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Related papers: Automated computation of scattering amplitudes

200 papers

The analytic properties of the elastic hadron scattering amplitude are examined in the impact parameter representation at high energies. Different unitarization procedures and the corresponding non-linear equations are presented. Several…

High Energy Physics - Phenomenology · Physics 2008-11-26 O. V. Selyugin , J. R. Cudell

Scattering amplitudes computed at a fixed loop order, along with any other object computed in perturbative quantum field theory, can be expressed as a linear combination of a finite basis of loop integrals. To compute loop amplitudes in…

High Energy Physics - Phenomenology · Physics 2018-10-04 Alessandro Georgoudis , Kasper J. Larsen , Yang Zhang

The scattering equation formalism is a general framework for calculation of amplitudes in theories of massless particles. We provide a detailed introduction to the 4D scattering equation framework accessible to non-experts, outline current…

High Energy Physics - Theory · Physics 2018-08-29 Joseph A. Farrow

We present the complete automation of the computation of one-loop QCD corrections, including UV renormalization, to an arbitrary scattering process in the Standard Model. This is achieved by embedding the OPP integrand reduction technique,…

High Energy Physics - Phenomenology · Physics 2015-05-27 Valentin Hirschi , Rikkert Frederix , Stefano Frixione , Maria Vittoria Garzelli , Fabio Maltoni , Roberto Pittau

Based on the OPP technique and the HELAC framework, HELAC-1LOOP is a program that is capable of numerically evaluating QCD virtual corrections to scattering amplitudes. A detailed presentation of the algorithm is given, along with…

High Energy Physics - Phenomenology · Physics 2013-01-14 G. Bevilacqua , M. Czakon , M. V. Garzelli , A. van Hameren , A. Kardos , C. G. Papadopoulos , R. Pittau , M. Worek

We present the analytic and compact two-loop helicity amplitudes for QCD and QED corrections to the light-by-light scattering process with massive internal fermions. We express the master integrals either in terms of multiple polylogarithms…

High Energy Physics - Phenomenology · Physics 2024-03-22 Ajjath A H , Ekta Chaubey , Hua-Sheng Shao

We introduce a new technique to calculate perturbative corrections to neutron-deuteron ($nd$) scattering that does not require calculation of the full off-shell scattering amplitude. Its relation to the more familiar partial-resummation…

Nuclear Theory · Physics 2015-04-21 Jared Vanasse

We develop systematically to all orders the forward scattering description for retarded amplitudes in field theories at zero temperature. Subsequently, through the application of the thermal operator, we establish the forward scattering…

High Energy Physics - Theory · Physics 2008-11-26 Fernando T. Brandt , Ashok Das , Josif Frenkel , Silvana Perez

I review progress related to the calculation of QCD jet cross sections at the NLO accuracy. After a short introduction into the theory of NLO calculations, I discuss two recent developments: the calculation of two- and three-jet…

High Energy Physics - Phenomenology · Physics 2013-05-29 Zoltan Trocsanyi

I present a few new and recent ideas of the multiloop calculations.

High Energy Physics - Phenomenology · Physics 2014-05-23 Roman N. Lee

We relate scattering amplitudes in particle physics to maximum likelihood estimation for discrete models in algebraic statistics. The scattering potential plays the role of the log-likelihood function, and its critical points are solutions…

Algebraic Geometry · Mathematics 2021-12-15 Bernd Sturmfels , Simon Telen

In this article we present a number of developments within the scheme of Local Analytic Sector Subtraction for infrared divergences in QCD. First, we extend the scheme to deal with next-to-leading-order (NLO) singularities related to…

High Energy Physics - Phenomenology · Physics 2025-03-24 Gloria Bertolotti , Giovanni Limatola , Paolo Torrielli , Sandro Uccirati

We have calculated the one-loop scattering amplitude of an electron by an external Coulomb potential in QED free of infrared divergences. This feature is achieved by applying the Faddeev-Kulish formalism, which implies a redefinition of…

High Energy Physics - Phenomenology · Physics 2024-11-15 J. A. Oller , Marcela Peláez

Explicit formulas for the analytic extensions of the scattering matrix and the time delay of a quasi-one-dimensional discrete Schr\"odinger operator with a potential of finite support are derived. This includes a careful analysis of the…

Mathematical Physics · Physics 2021-01-25 Miguel Ballesteros , Gerardo Franco Córdova , Hermann Schulz-Baldes

We review recent progress in next-to-next-to-leading order (NNLO) perturbative QCD calculations with special emphasis on results ready for phenomenological applications. Important examples are new results on structure functions and jet or…

High Energy Physics - Phenomenology · Physics 2015-06-25 M. Klasen

We calculate field theory loop amplitudes by string methods, applied to half-maximal 4-point one-loop graviton amplitudes. Infrared divergences are regulated similarly to soft-collinear effective field theory (SCET): new mass scales are…

High Energy Physics - Theory · Physics 2026-03-31 Marcus Berg , Michael Haack , Yonatan Zimmerman

We describe the decomposition of one-loop QCD amplitudes in terms of colour-ordered building blocks. We give new expressions for the coefficients of QCD colour structures in terms of ordered objects called primitive amplitudes, for…

High Energy Physics - Phenomenology · Physics 2015-06-03 Harald Ita , Kemal Ozeren

The interpretation of experimental measurements at the LHC requires accurate theoretical predictions for exclusive observables, and in particular the summation of soft and collinear radiation to all orders in perturbation theory. We report…

High Energy Physics - Phenomenology · Physics 2015-02-13 Michael Czakon , Michael Krämer , Malgorzata Worek

We prove an integral formula for the spectral flow of differentiable loops of unitaries of the form ${\rm Id}+$Schatten. Our formula is in terms of a regularised winding number, expressed in terms of exact differential forms, and we show…

Functional Analysis · Mathematics 2026-04-27 A. Alexander , A. Carey , G. Levitina , A. Rennie

The analytic integration and simplification of multi-loop Feynman integrals to special functions and constants plays an important role to perform higher order perturbative calculations in the Standard Model of elementary particles. In this…

High Energy Physics - Theory · Physics 2023-01-11 Johannes Blümlein , Carsten Schneider