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Nucleon Structure from Lattice QCD

Keh-Fei Liu
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Abstract

We report results on the nucleon structure obtained from the lattice quantum chromodynamics calculation. These include the axial, electromagnetic, $πNN$, and scalar form factors. The calculation is carried out at $β= 6$ on a $16^3 \times 24$ lattice with 24 quenched gauge configurations. The chiral limit results are extrapolated from several light quark cases. For the disconnected insertion (sea-quark contribution), we used the stochastic estimation with the $Z_2$ noise to calculate the diagonal and off-diagonal traces of the inverse matrices with a size of $10^6 \times 10^6$. It is found that the $Z_2$ noise is the optimal choice and its comparison with the Gaussian noise for our quark matrix is given. For the sea-quark contribution, we report results on the strange condensate in the nucleon and the $πN σ$ term.

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Keh-Fei Liu. 1994-09-22. Nucleon Structure from Lattice QCD. https://arxiv.org/abs/hep-lat/9408007

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