# Nuclear Science and Techniques

《核技术》(英文版) ISSN 1001-8042 CN 31-1559/TL     2019 Impact factor 1.556

Nuclear Science and Techniques ›› 2013, Vol. 24 ›› Issue (6): 060406

• NUCLEAR ELECTRONICS AND INSTRUMENTATION •

### Simulation and calibration of the response function of multi-sphere neutron spectrometer

JIANG Xiaofei 1,2,* CHEN Chao 1,2 CAO Jing 1,2 CAO Hongrui 1,2#br# LI Shiping 1,2 SONG Xianying 3 YIN Zejie 1,2

1. 1State Key Laboratory of Particle Detection and Electronics, University of Science and Technology of China, Hefei 230026, China
2Department of Modern Physics, University of Science and Technology of China, Hefei 230026, China
3Southwestern Institute of Physics, Chengdu 610041, China
• Contact: JIANG Xiaofei E-mail:jxfqj@mail.ustc.edu.cn
• Supported by:

Supported by ITER Plan National Major Project 2008GB109000.

JIANG Xiaofei, CHEN Chao, CAO Jing, CAO Hongrui. Simulation and calibration of the response function of multi-sphere neutron spectrometer.Nuclear Science and Techniques, 2013, 24(6): 060406

Abstract:

In order to realize the on-line real-time measurement of neutron spectrum of ITER fusion, this paper presents a multi-sphere spectrometer system which consists of eight thermal neutron detectors, namely SP9 3He proportional counter, embedded in eight different diameter polyethylene spheres. The response function of eight polyethylene spheres of multi-sphere neutron spectrometer was calculated after the simulation of the neutron transport processes in multi-sphere spectrometer by adopting software Geant4. The peak of the response function is in the low energy region for smaller diameter polyethylene sphere. As the polyethylene sphere diameter increased, the peak of the response function moves to the high energy region. The experimental calibration adopts 241Am-Be neutron source. The relative error between normalized data of experiment 4π solid angle counts and normalized data of simulated detection efficiency of 4in to 8in polyethylene sphere is from 1.152% to 12.222%.The experimental results verify the response function of the simulation. All these results provide a theoretical and experimental basis for solving the on-line real-time neutron spectrum of ITER fusion.