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Contributions of strange quarks to the magnetic moment of the proton

H. -W. Hammer·D. Drechsel·T. Mart
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Abstract

Using the Gerasimov-Drell-Hearn sum rule and experimental total cross sections for photoproduction of $η$, $K$ and $ϕ$ mesons on the proton, we obtain upper bounds for the contribution of strange quarks to the anomalous magnetic moment of the proton, $|κ_{s}| \le 0.20 κ_{p}$. The proposed experiments to measure the spin-dependence of the absorption cross section are expected to lower these bounds considerably. The existing data on $η$ production and phenomenological models for $K$ production agree with a negative sign for $κ_{s}$.

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H. -W. Hammer, D. Drechsel, T. Mart. 1997-01-04. Contributions of strange quarks to the magnetic moment of the proton. https://arxiv.org/abs/nucl-th/9701008

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