In order to examine the characteristics of lithium-ion-induced Coulomb excitation, and to extend the cross-section ratio technique for the determination of the multipolarity of transitions, a study has been made of the $\gamma$ rays emitted following electric excitation of several different target nuclei by ${\mathrm{Li}}^6$ and ${\mathrm{Li}}^7$ ions in the energy range 1.1 to 2.2 Mev. Measurements have been made of thick-target yields of the 110-kev ($E1\mathrm{}$) and 198-kev ($E2\mathrm{}$) $\gamma$ rays from ${\mathrm{F}}^{19}$, the 128-kev ($E2\mathrm{}$) $\gamma$ ray from ${\mathrm{Mn}}^{55}$, and the 160-kev ($E2\mathrm{}$) $\gamma$ ray from ${\mathrm{Ti}}^{47}$ and compared with yields calculated from the theoretical cross sections. The yields of the $\gamma$ rays studied were observed to increase with beam energy in the manner predicted by theory for electric dipole or electric quadrupole excitation. The ratios of the ${\mathrm{Li}}^6$ and ${\mathrm{Li}}^7$ induced yields at corresponding (equal $\xi$) energies for $E1\mathrm{}$ and $E2\mathrm{}$ transitions after correction for range effects were found to agree, within the estimated errors, with the theoretical predictions for cross-section ratios.

• Received 29 July 1959

DOI:https://doi.org/10.1103/PhysRev.116.1526