Electron scattering form factors were measured for the low-lying levels of ${}_{}{}^{19}{}_{}{}^{}\mathrm{F}$ and ${}_{}{}^{40}{}_{}{}^{}\mathrm{Ca}$ for momentum transfers between 0.55 and 1.00 ${\mathrm{fm}}^{-1\mathrm{}}$. Elastic scattering from ${}_{}{}^{19}{}_{}{}^{}\mathrm{F}$ yields an rms charge radius of 2.885±0.015 fm. Transition strengths and transition radii are obtained for the lowest ${\frac{5}{2}}^{+}$, ${\frac{5}{2}}^{-}$, and ${\frac{3}{2}}^{+}$ states in ${}_{}{}^{19}{}_{}{}^{}\mathrm{F}$. A deformed rotational model gives a very good fit to the form factors for the positive-parity levels with ground-state deformation parameters of ${\beta }_2=0.41\mathrm{}$ and ${\beta }_4=0.17\mathrm{}$. The form factors for excitation of the $3^{-}$ and $2^{+}$ states in ${}_{}{}^{40}{}_{}{}^{}\mathrm{Ca}$ are analyzed by phase-shift analysis, and transition strengths and transition radii are also obtained for these levels.

• Received 25 October 1972

DOI:https://doi.org/10.1103/PhysRevC.7.1396