Validation of chemical separation method for the determination of 63Ni using TDCR technique in steel samples of APSARA reactor

Activity Standards of 63Ni was used to benchmark our triple-to-double coincidence ratio (TDCR) primary standardization instrument Hidex 300SL TDCR device under different chemical and colour quench conditions. The results were compared with a secondary standardization instrument Tricarb 2910TR that employs transformed spectral index of external standard to assess the quench level of samples. Excellent agreement was observed (within 3 %) for a wide range of standard activity and quench conditions. The method was subsequently used for validating chemical separation procedure for estimation of 63Ni in neutron activated standard nickel and steel samples. Further the method was applied for estimation of 63Ni from decommissioning waste of a research reactor, APSARA.