Inelastic proton scattering on the radioactive nuclei 18Ne and 20O in inverse kinematics

Elastic and inelastic scattering to the 21+ state of the single closed shell radioactive nuclei 18Ne and 20O have been measured in inverse kinematics with a beam energies of 30 MeV/u. The matrix element determined for the 0gs+→21+ transitions in these reactions are compared with the corresponding electromagnetic matrix elements to determine Mn/Mp, the ratio of the neutron and proton multipole matrix elements. A comparison between the Mn/Mp values in 20O and 18O suggests that the matrix element ratio is increasing as the neutron number increases. The Mn/Mp result for 18Ne is consistent with one obtained from a comparison of electromagnetic data from the mirror nuclei 18O and 18Ne.