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Related papers: Electromagnetic proton form factors in large $N_{c…

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Electron scattering at large Q^2 probes a nucleon's quark core. This core's contribution to electromagnetic form factors may be calculated using Poincare' covariant Faddeev amplitudes combined with a nucleon-photon vertex that automatically…

Nuclear Theory · Physics 2008-11-26 A Hoell , R. Alkofer , M. Kloker , A. Krassnigg , C. D. Roberts , S. V. Wright

In this talk, recent results are presented of calculations of electromagnetic form factors of hadrons in the framework of two quantum field theories (QFT), (a) Dual-Large $N_c$ QCD (Dual-$QCD_\infty$) for the pion, proton, and…

High Energy Physics - Phenomenology · Physics 2008-11-26 C. A. Dominguez

The pion electromagnetic form factor is investigated by using the dispersion relation with the superconvergence condition, which was proposed to synthesize the vector meson dominance model and QCD. The absorptive part is given as an…

High Energy Physics - Phenomenology · Physics 2007-05-23 Keiji Watanabe , Hirohisa Ishikawa , Masami Nakagawa

We derive the electric and magnetic form factors of the neutron in the framework of a relativistic constituent quark model. Our parameter free prediction agrees well with a recent, accurate measurement. The relativistic features of the…

High Energy Physics - Phenomenology · Physics 2015-06-25 Felix Schlumpf

We discuss the recent experimental results on the ratio bertween the electric and magnetic proton form factors and how they can be described by the hypercentral Constituent Quark Model.

Nuclear Theory · Physics 2015-06-30 M. De Sanctis , M. M. Giannini , E. Santopinto , A. Vassallo

The electromagnetic form factors are crucial to our understanding of the proton internal structure, and thus provide a strong constraint of the distributions of the charge and magnetization current within the proton. We adopted the…

High Energy Physics - Phenomenology · Physics 2007-05-23 M Y Hussein

We obtain the electromagnetic form factors of the $\gamma N\Delta$ transition by analyzing recent pion-electroproduction data using a fully relativistic dynamical model. Special care is taken to satisfy Ward-Takahashi identities for the…

Nuclear Theory · Physics 2010-01-18 G. L. Caia , V. Pascalutsa , J. A. Tjon , L. E. Wright

By means of the 10-resonance unitary and analytic model of nucleon electromagnetic structure it is demonstrated that the JLab proton polarization data on the ratio $\mu_p G_{Ep}(Q^2)/G_{Mp}(Q^2)$ are consistent with all form factor…

High Energy Physics - Phenomenology · Physics 2007-08-02 A. Z. Dubnickova , S. Dubnicka

We analyse various $U(1)_{EM}$ form factors of mesons at strong coupling in an $\mathcal{N}=2$ flavored version of $\mathcal{N}=4$ $SYM$ which becomes conformal in the UV. The quark mass breaks the conformal symmetry in the IR and generates…

High Energy Physics - Theory · Physics 2008-11-26 D. Rodriguez-Gomez , J. Ward

There has been much activity in the measurement of the elastic electromagnetic proton and neutron form factors in the last decade, and the quality of the data has been greatly improved by performing double polarization experiments, in…

High Energy Physics - Phenomenology · Physics 2009-09-29 C. F. Perdrisat , V. Punjabi , M. Vanderhaeghen

In treating the relativistic three-quark problem, a dressed-quark propagator parameterization is used which is compatible with recent lattice data and pion observables. Furthermore two-quark correlations are modeled as a series of quark…

High Energy Physics - Phenomenology · Physics 2008-11-26 M. Oettel , R. Alkofer

We calculate electromagnetic form factors of the proton bound in specified orbits for several closed shell nuclei. The quark structure of the nucleon and the shell structure of the finite nuclei are given by the QMC model. We find that…

Nuclear Theory · Physics 2010-02-17 D. H. Lu , K. Tsushima , A. W. Thomas , A. G. Williams , K. Saito

There is a long-standing discrepancy between different measurements of the electric and magnetic radii of the proton. Lattice QCD calculations are a well-suited tool for theoretical investigations of the structure of the nucleon from first…

High Energy Physics - Lattice · Physics 2024-05-24 Dalibor Djukanovic , Georg von Hippel , Harvey B. Meyer , Konstantin Ottnad , Miguel Salg , Hartmut Wittig

Dispersion relations allow for a coherent description of the nucleon electromagnetic form factors measured over a large range of momentum transfer, $Q^2 \simeq 0 \ldots 35$ GeV$^2$. Including constraints from unitarity and perturbative QCD,…

High Energy Physics - Phenomenology · Physics 2008-11-26 P. Mergell , Ulf-G. Meißner , D. Drechsel

We study the nucleon electromagnetic (EM) form factors in symmetric nuclear matter as well as in vacuum within a light-front approach using the in-medium inputs calculated by the quark-meson coupling model. The same in-medium quark…

High Energy Physics - Phenomenology · Physics 2018-03-14 W. R. B. de Aráujo , J. P. B. C. de Melo , K. Tsushima

We present a detailed study of the nucleon electromagnetic form factors in the spacelike region by combining three complementary approaches: two GPD-based contributions and a vector-meson exchange component. By fitting experimental data, we…

High Energy Physics - Phenomenology · Physics 2026-04-13 Hossein Vaziri , Mohammad Reza Shojaei , Pere Masjuan

Nucleon electromagnetic form factors are fundamental quantities related to the charge and magnetization distributions inside the nucleon. Understanding the nucleon electromagnetic structure in terms of the underlying quark and gluon degrees…

Nuclear Experiment · Physics 2008-11-26 Haiyan Gao

The electromagnetic N-$\Delta$ transition form factors are calculated in the framework of a formally covariant constituent diquark model. As a spin-3/2 particle the $\Delta$ is assumed to be a bound state of a quark and an axial-vector…

Nuclear Theory · Physics 2011-07-19 Volker Keiner

Among the most fundamental observables of nucleon structure, electromagnetic form factors are a crucial benchmark for modern calculations describing the strong interaction dynamics of the nucleon's quark constituents; indeed, recent proton…

Based on the recent, high precision data for elastic electron scattering from protons and deuterons, at relatively large momentum transfer $Q^2$, we determine the neutron electric form factor up to $Q^2=3.5$ GeV$^2$. The values obtained…

Nuclear Theory · Physics 2009-11-07 Egle Tomasi-Gustafsson , Michail P. Rekalo