A rotational band in82Zr

Abstract

The neutron deficient nucleus S2Zr has been studied through the reaction SSNi(2*Si, 2 p 2 n)82Zr with a calculated cross section of 0.3% of the total fusion cross section at E(2ssi)= 128 MeV. Gamma rays from excited states of S2Zr were measured and identified using the NORDBALL escape-suppression array at the Niels Bohr Institute. Reaction channel selection was performed by use of neutron and charged particle detector arrays in conjunction with the germanium detectors. A rotational band in 82Zr has been identified with spins up to 20 h by analysis of reaction channel selected 7-7 coincidence matrices. Band crossings were identified at frequencies 0.57 and 0.69 MeV.

Collectivity in light zirconium isotopes: Evolution with neutron number and angular momentum

“…greatly extended[23]. Here, the deformation of the ground state has been established and the lifetimes ofthe first and second excited states refIect the fact, B (E2:2~0 + ) = 1840+185 e fm, 8 (E2:4~2 + ) =993+253 e fm .…”

“…The lifetime of the first excited state was measured as~=40+4 ps and the second as~=8+2 ps. These measurements have become relevant in the context of this work and with the publication of a more detailed investigation of the decay scheme by Mitarai et al [23]. Using the same reaction, but a much more eKcient spectrometer, they were able to trace the evolution of the ground-state band to spin J=20A.…”