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arXiv · hep-ph/0606208

Isospin symmetry breaking of K and K* mesons

Hua-Xing Chen·Atsushi Hosaka·Shi-Lin Zhu
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Abstract

We use the method of QCD sum rules to investigate the isospin symmetry breaking of K and K* mesons. The electromagnetic effect, difference between up and down current-quark masses and difference between up and down quark condensates are important. We perform sum rule analyses of their masses and decay constant differences, which are consistent with experimental values. Our results yield Delta f_K = f_{K^0} - f_{K^\pm} = 1.5 MeV.

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Hua-Xing Chen, Atsushi Hosaka, Shi-Lin Zhu. 2006-07-21. Isospin symmetry breaking of K and K* mesons. https://doi.org/10.1103/physrevd.74.033007

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