Age determination of plutonium material in nuclear forensics by thermal ionisation mass spectrometry

Age is a key parameter when deducing the history of plutonium material, i.e . the plutonium produced in the nuclear reactors. This is of vital importan ce. when a smuggled plutonium sample has been seized and the origin has to be determined. A methodology is described which allows accurately to determ ine the age of plutonium material by thermal ionisation mass spectrometry u sing independent parent/daughter relations. This has been demonstrated for Reference Materials of known ages as well as for real samples. The already established method using gamma spectrometry is compared to this.