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Magnetization screening from gluonic currents and scaling law violation in the ratio of magnetic form factors for neutron and proton

M. M. Kaskulov·P. Grabmayr
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Abstract

The ratio ${μ_p}G_E^p/G_M^p$ exhibits a decrease for four-momentum transfer Q^2 increasing beyond 1 GeV^2 indicating different spatial distributions for charge and for magnetization inside the proton. One-gluon exchange currents can explain this behaviour. The SU(6) breaking induced by gluonic currents predicts furthermore that the ratio of neutron to proton magnetic form factors ${μ_p}G_M^n/{μ_n}G_M^p$ falls with increasing Q^2. We find that the experimental data are consistent with our expectations of an almost linear decrease of the ratio ${μ_p}G_M^n/{μ_n}G_M^p$ with increasing Q^2, supporting the statement that the spatial distributions of magnetization are different for protons and for neutrons.

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M. M. Kaskulov, P. Grabmayr. 2003-06-24. Magnetization screening from gluonic currents and scaling law violation in the ratio of magnetic form factors for neutron and proton. https://doi.org/10.1103/physrevc.69.028201

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