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Low-energy couplings of QCD from topological zero-mode wave functions

L. Giusti·P. Hernandez·M. Laine·P. Weisz·H. Wittig
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Abstract

By matching 1/m^2 divergences in finite-volume two-point correlation functions of the scalar or pseudoscalar densities with those obtained in chiral perturbation theory, we derive a relation between the Dirac operator zero-mode eigenfunctions at fixed non-trivial topology and the low-energy constants of QCD. We investigate the feasibility of using this relation to extract the pion decay constant, by computing the zero-mode correlation functions on the lattice in the quenched approximation and comparing them with the corresponding expressions in quenched chiral perturbation theory.

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L. Giusti, P. Hernandez, M. Laine, P. Weisz, H. Wittig. 2004-01-28. Low-energy couplings of QCD from topological zero-mode wave functions. https://doi.org/10.1088/1126-6708%2F2004%2F01%2F003

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