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

M. M. Musakhanov·Hyun-Chul Kim
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Abstract

We revisit the QCD+QED axial anomaly low-energy theorems which give an exact relation between the matrix elements of the gluon and photon parts of the axial anomaly operator equation within the framework of the {\em effective action} derived from the instanton vacuum. The matrix elements between the vacuum and two photon states and between the vacuum and two gluon states are investigated for arbitrary $N_f $ in the chiral limit. Having gauged the effective action properly, we show that the model does exactly satisfy the low-energy theorems.

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M. M. Musakhanov, Hyun-Chul Kim. 2003-07-30. A test of the instanton vacuum with low-energy theorems of the axial anomaly. https://doi.org/10.1016/j.physletb.2003.08.022

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