Half-life of 92Nb

The long-lived nuclide 92Nb together with 91Nb and 94Nb were produced from Mo by neutron irradiation. The activities of the nuclides were determined by γ spectroscopy and the atomic abundances were determined by mass spectrometry. Intercomparison of 92Nb and 94Nb activities and abundances yielded a value for half-life (92Nb) = (3.3 ± 0.5) × 107 yr based on a value for half-life (94Nb) = 2.0 × 104 yr. The same value was obtained within errors from absolute counting data and dilution analysis.