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arXiv · 0912.2687

Vacuum pseudoscalar susceptibility

Lei Chang·Yu-Xin Liu·Craig D. Roberts·Yuan-Mei Shi·Wei-Min Sun·Hong-Shi Zong
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Abstract

We derive a novel model-independent result for the pion susceptibility in QCD via the isovector-pseudoscalar vacuum polarisation. In the neighbourhood of the chiral-limit, the pion susceptibility can be expressed as a sum of two independent terms. The first expresses the pion-pole contribution. The second is identical to the vacuum chiral susceptibility, which describes the response of QCD's ground-state to a fluctuation in the current-quark mass. In this result one finds a straightforward explanation of a mismatch between extant estimates of the pion susceptibility.

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Lei Chang, Yu-Xin Liu, Craig D. Roberts, Yuan-Mei Shi, Wei-Min Sun, Hong-Shi Zong. 2009-12-14. Vacuum pseudoscalar susceptibility. https://doi.org/10.1103/physrevc.81.032201

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