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Related papers: The s-s(bar) asymmetry in nucleon and "NuTeV anoma…

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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

We study the $s-\bar s$ asymmetry in the nucleon sea using a model in which the proton wave function includes a Kaon-Hyperon Fock state. Parameters of the model are fixed by fitting the $s-\bar s$ asymmetry obtained from global fits to Deep…

High Energy Physics - Phenomenology · Physics 2007-10-23 C. Avila , I. Monroy , J. C. Sanabria , J. Magnin

We evaluate the medium effects in nucleon which can induce an asymmetry of the strange sea. The short-distance effects determined by the weak interaction can give rise to $\delta m\equiv \Delta m_s-\Delta m_{\bar s}$ where $\Delta m_{s(\bar…

High Energy Physics - Phenomenology · Physics 2009-11-07 Xue-Qian Li , Xiao-Bing Zhang , Bo-Qiang Ma

Interest in the strange nucleon sea has been renewed when it was realized that the strangeness asymmetry $s^-=s-\bar{s}$ plays a prominent role in the interpretation of the NuTeV weak mixing angle anomaly. I review the NLO QCD calculation…

High Energy Physics - Phenomenology · Physics 2007-05-23 S. Kretzer

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

The study of $ s-\bar s $ asymmetry is essential to better understand of the structure of nucleon and also the perturbative and nonperturbative mechanisms for sea quark generation. Actually, the nature and dynamical origins of this…

High Energy Physics - Phenomenology · Physics 2018-03-09 Muhammad Goharipour

We extend to the strange quarks and antiquarks, the statistical approach of parton distributions and we calculate the strange quark asymmetry $s-\bar s$. We find that the asymmetry is small, positive in the low $x$ region and negative in…

High Energy Physics - Phenomenology · Physics 2008-11-26 Claude Bourrely , Franco Buccella , Jacques Soffer

Two phenomenological models which give opposite predictions for the $s$-${\bar s}$ asymmetry in the nucleon sea are re-analyzed carefully. It is pointed out that although the quantitative results in both models depend dramatically on the…

High Energy Physics - Phenomenology · Physics 2009-10-31 Fu-Guang 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

Distinctions between quark to $\Lambda$ and $\bar\Lambda$ longitudinal spin transfers in the semi-inclusive deep inelastic scattering process were observed by the E665 and COMPASS Collaborations. There are suggestions that the difference…

High Energy Physics - Phenomenology · Physics 2017-03-13 Xiaozhen Du , Bo-Qiang Ma

Our recent theoretical analysis based on the flavor SU(3) chiral quark soliton model predicts fairly large particle-antiparticle asymmetry of the strange sea in the nucleon. We point out that the predicted magnitude of asymmetry is large…

High Energy Physics - Phenomenology · Physics 2009-11-10 M. Wakamatsu

The asymmetries of both light-flavor antiquark $\bar{d}(x)-\bar{u}(x)$ and strange-antistrange $s(x)-\bar{s}(x)$ distributions of the nucleon sea are considered with more details in the effective chiral quark model. We find that the…

High Energy Physics - Phenomenology · Physics 2009-11-11 Yong Ding , Rong-Guang Xu , Bo-Qiang Ma

We calculate the strange quark and antiquark distributions of the nucleon by using the effective chiral quark model, and find that the strange-antistrange asymmetry can bring a contribution of about 60--100% to the NuTeV deviation of…

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

Based on the finite-temperature field theory, we evaluate the medium effects in nucleon which can induce an asymmetry between quarks and antiquarks of the strange sea. The short-distance effects determined by the weak interaction can give…

High Energy Physics - Phenomenology · Physics 2009-11-07 Xue-Qian Li , Xiao-Bing Zhang , Bo-Qiang Ma

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 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

The NuTeV collaboration recently reported a value of sin2thetaW measured in neutrino-nucleon scattering that is 3 standard deviations above the standard model prediction. This result is derived assuming that (1) the strange sea is…

High Energy Physics - Experiment · Physics 2014-11-17 NuTeV Collaboration , G. P. Zeller , K. S. McFarland

Precise knowledge of the strange and antistrange quark distributions of the nucleon is a major step toward better understanding of the strong interaction and the nucleon structure. Moreover, the $ s-\bar s $ asymmetry in the nucleon plays…

High Energy Physics - Phenomenology · Physics 2016-02-02 Maral Salajegheh

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

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
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