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Related papers: Calculating Four-Loop Corrections in QCD

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Recently, we have introduced a unified theory to deal with perturbative and non-perturbative QCD contributions to hadronic structure functions in deep inelastic scattering. This formulation is realized by combining the coordinate space…

High Energy Physics - Phenomenology · Physics 2016-08-25 A. Harindranath , Rajen Kundu , Wei-Min Zhang

An overview is presented on the current status of main mathematical computation methods for the multi-loop corrections to single scale observables in quantum field theory and the associated mathematical number and function spaces and…

High Energy Physics - Phenomenology · Physics 2018-09-19 Johannes Blümlein , Carsten Schneider

The lectures are a practical introduction to perturbative calculations in QED and QCD. I discuss methods of calculation of one- and two-loop diagrams in dimensional regularization, MSbar and on-shell renormalization schemes, decoupling of…

High Energy Physics - Phenomenology · Physics 2007-05-23 Andrey Grozin

We present the O(alpha_s^4) virtual QCD corrections to gluon-gluon scattering due to the interference of tree and two-loop amplitudes. We work in conventional dimensional regularisation and give analytic expressions renormalised in the…

High Energy Physics - Phenomenology · Physics 2010-04-06 E. W. N. Glover , C. Oleari , M. E. Tejeda-Yeomans

A summary of the current understanding of methods of analytical higher order perturbative computations of total cross sections and decay widths in Quantum Chromodynamics is presented. As examples, the total cross section in electron…

High Energy Physics - Phenomenology · Physics 2009-10-28 Levan R. Surguladze , Mark A. Samuel

We compute squared matrix elements at next-to-next-to-leading order in perturbative quantum chromodynamics for the production of two or three (on- or off-shell) photons mediated via (light or heavy) quark loops. Our method handles all cases…

High Energy Physics - Phenomenology · Physics 2025-10-22 Dario Kermanschah , Matilde Vicini

We calculate four-loop QCD corrections to the electroweak $\rho$ parameter with a non-vanishing $b$ quark mass. At three loops, it was observed that elliptic integrals contribute to this observable. This prompts the question of which…

High Energy Physics - Phenomenology · Physics 2024-08-01 Samuel Abreu , Arnd Behring , Andrew McLeod , Ben Page

We present analytic results that describe fully-differential NNLO QCD corrections to deep-inelastic scattering processes within the nested soft-collinear subtraction scheme. This is the last building block required for the application of…

High Energy Physics - Phenomenology · Physics 2020-01-29 Konstantin Asteriadis , Fabrizio Caola , Kirill Melnikov , Raoul Röntsch

We present an analytical calculation of the two-loop QCD corrections to the electromagnetic form factor of heavy quarks. The two-loop contributions to the form factor are reduced to linear combinations of master integrals, which are…

High Energy Physics - Phenomenology · Physics 2009-07-29 J. Gluza , A. Mitov , S. Moch , T. Riemann

The status of the calculation of next-to-leading-order QCD corrections to hadronic final states in deeply inelastic scattering is reviewed, and an overview of the phenomenology (including the measurement of the strong coupling constant and…

High Energy Physics - Phenomenology · Physics 2007-05-23 Dirk Graudenz

The inclusive four-particle phase space integral of any $1\to 4$ matrix element in massless QCD contains divergences due to the soft and collinear emission of up to two particles in the final state. We show that any term appearing in this…

High Energy Physics - Phenomenology · Physics 2008-11-26 A. Gehrmann-De Ridder , T. Gehrmann , G. Heinrich

A review is presented on all higher order QCD corrections to deep inelastic structure functions. The implications of these corrections for polarized and unpolarized deep inelastic lepton-hadron scattering will be discussed.

High Energy Physics - Phenomenology · Physics 2007-05-23 W. L. van Neerven

We present a semi-numerical algorithm to calculate one-loop virtual corrections to scattering amplitudes. The divergences of the loop amplitudes are regulated using dimensional regularization. We treat in detail the case of amplitudes with…

High Energy Physics - Phenomenology · Physics 2008-11-26 R. K. Ellis , W. T. Giele , G. Zanderighi

We present a general subtraction method for computing radiative corrections to QCD jet cross sections at next-to-next-to-leading order accuracy. The steps needed to set up this subtraction scheme are the same as those used in…

High Energy Physics - Phenomenology · Physics 2009-11-13 Zoltan Trocsanyi , Gabor Somogyi

We perform the analysis of the existing inclusive deep inelastic scattering (DIS) data within NNLO QCD approximation. The parton distributions functions (PDFs) and the value of strong coupling constant $\alpha_{s}(M_Z)=0.1143\pm0.0013…

High Energy Physics - Phenomenology · Physics 2015-06-25 Alekhin Sergey

Two-loop electroweak corrections to polarized Moller scattering are studied in two different schemes at low energies. We find the finite $Q^2$ corrections to be well under control. The hadronic and perturbative QCD corrections to the…

High Energy Physics - Phenomenology · Physics 2022-07-14 Jens Erler , Rodolfo Ferro-Hernández , Ayres Freitas

We present calculations of next-to-leading order and resummed QCD corrections for semi-inclusive deep-inelastic scattering and single-inclusive e+e- annihilation. The resummation is performed to next-to-leading logarithmic accuracy. Knowing…

High Energy Physics - Phenomenology · Physics 2022-03-02 Daniele P. Anderle , Felix Ringer , Werner Vogelsang

The gradient flow in QCD is treated perturbatively through next-to-next-to-leading order in the strong coupling constant. The evaluation of the relevant momentum and flow-time integrals is described, including various means of validation.…

High Energy Physics - Phenomenology · Physics 2016-07-20 Robert V. Harlander , Tobias Neumann

In this paper we present a numerical implementation of the one-loop QED corrections to the hard-bremsstrahlung process e- e+ \to e- e+ gamma. These corrections can be included in the Monte Carlo event generators employed for simulating…

High Energy Physics - Phenomenology · Physics 2009-12-22 Stefano Actis , Pierpaolo Mastrolia , Giovanni Ossola

We present the O(alphas^4) virtual QCD corrections to gluon-gluon scattering due to the self-interference of the one-loop amplitude. We give analytic expressions renormalised in the MSbar scheme and work in conventional dimensional…

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