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arXiv · hep-lat/9901009

Flavor Singlet Axial Vector Coupling of the Proton with Dynamical Wilson Fermions

S. Güsken·P. Ueberholz·J. Viehoff·N. Eicker·T. Lippert·K. Schilling·A. Spitz·T. Struckmann
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Abstract

We present the results of a full QCD lattice calculation of the flavor singlet axial vector coupling $G_A^1$ of the proton. The simulation has been carried out on a $16^3\times 32$ lattice at $β=5.6$ with $n_f=2$ dynamical Wilson fermions. It turns out that the statistical quality of the connected contribution to $G_A^1$ is excellent, whereas the disconnected part is accessible but suffers from large statistical fluctuations. Using a 1st order tadpole improved renormalization constant $Z_A$, we estimate $G_A^1 = 0.20(12)$.

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S. Güsken, P. Ueberholz, J. Viehoff, N. Eicker, T. Lippert, K. Schilling, A. Spitz, T. Struckmann. 1999-04-14. Flavor Singlet Axial Vector Coupling of the Proton with Dynamical Wilson Fermions. https://doi.org/10.1103/physrevd.59.114502

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