Nucleon spin and the mixing of axial vector mesons.
نویسندگان
چکیده
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 na¨ıve quark model. The results are in agreement with the data obtained in the polarized lepton–nucleon scattering experiments.
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عنوان ژورنال:
- Physical review. D, Particles and fields
دوره 53 11 شماره
صفحات -
تاریخ انتشار 1996