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arXiv · hep-lat/0211020

Finite-Size Scaling of Vector and Axial Current Correlators

P. H. Damgaard·P. Hernandez·K. Jansen·M. Laine·L. Lellouch
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Abstract

Using quenched chiral perturbation theory, we compute the long-distance behaviour of two-point functions of flavour non-singlet axial and vector currents in a finite volume, for small quark masses, and at a fixed gauge-field topology. We also present the corresponding predictions for the unquenched theory at fixed topology. These results can in principle be used to measure the low-energy constants of the chiral Lagrangian, from lattice simulations in volumes much smaller than one pion Compton wavelength. We show that quenching has a dramatic effect on the vector correlator, which is argued to vanish to all orders, while the axial correlator appears to be a robust observable only moderately sensitive to quenching.

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P. H. Damgaard, P. Hernandez, K. Jansen, M. Laine, L. Lellouch. 2003-02-13. Finite-Size Scaling of Vector and Axial Current Correlators. https://doi.org/10.1016/s0550-3213(03)00117-2

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