Effect of gluon-exchange pair currents on the ratioμpGEp/GMp

The effect of one-gluon-exchange (OGE) pair currents on the ratio ${\mu }_p{G}_E^p{/G}_M^p$ for the proton is investigated within a nonrelativistic constituent quark model starting from $\mathrm{SU}\mathrm{}\left(6\right)\mathrm{}\times \mathrm{O}\mathrm{}\left(3\right)\mathrm{}$ nucleon wave functions, but with relativistic corrections. We found that the OGE pair currents are important to reproduce well the ratio ${\mu }_p{G}_E^p{/G}_M^p.$ With the assumption that the gluonic currents are the driving mechanism for the violation of the scaling law, we predict the neutron ratio ${\mu }_n{G}_E^n{/G}_M^n.$