Abstract
-decay half-lives of new neutron-rich isotopes and produced in the 20 MeV proton-induced fission of have been determined to be 19.4(27) s and 8.2(13) s, respectively, using a gas-jet coupled on-line isotope separator. The present half-lives and those of the recently identified nuclei were compared with theoretical predictions. The recent calculation by the gross theory with the new one-particle strength functions shows quite good agreement with the experimental half-lives. Excited states of the daughter nuclides and have been established for the first time. Level energies of the first states in even-even Dy isotopes were found to show an irregular behavior at and increasing deformation toward the neutron midshell around .
- Received 19 January 1999
DOI:https://doi.org/10.1103/PhysRevC.59.3060
©1999 American Physical Society