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arXiv · 0810.2845

Revisiting the Vector and Axial-vector Vacuum Susceptibilities

Lei Chang·Yu-xin Liu·Wei-min Sun·Hong-shi Zong
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Abstract

We re-investigate the vector and axial-vector vacuum susceptibilities by taking advantage of the vector and axial-vector Ward-Takahashi identities. We show analytically that, in the chiral limit, the vector vacuum susceptibility is zero and the axial-vector vacuum susceptibility equals three fourths of the square of the pion decay constant. Besides, our analysis reproduces the Weinberg sum rule.

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Lei Chang, Yu-xin Liu, Wei-min Sun, Hong-shi Zong. 2008-10-16. Revisiting the Vector and Axial-vector Vacuum Susceptibilities. https://doi.org/10.1016/j.physletb.2008.10.010

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