Half-life ofNbg92

Abstract
We have produced the long-lived ground state of Nb92 by irradiation of niobium foils with 14.8-MeV neutrons, and we have established its half-life from measurements of the disintegration rate and the neutron fluence together with the known Nb93(n,2n)Nbg92 cross section. On the basis of two separate experiments we obtain t12(Nbg92)=(3.6±0.3)×107 yr.