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Related papers: Quark Asymmetries in Nucleons

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Based on quantum fluctuations in momentum and of the proton into meson-baryon pairs, we develop a physical model for the non-perturbative x-shape of parton density functions in the proton. The model describes the proton structure function…

High Energy Physics - Phenomenology · Physics 2007-05-23 Johan Alwall , Gunnar Ingelman

We have developed a physical model for the non-perturbative x-shape of parton density functions in the proton, based on Gaussian fluctuations in momenta, and quantum fluctuations of the proton into meson-baryon pairs. The model describes…

High Energy Physics - Phenomenology · Physics 2007-05-23 Johan Alwall

A physical model for parton densities in hadrons, based on Gaussian momentum fluctuations of partons and hadronic baryon-meson fluctuations, is presented. The model has previously been shown to describe proton structure function data, and…

High Energy Physics - Phenomenology · Physics 2007-05-23 Johan Alwall

A physical model is presented for the non-perturbative parton distributions in the nucleon. This is based on quantum fluctuations of the nucleon into baryon-meson pairs convoluted with Gaussian momentum distributions of partons in hadrons.…

High Energy Physics - Phenomenology · Physics 2019-08-14 Andreas Ekstedt , Hazhar Ghaderi , Gunnar Ingelman , Stefan Leupold

Although the distributions of sea quarks and antiquarks generated by leading-twist QCD evolution through gluon splitting $g \rightarrow \bar q q$ are necessarily CP symmetric, the distributions of nonvalence quarks and antiquarks which are…

High Energy Physics - Phenomenology · Physics 2009-09-11 S. J. Brodsky , B. -Q. Ma

The strange sea of the proton is generally assumed to have quark - antiquark symmetry. However it has been known for some time that non-perturbative processes involving the meson cloud of the proton may break this symmetry. Recently this…

High Energy Physics - Phenomenology · Physics 2009-11-10 F. G. Cao , A. I. Signal

We investigate an asymmetry in the angular distribution of hard elastic proton-neutron scattering with respect to 90deg center of mass scattering angle. We demonstrate that the magnitude of the angular asymmetry is related to the…

High Energy Physics - Phenomenology · Physics 2009-12-08 Carlos G. Granados , Misak M. Sargsian

We analyze the non-perturbative structure of the strange sea of the nucleon within a meson cloud picture. In a low $Q^2$ approach in which the nucleon is viewed as a three valon bound state, we evaluate the probability distribution of an…

High Energy Physics - Phenomenology · Physics 2009-10-31 H. R. Christiansen , J. Magnin

The quark and gluon structure of the proton has been under intense experimental and theoretical investigation for five decades. Even for the distributions of the well-studied valence quarks, challenges such as the value of the down quark to…

Nuclear Experiment · Physics 2019-03-27 D. F. Geesaman , P. E. Reimer

Asymmetries in the quark momentum distributions in the proton reveal fundamental aspects of strong interaction physics. Differences between u-bar and d-bar quarks in the proton sea provide insight into the dynamics of the pion cloud around…

High Energy Physics - Phenomenology · Physics 2014-11-17 W. Melnitchouk

At a low resolution scale with $Q^2={\mu}^2$ corresponding to the nucleon bound state; deep inelastic unpolarized structure functions $F_1(x,{\mu}^2)$ and $F_2(x,{\mu}^2)$ are derived with correct support using the symmetric part of the…

High Energy Physics - Phenomenology · Physics 2014-11-17 N. Barik , R. N. Mishra

We demonstrate that a nonzero strangeness contribution to the spacelike electromagnetic form factor of the nucleon is evidence for a strange-antistrange asymmetry in the nucleon's light-front wave function, thus implying different…

The hyperfine interactions of the constituent quark model provide a natural explanation for many nucleon properties, including the Delta-N splitting, the charge radius of the neutron, and the observation that the proton's quark distribution…

High Energy Physics - Phenomenology · Physics 2014-11-17 Nathan Isgur

Sea quark distributions in the nucleon have naively been expected to be generated perturbatively by gluon splitting. In this case, there is no reason for the light quark and anti-quark sea distributions to be different. No asymmetries in…

High Energy Physics - Phenomenology · Physics 2015-06-25 R. Vogt

Nucleon momentum distributions at various densities and isospin-asymmetries for nuclear matter are investigated systematically within the extended Bruecker-Hartree-Fock approach.The shapes of the normalized momentum distributions varying…

Nuclear Theory · Physics 2019-11-27 Z. X. Yang , X. L. Shang , G. C. Yong , W. Zuo , Y. Gao

We derive the nucleon non-perturbative sea-quark distributions coming from a composite model involving quarks and hadronic degrees of freedom. The model predicts a definite structured quark-antiquark asymmetry in the nucleon sea.

High Energy Physics - Phenomenology · Physics 2007-05-23 H. R. Christiansen , J. Magnin

We review recent experimental and theoretical developments in the study of the sea quark structure of the proton. In the light quark sector, we analyse the recent pp and pD Drell-Yan data from the E866/NuSea experiment at Fermilab, and…

High Energy Physics - Phenomenology · Physics 2007-05-23 W. Melnitchouk

We employ a model of nuclear structure that takes into account the quark substructure of the baryons to understand the behavior of static two-point correlation functions of meson fields in dense nuclear matter. We show that these…

Nuclear Theory · Physics 2025-09-23 Theo F. Motta , Gastão Krein

We report the correction from the asymmetric strange-antistrange sea of the nucleon by using both the light-cone baryon-meson fluctuation model and the chiral quark model, and show that a significant part of the NuTeV anomaly can be…

High Energy Physics - Phenomenology · Physics 2009-11-11 Bo-Qiang Ma

The fundamental building blocks of the proton, quarks and gluons, have been known for decades. However, we still have an incomplete theoretical and experimental understanding of how these particles and their dynamics give rise to the…

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