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We produce the light-front wave functions (LFWFs) of the nucleon from a basis light-front ap- proach in the leading Fock sector representation. We solve for the mass eigenstates from a light-front effective Hamiltonian, which includes a…

High Energy Physics - Phenomenology · Physics 2021-12-08 Siqi Xu , Chandan Mondal , Jiangshan Lan , Xingbo Zhao , Yang Li , James P. Vary

We present a simultaneous analysis of elastic and transition form factors of the nucleon. The calculations are performed in the framework of an algebraic model of baryons. Effects of meson cloud couplings are considered.

Nuclear Theory · Physics 2007-05-23 R. Bijker , A. Leviatan

We treat baryons as bound states of scalar or axialvector diquarks and a constituent quark which interact through quark exchange. This description results as an approximation to the relativistic Faddeev equation for three quarks which…

Nuclear Theory · Physics 2009-10-31 M. Oettel , S. Ahlig , R. Alkofer , C. Fischer

Photoexcitation of the nucleon is studied in the framework of the constituent quark model with nonrelativistic quark-quark interactions. Utilizing the dominance of the pairwise structure of the relevant three-quark potential, the bound and…

Nuclear Theory · Physics 2022-03-02 I. P. Matamba , M. Braun , S. A. Sofianos

We have applied isovector and isoscalar tensor current to evaluate the tensor form factors of the $ N(1535) \rightarrow N $ transition with the help of the light-cone QCD sum rule method. In numerical computations, have used the most…

High Energy Physics - Phenomenology · Physics 2020-07-08 Ulaş Özdem

Using the most general form of the baryon current, nucleon form factors, induced by isovector and isoscalar axial-vector currents, are studied in the framework of light cone QCD sum rule approach. Comparison of our results on form factors…

High Energy Physics - Phenomenology · Physics 2008-11-26 T. M. Aliev , M. Savci

Dispersion relations provide a powerful tool to analyse the electromagnetic form factors of the nucleon both in the space-like and time-like regions with constraints from other experiments, unitarity, and perturbative QCD. We give a brief…

High Energy Physics - Phenomenology · Physics 2007-05-23 H. -W. Hammer

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

The electromagnetic form factors of the nucleon, in the space-like region, are determined from three-point function Finite Energy QCD Sum Rules. The QCD calculation is performed to leading order in perturbation theory in the chiral limit,…

High Energy Physics - Phenomenology · Physics 2009-11-10 H. Castillo , C. A. Dominguez , M. Loewe

The electromagnetic excitation of the nucleon resonances is studied in the framework of Constituent Quark Models. Particular attention is devoted to the transition to the $\Delta$ resonance and to the issue of a possible deformation of…

Nuclear Theory · Physics 2015-06-22 M. M. Giannini

The nucleon-nucleon ($NN$) potential is the residual interaction of the strong interaction in the low-energy region and is also the fundamental input to the study of atomic nuclei. Based on the non-perturbative properties of the quantum…

Nuclear Theory · Physics 2024-10-02 Ke Nan , Jinniu Hu , Hong Shen , Ying Zhang

We determine the generalized form factors, which correspond to the second Mellin moment (i.e., the first $x$-moment) of the generalized parton distributions of the nucleon at leading twist. The results are obtained using lattice QCD with…

High Energy Physics - Lattice · Physics 2019-07-30 Gunnar S. Bali , Sara Collins , Meinulf Göckeler , Rudolf Rödl , Andreas Schäfer , André Sternbeck

We discuss the electromagnetic form factors, axial form factors, and structure functions of a bound nucleon in the quark-meson coupling (QMC) model. Free space nucleon form factors are calculated using the improved cloudy bag model (ICBM).…

Nuclear Theory · Physics 2007-05-23 K. Tsushima , D. H. Lu , W. Melnitchouk , K. Saito , A. W. Thomas

Lattice simulations of QCD have produced precise estimates for the masses of the lowest-lying hadrons which show excellent agreement with experiment. By contrast, lattice results for the vector and axial vector form factors of the nucleon…

High Energy Physics - Lattice · Physics 2011-09-23 B. B. Brandt , S. Capitani , M. Della Morte , D. Djukanovic , J. Gegelia , G. von Hippel , A. Juttner , B. Knippschild , H. B. Meyer , H. Wittig

The proton's elastic electromagnetic form factors are calculated using an Ansatz for the nucleon's Poincare' covariant Faddeev amplitude that only retains scalar diquark correlations. A spectator approximation is employed for the current.…

Nuclear Theory · Physics 2009-01-14 J. C. R. Bloch , A. Krassnigg , C. D. Roberts

Nucleon form factors are calculated in a relativistic diquark--quark picture based on the Nambu--Jona-Lasinio model. The nucleon wave function is obtained in a static approximation to the quark exchange interaction between the valence quark…

High Energy Physics - Phenomenology · Physics 2016-09-01 G. Hellstern , C. Weiss

We review the present situation with hadron form factors in space-like and time-like regions. The possibility to transfer high momenta, and therefore to access small internal nucleon distances, allows to test nucleon models in particular…

High Energy Physics - Phenomenology · Physics 2010-09-24 E. ~Tomasi-Gustafsson

In Poincar\'e-covariant continuum treatments of the three valence-quark bound-state problem, the force behind dynamical chiral symmetry breaking also generates nonpointlike, interacting diquark correlations in the nucleon and its…

Nuclear Theory · Physics 2016-11-09 Jorge Segovia , Craig D. Roberts

The $\gamma^{(\ast)}+p \to N(1535) \tfrac{1}{2}^-$ transition is studied using a symmetry-preserving regularisation of a vector$\,\otimes\,$vector contact interaction (SCI). The framework employs a Poincar\'e-covariant Faddeev equation to…

High Energy Physics - Phenomenology · Physics 2021-12-17 Khépani Raya , L. X. Gutiérrez-Guerrero , Adnan Bashir , Lei Chang , Zhu-Fang Cui , Ya Lu , Craig D. Roberts , Jorge Segovia

We evaluate the nucleon axial form factor, $G_A(q^2)$, and induced pseudoscalar form factor, $G_p(q^2)$, as well as the pion-nucleon form factor, $G_{\pi N N}(q^2)$, in lattice QCD. We also evaluate the corresponding nucleon to $\Delta$…

High Energy Physics - Lattice · Physics 2014-11-18 C. Alexandrou , G. Koutsou , Th. Leontiou , J. W. Negele , A. Tsapalis