The heaviest known examples of proton radioactivity, Re and Ta, have been discovered. Evaporation residues from fusion reactions of 300 MeV Ni ions with Cd targets have been mass separated in flight and implanted into a double-sided silicon strip detector. The measured proton energies, total half-lives, and proton branching ratios are 1261±6 keV, 790±160 μs, (91±10)%, and 1022±13 keV, 165 ms, ≈100% for Re and Ta, respectively, indicating that the protons are emitted from a d orbital in each case. An energy of 6537±16 keV has been measured for the Re alpha decay branch.
|Number of pages||4|
|Journal||Physical Review Letters|
|Publication status||Published - 2 Mar 1992|