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Related papers: Geometric Scaling above the Saturation Scale

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Considering the BFKL and DGLAP QCD evolution equations for structure functions, we discuss the possibility of unifying them in the whole $x$ and $Q^2$ range. We emphasize that the main problem is related to the constraint of angular…

High Energy Physics - Phenomenology · Physics 2007-05-23 S. Wallon

We perform numerical studies of the BFKL and CCFM equations for the unintegrated gluon distribution supplemented with an absorptive boundary which mimics saturation. For the BFKL equation, this procedure yields the same results for the…

High Energy Physics - Phenomenology · Physics 2009-11-19 Emil Avsar , Edmond Iancu

Standard perturbative calculations lead to pathologically large NLO corrections to low-$x_{Bj}$ evolution equations like BFKL and BK. Using a more refined treatment of kinematics in mixed-space, relevant when gluon saturation sets on, one…

High Energy Physics - Phenomenology · Physics 2015-06-12 Guillaume Beuf

The transverse momentum distribution of soft hadrons and jets that accompany central hard-scattering production at hadron colliders is of great importance, since it has a direct bearing on the ability to separate new physics signals from…

High Energy Physics - Phenomenology · Physics 2014-11-17 V. A. Khoze , A. D. Martin , M. G. Ryskin , W. J. Stirling

I calculate the anomalous dimension governing the Q^2 evolution of the gluon (and structure functions) coming from the running coupling BFKL equation. This may be expressed in an exact analytic form, up to a small ultraviolet renormalon…

High Energy Physics - Phenomenology · Physics 2009-10-31 R. S. Thorne

We use the BLM procedure to eliminate the renormalization scale ambiguity in the evolution equation for the non-singlet deep-inelastic structure function $F_2^{\text NS}(x,Q).$ The scale of the QCD coupling in the $\overline{\text{MS}}$…

High Energy Physics - Phenomenology · Physics 2009-10-28 Wing Kai Wong

The CCFM equation and its extended form with a quadratic term (KGBJS equation) are solved with fixed and running coupling constant. The solution of the KGBJS equation is compared to gluon densities resulting from the CCFM and BK equations.…

High Energy Physics - Phenomenology · Physics 2013-11-13 Krzysztof Kutak , Dawid Toton

The numerical solutions of the non-linear evolution equation are shown to display the ``geometric'' scaling recently discovered in the experimental data. The phenomena hold both for proton and nucleus targets for all $x$ below $10^{-2}$ and…

High Energy Physics - Phenomenology · Physics 2009-01-07 M. Lublinsky

In order to get an estimate of the homogeneity of the distribution of matter in a fast hadron or nucleus, we compute the correlations of the saturation scales Q_s between different points in impact-parameter space, in some specific…

High Energy Physics - Phenomenology · Physics 2010-05-19 A. H. Mueller , S. Munier

We discuss the distinct approaches for high density QCD (hdQCD) in the asymptotic regime of large values of parton density. We derive the AGL equation for running coupling constant and obtain the asymptotic solution, demonstrating that the…

High Energy Physics - Phenomenology · Physics 2007-05-23 M. B. Gay Ducati , V. P. Gonçalves

We find approximate solutions to the renormalization group equation which governs the quantum evolution of the effective theory for the Color Glass Condensate. This is a functional Fokker-Planck equation which generates in particular the…

High Energy Physics - Phenomenology · Physics 2010-11-30 Edmond Iancu , Larry McLerran

In this work we aim to gain qualitative insight on the far-from-equilibrium behavior of the gluon plasma produced in the early stages of a heavy-ion collision. It was recently discovered arXiv:1810.10554 that the distribution functions of…

High Energy Physics - Phenomenology · Physics 2022-06-08 Jasmine Brewer , Bruno Scheihing-Hitschfeld , Yi Yin

Transverse momentum integrated multiplicities in the central region of pp collisions at LHC energies satisfy Koba-Nielsen-Olesen scaling. We attempt to relate this finding to multiplicity distributions of soft gluons. KNO scaling emerges if…

High Energy Physics - Phenomenology · Physics 2012-09-20 Adrian Dumitru , Elena Petreska

The initial distribution of gluons at the very early times after a high energy heavy ion collision is described by the bulk scale $Q_s$ of gluon saturation in the nuclear wavefunction. The subsequent evolution of the system towards kinetic…

High Energy Physics - Phenomenology · Physics 2010-11-30 Jefferson Bjoraker , Raju Venugopalan

A natural framework to understand the energy dependence of bulk observables from lower energy experiments to the LHC is provided by the Color Glass Condensate, which leads to a "geometrical scaling" in terms of an energy dependent…

High Energy Physics - Phenomenology · Physics 2011-08-25 T. Lappi

Recent estimates that Color Glass Condensate initial conditions may generate a larger initial eccentricity for noncentral relativistic heavy ion collisions (relative to the initial eccentricity assumed in earlier hydrodynamic calculations)…

Nuclear Theory · Physics 2008-11-26 T. Lappi , R. Venugopalan

In this paper the semi-classical approach to the solution of non-linear evolution equation is developed. We found the solution in the entire kinematic region to the non-linear evolution equation that governs the dynamics in the high parton…

High Energy Physics - Phenomenology · Physics 2008-12-22 S. Bondarenko , M. Kozlov , E. Levin

We study the effects of including a running coupling constant in high-density QCD evolution. For fixed coupling constant, QCD evolution preserves the initial dependence of the saturation momentum $Q_s$ on the nuclear size $A$ and results in…

High Energy Physics - Phenomenology · Physics 2009-11-10 J. L. Albacete , N. Armesto , J. G. Milhano , C. A. Salgado , U. A. Wiedemann

We propose a stochastic particle model in (1+1)-dimensions, with one dimension corresponding to rapidity and the other one to the transverse size of a dipole in QCD, which mimics high-energy evolution and scattering in QCD in the presence…

High Energy Physics - Phenomenology · Physics 2008-11-26 E. Iancu , J. T. de Santana Amaral , G. Soyez , D. N. Triantafyllopoulos

We argue that the use of the universal unintegrated gluon distribution and the $k_T$ (or high energy) factorization theorem provides the natural framework for describing observables at small x. We introduce a coupled pair of evolution…

High Energy Physics - Phenomenology · Physics 2014-11-17 J. Kwiecinski , A. D. Martin , A. M. Stasto