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arXiv · 1403.6537

Determination of the strange nucleon form factors

P. E. Shanahan·R. Horsley·Y. Nakamura·D. Pleiter·P. E. L. Rakow·G. Schierholz·H. Stüben·A. W. Thomas·R. D. Young·J. M. Zanotti
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Abstract

The strange contribution to the electric and magnetic form factors of the nucleon is determined at a range of discrete values of $Q^2$ up to $1.4$ GeV$^2$. This is done by combining recent lattice QCD results for the electromagnetic form factors of the octet baryons with experimental determinations of those quantities. The most precise result is a small negative value for the strange magnetic moment: $G_M^s(Q^2=0) = -0.07\pm0.03\,μ_N$. At larger values of $Q^2$ both the electric and magnetic form factors are consistent with zero to within $2$-sigma.

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P. E. Shanahan, R. Horsley, Y. Nakamura, D. Pleiter, P. E. L. Rakow, G. Schierholz, H. Stüben, A. W. Thomas, R. D. Young, J. M. Zanotti. 2015-02-16. Determination of the strange nucleon form factors. https://doi.org/10.1103/physrevlett.114.091802

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