Speaker
Description
Since N=56 is one of the so-called "octupole magic numbers", $^{96}\mathrm{Zr}$ is expected to show a strong octupole collectivity. According to several experiments carried out about 30 years ago to determine the $B(E3; 0^{+}_1 \rightarrow 3^{-}_1 )$ value, it is one of the largest in the entire nuclear chart. However, the results differ by $30\%$. We therefore carried out an experiment at ILL in April 2024 to determine the observables required to conclude on the octupole collectivity: the lifetime of the first $3^-$ state and the branching ratio in its decay. For this purpose, $^{96}\mathrm{Y}$ was produced in a $^{235}\mathrm{U}(\mathrm{n}_{th},\mathrm{f})$ fission reaction and subsequently selected by LOHENGRIN. The decay product $^{96}\mathrm{Zr}$ was analysed with a HPGe CLOVER detector, four LaBr$_3$(Ce) scintillation detectors and a plastic $\beta$-detector in close geometry. The status of the analysis will be presented.
This work was supported by EURO-LABS.
