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$U_A$(1) Anomaly in Background Fields Dominated by QCD-Monopoles on SU(2) Lattice

Shoichi Sasaki·Osamu Miyamura
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Abstract

We study $U_A$(1) anomaly of non-perturbative QCD in the maximally abelian gauge on SU(2) lattice. The existence of the strong correlation between QCD-monopoles and instantons in the abelian gauge is shown by both analytic and numerical works including lattice simulations. These results bring us a conjecture that the $U_A$(1) symmetry would be explicitly broken in the background fields dominated by QCD-monopoles. We find an evidence for our conjecture by measuring the chiral-asymmetric zero modes of the Dirac operator in the backgrounds of QCD-monopoles.

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Shoichi Sasaki, Osamu Miyamura. 1997-06-13. $U_A$(1) Anomaly in Background Fields Dominated by QCD-Monopoles on SU(2) Lattice. https://arxiv.org/abs/hep-lat/9706001

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