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arXiv · hep-ph/9511424

Nucleon Spin and the Mixing of Axial Vector Mesons

Michael Birkel·Harald Fritzsch
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Abstract

It is shown that the QCD anomaly may lead to an abnormal mixing behavior of the axial vector mesons similar to the pseudoscalar mesons. These mixing effects, involving a gluonic axial vector state, generate a non-vanishing strange quark component in the nucleon. They reduce the matrix element of the singlet axial vector in comparison to the value obtained in a naive quark model. The results are in agreement with the data obtained in the polarized lepton-nucleon scattering experiments.

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Michael Birkel, Harald Fritzsch. 1996-06-12. Nucleon Spin and the Mixing of Axial Vector Mesons. https://doi.org/10.1103/physrevd.53.6195

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