English
Related papers

Related papers: Angular ordering and small-x evolution

200 papers

We review the perturbative evolution of the polarized structure functions g_1 and their associated parton distribution functions, with particular emphasis on the anomalous coupling of the first moment of the polarized gluon distribution. We…

High Energy Physics - Phenomenology · Physics 2008-02-03 R. D. Ball

In this paper we derive an integral equation for the evolution of unintegrated (longitudinally) polarized quark and gluon parton distributions. The conventional CCFM framework is extended at small x in order to incorporate the QCD…

High Energy Physics - Phenomenology · Physics 2009-11-07 Jan Kwiecinski , Martin Maul

We study the evolution of the small $x$ gluon transverse momentum dependent(TMD) distribution in the dilute limit. The calculation has been carried out in the Ji-Ma-Yuan scheme using a simple quark target model. As expected, we find that…

High Energy Physics - Phenomenology · Physics 2016-07-20 Jian Zhou

I discuss how the rapidity evolution of gluon transverse momentum dependent distribution changes from nonlinear evolution at small $x\ll 1$ to linear evolution at moderate $x\sim 1$.

High Energy Physics - Phenomenology · Physics 2015-10-23 Ian Balitsky

We discuss perturbative evolution of the polarized structure function g_1 in the (x,Q^2) plane, with special regard to the small-x region. We determine g_1 in terms of polarized quark and gluon distributions using coefficient functions to…

High Energy Physics - Phenomenology · Physics 2009-10-28 R. D. Ball , S. Forte , G. Ridolfi

Using the colour dipole picture for photon-nucleus interactions at small $x$ together with the Color Glass Condensate (CGC) effective theory, we demonstrate that the next-to-leading (NLO) order corrections to the cross-section for the…

High Energy Physics - Phenomenology · Physics 2025-05-05 Paul Caucal , Edmond Iancu

We discuss the quantitative consequences of the resummation of the small-x contributions to the anomalous dimensions beyond next-to-leading order in alpha_s and up to next order in ln(1/x) (NLx) in a framework based on the renormalization…

High Energy Physics - Phenomenology · Physics 2007-05-23 J. Blümlein , V. Ravindran , W. L. van Neerven , A. Vogt

We numerically study the effects of high gluon density at small x on the evolution of gluon distribution function in both hadrons and nuclei. Using a newly derived, Wilson renormalization group-based evolution equation which includes n to 1…

High Energy Physics - Phenomenology · Physics 2014-11-17 Jamal Jalilian-Marian , Xin-Nian Wang

We revisit the problem of the small Bjorken-$x$ asymptotics of the quark and gluon orbital angular momentum (OAM) distributions in the proton utilizing the revised small-$x$ helicity evolution derived recently. We relate the quark and gluon…

High Energy Physics - Phenomenology · Physics 2024-07-24 Yuri V. Kovchegov , Brandon Manley

Color quadrupoles have been found to be important in the proper description of observables sensitive to the small-x regime in nuclei as well as in the operator definition of the Weizs\"acker-Williams gluon distribution. In this paper, we…

High Energy Physics - Phenomenology · Physics 2015-05-30 Fabio Dominguez , A. H. Mueller , Stéphane Munier , Bo-Wen Xiao

We recall the origin of angular ordering of soft parton emission in the region of small $x$ and show that this coherent structure can be detected in associated distributions. For structure functions at small $x$ and at fixed transverse…

High Energy Physics - Phenomenology · Physics 2009-10-28 Giuseppe Marchesini

The impact of the resummed next-to-leading logarithmic small-$x$ contributions to the anomalous dimension $\gamma_{gg}$ is evaluated for the unpolarized parton densities and structure functions of the nucleon. These new terms diminish the…

High Energy Physics - Phenomenology · Physics 2016-09-06 J. Blümlein , A. Vogt

The status of the resummation of small x contributions to the unpolarized and polarized deep inelastic structure functions is reviewed.

High Energy Physics - Phenomenology · Physics 2007-05-23 J. Blümlein

We study how the rapidity evolution of gluon transverse momentum dependent distribution changes from nonlinear evolution at small $x\ll 1$ to linear double-logarithmic evolution at moderate $x\sim 1$.

High Energy Physics - Phenomenology · Physics 2015-06-23 I. Balitsky , A. Tarasov

We summarize our recent result for a splitting function for small x evolution which includes resummed small x logarithms deduced from the leading order BFKL equation with the inclusion of running coupling effects. We compare this improved…

High Energy Physics - Phenomenology · Physics 2007-05-23 Guido Altarelli , Richard D. Ball , Stefano Forte

We study the evolution behavior of generalized parton distributions at small longitudinal momentum fraction. Particular attention is paid to the ratio of a generalized parton distribution and its forward limit, to the mixing between quarks…

High Energy Physics - Phenomenology · Physics 2008-11-26 Markus Diehl , Wolfgang Kugler

We review small $x$ contributions to perturbative evolution equations for parton distributions, and their resummation. We emphasize in particular the resummation technique recently developed in order to deal with the apparent instability of…

High Energy Physics - Phenomenology · Physics 2007-05-23 Guido Altarelli , Richard D. Ball , Stefano Forte

An approximated solution for gluon distribution from DGLAP evolution equations with NLO splitting function in the small-$x$ limit is presented. We first obtain the simplified forms of LO and NLO splitting functions in the small-$x$ limit.…

High Energy Physics - Phenomenology · Physics 2024-01-29 Jingxuan Chen , Xiaopeng Wang , Yanbing Cai , Xurong Chen , Qian Wang

We review and discuss the use of TMD, or "unintegrated", gluon distributions in the domain of small-x physics. The definitions employed, and the hazards of the naive applications of the TMD factorization and the associated gluon…

High Energy Physics - Phenomenology · Physics 2015-05-30 Emil Avsar

The status of the Milan group's work on CCFM-based phenomenology at small x, and possible directions of future investigation, are discussed.

High Energy Physics - Phenomenology · Physics 2007-05-23 G. P. Salam