Nuclear Science and Engineering / Volume 193 / Number 5 / May 2019 / Pages 549-553
Technical Note / dx.doi.org/10.1080/00295639.2018.1542879
This technical note discusses radioactive decay computation with multiple source terms with heterogeneous introduction dates to the system. Two methods are considered: (1) decaying in sequence from the oldest dated source, ad finitium, to the final decay date and (2) decaying each source term to the final decay date and summing the resulting nuclides. We prove that radioactive decay computation using the prescribed two methods produces the same result. The algorithmic advantage of the second method over the first one is formally argued. The radioactive decay of 90Sr with multiple initial decay dates is given as an illustrative example.