Radiopurity assay of archaeological lead and related compounds for astroparticle physics by mass spectrometry and gamma-ray spectrometry

A novel and rapid method is introduced for determining thorium (Th) and uranium (U) concentrations in archaeological lead and related compounds to be used in astroparticle physic. This method involves chromatographic pre-concentration and inductively coupled plasma mass spectrometry (ICP-MS). Combined data from mass spectrometry and gamma-ray spectrometry measurements are presented. Excellent results were achieved in terms of reliability and sensitivity (ngˑkg -1 ), even without introducing Th and U isotopes as tracers. • Trace levels of 232 Th and 238 U in archaeological lead and tungsten-based materials • Method based on TRU resin pre-concentration with high-resolution ICP-MS • Archaeological lead, commercial WO 3 and PbWO 4 crystal samples were measured • Gamma-ray spectrometry was employed alongside ICP-MS to check secular equilibrium • The analytical protocol enabled rigorous radiopurity control for RESNOVA experiment