The level structure of the N=60 isotone ${}_{}{}^{100}{}_{}{}^{}\mathrm{Zr}$ has been studied via the decay of the low-spin isomer of ${}_{}{}^{100}{}_{}{}^{}\mathrm{Y}$. A half-life of 735±7 ms was determined from γ-ray multiscaling measurements. γ singles and γ-γ coincidence measurements have resulted in the placement of 64 γ transitions in a decay scheme with 20 levels up to 4288 keV. Angular correlation measurements were used to deduce a $J^{\pi }$ of $0^{+}$ for the 829-keV level. A simple band-mixing calculation is presented which supports a picture of the structure of the low-lying levels in ${}_{}{}^{100}{}_{}{}^{}\mathrm{Zr}$ as that of coexistence between an axially symmetric deformed yrast band and a nearly spherical excited band.

• Received 3 September 1985

DOI:https://doi.org/10.1103/PhysRevC.33.677