Determination of the long-lived ¹⁰Be in construction materials of nuclear power plants using photoactivation method

The problem of handling nuclear power plant irradiated structural materials holds one of the central places in the nuclear power industry. High toxic ¹⁰Be with a half-life of T_1/2 = 1.6 × 10⁶ years is discovered in NPP structural materials after reactor operating. ¹⁰Be decays through only electrons' emission. Pure beta emitters are extremely difficult to determine in irradiated structural materials and radioactive waste. We proposed a photoactivation approach for determining the ¹⁰Be activity in NPP samples. The proposed method involves determining ⁹Be and ¹⁰B concentrations and subsequent recalculation of ¹⁰Be activity formed in ⁹Be(n, γ)¹⁰Be and ¹⁰B(n, p)¹⁰Be reactions. The amount of ⁹Be and ¹⁰B is determined by samples' photoactivation using an electron accelerator and ⁹Be(γ, 2n)⁷Be-, ¹⁰B(γ, p2n)⁷Be-reactions. These reactions' experimental yields were measured for 20, 40, and 55 MeV boundary energies of the bremsstrahlung beam. The proposed technique was tested on samples of ChNPP 2^nd unit irradiated structural materials. The technique's calculated error is about 15-20%; the sensitivity is 1 Bq × g^-1.