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Related papers: The shape of the nucleon

200 papers

We apply the perturbative chiral quark model at one loop to calculate the strange form factors of the nucleon. A detailed numerical analysis of the strange magnetic moments and radii of the nucleon, and also the momentum dependence of the…

High Energy Physics - Phenomenology · Physics 2009-11-07 V. E. Lyubovitskij , P. Wang , Th. Gutsche , Amand Faessler

The nucleon form factors of the energy-momentum tensor are studied in the large-Nc limit in the framework of the chiral quark-soliton model.

High Energy Physics - Phenomenology · Physics 2008-11-26 K. Goeke , J. Grabis , J. Ossmann , M. V. Polyakov , P. Schweitzer , A. Silva , D. Urbano

New results about the electromagnetic form factors of the nucleon are obtained with a semirelativistic version of the hypercentral constituent quark model (hCQM) and a relativistic current. The complex structure of the constituent quarks is…

Nuclear Theory · Physics 2015-07-21 M. De Sanctis , M. M. Giannini , E. Santopinto , A. Vassallo

The covariant quark model is shown to allow a phenomenological description of the neutron electric form factor, G_E^n(Q^2), in the impulse approximation, provided that the wave function contains minor (~ 3 %) admixtures of the lowest…

Nuclear Theory · Physics 2008-11-26 Q. B. Li , D. O. Riska

The three-dimensional spatial structure of hadrons is encoded in their form factors. Via appropriate Fourier transform, the latter describe how charge, energy, linear and angular momentum, but also pressure are distributed inside these…

High Energy Physics - Phenomenology · Physics 2024-07-16 Cédric Lorcé

This review focuses on the current status of lattice calculations of three observables which are both phenomenologically and experimentally relevant and have been scrutinized recently. These three observables are the nucleon electromagnetic…

High Energy Physics - Lattice · Physics 2009-11-11 Wolfram Schroers

We develop a formally covariant quark-diquark model of the nucleon. The nucleon is treated as a bound state of a constituent quark and a diquark interacting via a quark exchange. We include both scalar and axial-vector diquarks. The…

Nuclear Theory · Physics 2007-05-23 Volker Keiner

I discuss a two-component model of nucleon form factors in which the external photon couples both to an intrinsic three-quark structure and to a meson cloud via vector-meson dominance, and present a simultaneous analysis of the…

Nuclear Theory · Physics 2008-11-26 Roelof Bijker

The comparison of magnetic moments of neutron and proton reveals three possible states of a nucleon. The arguments are presented why these states can be the stationary states.

Nuclear Theory · Physics 2007-05-23 A. V. Kopylov

The meson-cloud model of the nucleon consisting of a system of three valence quarks surrounded by a meson cloud is applied to study the electroweak structure of the proton and neutron. The electroweak nucleon form factors are calculated…

High Energy Physics - Phenomenology · Physics 2015-05-13 B. Pasquini , S. Boffi

We compute the electromagnetic form factors of the nucleon in the Poincare-covariant Faddeev framework based on the Dyson-Schwinger equations of QCD. The general expression for a baryon's electromagnetic current in terms of three…

High Energy Physics - Phenomenology · Physics 2011-08-08 Gernot Eichmann

An approach for a unified description of the nucleon electromagnetic form factors in spacelike and timelike regions is presented. The main ingredients of our model are: $i)$ a Mandelstam formula for the matrix elements of the nucleon…

High Energy Physics - Phenomenology · Physics 2017-08-23 J. P. B. C. de Melo , T. Frederico , E. Pace , S. Pisano , G. Salme`

Nucleon, pion and quark form factors are studied within the relativistic harmonic oscillator model including the quark spin. It is shown that the nucleon charge, magnetic and axial form factors and the pion charge form factor can be…

High Energy Physics - Phenomenology · Physics 2010-12-17 V. V. Burov , A. De Pace , S. M. Dorkin , P. Saracco

Moments of unpolarized, helicity, and transversity distributions, electromagnetic form factors, and generalized form factors of the nucleon are presented from a preliminary analysis of lattice results using pion masses down to 359 MeV. The…

High Energy Physics - Lattice · Physics 2014-11-17 R. G. Edwards , G. Fleming , Ph. Hagler , J. W. Negele , K. Orginos , A. V. Pochinsky , D. B. Renner , D. G. Richards , W. Schroers

We demonstrate that a relativistic constituent quark model can give nucleon form factors that agree well with recent, accurate measurements. The relativistic features of the model and the specific form of the wave function are essential for…

High Energy Physics - Phenomenology · Physics 2009-09-25 Felix Schlumpf

The electromagnetic and axial form factors of the nucleon and its lowest positive parity excitations, the Delta(1232) and the N*(1440), are calculated with constituent-quark models that are specified by simple algebraic representations of…

High Energy Physics - Phenomenology · Physics 2014-11-17 B. Julia-Diaz , D. O. Riska , F. Coester

We report the calculation of electromagnetic form factors of nucleons within a relativistic three-quark model with Gaussian shape for the nucleon-quark vertex. The allowed region for two adjustable parameters, the range parameter…

High Energy Physics - Phenomenology · Physics 2008-11-26 M. A. Ivanov , M. P. Locher , V. E. Lyubovitskij

The use of relativistic quark models with simple parametric wave functions for the understanding of the electromagnetic structure of nucleons together with their electromagnetic transition to resonances is discussed. The implications of…

Nuclear Theory · Physics 2008-11-26 B. Julia-Diaz

We review a recent theoretical determination of the strange quark content of the electromagnetic form factors of the nucleon. These are compared with a global analysis of current experimental measurements in parity-violating electron…

Nuclear Theory · Physics 2008-11-26 Ross D. Young

A symmetry-preserving analysis of strong interaction quantum field equations is used to complete a unified treatment of pion, kaon, nucleon electromagnetic and gravitational form factors. Findings include a demonstration that the pion…

High Energy Physics - Phenomenology · Physics 2024-10-10 Z. -Q. Yao , Y. -Z. Xu , D. Binosi , Z. -F. Cui , M. Ding , K. Raya , C. D. Roberts , J. Rodríguez-Quintero , S. M. Schmidt