The levels of ${}_{}{}^{88}{}_{}{}^{}\mathrm{Sr}$ up to an excitation energy of 7 MeV have been investigated by the ${}_{}{}^{86}{}_{}{}^{}\mathrm{Sr}\mathrm{}(t,p)\mathrm{}$ reaction with 15-MeV tritons. Proton spectra were measured by a $\Delta E-E$ counter telescope system with an over-all resolution of 35 keV, and close-lying peaks were resolved by additional measurements with a magnetic spectrograph. Angular distributions were measured from 12.5 to 90°, and comparisons with zero-range distorted-wave Born-approximation calculations permitted spin assignments of 32 of the 45 levels observed. Four excited $0^{+}$ states were observed. From a comparison of their cross sections with the ${}_{}{}^{88}{}_{}{}^{}\mathrm{Sr}\mathrm{}(t,p)\mathrm{}{}_{}{}^{90}{}_{}{}^{}\mathrm{Sr}$ groundstate cross section, no one of them could be identified as the pairing vibration state; the strength of the latter appears to be fragmented. The data are compared with previous information on the ${}_{}{}^{88}{}_{}{}^{}\mathrm{Sr}$ level structure.

• Received 22 April 1970

DOI:https://doi.org/10.1103/PhysRevC.2.1020