Abstract: Based on the needs of refined analysis of activated source term at the upper and lower ends of the spent fuel assembly, through comparative analysis, different cross section libraries are applied to the calculation of activated source term at the upper and lower ends of the spent fuel assembly. The main conclusions include: The active region cross section library and thermal neutron cross section library have large calculation errors when applied to the calculation of the activated source term. The combined cross section library is conservative in the processing of the resonance group and the fast group cross-section, which leads to the conservative analysis results. The problem related cross section library is closer to the real situation.

Key words: spent fuel assembly, upper and lower ends, activated source term, problem related cross section