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Related papers: Automation of one-loop QCD corrections

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This proceeding relates the recent developments of the MadLoop tool. MadLoop automates the computation of one-loop QCD corrections to an arbitrary scattering process in the Standard Model. I first review the current version of the code…

High Energy Physics - Phenomenology · Physics 2011-11-14 Valentin Hirschi

Heading towards a full automation of next-to-leading order (NLO) QCD corrections, one important ingredient is the analytical integration over the one-particle phase space of the unresolved particle that is necessary when adding the…

High Energy Physics - Phenomenology · Physics 2015-03-14 Rikkert Frederix , Thomas Gehrmann , Nicolas Greiner

We construct a specific formalism for calculating the one-loop virtual corrections for standard model processes with an arbitrary number of external legs. The procedure explicitly separates the infrared and ultraviolet divergences…

High Energy Physics - Phenomenology · Physics 2009-11-10 W. T. Giele , E. W. N. Glover

We compute the one-loop corrections to \tth up to order $\mathcal{O}(\epsilon^2)$ in the dimensional regularization parameter. We apply the projector method to compute polarized amplitudes, which generalize massless helicity amplitudes to…

High Energy Physics - Phenomenology · Physics 2023-12-18 Federico Buccioni , Philipp Alexander Kreer , Xiao Liu , Lorenzo Tancredi

With the advent of generalized unitarity and parametric integration techniques, the construction of a generic Next-to-Leading Order Monte Carlo becomes feasible. Such a generator will entail the treatment of QCD color in the amplitudes. We…

High Energy Physics - Phenomenology · Physics 2014-11-20 Walter Giele , Zoltan Kunszt , Jan Winter

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

We compute the ${\cal O}(\alpha_s^3)$ virtual QCD corrections to the $\gamma^*\to q\bar q g$ matrix element arising from the interference of the two-loop with the tree-level amplitude and from the self-interference of the one-loop…

High Energy Physics - Phenomenology · Physics 2010-04-06 L. W. Garland , T. Gehrmann , E. W. N. Glover , A. Koukoutsakis , E. Remiddi

In this work we revisit the algorithm of Denner and Pozzorini for the calculation of one-loop electroweak Sudakov logarithms and we automate it in the MadGraph5_aMC@NLO framework. We adapt the formulas for modern calculations, keeping…

High Energy Physics - Phenomenology · Physics 2022-04-21 Davide Pagani , Marco Zaro

We review progress in calculating one-loop scattering amplitudes required for next-to-leading-order corrections to QCD processes. The underlying technical developments include the spinor helicity formalism, color decompositions,…

High Energy Physics - Phenomenology · Physics 2010-11-15 Z. Bern , L. Dixon , D. A. Kosower

We present the implementation of the dipole subtraction formalism for the real radiation contributions to any next-to-leading order QCD process in the MadGraph/MadEvent framework. Both massless and massive dipoles are considered. Starting…

High Energy Physics - Phenomenology · Physics 2008-11-26 Rikkert Frederix , Thomas Gehrmann , Nicolas Greiner

In this paper we discuss techniques, which lead to a significant improvement of the efficiency of the Monte Carlo integration, when one-loop QCD amplitudes are calculated numerically with the help of the subtraction method and contour…

High Energy Physics - Phenomenology · Physics 2015-06-05 Sebastian Becker , Christian Reuschle , Stefan Weinzierl

We present a program that implements the OPP reduction method to extract the coefficients of the one-loop scalar integrals from a user defined (sub)-amplitude or Feynman Diagram, as well as the rational terms coming from the 4-dimensional…

High Energy Physics - Phenomenology · Physics 2011-05-05 Giovanni Ossola , Costas G. Papadopoulos , Roberto Pittau

In this contribution, we summarize the results from an NLO computation of the production of ttbb in hadronic collisions. The results are obtained by combining two programs: Helac-1Loop, based on the OPP method and the reduction code…

High Energy Physics - Phenomenology · Physics 2010-02-26 Malgorzata Worek

An algorithm, based on the OPP reduction method, to automatically compute any one-loop amplitude, for all momentum, color and helicity configurations of the external particles, is presented. It has been implemented using the tree-order…

High Energy Physics - Phenomenology · Physics 2010-11-19 A. van Hameren , C. G. Papadopoulos , R. Pittau

We propose an implementation of ZZ, ZZj and ZZjj productions in MadGraph5_aMC@NLO framework at $\sqrt{s}$ = 14 TeV. We calculate these processes at leading order and next-to-leading order with QCD corrections and we present a theoretical…

High Energy Physics - Phenomenology · Physics 2020-12-09 K. Djamaa , A. Mohamed-Meziani

We review some of the recent advances in the computation of one-loop scattering amplitudes which led to the construction of efficient and automated computational tools for NLO predictions. Particular attention is devoted to unitarity-based…

High Energy Physics - Phenomenology · Physics 2015-06-17 Giovanni Ossola

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

In this talk we discuss an algorithm for the numerical calculation of one-loop QCD amplitudes and present results at next-to-leading order for jet observables in electron-positron annihilation calculated with the above-mentioned method. The…

High Energy Physics - Phenomenology · Physics 2011-12-16 S. Becker , D. Goetz , C. Reuschle , C. Schwan , S. Weinzierl

We present an algorithm for the numerical calculation of one-loop QCD amplitudes. The algorithm consists of subtraction terms, approximating the soft, collinear and ultraviolet divergences of one-loop amplitudes and a method to deform the…

High Energy Physics - Phenomenology · Physics 2010-12-09 Sebastian Becker , Christian Reuschle , Stefan Weinzierl

We present an optimization of the reduction algorithm of one-loop amplitudes in terms of master integrals. It is based on the exploitation of the polynomial structure of the integrand when evaluated at values of the loop-momentum fulfilling…

High Energy Physics - Phenomenology · Physics 2008-11-26 P. Mastrolia , G. Ossola , C. G. Papadopoulos , R. Pittau
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