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Related papers: Infrared singularities in one-loop amplitudes

200 papers

We review the state-of-the-art knowledge of IR singularities in multileg QCD amplitudes, identifying the key reasons for the remarkable simplicity of the soft anomalous dimension. We then present a novel strategy to compute this quantity…

High Energy Physics - Phenomenology · Physics 2026-04-22 Einan Gardi , Zehao Zhu

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 present a method to numerically evaluate infrared-finite one- and two-loop integrals within the Four-Dimensional Regularization/Renormalization approach, in which a small mass serves as regulator. Typical integrals exhibit a logarithmic…

High Energy Physics - Phenomenology · Physics 2016-02-08 Tom Zirke

In this report, we present a discussion about different frameworks to perform precise higher-order computations for high-energy physics. These approaches implement novel strategies to deal with infrared and ultraviolet singularities in…

The soft anomalous dimension governs the infrared singularities of scattering amplitudes to all orders in perturbative quantum field theory, and is a crucial ingredient in both formal and phenomenological applications of non-abelian gauge…

High Energy Physics - Phenomenology · Physics 2017-10-25 Øyvind Almelid , Claude Duhr , Einan Gardi , Andrew McLeod , Chris D. White

Infrared regularized versions of 4-D N=1 superstring ground states are constructed by curving the spacetime. A similar regularization can be performed in field theory. For the IR regularized string ground states we derive the exact one-loop…

High Energy Physics - Theory · Physics 2009-10-28 Elias Kiritsis , Costas Kounnas

We present a completely numerical method of calculating one-loop amplitudes. Our approach is built upon two different existing methods: the contour deformation and the extrapolation methods. Taking the best features of each of them, we…

High Energy Physics - Phenomenology · Physics 2017-02-01 Goran Duplancic , Bruno Klajn

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

We present a new method for computing multi-loop scattering amplitudes in Quantum Field Theory. It extends the Generalized Unitarity method by constraining not only the integrand of the amplitude but also its full integrated form. Our…

High Energy Physics - Theory · Physics 2025-12-18 Piotr Bargiela

In this talk we review the recent computation of the five- and six-gluon two-loop amplitudes in Yang-Mills theory using local integrands which make the infrared pole structure manifest. We make some remarks on the connection with BCJ…

High Energy Physics - Phenomenology · Physics 2016-07-04 Simon Badger , Gustav Mogull , Tiziano Peraro

We discuss the structure of infrared singularities in on-shell QCD amplitudes with massive partons and present a general factorization formula in the limit of small parton masses. The factorization formula gives rise to an all-order…

High Energy Physics - Phenomenology · Physics 2010-10-27 A. Mitov , S. Moch

The one-loop QCD heavy quark potential is computed to order v^2 in the color singlet and octet channels. Several errors in the previous literature are corrected. To be consistent with the velocity power counting, the full dependence on |p'…

High Energy Physics - Phenomenology · Physics 2014-11-17 Aneesh V. Manohar , Iain W. Stewart

We review techniques for more efficient computation of perturbative scattering amplitudes in gauge theory, in particular tree and one-loop multi-parton amplitudes in QCD. We emphasize the advantages of (1) using color and helicity…

High Energy Physics - Phenomenology · Physics 2008-02-03 L. Dixon

We propose a new approach that allows for the separate numerical calculation of the real and imaginary parts of finite loop integrals. We find that at one-loop the real part is given by the Loop-Tree Duality integral supplemented with…

High Energy Physics - Phenomenology · Physics 2022-02-01 Dario Kermanschah

The recently developed on-shell bootstrap for computing one-loop amplitudes in non-supersymmetric theories such as QCD combines the unitarity method with loop-level on-shell recursion. For generic helicity configurations, the recursion…

High Energy Physics - Phenomenology · Physics 2008-11-26 Carola F. Berger , Zvi Bern , Lance J. Dixon , Darren Forde , David A. Kosower

We review recent progress in D-dimensional integrand reduction algorithms for two loop amplitudes and give examples of their application to non-planar maximal cuts of the five-point all-plus helicity amplitude in QCD.

High Energy Physics - Phenomenology · Physics 2014-07-14 Simon Badger , Hjalte Frellesvig , Yang Zhang

We present a set of relations between one-loop integral coefficients for dimensionally regulated QCD amplitudes. Within dimensional regularization, the combined use of color-kinematics duality and integrand reduction yields the existence of…

High Energy Physics - Phenomenology · Physics 2016-05-25 Amedeo Primo , William J. Torres Bobadilla

We analyze and implement the Local Analytic Sector Subtraction (LASS) scheme for handling infrared singularities in next-to-next-to-leading order (NNLO) calculations in perturbative QCD. We examine the key aspects of the scheme including…

High Energy Physics - Phenomenology · Physics 2024-07-03 Bakar Chargeishvili , Giuseppe Bevilacqua , Adam Kardos , Sven-Olaf Moch , Zoltán Trócsányi

We describe a constructive procedure to separate overlapping infrared divergences in multi-loop integrals. Working with a parametric representation in D=4-2*epsilon dimensions, adequate subtractions lead to a Laurent series in epsilon,…

High Energy Physics - Phenomenology · Physics 2009-10-31 T. Binoth , G. Heinrich

We calculate the one-loop QCD corrections for the decay of an off-shell vector boson with vector couplings into two pairs of quarks of equal or unequal flavours keeping all orders in the number of colours. These matrix elements are relevant…

High Energy Physics - Phenomenology · Physics 2008-11-26 E. W. N. Glover , D. J. Miller