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Related papers: Evolution of the gluon density in x with a running…

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We propose a new evolution equation for the gluon density relevant for the region of small $x_B$. It generalizes the GLR equation and allows deeper penetration in dense parton systems than the GLR equation does. This generalization consists…

High Energy Physics - Phenomenology · Physics 2009-09-25 E. Laenen , E. Levin

Calculations of deep inelastic processes (DIS) to next-to-next to leading order are discussed. Fitting $ep$ experiment in the range $2.5\leq Q^2\leq 230 GeV^2$, we find the coupling $\alpha_s(M_Z^2)=0.1163\pm0.0023$. We also get the gluon…

High Energy Physics - Phenomenology · Physics 2009-10-31 J. Santiago , F. J. Yndurain

Accurate gluon densities at small $x$ are essential for reducing theoretical uncertainties in collider predictions, yet remain one of the least constrained ingredients in global analyses. We report recent advances in the resummation of…

High Energy Physics - Phenomenology · Physics 2025-12-02 Francesco Giovanni Celiberto , Marco Bonvini

Measurements involving the gluon spin density, Delta G=G++ - G+-, can play an important role in the quantitative understanding of proton structure. To demonstrate this, we show that the shape of the gluon asymmetry, A(x,t)=Delta…

High Energy Physics - Phenomenology · Physics 2011-07-27 Yevgeny Binder , Gordon P. Ramsey , Dennis Sivers

The prospects of a direct extraction of the proton's gluon density in next-to-leading order via jet rates in deeply inelastic scattering are studied. The employed method is based on the Mellin transform, and can be applied, in principle, to…

High Energy Physics - Phenomenology · Physics 2007-05-23 D. Graudenz , M. Hampel , A. Vogt

In the following article we describe our measurement of the proton structure function $F_2$ and of the gluon momentum density $xg$ in $ep$ collisions with the ZEUS detector at HERA in 1993. The results for $F_2$ confirm our measurement from…

High Energy Physics - Experiment · Physics 2007-05-23 J. I. Fleck

In this paper, the evolutions of longitudinal proton structure function have been obtained at small-$x$ up to next-to-next-to-leading order using a hard Pomeron behavior. In our paper, evolutions of gluonic as well as heavy longitudinal…

High Energy Physics - Phenomenology · Physics 2014-12-05 G. R. Boroun , B. Rezaei , J. K. Sarma

The running of the QCD coupling is incorporated into the infrared evolution equations for the flavour structure function g_1. The explicit expressions for g_1 including the total resummation of the double-logarithmic contributions and…

High Energy Physics - Phenomenology · Physics 2008-11-26 B. I. Ermolaev , M. Greco , S. I. Troyan

We obtain an approximate analytical form of the gluon distribution using the GLAP equation with a factorization ansatz,and test its validity by comparing it with that of Gluck,Reya and Vogt at low $x$ regime. We also present calculations of…

High Energy Physics - Phenomenology · Physics 2014-11-17 Ranjita Deka , D. K. Choudhury

We address a long standing problem concerning the scale behaviour of parton densities in the low $x$, low $Q^2$ domain. We emphasize the important role of absorptive corrections at low $x$ and use knowledge of diffractive deep inelastic…

High Energy Physics - Phenomenology · Physics 2019-01-30 M. R. Pelicer , E. G. de Oliveira , A. D. Martin , M. G. Ryskin

We study 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 2015-09-30 I. Balitsky , A. Tarasov

The gluon distribution is dominated by the hard pomeron at small $x$ and all $Q^2$, with no soft-pomeron contribution. This describes well not only the DGLAP evolution of the hard-pomeron part of $F_2(x,Q^2)$, but also charm photoproduction…

High Energy Physics - Phenomenology · Physics 2014-11-17 A Donnachie , P V Landshoff

The running coupling is introduced into the equation for propagation of the pomeron in the nucleus via the bootstrap relation. The resulting equation coincides with the one obtained in the colour dipole formalism by summing contributions…

High Energy Physics - Phenomenology · Physics 2008-11-26 M. A. Braun

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

Exclusive J/psi production, gamma* p -> J/psi p, offers a unique opportunity to determine the gluon density of the proton in the small x domain. We use the available HERA data to determine the gluon distribution in the region 10^{-4} <~ x…

High Energy Physics - Phenomenology · Physics 2008-11-26 A. D. Martin , C. Nockles , M. Ryskin , T. Teubner

We solve a unified integral equation to obtain the $x, Q_T$ and $Q$ dependence of the gluon distribution of a proton in the small $x$ regime; where $x$ and $Q_T$ are the longitudinal momentum fraction and the transverse momentum of the…

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

The equation for the hard pomeron with a running coupling introduced on the basis of the bootstrap requirement is solved numerically. Two supercritical pomerons are found with the intercept minus 1 of the leading one of the order 0.35-0.5…

High Energy Physics - Phenomenology · Physics 2009-10-28 Mikhail Braun , Gian Paolo Vacca , Giovanni Venturi

The $k_{\perp}$ dependent gluon distribution is calculated accounting for the resummation of small~$x$ effects due to the Lipatov equation. It is represented by a convolution of a gluon density in the collinear limit and a universal…

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

We describe the energy distribution of hard gluons travelling through a dense quark-gluon plasma whose temperature increases linearly with time, within a probabilistic perturbative approach. The results were applied to the thermalization…

High Energy Physics - Phenomenology · Physics 2022-01-21 F. G. Ben , M. V. T. Machado

The behavior of the gluon density in nuclei is investigated in the framework of the rescaling model.

High Energy Physics - Phenomenology · Physics 2022-11-28 N. A. Abdulov , A. V. Kotikov , A. V. Lipatov