Electron-capture decays of 100Tc and 116In and nuclear structure relevant for 2β decays

Abstract

Both l00Mo and 116Cd are double-β-decay candidates, whose intermediate (virtual) state is a nucleus with Jπ = 1+ in the ground state. Consequently, in these cases one can measure the ‘single-β-decay’ matrix elements in addition to the 2ν-decay rate and test models in a more stringent way. We have measured the electron-capture decays of 100Tc and 116In which show that: a) the ‘ground state dominance hypothesis’ works very well; b) deformation plays a role which cannot be neglected in QRPA calculations. QRPA predictions work better in the spherical A = 116 system than in the ‘transition’ A = 100 system.