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Related papers: Proton Sea Quark Flavour Asymmetry and Roper Reson…

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The flavor asymmetry of the nucleon sea, i.e., the excess of $d\bar{d}$ quark-antiquark pairs over $u\bar{u}$ ones in the proton can be explained by several different models; therefore, it is a challenge to discriminate these models from…

High Energy Physics - Phenomenology · Physics 2010-06-17 Lijing Shao , Yong-Jun Zhang , Bo-Qiang Ma

I review progress in calculating strange quark and antiquark distributions of the nucleon using the meson cloud model. This progress parallels that of the meson cloud model, which is now a useful theoretical basis for understanding symmetry…

Nuclear Theory · Physics 2015-05-18 A. I. Signal

After a pedagogical review of the simple constituent quark model and deep inelastic sum rules, we describe how a quark sea as produced by the emission of internal Goldstone bosons by the valence quarks can account for the observed features…

High Energy Physics - Phenomenology · Physics 2009-10-30 Ling-Fong Li , T. P. Cheng

We take into account the sigma meson cloud effect in the meson cloud model to calculate the distributions of light flavor sea quarks in the proton. Our calculation gives a better description of the data for $\bar{d}(x)/\bar{u}(x)$. We also…

High Energy Physics - Phenomenology · Physics 2009-11-10 Feng Huang , Rong-Guang Xu , Bo-Qiang Ma

We investigate the feasibility of constraining parton distribution functions in the proton through a comparison with data on semi-inclusive deep-inelastic lepton-nucleon scattering. Specifically, we reweight replicas of these distributions…

High Energy Physics - Phenomenology · Physics 2017-11-29 Ignacio Borsa , Rodolfo Sassot , Marco Stratmann

Using DGLAP evolution equation with the corrections of parton recombinations, the flavor asymmetric sea quark distributions in the proton are first extracted from the available experimental data with the global QCD analysis method.…

High Energy Physics - Phenomenology · Physics 2015-12-10 Wei Zhu , Rong Wang , Jianhong Ruan , Xurong Chen , Pengming Zhang

We investigate the flavour and quark-antiquark structure of the polarized nucleon by calculating the parton distribution functions of the nucleon sea using the meson cloud model. We find that the SU(2) flavor symmetry in the light antiquark…

High Energy Physics - Phenomenology · Physics 2009-03-02 Fu-Guang Cao , A. I. Signal

Parton distributions derived from a chiral quark model that generates an excess of down quarks and antiquarks in the proton's sea satisfactorily describe the measured yields of muon pairs produced in proton-nucleus collisions. Comparison of…

High Energy Physics - Phenomenology · Physics 2009-05-05 Estia J. Eichten , Ian Hinchliffe , Chris Quigg

We derive a Menta Carlo method to simulate kinetic equilibrium ensemble, and get the same sea-quark flavor asymmetry as the linear equations method in statistical model. In the recent paper, we introduce the spilt factors to indicate the…

High Energy Physics - Phenomenology · Physics 2010-10-27 Bin Zhang , Yong-Jun Zhang

We employ a continuum approach to the three valence-quark bound-state problem in relativistic quantum field theory to predict a range of properties of the proton's radial excitation and thereby unify them with those of numerous other…

The recent progress on our understanding of the flavor structure of unpolarized and polarized nucleon sea is reviewed. The large flavor asymmetry between the up and down sea quark distributions is now well established. This asymmetry…

High Energy Physics - Phenomenology · Physics 2008-11-26 Jen-Chieh Peng

The Gottfried sum rule violation reported by the New Muon Collaboration(NMC) was interpreted as indication for a flavour asymmetry of the sea quark in the nucleons. We investigate the alternative possibility that isospin symmetry between…

High Energy Physics - Phenomenology · Physics 2009-10-22 Bo-Qiang Ma , Andereas Schaefer , Walter Greiner

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

We apply the Meson Cloud Model to the calculation of nonsinglet parton distributions in the nucleon sea, including the octet and the decuplet cloud baryon contributions. We give special attention to the differences between nonstrange and…

High Energy Physics - Phenomenology · Physics 2014-11-17 F. Carvalho , F. O. Durães , F. S. Navarra , M. Nielsen , F. M. Steffens

The recent global analysis of helicity parton distributions, which takes into account available data from inclusive and semi-inclusive polarized deep inelastic scattering, as well as from polarized proton-proton scattering at RHIC, appears…

High Energy Physics - Phenomenology · Physics 2010-03-15 M. Wakamatsu

In this study, the proton is taken as an ensemble of quark-gluon Fock states. Using the principle of detailed balance, the probabilities of finding every Fock states of the proton are obtained without any parameter. A new origin of the…

High Energy Physics - Phenomenology · Physics 2008-11-26 Yong-Jun Zhang , Bin Zhang , Bo-Qiang Ma

We formulate a light-front spectator model for the proton that incorporates the presence of light sea quarks. In this particular model, the sea quarks are seen as active partons, whereas the remaining components of the proton are treated as…

High Energy Physics - Phenomenology · Physics 2023-12-05 Poonam Choudhary , Dipankar Chakrabarti , Chandan Mondal

A striking prediction of several extensions of the constituent quark model, including the unquenched quark model, the pion cloud model and the chiral quark model, is a proportionality relationship between the quark sea asymmetry and the…

High Energy Physics - Phenomenology · Physics 2016-11-28 Emanuele R. Nocera , Elena Santopinto

We calculate with chiral symmetry the parton contents of the proton based on a two-component wave function. The calculation results give significant sea-quark contents and, especially, the intrinsic gluon polarization produced at a more…

High Energy Physics - Phenomenology · Physics 2009-10-28 Chung-Yi Wu

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
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