five-parton subprocesses involving four quarks and one gluon obtained with a standard Feynman diagram calculation using dimensional reduction.

High Energy Physics - Phenomenology · Physics 2009-10-28 Zoltan Kunszt , Adrian Signer , Zoltan Trocsanyi

An exact formula is derived for the infrared singularities of dimensionally regularized scattering amplitudes in massless QCD with an arbitrary number of legs, valid at any number of loops. It is based on the conjecture that the…

High Energy Physics - Phenomenology · Physics 2013-10-23 Thomas Becher , Matthias Neubert

We perform a dedicated study of the $q \bar{q}$-initiated two-loop electroweak-QCD Drell-Yan scattering amplitude in dimensional regularization schemes for vanishing light quark and lepton masses. For the relative order $\alpha$ and…

High Energy Physics - Phenomenology · Physics 2023-01-11 Matthias Heller , Andreas von Manteuffel , Robert M. Schabinger , Hubert Spiesberger

We use lattice QCD calculations of the finite-volume spectra of systems of two and three mesons to determine, for the first time, three-particle scattering amplitudes with physical quark masses. Our results are for combinations of $\pi^+$…

‹ Prev 1 4 5 6 7 8 10 Next ›