Identification of 180Pb

The α decay of the new isotope 180Pb was observed in 40Ca bombardments of 144Sm: E α = 7.23(4) MeV, and, \({T_{1/2}} = \left( {4_{ - 2}^{ + 4}} \right){\text{ ms}}\). With this decay energy and the known mass of 176Hg, the mass excess of 180Pb was calculated to be −1.98(5) MeV.