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arXiv · hep-lat/9305025

Nucleon Axial Form Factor from Lattice QCD

K. F. Liu·S. J. Dong·T. Draper·J. M. Wu·W. Wilcox
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Abstract

Results for the isovector axial form factors of the proton from a lattice QCD calculation are presented for both point-split and local currents. They are obtained on a quenched $16^{3} \times 24$ lattice at $β= 6.0$ with Wilson fermions for a range of quark masses from strange to charm. We determine the finite lattice renormalization for both the local and point-split currents of heavy quarks. Results extrapolated to the chiral limit show that the $q^2$ dependence of the axial form factor agrees reasonably well with experiment. The axial coupling constant $g_A$ calculated for the local and the point-split currents is about 6\% and 12\% smaller than the experimental value respectively.

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K. F. Liu, S. J. Dong, T. Draper, J. M. Wu, W. Wilcox. 1993-05-27. Nucleon Axial Form Factor from Lattice QCD. https://doi.org/10.1103/physrevd.49.4755

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