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Related papers: Small-x evolution with Q dependence and unitarity

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The BFKL equation and the kT-factorization theorem are used to obtain predictions for F2 in the small Bjorken-x region over a wide range of Q**2. The dependence on the parameters, especially on those concerning the infrared region, is…

High Energy Physics - Phenomenology · Physics 2009-10-28 I. Bojak , M. Ernst

We propose a matrix evolution equation in (x,kt)-space for flavour singlet, unintegrated quark and gluon densities, which generalizes DGLAP and BFKL equations in the relevant limits. The matrix evolution kernel is constructed so as to…

High Energy Physics - Phenomenology · Physics 2010-03-25 M. Ciafaloni , D. Colferai , G. P. Salam , A. M. Stasto

The HERA data on the proton structure function, $F_2(x,Q^2)$, at very small $x$ and $Q^2$ show the dramatic departure of the logarithmic slope, $\partial F_2/\partial\log Q^2$, from theoretical predictions based on the DGLAP evolution. We…

High Energy Physics - Phenomenology · Physics 2014-11-17 N. N. Nikolaev , V. R. Zoller

Recent evidence suggests that, at small Bjorken $x$, QCD evolution drives the proton into a state of maximal entanglement. If the evolution kernel is assumed to be conformally invariant -- as is the case for the…

High Energy Physics - Phenomenology · Physics 2026-05-26 Sebastian Grieninger , Kun Hao , Dmitri E. Kharzeev , Vladimir Korepin

Effects of non-linear small-x evolution of the gluon distribution given by the Balitsky-Kovchegov equation are analyzed within the collinear approximation framework. We perform a twist decomposition of the proton structure functions F2 and…

High Energy Physics - Phenomenology · Physics 2023-12-08 Leszek Motyka , Mariusz Sadzikowski

We propose a phenomenological study of the next-to-leading Balitsky-Fadin-Kuraev-Lipatov (BFKL) approach applied to the data on the proton structure function $F_2$ measured at HERA in the small-$x_{Bj}$ region.

High Energy Physics - Phenomenology · Physics 2015-06-25 C. Royon

We construct an anomalous dimension for small x evolution which goes beyond standard fixed order perturbative evolution by including resummed small x logarithms deduced from the leading order BFKL equation with running coupling.…

High Energy Physics - Phenomenology · Physics 2008-11-26 Guido Altarelli , Richard D. Ball , Stefano Forte

I review recent results by Fadin,Lipatov and collaborators and by our group,leading to the almost complete calculation of the next-to-leading BFKL kernel,of its eigenvalues,and of the resummed gluon anomalous dimension. Qualitative…

High Energy Physics - Phenomenology · Physics 2007-05-23 Marcello Ciafaloni

The DGLAP, BFKL, modified DGLAP and modified BFKL equations are constructed in a unified partonic framework. The antishadowing effect in the recombination process is emphasized, which leads to two different small $x$ behaviors of gluon…

High Energy Physics - Phenomenology · Physics 2007-05-23 Wei Zhu , Zhenqi Shen , Jifeng Yang , Jianhong Ruan

We note the differences between the Kovchegov equation and the Balitsky-JIMWLK equations as methods of evaluating high energy hard scattering near the unitarity limit. We attempt to simulate some of the correlations absent in the Kovchegov…

High Energy Physics - Phenomenology · Physics 2008-11-26 A. H. Mueller , A. I. Shoshi

We present a determination of the parton distribution functions of the proton in which NLO and NNLO fixed-order calculations are supplemented by NLLx small-x resummation. Deep inelastic structure functions are computed consistently at…

High Energy Physics - Phenomenology · Physics 2018-05-09 Richard D. Ball , Valerio Bertone , Marco Bonvini , Simone Marzani , Juan Rojo , Luca Rottoli

Lev Lipatov was a giant in the field of strong interactions and a dominant force in high-energy QCD for many decades. His work deeply influenced both how we think about QCD and how we perform calculations in the theory. Below we describe…

High Energy Physics - Phenomenology · Physics 2019-11-11 Yuri V. Kovchegov

We indicate that the random aperiodic oscillation of the gluon distributions in a modified Balisky--Fadin--Kuraev--Lipatov (BFKL) equation has positive Lyapunov exponents. This first example of chaos in QCD evolution equations, raises the…

High Energy Physics - Phenomenology · Physics 2008-11-26 Wei Zhu , Zhenqi Shen , Jianhong Ruan

We show how it is possible to rewrite the BFKL equation for the unintegrated gluon distribution, in terms of integrated gluons, similar to that used in DGLAP. We add to our equation the next-to-leading log terms which provide exact…

High Energy Physics - Phenomenology · Physics 2015-06-19 E. G. de Oliveira , A. D. Martin , M. G. Ryskin

A unitarized BFKL equation incorporating shadowing and antishadowing corrections of the gluon recombination is proposed. This equation reduces to the Balitsky-Kovchegov evolution equation near the saturation limit. We find that the…

High Energy Physics - Phenomenology · Physics 2010-03-25 Jianhong Ruan , Zhenqi Shen , Jifeng Yang , Wei Zhu

The consistency of the BFKL equation with the renormalization group is investigated at next-to-leading log-x level.By use of Kt-factorization, it is found that,besides next-to-leading small-x resummation formulae, a leading, x-dependent…

High Energy Physics - Phenomenology · Physics 2009-10-28 Marcello Ciafaloni

We investigate the importance of unitarity corrections to parton evolution in heavy flavor production at the LHC. The gluon distribution is determined with a fit to HERA data applying a unified BFKL-DGLAP approach, in which the non-linear…

High Energy Physics - Phenomenology · Physics 2017-08-23 Krisztian Peters

We study the energy dependence of the cross-section for exclusive photoproduction of vector mesons $J/\psi$ and $\Upsilon$, using a solution to the next-to-leading order (NLO) Balitsky-Fadin-Kuraev-Lipatov (BFKL) equation. Our goal is to…

High Energy Physics - Phenomenology · Physics 2025-08-18 Martin Hentschinski , Ricardo Rangel Ramírez

We present exploratory studies of the proton structure via two distinct kinds of gluon densities: the transverse-momentum dependent functions, whose evolution is determined by the CSS equation, and the unintegrated gluon distribution, whose…

High Energy Physics - Phenomenology · Physics 2022-10-18 Francesco Giovanni Celiberto

The high-energy evolution in perturbative QCD suffers from a severe lack-of-convergence problem, due to higher order corrections enhanced by double and single transverse logarithms. We resum double logarithms to all orders within the…

High Energy Physics - Phenomenology · Physics 2016-11-23 E. Iancu , J. D. Madrigal , A. H. Mueller , G. Soyez , D. N. Triantafyllopoulos