MCNPX Simulation of Scattered Neutron Distribution in Experimental Room for the Neutron Reference Field of Monoenergetic Neutron below 2.5 MeV

2.5 MeV 이하 단색 중성자 표준장에 대한 중성자 실험실내의 산란 중성자 분포 전산모사

  • 박중헌 (한국지질자원연구원 지질자원분석센터) ;
  • 김기동 (한국지질자원연구원 지질자원분석센터)
  • Received : 2011.02.18
  • Accepted : 2011.06.27
  • Published : 2011.06.30

Abstract

It is important to reduce indirect scattered neutron beside direct neutron of chosen energy for designing a neutron-reference-field laboratory with neutron produced from a nuclear reaction by a accelerator. Therefore MCNPX simulation was performed with various conditions for obtaining such condition. At first in the original laboratory condition we calculated the direct neutron flux which was inserted in chamber (virtual chamber composed of air) of 0 degree (proton moving direction) for neutron flux measurement and the scattered neutron flux which is inserted in the chamber after scattering wall or bottom. In the result, the scattered neutron which was inserted after scattering bottom is more than that which was inserted after scattering the others. Therefore MCNPX simulation was again performed with removing the concrete bottom and with removing the concrete bottom and digging 1 m in the ground. In the result of removing concrete bottom and digging 1 m in the ground, scattered neutron which was inserted after scattering bottom became less than that which was inserted after scattering the others.

References

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