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Related papers: Towards Colour Flow Evolution at Two Loops

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Using Laplace transform techniques, we describe the evolution of the color dipole cross section, at the leading-order and next-to-leading order approximations, from the Bartels-Golec-Biernat-Kowalski model in a kinematical region of low…

High Energy Physics - Phenomenology · Physics 2024-10-01 G. R. Boroun

We perform a systematic and comprehensive analysis of sub-leading colour corrections in perturbative QCD processes involving multiple soft gluon emissions. This necessitates going beyond the standard parton shower paradigm in order to…

High Energy Physics - Phenomenology · Physics 2025-05-22 Jeffrey R. Forshaw , Simon Plätzer , Fernando Torre González

We present a new framework for computing resummed and matched distributions in processes with many hard QCD jets. The intricate color structure of soft gluon emission at large angles renders resummed calculations highly non-trivial in this…

High Energy Physics - Phenomenology · Physics 2015-02-19 Erik Gerwick , Stefan Hoeche , Simone Marzani , Steffen Schumann

We extend the resummation of dimensionally-regulated amplitudes to next-to-next-to-leading poles. This requires the calculation of two-loop anomalous dimension matrices for color mixing through soft gluon exchange. Remarkably, we find that…

High Energy Physics - Phenomenology · Physics 2009-04-06 S. Mert Aybat , Lance J. Dixon , George Sterman

The small-$x$ deep inelastic scattering in the saturation region is governed by the non-linear evolution of Wilson-line operators. In the leading logarithmic approximation it is given by the BK equation for the evolution of color dipoles.…

High Energy Physics - Phenomenology · Physics 2008-11-26 Ian Balitsky , Giovanni A. Chirilli

We address the problem of decomposing graphs in perturbative QCD into terms associated with particular regions. Motivated by asking how to incorporate next-to-leading order (NLO) QCD corrections in parton-shower algorithms, we require that:…

High Energy Physics - Phenomenology · Physics 2010-02-03 J. C. Collins , F. Hautmann

We present an algorithm to include the correlation between the production and decay planes of gluons in a parton-shower simulation. The technique is based on identifying the charge currents responsible for the creation and annihilation of…

High Energy Physics - Phenomenology · Physics 2026-03-17 Stefan Höche , Mareen Hoppe , Daniel Reichelt

Parton shower evolution is given by a renormalization group equation that reflects the infrared behavior of perturbative QCD including color and spin and including quantum interference. With added approximations, such an evolution equation…

High Energy Physics - Phenomenology · Physics 2026-05-13 Zoltan Nagy , Davison E. Soper

In this talk, we review recent developments towards the calculation of multi-loop scattering amplitudes. In particular, we discuss how the colour-kinematics duality can provide new integral relations at one-loop level via the Loop-Tree…

High Energy Physics - Phenomenology · Physics 2018-01-10 William J. Torres Bobadilla

A continuous sequence of infinitesimal unitary transformations is used to diagonalize the quantum sine-Gordon model for \beta^2\in(2\pi,\infty). This approach can be understood as an extension of perturbative scaling theory since it links…

Statistical Mechanics · Physics 2009-10-31 Stefan Kehrein

In this paper we develop the DGLAP evolution for the system of produced gluons in the process of diffractive production in DIS, directly from the evolution equation in Color Glass Condensate approach. We are able to describe the available…

High Energy Physics - Phenomenology · Physics 2018-09-26 Carlos Contreras , Eugene Levin , Rodrigo Meneses , Irina Potashnikova

We compute the spectrum of gluons emitted by a highly energetic quark inside a flowing QCD medium, focusing on the soft gluon limit at first order in the opacity expansion. Specifically, we derive the leading energy-suppressed corrections…

High Energy Physics - Phenomenology · Physics 2024-06-24 Matvey V. Kuzmin , Xoán Mayo López

We present numerical solutions of the $Q^2$ evolution equations at next-to-leading order (NLO) for unpolarized and polarized parton distributions, in both the flavor non-singlet and singlet channels. The numerical method is based on a…

High Energy Physics - Phenomenology · Physics 2009-10-28 T. Weigl , W. Melnitchouk

It is useful to describe a leading order parton shower as the solution of a linear equation that specifies how the state of the partons evolves. This description involves an essential approximation of a strong ordering of virtualities as…

High Energy Physics - Phenomenology · Physics 2008-05-29 Zoltan Nagy , Davison E. Soper

Results are presented for the medium-induced, soft coherent radiation spectrum for all $2\to 2$ partonic channels in QCD, at leading-order in $\alpha_s$ but beyond leading logarithmic accuracy. The general formula is valid in the full…

High Energy Physics - Phenomenology · Physics 2024-06-03 Greg Jackson , Stéphane Peigné , Kazuhiro Watanabe

We derive an evolution equation for the generating functional which accounts for processes for both gluon emission and recombination. In terms of color dipoles, the kernel of this equation describes evolution as a classical branching…

High Energy Physics - Phenomenology · Physics 2009-11-11 Eugene Levin , Michael Lublinsky

In the semiclassical approach, inclusive and diffractive quark and gluon distributions are expressed in terms of correlation functions of Wilson loops. Each Wilson loop integrates the colour field strength in the area between the…

High Energy Physics - Phenomenology · Physics 2010-03-25 W. Buchmuller , T. Gehrmann , A. Hebecker

Using rapidity evolution equations we study two-to-two gauge-theory scattering amplitudes in the Regge limit. We carry out explicit computations at next-to-next-to-leading logarithmic accuracy through four loops and present new results for…

High Energy Physics - Phenomenology · Physics 2022-03-30 Giulio Falcioni , Einan Gardi , Niamh Maher , Calum Milloy , Leonardo Vernazza

We consider the interaction of the partonic fluctuation of a scalar ``photon'' with an external color field to calculate the leading and next-to-leading order gluon distribution of the proton following the work done by…

High Energy Physics - Phenomenology · Physics 2009-11-10 H. -J. Pirner , A. I. Shoshi , G. Soyez

We obtain an exact result for the soft gluon production and its p_T distribution due to a gluon loop in a constant chromo-electric background field E^a with arbitrary color. Unlike Schwinger's result for e^+e^- pair production in QED which…

High Energy Physics - Phenomenology · Physics 2009-11-11 Gouranga C. Nayak , Peter van Nieuwenhuizen