Delayed or absent pi(h(11/2))(2) alignment in Xe-111


Capponi L., Smith J. F. , Ruotsalainen P., Scholey C., Rahkila P., Bianco L., ...Daha Fazla

PHYSICAL REVIEW C, cilt.101, 2020 (SCI İndekslerine Giren Dergi) identifier identifier

Özet

Excited states have been identified in the very neutron-deficient N = Z + 3 nucleus Xe-111 for the first time, using the Ni-58(Ni-58, alpha n) heavy-ion fusion-evaporation reaction. gamma-ray transitions have been unambiguously assigned to Xe-111 by correlation with the characteristic Xe-111 -> Te-107 -> Sn-103 alpha-decay chain using the method of recoil-decay tagging. Inspection of gamma gamma-coincidence data has shown that five of the transitions form a rotational-like sequence. Excitation-energy systematics suggest that the sequence could be the favored signature partner of a band built on an h(11/2) neutron. Aligned angular momenta of states in the band have been compared to analogous bands in neighboring xenon isotopes. The aligned angular momenta for the Xe-111 band are constant over the range of observed rotational frequencies, suggesting that the first pi(h(11/2))(2) alignment is either delayed or absent. It is speculated that the alignment of h(11/2) protons in the presence of neutrons in near-identical h(11/2) orbitals may be affected by neutron-proton interactions or by the onset of octupole correlations.