Development of wide view gamma-ray Imaging Detector

宽视场伽马射线成像探测器的研制

• 批准号: 12354002
• 负责人: TANIMORI Toru
• 金额: $ 23.96万
• 依托单位: KYOTO UNIVERSITY
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (A)
• 财政年份: 2000
• 资助国家: 日本
• 起止时间: 2000 至 2002
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-12354002/
• 关键词: MeV gamma-rays; gamma-rays Imaging; Compton Scattering; MSGC; Gas Detector; Anguar Camera; TPC; γ線イメージング; コンブトン散乱; アンガーガメラ; γ線イナージング

We have proposed the new imaging method of MeV gamma rays. By measuring the direction and energy of not only a scattered gamma ray but also a scattered electron, the direction of an incident gamma ray would be principally reconstructed event by event, and a full imaging would be realized. Furthermore, one of two measured (zenith and azimuthal) angles of a scattered electron gives co an additional redundancy which enable us to reject almost all the background events by kinematic fitting. In order to detect such a fine track of the recoil electron, a fine imaging gas detector made by the micro printed board technology was proposed here.In order to obtain 3-D track of a scattered electron, the micro Time Projection Chamber(TPC) has been developed, which measures the position of the track in a few hundred micron meter pitch successively. This TPC consists of the new type of a gas proportional chamber : Micro Pixel Gas Chamber (MPGC) which is a one of wireless gas chamber and expected to be more robust and reliable than Micro Strip Gas Chamber. Here 10cm×10cm 2D-MPGC with a 400 μm pitch pixel was developed, and the high gain of 〜 15000 and the stable operation as a micro TPC with a moderated gain of 〜 5000 during one month have been achieved. Also a compact Anguar camera consisting of a 10cm×10cm×2.5cm NaI scintillator and a 5×5 one-inch phototube array was constructed to detect a recoil gamma ray. Using the micro TPC and the Anguar camera, we successfully obtained the first gamma-ray image by the full reconstruction of the direction of gamma rays event by event. Although obtained angular resolution of 〜 30°is not so good due to the inefficiency of the MPGC, it is the first time in the world to demonstrate the possibility of full gamma ray imaging.

提出了MeV γ射线成像的新方法。通过不仅测量散射伽马射线的方向和能量，而且测量散射电子的方向和能量，入射伽马射线的方向将被逐事件地基本重建，并且将实现全成像。此外，散射电子的两个测量（天顶角和方位角）角之一给co一个额外的冗余，使我们能够拒绝几乎所有的背景事件的运动学拟合。为了探测这种精细的反冲电子径迹，本文提出了一种利用微印制板技术制作的精细成像气体探测器，并研制了微型时间投影室（TPC），它可以在几百微米的间距内连续测量电子的三维径迹位置。该TPC包括一种新型的气体比例室：微像素气室（MPGC），这是一种无线气室，预计比微带气室更坚固可靠。研制了10 cm × 10 cm、像素间距为400 μm的2D-MPGC，获得了15000的高增益，并作为微型TPC稳定工作，在一个月内增益达到15000。此外，还研制了一台由10 cm × 10 cm ×2.5cm的NaI闪烁体和5×5的1英寸光电管阵列组成的小型Anguar照相机，用于探测反冲γ射线。利用微型TPC和Anguar相机，我们成功地获得了第一幅伽马射线图像，通过逐事件的伽马射线方向的完全重建。虽然由于MPGC的效率低下，获得的角分辨率不太好，但这是世界上第一次证明全伽马射线成像的可能性。

项目成果

T.Nagayoshi, T.Tanimori et al.: "Development of Gamma-Ray Direction Detector Based on MSGC"Proceedings of the Second International Workshop on EGS. 161 (2000)

T.Nagayoshi、T.Tanimori 等人：“基于 MSGC 的伽马射线方向探测器的开发”第二届 EGS 国际研讨会论文集。

H. Toyakawa, T. Fujisama, Y. Inoko, T. Nagayoshi, Y. Nishi, Y. Nishikawa, A. Ochi, M. Suzuki and T. Tanimori: "Performance of a micro-strip gas chamber in solution X-ray scattering"Nuclear Instruments and Methods A. 467. 1144-1147 (2001)

H. Toyakawa、T. Fujisama、Y. Inoko、T. Nagayoshi、Y. Nishi、Y. Nishikawa、A. Ochi、M. Suzuki 和 T. Tanimori：“微带气室在溶液 X 射线中的性能

谷森達: "サブ秒結晶構造解析を目指して"科学技術振興事業団ニュースレター. 6. 23 (2002)

Tatsu Tanimori：“以亚秒级晶体结构分析为目标”日本科学技术振兴机构通讯。6. 23 (2002)。

T. Nagayoshi, H. Kubo, A. Ochi, S. Koishi T. Tanimori and Y. Nishi: "Development of Gamma-Ray Direction Detector based on MSGC"Proceedings of the Second International Workshop on EGS. 161-167 (2000)

T. Nagayoshi、H. Kubo、A. Ochi、S. Koishi T. Tanimori 和 Y. Nishi：“基于 MSGC 的伽马射线方向探测器的开发”第二届 EGS 国际研讨会论文集。

T.Nagayoshi et al.: "Performance of large area Micro Pixel Chamber"Nuclear Instruments and Methods in Physics Research Sect. A. (in press). (2003)

T.Nagayoshi等人：“大面积微像素室的性能”物理研究组核仪器和方法。