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arXiv · hep-lat/0202001

Witten-Veneziano Relation, Quenched QCD, and Overlap Fermions

Thomas DeGrand·Urs M. Heller
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Abstract

The quarks in quenched QCD have an anomalous self-interaction in the flavor singlet Goldstone boson channel. This coupling is extracted from a graph with disconnected quark lines, and is used to infer the mass of the eta-prime meson in full QCD. When the fermions are described by an overlap action, the Witten-Veneziano relation is an exact relation between the topological susceptibility (as defined through fermionic zero modes) and the inferred value of the eta-prime mass. Using an overlap action we compute the hairpin amplitude and determine the fermion zero-mode susceptibility, the inferred eta-prime mass and other parameters characterizing the low energy chiral properties of quenched QCD.

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Thomas DeGrand, Urs M. Heller. 2002-05-20. Witten-Veneziano Relation, Quenched QCD, and Overlap Fermions. https://doi.org/10.1103/physrevd.65.114501

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