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Related papers: Two-loop helicity amplitudes for fermion-fermion s…

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We study the factorisation properties of one-loop scattering amplitudes in the triple collinear limit and extract the universal splitting amplitudes for processes initiated by a gluon. The splitting amplitudes are derived from the analytic…

High Energy Physics - Phenomenology · Physics 2015-07-20 Simon Badger , Francesco Buciuni , Tiziano Peraro

Supersymmetric integrands for the two-loop five-point amplitudes in ten-dimensional super Yang--Mills and type II supergravity are proposed. The kinematic numerators are manifestly local and satisfy the duality between color and kinematics…

High Energy Physics - Theory · Physics 2015-11-05 Carlos R. Mafra , Oliver Schlotterer

We compute the leading probability for a gluon to flip helicity state upon traversing a background plane wave gauge field in pure Yang-Mills theory and QCD, with an arbitrary number of colours and flavours. This is a one-loop calculation in…

High Energy Physics - Theory · Physics 2019-06-26 Tim Adamo , Anton Ilderton

We develop a spinor helicity formalism for five-dimensional scattering amplitudes of any mass and spin configuration. While five-dimensional spinor helicity variables have been previously studied in the context of N=2,4 supersymmetric…

High Energy Physics - Theory · Physics 2024-05-16 Andrzej Pokraka , Smita Rajan , Lecheng Ren , Anastasia Volovich , W. Wayne Zhao

We propose new formulae for the two-loop n-point D-dimensional integrands of scattering amplitudes in Yang-Mills theory and gravity. The loop integrands are written as a double-forward limit of tree-level trivalent diagrams, and are…

High Energy Physics - Theory · Physics 2020-01-29 Yvonne Geyer , Ricardo Monteiro , Ricardo Stark-Muchão

In view of the forthcoming High-Luminosity phase of the LHC, next-to-next-to-next-to-leading (N$^3$LO) calculations for the most phenomenologically relevant processes become necessary. In this work, we take the first step towards this goal…

High Energy Physics - Phenomenology · Physics 2023-12-07 Thomas Gehrmann , Petr Jakubčík , Cesare Carlo Mella , Nikolaos Syrrakos , Lorenzo Tancredi

A central problem in quantum field theory is the computation of scattering amplitudes. However, traditional methods are impractical to calculate high order phenomenologically relevant observables. Building on a few decades of astonishing…

High Energy Physics - Theory · Physics 2017-06-28 Livia Ferro , Tomasz Lukowski , Andrea Orta , Matteo Parisi

This paper studies various properties of amplitudes in 3d super Yang Mills theory. First we explain how to obtain the amplitudes of 3d super Yang Mills theories from 4d super Yang Mills theories and obtain their helicity structure. Next, we…

High Energy Physics - Theory · Physics 2015-06-05 Arthur E. Lipstein , Lionel Mason

We calculate one loop scattering amplitudes for arbitrary number of positive helicity on-shell gluons and one off-shell gluon treated within the quasi-multi Regge kinematics. The result is fully gauge invariant and possesses the correct…

High Energy Physics - Phenomenology · Physics 2021-03-05 Etienne Blanco , Andreas van Hameren , Piotr Kotko , Krzysztof Kutak

A conjecture made by Bern, Dixon, Dunbar, and Kosower asserts a simple dimension-shifting relationship between the one-loop structure of N = 4 MHV amplitudes and all-plus helicity amplitudes in pure Yang-Mills theory. We prove this…

High Energy Physics - Theory · Physics 2021-05-19 Ruth Britto , Guy R. Jehu , Andrea Orta

We asses a role of the double helicity-flip amplitudes in small-angle elastic pp-scattering and obtain a new unitary bound for the double helicity-flip amplitude F_2 in elastic pp-scattering at small values of t on the basis of the U-matrix…

High Energy Physics - Phenomenology · Physics 2015-06-25 S. M. Troshin , N. E. Tyurin

When scattering amplitudes are calculated in the double-logarithmic approximation, it is possible to relate the double-logarithmic on-shell and off-shell amplitudes. Explicit relations are obtained for scattering amplitudes in QED, QCD, and…

High Energy Physics - Phenomenology · Physics 2008-11-26 B. I. Ermolaev , M. Greco , F. Olness , S. I. Troyan

We present the universal two-loop splitting functions that describe the limits of two-loop $n$-point amplitudes of massless particles when two of the momenta are collinear. To derive the splitting amplitudes, we take the collinear limits of…

High Energy Physics - Phenomenology · Physics 2009-11-10 S. D. Badger , E. W. N. Glover

We review recent progress on computing scattering amplitudes of planar N=4 super Yang-Mills at strong coupling by using the AdS/CFT duality. We do explicit computations by using both, dimensional regularization and a cut-off in the radial…

High Energy Physics - Theory · Physics 2008-11-26 Luis F. Alday

I present results for the resummation of soft and collinear gluon contributions to QCD hard-scattering cross sections at two loops. This requires the calculation of UV and IR divergences through two loops and the construction of soft…

High Energy Physics - Phenomenology · Physics 2010-11-19 Nikolaos Kidonakis

Recently, an extension of the BCFW on-shell recursion relation suitable to compute gauge invariant scattering amplitudes with off-shell particles has been presented for Yang-Mills theories with fermions. In particular, 4- and 5-point…

High Energy Physics - Phenomenology · Physics 2015-10-28 Mirko Serino

We introduce a formalism for describing four-dimensional scattering amplitudes for particles of any mass and spin. This naturally extends the familiar spinor-helicity formalism for massless particles to one where these variables carry an…

High Energy Physics - Theory · Physics 2021-11-02 Nima Arkani-Hamed , Tzu-Chen Huang , Yu-tin Huang

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

Scattering amplitudes in $D$ dimensions involve particular terms that originate from the interplay of UV poles with the $D-4$ dimensional parts of loop numerators. Such contributions can be controlled through a finite set of…

High Energy Physics - Phenomenology · Physics 2020-10-28 Jean-Nicolas Lang , Stefano Pozzorini , Hantian Zhang , Max F. Zoller

We present an explicit expression for a particular $n$-gluon two loop scattering partial amplitude. Specifically we present an analytic form for the single trace $N_c$ independent colour partial amplitude for the case where all external…

High Energy Physics - Phenomenology · Physics 2020-04-08 David C. Dunbar , Warren B. Perkins , Joseph M. W. Strong