Many long-lived non-gamma emitting radioactive nuclei such as 129I, 14C and 93Zr are produced as wastes from nuclear fuel cycle facilities. They are called "difficult-to-measure" radio nuclei. Among them 129I is a long-lived β-emitting isotope with a half-life of 1.57 × 107 years. Iodine compounds are mobile in the vadose zone and groundwater and increase a significant long-term risk. Transmutation of 129I is a challenging issue in nuclear waste management and disposal. If 129I is transmuted into 128I (half life; 25 minutes), it can easily be measured by a Ge detector. However, the 129I(γ, n) reaction cross section has not been measured so far. In this study we have measured the inclusive 129I(γ, n)128I cross section by using bremsstrahlung photons. The bremsstrahlung photons were produced from a 30-MeV electron linac. Measured average activation cross section agrees with 12% deviation from the evaluated one in the IAEA photonuclear data library. Gamma and neutron fluxes for the (γ, n) and the (n, γ) reaction were also calculated by the EGS and the MCNP codes.
All Science Journal Classification (ASJC) codes
- Nuclear and High Energy Physics
- Nuclear Energy and Engineering