Towards new proton radioactivities with radioactive beams and digital signal processing

Particle radioactivity studies using the XIA DGF-4C digital signal processing units at the Recoil Mass Separator of Oak Ridge National Laboratory are presented. Proton emission signals were observed starting from 500 ns after recoil implantation. An energy threshold below 100 keV for particle detection was achieved. For the 145Tm and 146Tm decay, evidence for the fine structure in proton emission was obtained. An experiment to search for a new proton emitter 149Lu is described as an example where the combination of a 56Ni radioactive beam and digital signal processing is a major advantage.