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Related papers: Parton Densities in a Nucleon

200 papers

We present an improved determination of the proton structure functions $F_{2}$ and $xF_{3}$ from the CCFR $\nu $-Fe deep inelastic scattering (DIS) experiment. Comparisons to high-statistics charged-lepton scattering results for $F_{2}$…

High Energy Physics - Experiment · Physics 2008-11-26 CCFR Collaboration , W. Seligman

We investigate the nuclear shadowing mechanism in the context of perturbative QCD and the Glauber multiple scattering model. Using recent HERA data on nucleon structure function at small $x$, we put stringent constrains on the nucleon gluon…

High Energy Physics - Phenomenology · Physics 2009-10-30 Zheng Huang , Hung Jung Lu , Ina Sarcevic

It is usually assumed -- following the parton model -- that the leading-twist structure functions measured in deep inelastic lepton-proton scattering are simply the probability distributions for finding quarks and gluons in the target…

High Energy Physics - Phenomenology · Physics 2009-09-11 S. J. Brodsky

The gluon distribution in nuclei plays a pivotal role in understanding quantum chromodynamics (QCD) under extreme nuclear environments, yet remains poorly constrained compared to quark distributions. Coherent \jpsi photoproduction in…

High Energy Physics - Phenomenology · Physics 2025-02-14 Pengzhong Lu , Zebo Tang , Xin Wu , Wangmei Zha

We study experimentally observable signals for nonlinear QCD dynamics in deep inelastic scattering (DIS) at small Bjorken variable $x$ and moderate virtuality $Q^2$, by quantifying differences between the linear…

High Energy Physics - Phenomenology · Physics 2022-06-17 Nestor Armesto , Tuomas Lappi , Heikki Mäntysaari , Hannu Paukkunen , Mirja Tevio

Quantum chromodynamics (QCD) is the theory of strong interactions of quarks and gluons collectively called partons, the basic constituents of all nuclear matter. Its non-abelian character manifests in nature in the form of two remarkable…

High Energy Physics - Phenomenology · Physics 2021-08-24 Astrid Morreale , Farid Salazar

We study the nuclear shadowing effect in the context of Glauber-Gribov multiple-scattering model and perturbative QCD. We find that at small x, the $Q^2$ evolution of the shadowing is much slower than the DGLAP evolution, due to the…

High Energy Physics - Phenomenology · Physics 2007-05-23 Ina Sarcevic

In this talk, I will argue that the HERA experimental data show that the typical parameter ($\kappa$) responsible for the value of the shadowing corrections (SC) in DIS is so large that the BFKL Pomeron is hidden under SC. The SC turn out…

High Energy Physics - Phenomenology · Physics 2007-05-23 Eugene Levin

We perform analysis of the small x non-linear evolution equation formulated in momentum space supplemented by higher order terms. The equation is defined in wide range of transverse momentum and longitudinal momentum fraction extending…

High Energy Physics - Phenomenology · Physics 2025-06-03 Krzysztof Kutak , Wanchen Li , Anna Stasto , Robert Straka

The corrections of the gluon fusion to the BFKL equation in a unified partonic framework are studied. This modified BFKL equation predicts a stronger shadowing, which suppresses the gluon density and even leads to the gluon disappearance…

High Energy Physics - Phenomenology · Physics 2016-03-10 Wei Zhu , Zhenqi Shen , Jianhong Ruan

Gluon dressing of the light quarks within hadrons is very strong and extremely important in that it dynamically generates most of the observable mass through the breaking of chiral symmetry. The quark and gluon parton densities, $q(x)$ and…

High Energy Physics - Phenomenology · Physics 2021-10-13 Adam Freese , Ian C. Cloët , Peter C. Tandy

We study the dipole picture for the description of the deep inelastic scattering, focusing on the structure functions which are driven directly by the gluon distribution. One performs estimates using the effective dipole cross section given…

High Energy Physics - Phenomenology · Physics 2015-06-25 M. B. Gay Ducati , M. V. T. Machado

Parton distributions can be defined in terms of the entropy of entanglement between the spatial region probed by deep inelastic scattering (DIS) and the rest of the proton. For very small $x$, the proton becomes a maximally entangled state.…

High Energy Physics - Phenomenology · Physics 2021-09-08 Dmitri E. Kharzeev , Eugene Levin

Using the QCD dipole picture of the BFKL pomeron, the gluon contribution to the cross-section for single diffractive dissociation in deep-inelastic high-energy scattering is calculated. The resulting contribution to the proton diffractive…

High Energy Physics - Phenomenology · Physics 2008-11-26 A. Bialas , R. Peschanski

We analyze deep inelastic scattering at small Bjorken x, using the approximate conformal invariance of QCD at high energies. Hard pomeron exchanges are resummed eikonally, restoring unitarity at large values of the phase shift in the dual…

High Energy Physics - Phenomenology · Physics 2009-03-19 Lorenzo Cornalba , Miguel S. Costa

Saturation and geometrical scaling (GS) of gluon distributions are a consequence of the non-linear evolution equations of QCD. We argue that in pp GS holds for the inelastic cross-section rather than for the multiplicity distributions. We…

High Energy Physics - Phenomenology · Physics 2016-07-15 Michal Praszalowicz

Nuclear shadowing corrections to the structure functions of deep inelastic scattering on intermediate-mass nuclei are calculated at very small values of Bjorken x and small values of Q^2 (Q^2<5 Gev^2). The two-component approach developed…

High Energy Physics - Phenomenology · Physics 2020-09-02 Edgar V. Bugaev , Boris V. Mangazeev

The recently proposed nonlinear evolution equation \cite{Kutak:2013hda} for unintegrated gluon densities valid for large values of the QCD coupling constant $\bar{\alpha} _s$ is presented. In particular we outline its derivation, numerical…

High Energy Physics - Phenomenology · Physics 2014-06-24 Krzysztof Kutak

Low-Q^2 photons do not resolve partons in the proton, which gives problems when applying the deep inelastic scattering formalism, such as an unphysical, negative gluon density extracted from data. Considering instead hadronic fluctuations…

High Energy Physics - Phenomenology · Physics 2008-11-26 Johan Alwall , Gunnar Ingelman

We propose new Transverse Momentum Dependent (TMD) gluon densities in nuclei. Our method is based on a combination of the color dipole scattering formalism, within which we interpret the nuclear deep inelastic structure functions…

High Energy Physics - Phenomenology · Physics 2025-05-06 A. V. Lipatov , G. I. Lykasov , M. A. Malyshev