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arXiv · hep-ph/9206251

Comments on the Vacuum Orientations in QCD

Zheng Huang·K. S. Viswanathan·D. D. Wu
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Abstract

We study the QCD vacuum orientation angles in correlation with the strong CP phases. A vacuum alignment equation of the dynamical chiral symmetry breaking is derived based on the anomalous Ward identity. It is emphasized that a chiral rotation of the quark field causes a change of the vacuum orientation and a change in the definition of the light pseudoscalar generators. As an illustration of the idea, $\h\rightarrow 2\p$ decays are carefully studied in different chiral frames. Contrary to the claim in Ref.[7], the $θ$-term does not directly contribute to the CP-violating processes.

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Zheng Huang, K. S. Viswanathan, D. D. Wu. 1992-06-25. Comments on the Vacuum Orientations in QCD. https://doi.org/10.1142/s0217732392002524

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