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arXiv · 1711.00729

Electromagnetic and Axial-Vector Form Factors of the Quarks and Nucleon

Abstract

In light of the improved precision of the experimental measurements and enormous theoretical progress, the nucleon form factors have been evaluated with an aim to understand how the static properties and dynamical behavior of nucleons emerge from the theory of strong interactions between quarks. We have analysed the vector and axial-vector nucleon form factors ($G^{p,n}_{E,M}(Q^2)$ and $G^{p,n}_{A}(Q^2)$) using the spin observables in the chiral constituent quark model ($\chi$CQM) which has made a significant contribution to the unraveling of the internal structure of the nucleon in the nonperturbative regime. We have also presented a comprehensive analysis of the flavor decomposition of the form factors ($G^{q}_{E}(Q^2)$, $G^{q}_{M}(Q^2)$ and $G^{q}_{A}(Q^2)$for $q=u,d,s$) within the framework of $\chi$CQM with emphasis on the extraction of the strangeness form factors which are fundamental to determine the spin structure and test the chiral symmetry breaking effects in the nucleon. The $Q^2$ dependence of the vector and axial-vector form factors of the nucleon has been studied using the conventional dipole form of parametrization. The results are in agreement with the available experimental data.

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Harleen Dahiya, Monika Randhawa. 2017-11-01. Electromagnetic and Axial-Vector Form Factors of the Quarks and Nucleon. https://doi.org/10.1142/s0217751x17501858

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