ABURN: A material activation calculation code based on CRAM method

Highlights: • The Chebyshev rational approximation method (CRAM) was adopted to solve the equilibrium equations of nuclides. • Based on CRAM method and EAF-2007 nuclear database, a material activation calculation code named ABURN was developed. • In ABURN, the method of scaling and squaring was applied to make CRAM suitable for the case of long-term decay of the system with short-lived nuclides. • Three typical cases were chosen to test ABURN, and the calculation results showed high computational accuracy and efficiency of ABURN. - Abstract: Material radioactivity caused by neutron activation is one of the key issues for radiation protection in fusion reactor. In this paper, the Chebyshev rational approximation method (CRAM) was adopted to solve the equilibrium equations of nuclides, which has high computational accuracy and efficiency. Based on CRAM method and EAF-2007 nuclear database, a material activation calculation code named ABURN was developed. In ABURN, the method of scaling and squaring was applied to make CRAM suitable for the case of long-term decay of the system with short-lived nuclides. Three typical cases, including ⁵⁰Cr activation and natural Fe activation under neutron irradiation, and ^53mFe decay, were chosen to test ABURN. The calculation results of ABURN are almost the same as the analytical solutions, and the time consumption for a calculation run of ABURN is comparatively short, which means ABURN is a potential tool for material activation analysis of fusion reactor in the future.