Elastic magnetic electron scattering from 41Ca.

Abstract

The elastic magnetic form factor of $^{41}\mathrm{Ca}$ has been determined by 180\ifmmode^\circ\else\textdegree\fi{} electron scattering in the momentum-transfer range 0.9--2.0 ${\mathrm{fm}}^{\mathrm{\ensuremath{-}}1}$. An analysis of the data indicates that the amplitudes of the M3 and M5 multipoles are quenched by factors of 0.57\ifmmode\pm\else\textpm\fi{}0.16 and 0.68\ifmmode\pm\else\textpm\fi{}0.07 relative to the simple shell model. In contrast, the magnitude of the M7 form factor is in good accord with this model. Calculations that include multiparticle-multihole configurations in the 1${\mathit{f}}_{7/2}$ and 1${\mathit{d}}_{3/2}$ subshells, first-order core polarization to higher excited orbitals, and meson exchange currents give reasonable agreement with the data for all multipoles. The rms radius of the 1${\mathit{f}}_{7/2}$ neutron orbit was determined by means of a combined analysis of our results and previous data obtained at higher momentum transfers. After correcting for core polarization and meson exchange currents, the radius was found to be 3.96\ifmmode\pm\else\textpm\fi{}0.05 fm, in agreement with the predictions of mean-field calculations.