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arXiv · 1401.7420

Quark tensor and axial charges within the Schwinger-Dyson formalism

Abstract

We calculate the tensor and axial charges of the quark in the Schwinger-Dyson formalism of Landau gauge QCD. It is found that the dressed tensor and isovector axial charges of the quark are suppressed against the bare quark contribution, and the result agrees qualitatively with the experimental data. We show that this is due to the superposition of the spin flip of the quark arising from the successive emission of gluons which dress the vertex. For the isoscalar quark axial charge, we have analyzed the Schwinger-Dyson equation by including the leading unquenching quark-loop effect. It is found that the suppression is more significant, due to the axial anomaly effect.

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Nodoka Yamanaka, Takahiro M. Doi, Shotaro Imai, Hideo Suganuma. 2014-01-29. Quark tensor and axial charges within the Schwinger-Dyson formalism. https://arxiv.org/abs/1401.7420

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