High-spin structures in Xe132 and Xe133 and evidence for isomers along the N=79 isotones

Abstract

The transitional nuclei Xe132 and Xe133 are investigated after multinucleon-transfer (MNT) and fusion-evaporation reactions. Both nuclei are populated (i) in Xe136+Pb208 MNT reactions employing the high-resolution Advanced GAmma Tracking Array (AGATA) coupled to the magnetic spectrometer PRISMA, (ii) in the Xe136+Pt198 MNT reaction employing the GAMMASPHERE spectrometer in combination with the gas-detector array CHICO, and (iii) as an evaporation residue after a Te130(α,xn)Xe134−xn fusion-evaporation reaction employing the HORUS γ-ray array at the University of Cologne. The high-spin level schemes are considerably extended above the Jπ=(7−) and (10+) isomers in Xe132 and above the 11/2− isomer in Xe133. The results are compared to the high-spin systematics of the Z=54 as well as the N=78 and N=79 chains. Furthermore, evidence is found for a long-lived (T1/2≫1μs) isomer in Xe133 which closes a gap along the N=79 isotones. Shell-model calculations employing the SN100PN and PQM130 effective interactions reproduce the experimental findings and provide guidance to the interpretation of the observed high-spin features.3 MoreReceived 9 June 2017DOI:https://doi.org/10.1103/PhysRevC.96.024321©2017 American Physical SocietyPhysics Subject Headings (PhySH)Research AreasElectromagnetic transitionsIsomer decaysLifetimes & widthsNuclear spin & parityNuclear structure & decaysShell modelProperties90 ≤ A ≤ 149Nuclear Physics