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Chiral Symmetry and the Nucleon's Vector Strangeness Form Factors

M. J. Musolf·Hiroshi Ito
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Abstract

The nucleon's strange-quark vector current form factors are studied from the perspective of chiral symmetry. It is argued that chiral perturbation theory cannot yield a prediction for the strangeness radius and magnetic moment. Arrival at definite predictions requires the introduction of additional, model-dependent assumptions which go beyond the framework of chiral perturbation theory. A variety of such model predictions is surveyed, and the credibility of each is evaluated. The most plausible prediction appears in a model where the unknown chiral counterterms are identified with $t$-channel vector meson exchange amplitudes. The corresponding prediction for the mean square Dirac strangeness radius is $\langle r_s^2\rangle = 0.24$ fm$^2$, which would be observable in up-coming semileptonic determinations of the nucleon's strangeness form factors.

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M. J. Musolf, Hiroshi Ito. 1996-07-12. Chiral Symmetry and the Nucleon's Vector Strangeness Form Factors. https://doi.org/10.1103/physrevc.55.3066

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