Nuclear Techniques ›› 2014, Vol. 37 ›› Issue (03): 30201-030201.doi: 10.11889/j.0253-3219.2014.hjs.37.030201

• LOW ENERGY ACCELERATOR, RAY AND APPLICATIONS • Previous Articles     Next Articles

Research on the determination of 235U fission number by delayed γ-rays absorbed dose rates

SHANG Jianbo1,2 SHI Quanlin2 LIU Jie2   

  1. 1(Department of Engineering Physics, Tsinghua University, Beijing 100084, China) 2(Northwest Institute of Nuclear Technology, Xi’an 710024, China)
  • Received:2013-09-02 Revised:2013-12-17 Online:2014-03-10 Published:2014-03-14

Abstract:

Background: The determination method of 235U fission number by detecting fission products using HPGe detector has been established before. But in some special cases, we need to get the fission number in-time in high intensity radiation environment. HPGe detector has its limitation due to the complex g spectrum accompany with high flux. Purpose: To get rid of the limitation mentioned above, a new method is introduced by detecting the delayed g-rays absorbed dose rates. Methods: By using independent fission yield together with radioactive decay dates from CENDL 3.0 and ENDF BVII.1, dynamic calculation for total absorbed dose rate in air 1 meter from the source whose compositions were thermal neutron-induced fission products of 235U has been done. Results: A set of absorbed dose rate data of 235U fission products irradiated through fast rabbit irradiation system on Xi’an pulse reactor was recorded. The deviation of the fission neutron number between method by g-rays absorbed dose rates and method by HPGe detector is 7%. Conclusion: It’s feasible to determine the fission neutron number of 235U using delayed g-rays absorbed dose rates in a high intensity radiated environment.

Key words: Fission neutron number, Absorbed dose rate, Fission products