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arXiv · hep-ph/9610418

A test of the instanton vacuum chiral quark model with axial anomaly low-energy theorems

M. M. Musakhanov·F. C. Khanna
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Abstract

The QCD + QED axial anomaly low-energy theorems are applied to estimate the accuracy of an instanton vacuum - based chiral quark model. The low-energy theorems give an exact relation between the matrix elements of the gluon and photon parts of the QCD + QED axial anomaly operator equation. The matrix elements between vacuum and two photon states and between vacuum and two gluon states are calculated for arbitrary N_f. It is shown that this model does satisfy the low-energy theorems with an accuracy of $\sim 17%$. We estimate also the contribution of the nonperturbative conversion of gluons into photons to the decay $η' \rightarrow 2 γ$ and compare with experimental data.

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M. M. Musakhanov, F. C. Khanna. 1996-11-18. A test of the instanton vacuum chiral quark model with axial anomaly low-energy theorems. https://doi.org/10.1016/s0370-2693(97)00052-x

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