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Related papers: Parton Densities in a Nucleon

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In order to obtain polarised parton densities we have made next to leading order QCD fit using experimental data on deep inelastic structure functions on nucleons. This fit is compared with the updated fit to coresponding spin asymmetries.…

High Energy Physics - Phenomenology · Physics 2009-11-07 Jan Bartelski , Stanislaw Tatur

We consider a nonlinear evolution equation recently proposed to describe the small-$x$ hadronic physics in the regime of very high gluon density. This is a functional Fokker-Planck equation in terms of a classical random color source, which…

High Energy Physics - Phenomenology · Physics 2009-10-31 Edmond Iancu , Andrei Leonidov , Larry McLerran

The gluon distribution of a nucleon propagating through a nucleus can change depending on how far the penetration depth is. It is a nonperturbative process that we describe by an evolution equation. The kernel of the integral equation is to…

High Energy Physics - Phenomenology · Physics 2007-05-23 R. C. Hwa

We review the phenomenon of color coherence in quantum chromodynamics (QCD), its implications for hard and soft processes with nuclei, and its experimental manifestations. The relation of factorization theorems in QCD with color coherence…

High Energy Physics - Phenomenology · Physics 2014-11-17 L. Frankfurt , V. Guzey , M. Strikman

In the past year, polarized deep inelastic scattering experiments at CERN and SLAC have obtained structure function measurements off proton, neutron and deuteron targets at a level of precision never before achieved. The measurements can be…

High Energy Physics - Phenomenology · Physics 2010-04-06 T. Gehrmann , W. J. Stirling

Deep inelastic structure functions $F_2^A(x)$ are investigated in a $Q^2$ rescaling model with parton recombination effects. We find that the model can explain experimentally measured $F_2^A(x)$ structure functions reasonably well in the…

High Energy Physics - Phenomenology · Physics 2008-11-26 S. Kumano

The proton spin puzzle is a longstanding problem in high-energy nuclear physics: how the proton spin distributes among the spin and orbital angular momenta of the quarks and gluons inside. Two of the unresolved pieces of the puzzle are the…

High Energy Physics - Phenomenology · Physics 2023-06-29 Yossathorn Tawabutr

Progresses towards the calculation and the understanding of NLO/NLL contributions to Deep Inelastic Scattering at low x with gluon saturation are being reviewed.

High Energy Physics - Phenomenology · Physics 2015-06-03 Guillaume Beuf

We show estimates for shadowing of gluons at small values of $x$, appropriate to RHIC and LHC experiments using a new evolution equation which takes into account the effects of gluon recombination to all orders in gluon density. We show…

High Energy Physics - Phenomenology · Physics 2007-05-23 J. Jalilian-Marian

We present a QCD-based model where rescattering between final state partons in deep inelastic scattering leads to events with large rapidity gaps and a leading proton. In the framework of this model the amplitude for multiple gluon…

High Energy Physics - Phenomenology · Physics 2011-01-05 Roman Pasechnik , Rikard Enberg , Gunnar Ingelman

In this paper we demonstrate that the dense system of partons (gluons) can be produced in dilute-dilute system scattering, using the example of dipole-dipole collisions. This increase in density stems from the intensive gluon cascades that…

High Energy Physics - Phenomenology · Physics 2015-06-17 Eugene Levin

Parton distributions in the small $x$ region are numerically predicted by using a modified DGLAP equation with the GRV-like input distributions. We find that gluon recombination at twist-4 level obviously suppresses the rapid growth of…

High Energy Physics - Phenomenology · Physics 2014-11-17 Wei Zhu , Jian-hong Ruan , Ji-feng Yang , Zhen-qi Shen

The perturbative QCD predicts that the growth of the gluon density at small-$x$ (high energies) should saturate, forming a Color Glass Condensate (CGC), which is described in mean field approximation by the Balitsky-Kovchegov (BK) equation.…

High Energy Physics - Phenomenology · Physics 2014-11-20 M. A. Betemps , V. P. Goncalves , J. T. de Santana Amaral

The contribution of quarks with masses m >> Lambda_QCD is the only part of the structure functions in deep-inelastic scattering (DIS) which is not yet known at the next-to-next-to-leading order (NNLO) of perturbative QCD. We present…

High Energy Physics - Phenomenology · Physics 2016-08-09 H. Kawamura , N. A. Lo Presti , S. Moch , A. Vogt

The parton distributions in the proton are evaluated dynamically using a nonlinear QCD evolution equation - the DGLAP equation with twist-4 (the GLR-MQ-ZSR) corrections - starting from a low scale $\mu^2$, where the nucleon consists of…

High Energy Physics - Phenomenology · Physics 2014-09-11 Xurong Chen , Jianhong Ruan , Rong Wang , Pengming Zhang , Wei Zhu

We report a semi-analytical approach for the solution of the nonlinear Gribov-Levin-Ryskin-Mueller-Qiu (GLR-MQ) evolution equation for sea quark distribution and investigate the effect of gluon shadowing on the small-x and moderate-Q^2…

High Energy Physics - Phenomenology · Physics 2018-08-09 Mayuri Devee

Decoding the internal structure of the proton is a fundamental challenge in physics. Historically, any new discovery about the proton has fuelled advances in several scientific fields. We have reported that gluons inside the proton…

High Energy Physics - Phenomenology · Physics 2025-10-08 Wei Zhu , Jianhong Ruan , Xurong Chen , Yuchen Tang

Parton branching solutions of QCD evolution equations have recently been studied to construct both collinear and transverse momentum dependent (TMD) parton distributions. In this formalism, a soft-gluon resolution scale is introduced to…

High Energy Physics - Phenomenology · Physics 2022-07-28 S. Sadeghi Barzani

We formulate a light-front spectator model for the proton incorporating the gluonic degree of freedom. In this model, at high energy scattering of the proton, the active parton is a gluon and the rest is viewed as a spin-$\frac{1}{2}$…

High Energy Physics - Phenomenology · Physics 2023-07-26 Dipankar Chakrabarti , Poonam Choudhary , Bheemsehan Gurjar , Raj Kishore , Tanmay Maji , Chandan Mondal , Asmita Mukherjee

The proton structure function is re-deduced from the data of deep inelastic electron-proton scattering after enhanced correction that is made due to the multiple scattering effect. The Glauber approach is used to account for the multiple…

High Energy Physics - Phenomenology · Physics 2007-05-23 N. M. Hassan , W. R. El-Harby , R. W. El-Moualed And M. T. Hussein