Band structures of 131Ce

• Main Author: Alwaleedi, Mohammed
• Other Authors: Nolan, Paul
• Published: University of Liverpool 2013
• Subjects: 530; QC Physics
• Online Access: http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.617418

High-spin states have been studied in the neutron-deficent odd-N 131Ce nucleus. The experiment was performed at Argonne Laboratory, USA, using the fusion evaporation reaction 100Mo(36S,5n ). The beam of 36S was produced by the Argonne Tandem Linac Accelerator System (ATLAS) to an energy of 165 MeV with a beam current of 5 pnA. The gamma ray coincidence data were recorded with GAMMASPHERE. A detailed spectroscopic study of the 131Ce nucleus has established two new band structures and extended some of the known bands to higher spin. Cranked Woods- Saxon calculations have been used to assign possible configurations for the newly found structures. Angular intensity-ratio measurements have been performed to gain information on the multipolarities of transitions in this nucleus. In order to strengthen the suggested configuration for the 131Ce bands a comparison was carried out between the experimental and theoretical B(M1)/B(E2) ratios of reduced transition probabilities. A large signature splitting in the negative-parity bands is discussed as evidence for non-axial nuclear shape which is induced by the core-polarisation effects of neutrons from the upper h11/2 midshell.