Coulomb excitation of cadmium isotopes with protons

Abstract

Low-lying positive parity levels of the isotopes in natural cadmium were Coulomb excited with 2.7--4.2 MeV protons. Eight levels of $^{111}\mathrm{Cd}$ up to 1130.4 keV and four levels of $^{113}\mathrm{Cd}$ up to 680.5 keV excitation energy, and the first ${2}^{+}$ states in even-even isotopes ${(}^{110}$,112,114,116Cd) were excited. A 50 ${\mathrm{cm}}^{3}$ Ge(Li) detector was used to measure the deexcitation gamma-ray yields. The 1130.4 keV level in $^{111}\mathrm{Cd}$ had not been investigated earlier through Coulomb excitation. Also the 245.4, 700, 754.9, 855.6, and 1020.7 keV levels in $^{111}\mathrm{Cd}$, and the 316.1 keV level in $^{113}\mathrm{Cd}$ were Coulomb excited with protons for the first time. The reduced E2 transition probabilities B(E2), and partial half-lives ${T}_{1/2}$ (E2), for various levels were determined. The gamma-ray angular distributions were analyzed to deduce the E2/M1 mixing ratios (\ensuremath{\delta}) for various transitions from the levels in $^{111}$,113Cd. The 700, 754.9, 855.6, and 1020.7 keV levels in $^{111}\mathrm{Cd}$, and the 680.5 keV level in $^{113}\mathrm{Cd}$ have been assigned a spin value of ${(3/2)}^{+}$, while the 1130.4 keV level in $^{111}\mathrm{Cd}$ has been assigned a spin of ${(5/2)}^{+}$. The results have been compared with existing theoretical and experimental data in the literature.