Development of Highly Sensitive Neutron Monitor with GSO Scintillators

GSO闪烁体高灵敏度中子监测仪的研制

• 批准号: 12650054
• 负责人: KOORI Norihiko
• 金额: $ 2.37万
• 依托单位: The University of Tokushima
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 2000
• 资助国家: 日本
• 起止时间: 2000 至 2001
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-12650054/
• 关键词: scintillators; low background; GSO; scintillation mechanism; environmental neutron; pulse shape analysis

In this research, highly sensitive neutron monitors are intended to be realized for measurements of environmental neutrons with GSO (Gd_2SiO_5 : Ce) scintillators. The scintillator with Gd- 157, which has a very high cross section of 254,000 b for thermal neutron capture, may be a high sensitivity neutron monitor. Followings are the results from the present research.(1) Neutron detection with a GSO scintillators : The GSO scintillator response were observed for thermal neutrons. Gamma-rays of 79.5 keV and 182 keV from Gd-158 resulted by the thermal neutron capture were confirmed with a low intensity neutron source, and then a high detection efficiency of 14 % was obtained for a 2" Φ x 2" GSO crystal. Applications will be planed to measurement of very low flux of environmental neutrons will be possible with a good shield condition of Pb, Oxigen-free Cu, and Paraffin blocks.(2) Pulse shape of scintillation from a GSO scintillators : The pulse shapes of scintillation combining with the pulse height determination were measured with a high speed digital oscilloscope. A pulse shape analyzing system were developed for this purpose, and measured the decay times of scintillation from GSO crystals of different Ce concentrations, and other LSO, BGO and BaF_2 scintillation crystals. The developed pulse shape analyzing system will be effective for discrimination of alphas from contaminants of U-series nuclei in crystals.The present research provides the knowledge about a high sensitive neutron monitor of GSO scintillators,

本研究旨在利用GSO（Gd_2SiO_5：Ce）闪烁体实现高灵敏度的中子监测器，用于环境中子的测量。具有254，000 B的热中子俘获截面的具有Gd- 157的闪烁体可以是高灵敏度中子监测器。以下是本研究的结果。(1)用GSO闪烁体进行中子探测：观测了GSO闪烁体对热中子的响应。用低强度中子源证实了热中子俘获Gd-158产生的79.5 keV和182 keV的γ射线，并在2”Φ × 2”GSO晶体上获得了14%的高探测效率。在铅、无氧铜和石蜡块的良好屏蔽条件下，将有可能应用于测量极低通量的环境中子。(2)GSO闪烁体的脉冲波形：用高速数字示波器测量了闪烁体的脉冲波形并结合脉冲高度的测定。研制了脉冲波形分析系统，测量了不同Ce浓度的GSO晶体和其它LSO、BGO和BaF_2闪烁晶体的闪烁衰减时间。脉冲波形分析系统的研制将有效地区分α粒子和晶体中U系列核的污染物，本研究提供了一种高灵敏度的GSO反应堆中子监测器的知识，

项目成果

S.Miyamoto et al.: "Radiation Measurement System by Means of Digital Oscilloscope"Proc. WS on Radiaton Detectors and Their Uses (KEK,Tsukuba). 2000-14. 201-210 (2000)

S.Miyamoto 等人：“利用数字示波器的辐射测量系统”Proc。

S. Miyamoto et al.: "Radiation Measurement System by Means of Digital Oscilloscope"Proc. WS on Radiaton Detectors and Their Uses (KEK, Tsukuba). 2000-14. 201-210 (2000)

S. Miyamoto 等人：“利用数字示波器的辐射测量系统”Proc。

S.Nakayama, N.Koori, et al.: "Dipole excitaion of α cluster in ^6Li and ^7Li"Physical Review Letters. 87(12). 122502-1-122502-4 (2001)

S.Nakayama、N.Koori 等人：“^6Li 和 ^7Li 中 α 簇的偶极激发”物理评论快报 87(12) (2001)。

S. Nakayama, N. Koori, et al.: "Dipole excitaion of α cluster in ^6Li and ^7Li"Physical Review Letters. 87 (12). 122502-[1-4] (2001)

S. Nakayama、N. Koori 等人：“^6Li 和 ^7Li 中 α 簇的偶极激发”物理评论快报 87 (12)-[1-4] (2001)。

S.Miyamoto et al.: "Radiation Measurement System by Means of Digital Oscilloscope"Proc. WS on Radiaton Detectors and Their Uses (KEK, Tsukuba). 2000-14. 201-210 (2000)

S.Miyamoto 等人：“利用数字示波器的辐射测量系统”Proc。