First observation of the beta decay of neutron-rich Bi-218 by the pulsed-release technique and resonant laser ionization
De Witte, H × Andreyev, Andrei Borzov, IN Caurier, E Cederkall, J De Smet, H Eeckhaudt, S Fedorov, DV Fedosseev, VN Franchoo, S Górska, M Grawe, H Huber, G Huyse, Marc Janas, Z Köster, U Kurcewicz, W Kurpeta, J Plochocki, A Van de Vel, K Van Duppen, Piet Weissman, L #
American physical soc
Physical Review C vol:69 pages:1-6
The neutron-rich isotope Bi-218 has been produced in proton-induced spallation of a uranium carbide target at the ISOLDE facility at CERN, extracted from the ion source by the pulsed-release technique and resonant laser ionization, and its beta decay is studied for the first time. A half-life of 33(1)s was measured and is discussed in the self-consistent continuum-quasi particle-random-phase approximation framework that includes Gamow-Teller and first-forbidden transitions. A level scheme was constructed for Po-218, and a deexcitation pattern of stretched E2 transitions 8(+)-->6(+)-->4(+)-->2(+)-->0(+) to the ground state is suggested. Shell-model calculations based on the Kuo-Herling interaction reproduce the experimental results satisfactorily.