A study of beryllium moderator thickness for a fission chamber with fast neutron measurements

摘要

The detection efficiency of the fission chamber (FC) is very important for studying the neutron flux measurement (NFM) system in ITER.In this article,we mainly focus our attention on the influence of the moderator.With the Monte Carlo particle transport simulation tool named Geant4,we make a simulation of FC detection efficiency with different levels of thickness of a beryllium moderator.Two manufactured FCs for ITER-NFM systems are then used to test the parameters and performance.The test results agree well with our simulation.