Development of low energy neutron spectrometer for accelerator based neutron source for BNCT

研制了一台用于北京正负电子对撞机加速器中子源的新型低能中子谱仪。对于BNCT来说，中子场的特性是一个至关重要的问题，特别是对于ABN。然而，对表热中子的测量并不简单。在这项研究中，使用位置灵敏正比计数器作为其两边是中子的入射窗口，测量探测深度分布。将测得的探测深度分布转换为中子能谱。为了证实测量从热区到表热区能量范围内的中子谱的可行性，研制了原型探测器。

A new low-energy neutron spectrometer for accelerator based neutron source (ABNS) for BNCT has been developed. For BNCT, it is a crucial issue to characterize the neutron field especially for ABNS. However, measurement of epi-thermal neutrons is not straightforward. In this study, using a position sensitive proportional counter as its one edge of the two is an entrance window of neutrons, detection depth distribution is measured. The measured detection depth distribution is converted to the neutron energy spectrum. Prototype detectors were produced to confirm the feasibility to measure the neutron spectrum in energies from thermal to epi-thermal region.