학술논문

High-spin states in 212Po above the α-decaying (18+) isomer
Document Type
article
Source
Physics Letters B, Vol 834, Iss , Pp 137457- (2022)
Subject
γ spectroscopy
Isomer spectroscopy
High-spin spectroscopy
Physics
QC1-999
Language
English
ISSN
0370-2693
Abstract
The nucleus 212Po has been produced through the fragmentation of a 238U primary beam at 1 GeV/nucleon at GSI, separated with the FRagment Separator, FRS, and studied via isomer γ-decay spectroscopy with the RISING setup. Two delayed previously unknown γ rays have been observed. One has been attributed to the E3 decay of a 21− isomeric state feeding the α-emitting 45-s (18+) high-spin isomer. The other γ-ray line has been assigned to the decay of a higher-lying 23+ metastable state. These are the first observations of high-spin states above the 212Po (18+) isomer, by virtue of the selectivity obtained via ion-by-ion identification of 238U fragmentation products. Comparison with shell-model calculations points to shortfalls in the nuclear interactions involving high-j proton and neutron orbitals, to which the region around Z∼100 is sensitive.