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Related papers: High-energy QCD amplitudes at two loops and beyond

200 papers

Splitting amplitudes are universal functions governing the collinear behavior of scattering amplitudes for massless particles. We compute the two-loop g -> gg splitting amplitudes in QCD, N=1, and N=4 super-Yang-Mills theories, which…

High Energy Physics - Phenomenology · Physics 2010-03-25 Zvi Bern , Lance J. Dixon , David A. Kosower

We consider the singular behaviour of one-loop QCD matrix elements when several external partons become simultaneously parallel. We present a new factorization formula that describes the singular collinear behaviour directly in colour…

High Energy Physics - Phenomenology · Physics 2010-04-05 Stefano Catani , Daniel de Florian , German Rodrigo

The infrared exponentiation properties of dimensionally-regularized multi-loop scattering amplitudes are typically hidden at the level of the integrand, materializing only after integral evaluation. We address this long-standing problem by…

High Energy Physics - Theory · Physics 2019-07-22 Robert M. Schabinger

We consider QCD corrections to two loops for the polarized amplitudes of $q{\bar q}\to Z +$ Higgs boson. First we show how the polarized amplitudes of $b \bar{b} \rightarrow Z h$ associated with a non-vanishing $b$-quark Yukawa coupling and…

High Energy Physics - Phenomenology · Physics 2020-08-26 Taushif Ahmed , Werner Bernreuther , Long Chen , Michal Czakon

We solve the integration-by-parts (IBP) identities needed for the computation of any planar two-loop five-point massless amplitude in QCD. We also derive some new results for the most complicated non-planar topology with irreducible…

High Energy Physics - Phenomenology · Physics 2019-08-13 Herschel A. Chawdhry , Matthew A. Lim , Alexander Mitov

We calculate higher-order quantum contributions in different Lorentz-violating parameters to the gauge sector of the extended QED. As a result of this one-loop calculation, some terms which do not produce first-order corrections, contribute…

High Energy Physics - Phenomenology · Physics 2018-08-21 A. P. Baeta Scarpelli , L. C. T. Brito , J. C. C. Felipe , J. R. Nascimento , A. Yu. Petrov

We compute for the first time the two-loop five-particle amplitude in $\mathcal{N}=8$ supergravity. Starting from the known integrand, we perform an integration-by-parts reduction and express the answer in terms of uniform weight master…

High Energy Physics - Theory · Physics 2019-05-01 D. Chicherin , T. Gehrmann , J. M. Henn , P. Wasser , Y. Zhang , S. Zoia

We compute the two-loop massless QCD corrections to the amplitude of Higgs boson decay to bottom quark pair and a gluon ($H \rightarrow b + \bar{b} + g$) in the higher powers of the dimensional regularization parameter $\epsilon$. The…

High Energy Physics - Phenomenology · Physics 2026-05-28 Pulak Banerjee , Chinmoy Dey , M. C. Kumar , Vaibhav Pandey , V. Ravindran

We present the two-loop pure gauge contribution to the gluon-gluon scattering amplitude with maximal helicity violation. Our construction of the amplitude does not rely directly on Feynman diagrams, but instead uses its analytic properties…

High Energy Physics - Phenomenology · Physics 2011-06-27 Z. Bern , L. Dixon , D. A. Kosower

With the aim to extend the study of inclusive heavy quarkonium production at forward rapidities with the resummation of high partonic center-of-momentum-energy logarithms beyond Leading Logarithmic Approximation (LLA), the explicit analytic…

High Energy Physics - Phenomenology · Physics 2024-10-25 Maxim Nefedov

We consider one-loop five-point QCD amplitudes in next-to-multi-Regge kinematics, and evaluate the one-loop impact factor for the emission of two gluons. This is the last ingredient which is necessary to evaluate the gluon-jet impact factor…

High Energy Physics - Phenomenology · Physics 2021-06-30 Marc Canay , Vittorio Del Duca

The quark form factor is known to exponentiate within the framework of dimensionally regularized perturbative QCD. The logarithm of the form factor is expressed in terms of integrals over the scale of the running coupling. I show that these…

High Energy Physics - Phenomenology · Physics 2009-10-31 Lorenzo Magnea

We compute all helicity amplitudes for the scattering of five partons in two-loop QCD in all the relevant flavor configurations, retaining all contributing color structures. We employ tensor projection to obtain helicity amplitudes in the…

High Energy Physics - Phenomenology · Physics 2023-12-01 Bakul Agarwal , Federico Buccioni , Federica Devoto , Giulio Gambuti , Andreas von Manteuffel , Lorenzo Tancredi

The removal of unphysical singularities in the perturbatively calculable part of the pion form factor--a classic example of a three-point function in QCD--is discussed. Different ``analytization'' procedures in the sense of Shirkov and…

High Energy Physics - Phenomenology · Physics 2007-05-23 A. P. Bakulev , A. I. Karanikas , N. G. Stefanis

We review the current status of high-multiplicity double-virtual QCD corrections to processes relevant for LHC phenomenology. In particular, we discuss the recent full-color calculation of the five-parton process, whose two-loop amplitudes…

High Energy Physics - Phenomenology · Physics 2024-06-27 Giuseppe De Laurentis

We represent the multi-leg tree-level amplitudes of quarks and gluons using a minimal set of lightcone variables, which incorporate all on-shell and momentum conservation conditions and naturally captures the separate longitudinal and…

High Energy Physics - Phenomenology · Physics 2025-06-13 Emmet P. Byrne , Vittorio Del Duca , Einan Gardi , Yuyu Mo , Jennifer M. Smillie

Using rapidity evolution equations we study two-to-two gauge-theory scattering amplitudes in the Regge limit. We carry out explicit computations at next-to-next-to-leading logarithmic accuracy through four loops and present new results for…

High Energy Physics - Phenomenology · Physics 2022-03-30 Giulio Falcioni , Einan Gardi , Niamh Maher , Calum Milloy , Leonardo Vernazza

This paper is a brief survey of the Balitskii-Fadin-Kuraev-Lipatov (BFKL) approach for the description of hard or semi-hard processes in the so-called Regge limit of perturbative QCD. The starting point is a fundamental property of…

High Energy Physics - Phenomenology · Physics 2007-05-23 Alessandro Papa

High-energy factorization in QCD is investigated beyond leading order and its relationship to the factorization theorem of mass singularities is established to any collinear accuracy. Flavour non-singlet observables are shown to be regular…

High Energy Physics - Phenomenology · Physics 2009-10-28 S. Catani , F. Hautmann

In this talk, we present the QCD factorization formula for heavy quarkonium production at large $p_T$ with factorized leading-power and next-to-leading power contributions in the $1/p_T$ expansion. We show that the leading order analytical…

High Energy Physics - Phenomenology · Physics 2015-11-27 Yan-Qing Ma , Jian-Wei Qiu , George Sterman , Hong Zhang