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arXiv · 1002.2999

The $η$ and $η^\prime$ mesons from Lattice QCD

N. H. Christ·C. Dawson·T. Izubuchi·C. Jung·Q. Liu·R. D. Mawhinney·C. T. Sachrajda·A. Soni·R. Zhou
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Abstract

The large mass of the ninth pseudoscalar meson, the $η^\prime$, is believed to arise from the combined effects of the axial anomaly and the gauge field topology present in QCD. We report a realistic, 2+1 flavor, lattice QCD calculation of the $η$ and $η^\prime$ masses and mixing which confirms this picture. The physical eigenstates show small octet-singlet mixing with a mixing angle of $θ= -14.1(2.8)^\circ$. Extrapolation to physical light quark mass gives, with statistical errors only, $m_η=573(6)$ MeV and $m_{η^\prime}=947(142)$ MeV, consistent with the experimental values of 548 MeV and 958 MeV.

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N. H. Christ, C. Dawson, T. Izubuchi, C. Jung, Q. Liu, R. D. Mawhinney, C. T. Sachrajda, A. Soni, R. Zhou. 2010-10-20. The $η$ and $η^\prime$ mesons from Lattice QCD. https://doi.org/10.1103/physrevlett.105.241601

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