Optimization of water-pumping-injection multi-homocentric sphere neutron spectrometer

Abstract

The self-developed pumping water multi-layer concentric neutron spectrometer response function exists a ladder shape, which is not conducive to the subsequent neutron spectrum. The FLUKA program is used to optimize the structure of the multi-layer concentric sphere neutron spectrometer. The response functions of stainless steel, aluminum, lead and leaded glass (divided into sandwich and double-layer combination) to the 3He detector were obtained by simulating the inner shell materials with energy in the interval of 0.01 eV–1 GeV. The results show that when the shell material is aluminum and lead glass, the response function does not appear stepped, and the response functions of the other materials appear stepped. Therefore, the use of aluminum and lead glass instead of stainless steel as the casing of the pumped water multi-layer concentric neutron spectrometer can make its energy spectrum measurement more accurate.