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arXiv · hep-ph/9403380

Pi- Eta Mixing from QCD Sum Rules

Chuan-Tsung Chan·E. M. Henley·Th. Meissner
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Abstract

The $q^2$ dependence of the $π$-$η$ mixing amplitude is examined with the use of QCD sum rules. The linear slope of the mixing function $θ(q^2)$ is found to be much smaller than that for $ρ$-$ω$ mixing. Thus the mixing amplitude is approximately the same in the space-like region as in the time-like one, and one may neglect the $q^2$ dependence of the mixing. A comparison between a hadron-meson, an effective chiral model, and the QCD sum rules approaches is made.

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Chuan-Tsung Chan, E. M. Henley, Th. Meissner. 1994-03-28. Pi- Eta Mixing from QCD Sum Rules. https://doi.org/10.1016/0370-2693(94)01461-k

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