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Related papers: Strangeness in the Meson Cloud Model

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We explore the meson cloud contribution to nucleon electromagnetic form factors in dispersion relation approach. In our calculations, experimental data on transition amplitudes for pion-nucleon scatterings are taken directly as inputs, with…

High Energy Physics - Phenomenology · Physics 2024-09-27 Ek-ong Atthaphan , Attaphon Kaewsnod , Kai Xu , Moh Moh Aung , Warintorn Sreethawong , Ayut Limphirat , Yupeng Yan

We discuss the latest CCFR determination of the strange sea density of the proton. We comment on the differences with a previous, leading--order, result and point out the relevance of quark mass effects and current non--conservation…

High Energy Physics - Phenomenology · Physics 2019-08-16 V. Barone , M. Genovese , N. N. Nikolaev , E. Predazzi , B. G. Zakharov

We point out that perturbative evolution in QCD at three loops generates a strange-antistrange asymmetry s(x)-sbar(x) in the nucleon's sea just from the fact that the nucleon has non-vanishing up and down quark valence densities. The…

High Energy Physics - Phenomenology · Physics 2009-11-10 Stefano Catani , Daniel de Florian , German Rodrigo , Werner Vogelsang

After a brief review on flavour symmetry breaking (FSB) in the unpolarized nucleon sea, we discuss theoretical predications for FSB in the polarized nucleon sea from meson cloud and `Pauli blocking'.

High Energy Physics - Phenomenology · Physics 2017-08-23 F. -G. Cao , A. I. Signal

The NuTeV anomaly of a non-universal value of the fundamental parameter sin^2\theta_W in the electroweak theory has been interpreted as an indication for new physics beyond the Standard Model. However, the observed quantity depends on a…

High Energy Physics - Phenomenology · Physics 2009-11-10 Johan Alwall , Gunnar Ingelman

Comparison of structure functions measured in neutrino and charged lepton deep inelastic scattering can be used to test basic properties of parton distribution functions such as the validity of charge symmetry. Recent experiments indicate a…

High Energy Physics - Phenomenology · Physics 2007-05-23 C. Boros , J. T. Londergan , A. W. Thomas

The calculation of the strangeness content of the nucleon and its experimental verification is a fundamental step in establishing non-perturbative QCD as the correct theory describing the structure of hadrons. It holds a role in QCD…

Nuclear Theory · Physics 2010-01-15 A. W. Thomas

The unpolarized, helicity and transversity parton distribution functions of the nucleon are studied within a convolution model where the bare nucleon is dressed by its virtual meson cloud. Using light-front time-ordered perturbation theory,…

High Energy Physics - Phenomenology · Physics 2017-05-31 S. Kofler , B. Pasquini

We use the meson cloud model to calculate $\bar{d}(x) - \bar{u}(x)$ and $ \bar{d}(x)/\bar{u}(x)$ in the proton. We show that a modification of the symmetric, perturbative part of the light quark sea provides better agreement with the ratio…

High Energy Physics - Phenomenology · Physics 2008-11-26 Mary Alberg , Ernest M. Henley

Recent deep inelastic scattering and Drell-Yan experiments have revealed a surprisingly large asymmetry between the up and down sea quark distributions in the nucleon. In this article, we review the status of the flavor asymmetry of the…

High Energy Physics - Phenomenology · Physics 2007-05-23 Jen-Chieh Peng , Gerald T. Garvey

By adopting two models of strange and antistrange quark distributions inside nucleon, the light-cone meson-baryon fluctuation model and the effective chiral quark model, we calculate the $D_s^+ - D_s^-$ asymmetry in photoproduction in the…

High Energy Physics - Phenomenology · Physics 2016-09-06 Gang Hao , Lin Li , Cong-Feng Qiao

The flavor asymmetry of the nucleon sea is discussed in an unquenched quark model for baryons in which the effects of quark-antiquark pairs (u anti-u, d anti-d and s anti-s) are taken into account in an explicit form. The inclusion of q…

Nuclear Theory · Physics 2017-11-02 R. Bijker , E. Santopinto

Recent deep inelastic scattering and Drell-Yan experiments have revealed a surprisingly large asymmetry between the up and down sea quark distributions in the nucleon. The current status of the flavor asymmetry of the nucleon sea is…

High Energy Physics - Phenomenology · Physics 2009-10-31 J. C. Peng

The possibilities to determine the flavor structure of the polarized sea (antiquark) distributions of the nucleon via vector boson $(\gamma^*, W^{\pm}, Z^0)$ production at high energy polarized hadron--hadron colliders, such as the…

High Energy Physics - Phenomenology · Physics 2009-01-07 M. Gluck , A. Hartl , E. Reya

The Chiral Quark-Soliton model provides the quark and antiquark substructure of the nucleon, which is embedded in nuclear matter. This provides a new way to asses the effects of the nuclear medium on the nucleon. We calculate nuclear…

Nuclear Theory · Physics 2009-09-29 Jason R. Smith

The chiral quark model with a nonet of Goldstone bosons can yield an adequate description of the observed proton flavor and spin structure. In a previous publication we have compared the results of a SU(3) symmetric calculation with the…

High Energy Physics - Phenomenology · Physics 2008-11-26 T. P. Cheng , Ling-Fong Li

The role of mesons, particularly the pion, in the structure of nucleons is reviewed and investigated. Since quark-antiquark pairs are likely to ``transform" into mesons at large distances, mesons are expected to contribute to nucleon…

Nuclear Theory · Physics 2016-11-03 W. Koepf , E. M. Henley , M. Alberg

This paper describes salient features of new sets of parton distributions obtained by the CTEQ Collaboration based on a comprehensive QCD global analysis of all available data. The accuracy of the new data on deep inelastic scattering…

High Energy Physics - Phenomenology · Physics 2009-10-22 James Botts , Jorge G. Morfin , Joseph F. Owens , Jianwei Qiu , Wu-Ki Tung , Harry Weerts

We consider the impact of the recent data obtained by the LHC, Tevatron, and fixed-target experiments on the nucleon quark distributions with a particular focus on disentangling different quark species. An improved determination of the…

High Energy Physics - Phenomenology · Physics 2015-02-16 S. Alekhin , J. Bluemlein , L. Caminada , K. Lipka , K. Lohwasser , S. Moch , R. Petti , R. Placakyte

Probabilities of various Fock states with strange and nonstrange quark-gluon sea contents are calculated to probe the hadronic structure. Particularly for nucleon, we find various contributions to the low energy properties from scalar,…

High Energy Physics - Phenomenology · Physics 2015-06-11 M. Batra , A. Upadhyay