Alpha-decay half-life of 151Tb

Abstract

The decay of 151Tb was studied to resolve between conflicting values that have been measured for the alpha-decay half-life of 151Tb. By determining the alpha-decay and total decay rates of a chemically purified sample that contained mainly 151Tb activity, an α/total branching ratio of (8.3±2.5) × 10 −5 was calculated. This ratio corresponds to an alpha half-life of 25±7 y. The indication then is that the alpha decay rate of 151Tb, in comparison to the decay rates of neighboring doubly even alpha emitters, is hindered by a factor of about 4.5 and not≳ 100 as has been reported by some investigators.