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Separation of Uranium and Thorium for 230Th-U Dating of Submarine Hydrothermal Sulfides
Published on: May 20, 2019
Half-life determination and comparison of activity standards of 231Pa
Simon Jerome1, Christophe Bobin2, Philippe Cassette2
1National Physical Laboratory (NPL), Teddington, UK; Bureau International des Poids et Mesures (BIPM), Sèvres, France.
Abstract:
The results of an international comparison of activity measurements of a solution of 231Pa are reported and analysed. Prior to this, no known standardisation of 231Pa by activity measurement had been carried out. The comparison was run in 2017-2018 involving eight laboratories, and returned results with no identifiable inconsistencies between methods or laboratories. The results, including one mass determination, gave a231Pa activity concentration of 41.461(48) kBq g-1 and a231Pa atom concentration of 61.48(23) × 1015 atoms g-1, from which a half-life value of 32 570(130) years was derived.
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