Decay correction of 95Nb.

The (95)Nb/(95)Zr activity ratio can be used to determine the date of a nuclear event. Several proficiency test exercises organised by the National Physical Laboratory (NPL) showed in general relatively poor results for (95)Nb, presumably caused by incorrect decay corrections. In this paper, the integrated Bateman equation taking account of the multiple branching of the parents (95)Zr and (95m)Nb, ingrowth/decay during measurement and the decay correction to a specific reference time is presented.