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Related papers: Simplifying Multi-Jet QCD Computation

200 papers

Ratios of multiplicity moments, H_q (cumulant over factorial moments K_q/F_q), have been observed to show an oscillatory behaviour with respect to order, q. Recent studies of e^+e^- annihilations at LEP have shown, moreover, that the…

High Energy Physics - Phenomenology · Physics 2011-07-19 Matthew A. Buican , Clemens F"orster , Wolfgang Ochs

We present cross sections and differential distributions for QCD radiative corrections to the QCD processes pp -> W+2j and pp -> Z+2j at the CERN LHC. Calculations are performed with the Monte Carlo program MCFM. Cross section dependence on…

High Energy Physics - Phenomenology · Physics 2008-11-26 John Campbell , R. K. Ellis , D. Rainwater

We present examples of on-shell recurrence relations for determining rational functions appearing in one-loop QCD amplitudes. In particular, we give relations for one-loop QCD amplitudes with all legs of positive helicity, or with one leg…

High Energy Physics - Theory · Physics 2010-11-15 Zvi Bern , Lance J. Dixon , David A. Kosower

The complete next-to-next-to leading order (NNLO) QCD correction matched with next-to-next-to leading logarithm (NNLL) has been studied for Drell-Yan production through spin-2 particle at the Large hadron collider (LHC). We consider generic…

High Energy Physics - Phenomenology · Physics 2021-04-28 Goutam Das , M. C. Kumar , Kajal Samanta

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

These lectures describe some of the latest data on particle production in high-energy collisions and compare them with theoretical calculations and models based on QCD. The main topics covered are: fragmentation functions and factorization,…

High Energy Physics - Phenomenology · Physics 2007-05-23 B. R. Webber

These lectures were presented at the 2024 QCD Masterclass in Saint-Jacut-de-la-Mer, France. They introduce and review fundamental theorems and principles of machine learning within the context of collider particle physics, focused on…

High Energy Physics - Phenomenology · Physics 2024-09-06 Andrew J. Larkoski

Heavy quark production in multijet events at $e^+e^-$ colliders is studied at tree level. Total production rates are given and compared with the corresponding results for massless quarks. A new method of computing helicity amplitudes is…

High Energy Physics - Phenomenology · Physics 2009-09-25 Alessandro Ballestrero , Ezio Maina , Stefano Moretti

After a brief historical review of the emergence of QCD as the quantum field theory of strong interactions, the basic notions of colour and gauge invariance are introduced leading to the QCD Lagrangian. The second lecture is devoted to…

High Energy Physics - Phenomenology · Physics 2007-05-23 Gerhard Ecker

We develop an approach for calculating heavy quark effective theory (HQET) light-cone distribution amplitudes (LCDAs) by employing a sequential effective theory methodology. The theoretical foundation of the framework is established,…

High Energy Physics - Lattice · Physics 2025-02-12 Xue-Ying Han , Jun Hua , Xiangdong Ji , Cai-Dian Lü , Andreas Schäfer , Yushan Su , Wei Wang , Ji Xu , Yibo Yang , Jian-Hui Zhang , Qi-An Zhang , Shuai Zhao

Many state-of-the-art QCD calculations for multileg processes use helicity amplitudes as their fundamental ingredients. We construct a simple and easy-to-use helicity operator basis in soft-collinear effective theory (SCET), for which the…

High Energy Physics - Phenomenology · Physics 2016-05-11 Ian Moult , Iain W. Stewart , Frank J. Tackmann , Wouter J. Waalewijn

I present generalized formulas for approximate corrections to QCD hard-scattering cross sections through second order in the perturbative expansion. The approximate results are based on recent two-loop calculations for soft and collinear…

High Energy Physics - Phenomenology · Physics 2011-09-09 Nikolaos Kidonakis

Experiments at the LHC are collecting a wealth of data with an unprecedented level of precision. As a consequence, the theoretical error is now starting to lag behind the experimental one, and a ceaseless effort is required to reduce the…

High Energy Physics - Phenomenology · Physics 2018-10-22 Luca Rottoli

We consider on-shell recursion relations for all Born QCD amplitudes. This includes amplitudes with several pairs of quarks and massive quarks. We give a detailed description on how to shift the external particles in spinor space and…

High Energy Physics - Phenomenology · Physics 2010-10-27 Christian Schwinn , Stefan Weinzierl

We discuss results from a recently proposed all-order description of hard, radiative corrections to certain multi-jet processes at hadron colliders. The description is based on obtaining an all-order estimate of the t-channel singularities…

High Energy Physics - Phenomenology · Physics 2010-01-26 Jeppe R. Andersen , Jennifer M. Smillie

Lecture notes on Poincar\'e-invariant scattering amplitudes and tree-level recursion relations in spinor-helicity formalism. We illustrate the non-perturbative constraints imposed over on-shell amplitudes by the Lorentz Little Group, and…

High Energy Physics - Theory · Physics 2017-05-30 Andrea Marzolla

We study all tree-level split helicity gluon amplitudes by using the recently proposed BCFW recursion relation and Hodges diagrams in ambitwistor space. We pick out the contributing diagrams and find that all of them can be divided into…

High Energy Physics - Theory · Physics 2010-01-07 Bin Chen , Jun-Bao Wu

Tree amplitudes of any gauge theory and gravity can be factorized into primitive three-particle amplitudes by the BCFW recursion relations. We show that the amplitudes at any perturbation order are given by tree amplitudes with additional…

High Energy Physics - Theory · Physics 2021-12-13 Markos Maniatis

This talk at Fradkin conference is devoted to brief description of latest results in two topics I worked on during last years. The multiresolution analysis and fast wavelet transform became a standard procedure for pattern recognition and I…

High Energy Physics - Phenomenology · Physics 2007-05-23 I. M. Dremin

We review some of the modern approaches to scattering amplitude computations in QCD and their application to precision LHC phenomenology. We emphasise the usefulness of momentum twistor variables in parameterising general amplitudes.

High Energy Physics - Phenomenology · Physics 2016-12-21 Simon Badger