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Related papers: The Nucleon's Antiquark Sea: A Virtual Meson Cloud…

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We address the question whether the nucleon's antiquark sea can be attributed entirely to its virtual meson cloud and, in essence, whether there exists a smooth transition between hadronic and quark-gluon degrees of freedom. We take into…

High Energy Physics - Phenomenology · Physics 2008-11-26 W. Koepf , L. L. Frankfurt , M. Strikman

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

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

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

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 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

Statistical approach for proton and neutron have been used to study the low energy properties of nucleons. Nucleons is assumed as a composite system of three quarks and "sea" where sea is assumed to be in S-wave consisting of…

High Energy Physics - Phenomenology · Physics 2012-02-01 M. Batra , A. Upadhyay

We have applied the Meson Cloud Model (MCM) to calculate the charm and strange antiquark distribution in the nucleon. The resulting distribution, in the case of charm, is very similar to the intrinsic charm momentum distribution in the…

High Energy Physics - Phenomenology · Physics 2009-10-28 S. Paiva , M. Nielsen , F. S. Navarra , F. O. Durães , L. L. Barz

We present the general formalism required to derive generalized parton distributions within a convolution model where the bare nucleon is dressed by its virtual meson cloud. In the one-meson approximation the Fock states of the physical…

High Energy Physics - Phenomenology · Physics 2008-11-26 B. Pasquini , S. Boffi

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 and antistrange quark distributions of the nucleon are less constrained by experimental data than the non-strange quark sea. The combination of light quark sea distributions, $\Delta(x)=\dbar(x)+\ubar(x)-s(x)-\sbar(x)$,…

High Energy Physics - Phenomenology · Physics 2010-08-26 H. Chen , F. -G. Cao , A. I. Signal

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

We calculate the sea quark distribution of the nucleon in a meson cloud model. The novel feature of our calculation is the implementation of a special piNN form factor recently obtained by Holzwarth and Machleidt. This form factor is hard…

High Energy Physics - Phenomenology · Physics 2008-11-26 R. J. Fries , A. Schaefer

We identify quark and gluon helicity-flip distributions defined between nucleon states of unequal momenta. The evolution of these distributions with change of renormalization scale is calculated in the leading-logarithmic approximation. The…

High Energy Physics - Phenomenology · Physics 2009-10-31 Pervez Hoodbhoy , Xiangdong Ji

We point out that charge symmetry violation in both the valence and sea quark distributions of the nucleon has a non-perturbative source. We calculate this non-perturbative charge symmetry violation using the meson cloud model, which has…

High Energy Physics - Phenomenology · Physics 2009-10-31 Fu-Guang Cao , A. I. Signal

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

We studied the statistical model of nucleons consisting of sea having various quark-gluon Fock states in addition to valence quarks. Using statistical consideration and taking 86% of the total Fock states contributing to the low energy…

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

Using constituent quark model constraints we calculate the gluon and sea-quark content of pions solely in terms of their valence density (fixed by \pi N Drell-Yan data) and the known sea and gluon distributions of the nucleon, using the…

High Energy Physics - Phenomenology · Physics 2010-04-06 M. Gluck , E. Reya , I. Schienbein

Nuclear parton distributions are studied in a parton model with rescaling and recombination mechanisms. Parton x distributions are first calculated at Q^2=1 GeV^2 by the model, and they are evolved to larger Q^2 in order to be compared with…

High Energy Physics - Phenomenology · Physics 2007-05-23 S. Kumano , K. Umekawa

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
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