Fine structure in the α decay of At218

Abstract

An α-decay study of 218 At was performed at the CERN-ISOLDE facility. Laser-ionized beams of 218 At were mass separated and implanted into an α-γ detection setup. Coincidence α-γ data were collected for the first time and a more precise half-life value of T 1/2 = 1.27(6) s was measured. A new α-decay scheme was deduced based on the extracted reduced α-decay widths for fine-structure decays. The results from this work lead to a preferred spin and parity assignment of J π = (3 − ); however, J π = (2) − cannot be fully excluded.