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arXiv · 1609.04369

Eta-Eta' mixing and the derivative of the topological susceptibility at zero momentum transfer

N. F. Nasrallah
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Abstract

The couplings of the isosinglet axial-vector currents to the Eta and Eta' mesons are evaluated in a stable, model independent way by use of polynomial kernels in dispersion integrals. The corrections to the Gell-Mann-Oakes-Renner relation in the isoscalar channel are deduced. The derivative of the topological susceptibility at the origin is calculated taking into account instantons and instanton screening.

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N. F. Nasrallah. 2016-09-14. Eta-Eta' mixing and the derivative of the topological susceptibility at zero momentum transfer. https://doi.org/10.1103/physrevd.95.033001

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