Nucleon structure functions and longitudinal spin asymmetries in the chiral quark constituent model

Abstract

We have analysed the phenomenological dependence of the spin independent ($F_1^{p,n}$ and $F_2^{p,n}$) and the spin dependent ($g_1^{p,n}$) structure functions of the nucleon on the the Bjorken scaling variable $x$ using the unpolarized distribution functions of the quarks $q(x)$ and the polarized distribution functions of the quarks $\Delta q(x)$ respectively. The chiral constituent quark model ($\chi$CQM), which is known to provide a satisfactory explanation of the proton spin crisis and related issues in the nonperturbative regime, has been used to compute explicitly the valence and sea quark flavor distribution functions of $p$ and $n$. In light of the improved precision of the world data, the $p$ and $n$ longitudinal spin asymmetries ($A_1^p(x)$ and $A_1^n(x)$) have been calculated. The implication of the presence of the sea quarks has been discussed for ratio of polarized to unpolarized quark distribution functions for up and down quarks in the $p$ and $n$ $\frac{\Delta u^p(x)}{u^p(x)}$, $\frac{\Delta d^p(x)}{d^p(x)}$, $\frac{\Delta u^n(x)}{u^n(x)}$, and $\frac{\Delta d^n(x)}{d^n(x)}$. The ratio of the $n$ and $p$ structure functions $R^{np}(x)=\frac{F_2^n(x)}{F_2^p(x)}$ has also been presented. The results have been compared with the recent available experimental observations. The results on the spin sum rule have also been included and compared with data and other recent approaches.

28 pages, 8 figures. To appear in PRD. arXiv admin note: text overlap with arXiv:1505.03304

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Cited by in corpus (8)

• The Spin Structure of the Nucleon
• Magnetic Moments of Octet Baryons in Hot and Dense Nuclear Matter
• Study of spin-dependent structure functions of ${}^3\mathrm{He}$ and ${}^3\mathrm{H}$ at NNLO approximation and corresponding nuclear corrections
• Transition magnetic moments of $J^P={\frac{3}{2}}^{+}$ decuplet to $J^P={\frac{1}{2}}^{+}$ octet baryons in the chiral constituent quark model
• Phenomenology of leading nucleon production in $ep$ collisions at HERA in the framework of fracture functions
• Determination of neutron fracture functions from a global QCD analysis of leading neutron production at HERA
• Electromagnetic and Axial-Vector Form Factors of the Quarks and Nucleon
• Parton distribution functions with QED corrections in the valon model