Kr88-rb88 parent-daughter isotopic activity ratio for dating a recent nuclear event

This study reports on the nuclear event timing using Rb-88/Kr-88 isotopic activity ratio. The assessment of the zero time of a radioactive release is sometime a challenge in nuclear nonproliferation study. For a non-steady nuclear fission reaction, the dating is not possible. For the hypothesis of a nuclear explosion and for a release from a steady state nuclear fission reaction the zero-times will differ. Krypton 88 and Rubidium 88 are two radionuclide with parent-daughter relationship that is usable for a very fresh radioactive release.This study proposes some constants that can be used directly for the calculation of zero time and its upper and lower age limits. The assessment is accurate because of the calculation of zero time using a mathematical method, namely the weighted least-squares method, to evaluate an average value of the age of a nuclear event. This was done using two databases that exhibit differences between the values of some nuclear parameters, JENDL 2010 and TENDL 2011.