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Related papers: Multiparton NLO corrections by numerical methods

200 papers

We present an alternative method to calculate cross sections for multi-parton scattering processes in the Standard Model at leading order. The helicity amplitudes are computed using recursion relations in the number of particles, based on…

High Energy Physics - Phenomenology · Physics 2008-11-26 Costas G. Papadopoulos , Malgorzata Worek

This article gives results on several jet algorithms in electron-positron annihilation: Considered are the exclusive sequential recombination algorithms Durham, Geneva, Jade-E0 and Cambridge, which are typically used in electron-positron…

High Energy Physics - Phenomenology · Physics 2015-03-17 Stefan Weinzierl

This paper describes a method of numerical evaluating high-order QED contributions to the electron anomalous magnetic moment. The method is based on subtraction of infrared and ultraviolet divergences in Feynman-parametric space before…

High Energy Physics - Phenomenology · Physics 2018-11-07 Sergey Volkov

We revisit the calculation of the average jet multiplicity in high-energy collisions. First, we introduce a new definition of (sub)jet multiplicity based on Lund declusterings obtained using the Cambridge jet algorithm. We develop a new…

High Energy Physics - Phenomenology · Physics 2022-11-09 Rok Medves , Alba Soto-Ontoso , Gregory Soyez

We compute the complete one-loop corrections to the simplest class of QCD gluon amplitudes, those with two color-adjacent opposite-helicity external particles. We present results for an arbitrary number of external legs. The computation…

High Energy Physics - Phenomenology · Physics 2009-11-11 Darren Forde , David A. Kosower

We compute the ${\cal O}(\alpha^2\alpha_s^2)$ perturbative corrections to inclusive jet production in electron-nucleon collisions. This process is of particular interest to the physics program of a future Electron Ion Collider (EIC). We…

High Energy Physics - Phenomenology · Physics 2016-10-28 Gabriel Abelof , Radja Boughezal , Xiaohui Liu , Frank Petriello

In this thesis, we present recent advances at the precision frontier of higher-order quantum chromodynamics (QCD) calculations. We consider massless two-loop five-point amplitudes, with a particular focus on diphoton-plus-jet production…

High Energy Physics - Phenomenology · Physics 2022-10-14 Ryan Moodie

One- and two-jet inclusive quantities in hadron collisions have already been calculated to next-to-leading order accuracy, using both the subtraction and the cone method. Since the one-loop corrections have recently been obtained for all…

High Energy Physics - Phenomenology · Physics 2009-10-28 S. Frixione , Z. Kunszt , A. Signer

The infrared exponentiation properties of dimensionally-regularized multi-loop scattering amplitudes are typically hidden at the level of the integrand, materializing only after integral evaluation. We address this long-standing problem by…

High Energy Physics - Theory · Physics 2019-07-22 Robert M. Schabinger

We report next-to-leading order perturbative QCD predictions of 4 jet event shape variables for the process e+e- \to 4 jets obtained using the general purpose Monte Carlo EERAD2. This program is based on the known `squared' one loop matrix…

High Energy Physics - Phenomenology · Physics 2008-11-26 J. M. Campbell , M. A. Cullen , E. W. N. Glover

The success of the experimental program at the Tevatron re-inforced the idea that precision physics at hadron colliders is desirable and, indeed, possible. The Tevatron data strongly suggests that one-loop computations in QCD describe hard…

High Energy Physics - Phenomenology · Physics 2015-05-28 R. Keith Ellis , Zoltan Kunszt , Kirill Melnikov , Giulia Zanderighi

The NNLO QCD corrections to the $e^+e^- \to 3$ jets can be decomposed according to their colour factors. Out of the seven colour factors, three are of QED-type: $1/N^2$, $N_F/N$ and $N_F^2$. We use the antenna subtraction method to compute…

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

We present a subtraction scheme for eliminating the ultraviolet, soft, and collinear divergences in the numerical calculation of an arbitrary one-loop QCD amplitude with an arbitrary number of external legs. The subtractions consist of…

High Energy Physics - Phenomenology · Physics 2009-11-10 Zoltan Nagy , Davison E. Soper

This report describes the recent efforts to compute analytic formulae for the Next-to-Leading-Order (NLO) QCD corrections to Higgs plus two jet production at hadron colliders. In these calculations the Higgs boson couples to gluons via a…

High Energy Physics - Phenomenology · Physics 2014-11-20 Ciaran Williams

We present an overview of techniques developed in recent years for the efficient calculation of one-loop multiparton amplitudes, in particular those relying on unitarity and collinear factorization.

High Energy Physics - Phenomenology · Physics 2009-10-30 Zvi Bern , Lance Dixon , David C. Dunbar , David A. Kosower

I will present a new method for thinking about and for computing loop integrals based on differential equations. All required information is obtained by algebraic means and is encoded in a small set of simple quantities that I will…

High Energy Physics - Phenomenology · Physics 2014-05-16 Johannes M. Henn

A way to efficiently compute helicity amplitudes for arbitrary tree-level scattering processes in QCD is presented. The scattering amplitude is evaluated recursively through a set of Dyson-Schwinger equations. The computational cost of this…

High Energy Physics - Phenomenology · Physics 2009-11-11 Costas G. Papadopoulos , Malgorzata Worek

Given a next-to-leading order calculation, we show how to set up a computer program, which generates a sequence of unweighted momentum configurations, each configuration containing either n or n+1 four-vectors, such that for any infrared…

High Energy Physics - Phenomenology · Physics 2009-11-07 Stefan Weinzierl

We describe a general method that enables us to obtain all the singular terms of helicity amplitudes of n-parton processes at one loop. The algorithm uses helicity amplitudes at tree level and simple color algebra. We illustrate the method…

High Energy Physics - Phenomenology · Physics 2009-10-28 Zoltan Kunszt , Adrian Signer , Zoltan Trocsanyi

In this talk we discuss recent progress concerning precise predictions for the LHC. We give a status report of an application of the GOLEM method to deal with multi-leg one-loop amplitudes, namely the next-to-leading order QCD corrections…

High Energy Physics - Phenomenology · Physics 2008-07-07 S. Karg , G. Sanguinetti