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arXiv · hep-ph/9501245

Instantons and Meson Correlators in QCD

Marcus Hutter
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Abstract

Various QCD correlators are calculated in the instanton liquid model in zeromode approximation and $1/N_c$ expansion. Previous works are extended by including dynamical quark loops. In contrast to the original "perturbative" $1/N_c$ expansion not all quark loops are suppressed. In the flavor singlet meson correlators a chain of quark bubbles survives the $N_c\to\infty$ limit causing a massive $η^\prime$ in the pseudoscalar correlator while keeping massless pions in the triplet correlator. The correlators are plotted and meson masses and couplings are obtained from a spectral fit. They are compared to the values obtained from numerical studies of the instanton liquid and to experimental results.

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Marcus Hutter. 1995-01-09. Instantons and Meson Correlators in QCD. https://doi.org/10.1007/s002880050376

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