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arXiv · hep-ph/9712351

New Relations and Constraints on Quark Spin-flavor Contents in Symmetry-breaking Chiral Quark Model

X. Song
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Abstract

New relations between the quark spin-flavor contents of the nucleon and axial weak coupling constants are obtained in the chiral quark model with both SU(3) and U(1)-breaking effects. Using the nonsinglet spin combinations, $Δ_3$ and $Δ_8$, all spin-flavor observables are functions of only one parameter $a$ $-$ probability for the chiral pionic fluctuation. The upper and lower bounds of these observables are given. The optimal range of $a$, determined by NMC data $\bar d-\bar u$, gives a constraint to the cutoff of the chiral quark field theory. The model predictions are in good agreement with the existing data in this range of $a$. The roles of kaon, $η$ and $η'$ are also discussed.

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X. Song. 1997-12-11. New Relations and Constraints on Quark Spin-flavor Contents in Symmetry-breaking Chiral Quark Model. https://doi.org/10.1103/physrevd.57.4114

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