A calculation method for parameters of secondary neutron source in nuclear reactor

[Background] In the design of nuclear reactor, it is significant to determine the parameters of secondary neutron source. [Purpose] The aim of this paper is to elaborate a calculation method for parameters of secondary neutron source systematically. [Methods] Firstly, compositions of the fuel and secondary neutron source were generated by depletion calculation. Then, gamma production and photonuclear reaction in secondary neutron source were simulated. Specific parameters of secondary neutron source, such as source strength, energy spectrum and space distribution, have been obtained. [Results] The parameters of secondary neutron source have been used to calculate the response of detectors outside the core. The results are in agreement with the measurements. [Conclusion] The calculation method suggested in this paper is available. (authors)