Nuclear Charge Distributions of Isotone Pairs. I.P31andS32

Elastic cross sections for electron scattering from ${}_{}{}^{31}{}_{}{}^{}\mathrm{P}$ and ${}_{}{}^{32}{}_{}{}^{}\mathrm{S}$ are given for the momentum-transfer range from 0.7 to 2.9 ${\mathrm{fm}}^{-1\mathrm{}}$. The data were analyzed by means of a phase-shift code using phenomenological Fermi charge distributions modified with small undulations. The difference of the ${}_{}{}^{31}{}_{}{}^{}\mathrm{P}$ and ${}_{}{}^{32}{}_{}{}^{}\mathrm{S}$ charge distributions has been compared with a $2s_{\frac{1}{2}}$ proton distribution and with other nuclear models.