Using activation method to measure neutron spectrum in an irradiation chamber of a research reactor

周雪梅刘桂民李达王小鹤孟令杰

Shanghai Institute of Applied Physics,the Chinese Academy of Sciences Key Laboratory of Nuclear Radiation and Nuclear Energy Technology,Chinese Academy of Sciences University of Chinese Academy of Sciences Northwest Institute of Nuclear Technology

摘要：Neutron spectrum should be measured before test samples are irradiated.Neutron spectrum in an irradiation chamber of a research reactor was measured by using activation method when the reactor is in normal operation under 2 MW.Sixteen kinds of non-fission foils（19 reaction channels） were selected,of which 10 were sensitive to thermal and intermediate energy regions,while the others were of different threshold energy and sensitive to fast energy regions.By measuring the foil radioactivity,the neutron spectrum was unfolded with the iterative methods SAND-Ⅱ and MSIT.Finally,shielding corrections of group cross-section and main factors affecting the calculation accuracy were studied and the uncertainty of solution was analyzed using the Monte Carlo method in the process of SAND-Ⅱ.

基金资助：

Supported by"Strategic Priority Research Program"of the Chinese Academy of Science（No.XDA02001003）；