Further Comments on a Vanishing Singlet Axial Vector Charge
نویسندگان
چکیده
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 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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