English
Related papers

Related papers: The shape of the nucleon

200 papers

Results for the proton and neutron electric and magnetic form factors as well as the nucleon axial form factor are presented for constituent quark models, based on either one-gluon-exchange and Goldstone-boson-exchange dynamics. The…

High Energy Physics - Phenomenology · Physics 2007-05-23 R. F. Wagenbrunn , S. Boffi , L. Ya. Glozman , W. Klink , W. Plessas , M. Radici

The main statement of the nucleon constituent quark model with a fixed number of particles as basic ansatz are considered in a framework of the single-time (quasipotential) approach to the bound state problem. The scaling law breacking for…

High Energy Physics - Phenomenology · Physics 2007-05-23 T. P. Ilichova , S. G Shulga

We study the nucleon electromagnetic form factors in a quark-gluon core model framework, which can be viewed as an extension of the Isgur-Karl model of baryons. Using this picture we derive nucleon electromagnetic dipole form factors at low…

High Energy Physics - Phenomenology · Physics 2009-12-04 Xian-Qiao Yu

We present a detailed analysis of nucleon electromagnetic and axial form factors in a holographic soft-wall model. This approach is based on an action which describes hadrons with broken conformal invariance and incorporates confinement…

High Energy Physics - Phenomenology · Physics 2012-08-23 Thomas Gutsche , Valery E. Lyubovitskij , Ivan Schmidt , Alfredo Vega

The axial form factor of the nucleon is studied in a two-component model consisting of a three-quark intrinsic structure surrounded by a meson cloud. The experimental data in the space-like region are well reproduced with a minimal number…

Nuclear Theory · Physics 2008-11-26 C. Adamuščín , E. Tomasi-Gustafsson , E. Santopinto , R. Bijker

The nucleon axial vector form factor is investigated in a light-cone quark spectator diquark model, in which Melosh rotations are applied to both the quark and vector diquark. It is found that this model gives a very good description of…

High Energy Physics - Phenomenology · Physics 2009-11-07 Bo-Qiang Ma , Di Qing , Ivan Schmidt

We decompose various quark-gluon Fock states of a nucleon in a set of states in which each of the three-quark core and the rest of the stuff, termed as a sea, appears with definite spin and color quantum number, their weight being…

High Energy Physics - Phenomenology · Physics 2008-11-26 J. P. Singh , Alka Upadhyay

The nucleon elastic form factors are generally interpreted as a mapping of the charge and magnetic current distributions of the proton and neutron. New high Q^2 measurements have opened up fundamental questions about G_ep that remain to be…

High Energy Physics - Experiment · Physics 2009-06-02 R. Bradford , A. Bodek , H. Budd , J. Arrington

The electromagnetic and gravitational form factors of the nucleon determined by quark and gluon contributions are calculated using the momentum transfer dependence of generalized parton distributions with different forms of parton…

High Energy Physics - Phenomenology · Physics 2025-09-16 O. V. Selyugin , O. V. Teryaev

Precise proton and neutron form factor measurements at Jefferson Lab, using spin observables, have recently made a significant contribution to the unraveling of the internal structure of the nucleon. Accurate experimental measurements of…

Nuclear Experiment · Physics 2015-06-02 V. Punjabi , C. F. Perdrisat , M. K. Jones , E. J. Brash , C. E. Carlson

The electromagnetic form factors of nucleons are calculated using an AdS/QCD model by considering a Dirac field coupled to a vector field in the 5-dimensional AdS space. We also calculate a gravitational or energy-momentum form factor by…

High Energy Physics - Phenomenology · Physics 2009-06-30 Zainul Abidin , Carl E. Carlson

Results for the proton and neutron electric and magnetic form factors as well asthe nucleon axial and induced pseudoscalar form factors are presented for the chiral constituent quark model based on Goldstone-boson-exchange dynamics. The…

High Energy Physics - Phenomenology · Physics 2007-05-23 S. Boffi , L. Ya. Glozman , W. Klink , W. Plessas , M. Radici , R. F. Wagenbrunn

The strange form factors of the nucleon are studied in a two-component model consisting of a three-quark intrinsic structure surrounded by a meson cloud. A comparison with the available experimental world data from the SAMPLE, PVA4, HAPPEX…

Nuclear Theory · Physics 2008-11-26 R. Bijker

We investigate the possible modifications of the nucleons' electromagnetic form factors in the framework of a modified Skyrme model allowing for nucleon deformation and using realistic nuclear mass distributions. We show that such effects…

Nuclear Theory · Physics 2007-05-23 Ulughbek T. Yakhshiev , Ulf-G. Meißner , Andreas Wirzba

We define a constituent quark within QCD. It is shown that the spin of such a quark and hence also the spin of the nucleon reduced due to $\bar{q}q$-pairs, in agreement with experiment. A solution to the spin problem is given.

High Energy Physics - Phenomenology · Physics 2009-01-07 Harald Fritzsch

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 2007-05-23 M. A. Ivanov , M. P. Locher , V. E. Lyubovitskij

The nucleon form factors provide fundamental knowledge about the strong interaction. We review the flavor composition of the nucleon form factors and focus on an analysis of the possible impact of the s-quark contribution. A future…

Nuclear Experiment · Physics 2020-01-08 Bogdan Wojtsekhowski

In a model where constituent quarks and diquarks interact through quark exchange the Bethe-Salpeter equation in ladder approximation for the nucleon is solved. Quark and diquark confinement is effectively parametrized by choosing…

High Energy Physics - Phenomenology · Physics 2016-09-06 G. Hellstern. R. Alkofer , M. Oettel , H. Reinhardt

In this paper we present the derivation as well as the numerical results for the electromagnetic form factors of the nucleon within the chiral quark soliton model in the semiclassical quantization scheme. The model is based on semibosonized…

High Energy Physics - Phenomenology · Physics 2009-10-28 Chr. V. Christov , A. Z. Górski , K. Goeke , P. V. Pobylitsa

We analyze the electromagnetic form factors of the nucleon to fourth order in relativistic baryon chiral perturbation theory. We employ the recently proposed infrared regularization scheme and show that the convergence of the chiral…

High Energy Physics - Phenomenology · Physics 2009-10-31 Bastian Kubis , Ulf-G. Meißner