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arXiv · hep-ph/9812438

Further Comments on a Vanishing Singlet Axial Vector Charge

T. P. Cheng·N. I. Kochelev·V. Vento
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Abstract

The recent suggestion of a vanishing flavor-singlet axial charge of nucleon due to a nontrivial vacuum structure is further amplified. A perturbative QCD discussion, applicable for the heavy quark contributions, relates it to the physics of the decoupling theorem. It is also shown that $g_{A}^{0}\simeq 0$ leads to a negative $η'$-meson-quark coupling, which has been found to be compatible with the chiral quark model phenomenology.

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T. P. Cheng, N. I. Kochelev, V. Vento. 1998-12-18. Further Comments on a Vanishing Singlet Axial Vector Charge. https://doi.org/10.1142/s0217732399000249

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