High-spin collective structures in Pt-178 - art. no. 044323

Kondev, FG Carpenter, MP Janssens, RVF Wiedenhover, I Alcorta, M Brown, LT Davids, CN Khoo, TL Lauritsen, T Lister, CJ Seweryniak, D Siem, S Sonzogni, AA Uusitalo, J Bhattacharyya, P Reviol, W Riedinger, LL Nouicer, R Fischer, SM

Fg. Kondev et al., High-spin collective structures in Pt-178 - art. no. 044323, PHYS REV C, 6104(4), 2000, pp. 4323

53

INGLESE

Article

Physics

PHYSICAL REVIEW C-NUCLEAR PHYSICS

0556-2813 → ACNP

6104

4

2000

ISI

0556-2813(200004)6104:4<4323:HCSIP->2.0.ZU;2-#

Collective structures in Pt-178 have been investigated with gamma-ray spect roscopic techniques following mass selection. The present data expand consi derably the level scheme of this nucleus. A new collective structure has be en identified and the known bands have been extended to higher spins. Firm spin and parity assignments have been made to many levels. Of particular in terest are the negative parity bands which are interpreted in terms of stru ctures associated with octupole vibrations crossed at moderate spin by two- quasiparticle excitations. The systematics of the alpha-decay reduced width s in Pt nuclei has also been investigated. The differences of a factor of a bout 2 between the widths for the odd- and the even-A isotopes is attribute d to changes in neutron pairing associated with the blocking effect. The tr end is reproduced in calculations based on the Lipkin-Nogami pairing model.