Search for β-delayed fission of the heavy neutron-rich isotope 230Ac

The 230Ra has been produced via multinucleon transfer reaction and dissipative fragmentation by 60 MeV/u 18O ion irradiation of 232Th targets. The radium was radiochemically separated from the mixture of thorium and reaction products. Thin Ra sources were prepared and exposed to the mica fission track detectors, and measured by a HPGe gamma detector. It is likely that the β-delayed fission of 230Ac was observed for the first time and the β-delayed fission probability of 230Ac was tentatively found to be (1.19±0.40)×10-8.