With the use of an on-line mass separator, electron capture (EC) and β+ decay of the direct proton emitter Tm147 was identified in a series of Ni58+92Mo irradiations. Characteristic Er Kα x rays and an 80.9-keV γ ray were observed to decay with the half-life of Tm147. The 80.9-keV γ ray is proposed to be the transition connecting the first-excited (d3/2) and ground (s1/2) neutron-hole states in Er147. The Tm147 (EC+β+)-decay strength was deduced from K x-ray and annihilation radiation intensities. A comparison of this strength with the intensity of the 1.045-MeV proton peak leads to a Tm147 direct-proton-decay branch of 15(5)%.
ASJC Scopus subject areas
- Nuclear and High Energy Physics