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QCD Sum Rules: Isospin Symmetry Breakings in Pion-Nucleon Couplings

W-Y. P. Hwang·Ze-sen Yang·Y. S. Zhong·Z. N. Zhou·Shi-lin Zhu
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Abstract

We use the method of QCD sum rules in the presence of an external pion field to investigate isospin symmetry breakings in pion-nucleon couplings. Possible manifestations of such isospin symmetry breaking are examined in the context of low-energy nucleon-nucleon ($NN$) scattering. We discuss numerical results in relation to both the existing data and other theoretical predictions.

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W-Y. P. Hwang, Ze-sen Yang, Y. S. Zhong, Z. N. Zhou, Shi-lin Zhu. 1996-10-18. QCD Sum Rules: Isospin Symmetry Breakings in Pion-Nucleon Couplings. https://doi.org/10.1103/physrevc.57.61

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