An important aspect for understanding the structure of nuclei far from stability relies on our ability to be able to explain the evolution of collectivity with proton and neutron number. The region that lies just above the Z=50 closed shell in the vicinity of N=Z exhibits interesting collective properties of quadrupole and octupole character.
The strongest octupole collectivity has been predicted for the very light Xe and Ba isotopes with N ≈ Z ≈ 56. Octupole transition probabilities have been determined for the nucleus 114Xe, being the deduced B(E3) transition matrix elements for the 3− --> 0+ and 5− --> 2+ transitions, 77(27) and 68(17) W.u. respectively, i.e., about the largest measured transition moments hitherto.
With the present experiment, we aimed to address specific aspects of the collectivity development when approaching the N=Z line in even lighter Xe isotopes by performing a precise lifetime measurement of the 5- state in 112Xe, which theoretically is expected to present a larger octupole collectivity than 114Xe. In addition, we investigate the quadrupole degree of freedom through the lifetime of the 2+ and 4+ measured for the first time.