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Related papers: Antenna functions from MHV rules

200 papers

We show that the Mellin transform of an $n$-point tree level MHV gluon scattering amplitude, also known as the celestial amplitude in pure Yang-Mills theory, satisfies a system of $(n-2)$ linear first order partial differential equations…

High Energy Physics - Theory · Physics 2021-11-03 Shamik Banerjee , Sudip Ghosh

We study the infrared behaviour of tree-level QCD amplitudes and we derive infrared-factorization formulae that are valid at any perturbative order. We explicitly compute all the universal infrared factors that control the singularities in…

High Energy Physics - Phenomenology · Physics 2015-06-25 S. Catani , M. Grazzini

We compute the quark and gluon transverse momentum dependent parton distribution functions at next-to-next-to-next-to-leading order (N$^3$LO) in perturbative QCD. Our calculation is based on an expansion of the differential Higgs boson and…

High Energy Physics - Phenomenology · Physics 2020-10-28 Markus A. Ebert , Bernhard Mistlberger , Gherardo Vita

We evaluate all split helicity gluon tree amplitudes in open twistor string theory. We show that these amplitudes satisfy the BCFW recurrence relations restricted to the split helicity case and, hence, that these amplitudes agree with those…

High Energy Physics - Theory · Physics 2012-09-10 Louise Dolan , Peter Goddard

In the high-energy limit, we compute the gauge-invariant three-parton forward clusters, which in the BFKL theory constitute the tree parts of the NNLO impact factors. In the triple collinear limit, we obtain the polarized double-splitting…

High Energy Physics - Phenomenology · Physics 2008-11-26 Vittorio Del Duca , Alberto Frizzo , Fabio Maltoni

Hadron wave functions and form factors can be extracted using four-point correlators. Stochastic techniques are used to estimate the all to all propagators, which are required for the exact calculation of four-point functions. We apply the…

High Energy Physics - Lattice · Physics 2008-11-26 Constantia Alexandrou , Giannis Koutsou

We present the two-loop helicity amplitudes for the scattering of massless quarks and massless gauge bosons in QCD. We use projector techniques to compute the coefficients of the general tensor describing the two-quark two-boson amplitude…

High Energy Physics - Phenomenology · Physics 2010-02-03 E. W. N. Glover , M. E. Tejeda-Yeomans

In this paper we revisit the general phenomenon that scattering amplitudes of pions can be obtained from "dimensional reduction" of gluons in higher dimensions in a more general context. We show that such "dimensional reduction" operations…

High Energy Physics - Theory · Physics 2024-07-22 Jin Dong , Xiang Li , Fan Zhu

In this paper, we show that multiple maximally soft (anti-)quark and gluon emissions exponentiate at the level of either the amplitude or cross-section. We first show that such emissions can be captured by introducing new soft emission…

High Energy Physics - Phenomenology · Physics 2023-12-20 Melissa van Beekveld , Leonardo Vernazza , Chris D. White

In this paper, we study the newly discovered universal splitting behavior for tree-level scattering amplitudes of particles and strings~\cite{Cao:2024gln}: when a set of Mandelstam variables (and Lorentz products involving polarizations for…

High Energy Physics - Theory · Physics 2025-01-15 Qu Cao , Jin Dong , Song He , Canxin Shi , Fanky Zhu

The spectrum of coherent gluon radiation from a quark-anti-quark pair experiencing multiple scatterings within a coloured medium is central for understanding in-medium parton cascades. Despite its foundational importance, current results…

Studies of medium-induced QCD radiation usually rely on the calculation of single-gluon radiation spectrum off an energetic parton traversing an extended colored medium. Recently, the importance of interference effects between emitters in…

High Energy Physics - Phenomenology · Physics 2015-05-30 Néstor Armesto , Hao Ma , Yacine Mehtar-Tani , Carlos A. Salgado , Konrad Tywoniuk

We report on the extension of the data fitting considering the QCD inspired model based on the summation of gluon ladders applied to the $ep$ scattering. In lines of a two Pomeron approach, the structure function $F_2$ has a hard piece…

High Energy Physics - Phenomenology · Physics 2007-05-23 A. Lengyel , M. V. T. Machado

The rational parts of 6-gluon one-loop amplitudes with scalars circulating in the loop are computed by using the newly developed method for computing the rational parts directly from Feynman integrals. We present the analytic results for…

High Energy Physics - Phenomenology · Physics 2008-11-26 Zhi-Guang Xiao , Gang Yang , Chuan-Jie Zhu

On-shell kinematics for gluon scattering can be parametrized with points on the celestial sphere; in the limit where these points collide, it is known that tree-level gluon scattering amplitudes exhibit an operator product expansion…

High Energy Physics - Theory · Physics 2023-04-19 Tim Adamo , Wei Bu , Eduardo Casali , Atul Sharma

By analytically continuing QCD scattering amplitudes through specific complexified momenta, one can study and learn about the nature and the consequences of factorization and unitarity. In some cases, when coupled with the largest time…

High Energy Physics - Theory · Physics 2008-11-26 Diana Vaman , York-Peng Yao

We consider the process containing two quark lines and an arbitrary number of gluons in a spinor helicity framework. A current with two off-shell gluons appears in the amplitude. We first study this modified gluon current using recursion…

High Energy Physics - Phenomenology · Physics 2009-10-22 G. Mahlon , T. M. Yan , C. Dunn

Recently, spin-one wavefunctions in four dimensions that are conformal primaries of the Lorentz group SL(2,C) were constructed. We compute low-point, tree-level gluon scattering amplitudes in the space of these conformal primary…

High Energy Physics - Theory · Physics 2017-11-01 Sabrina Pasterski , Shu-Heng Shao , Andrew Strominger

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

We compute the two-loop helicity amplitudes for the scattering of five gluons, including all contributions beyond the leading-color approximation. The analytic expressions are represented as linear combinations of transcendental functions…

High Energy Physics - Phenomenology · Physics 2024-05-15 Giuseppe De Laurentis , Harald Ita , Maximillian Klinkert , Vasily Sotnikov