Discovery of the new proton emitter 144Tm

Evidence for the proton decay of 144Tm was found in an experiment at the Recoil Mass Spectrometer at Oak Ridge National Laboratory. The 144Tm events were found in the weak p5n channel of the fusion reaction using a 58Ni beam at 340 MeV on a 92Mo target. The observed proton decay energies are 1.70 MeV and 1.43 MeV and the half-life ∼ 1.9 µs. The decay properties suggest proton emission from the dominant πh 11/2 part of the wave function and from the small πf 7/2 admixture coupled to a quadrupole vibration.