Study on electro-magnetic calorimeter with lead fluorite crystal

萤石铅晶体电磁热量计的研究

• 批准号: 12640300
• 负责人: INAGAKI Taroo
• 金额: $ 1.98万
• 依托单位: High Energy Accelerator Research Organization
• 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-12640300/
• 关键词: optical crystal; radiation detector; calorimetry; チェレンコフ発光体

The purpose of the present study is to establish the method to make lead fluoride crystal and to find application to calorimetric detector of the high energy particle. Since lead-fluoride crystal has no scintillation, it will be used as a Cherenkov radiator. The properties of lead fluoride are quite different from those of lead-glass which is widely used. It has heavier density, larger refractive index and better transparency in short wave length of light and has been expected to improve high-energy calorimetric detection using Cherenkov light. Ai first we studied the fabrication method of lead fluoride crystal and finally obtained nine samples of 2 X 2 X 10 cm^3. They are very transparent and show a good property comparable to the world best crystals. We found also non-easiness for fabrication of large crystal. Most of samples are broken during polish. This is due to the fact that an internal stress remains after the process of cool-down from high temperature to grow crystal. Since lead fluoride has two different crystal structures in high and room temperature, two structure can co-exist in one crystal for the cool-down crystals. We tried to find a method to avoid the co-existence by changing the cool-down speed, but the best way has not yet been established. For the nine samples, we performed a test using a high energy beam of electrons, pions and muons in November 2001. The data are being analyzed now. Moreover, we studied a possibility to use as a tool to separate neutron and gamma of GeV energy by stacking scintillator and cherenkov radiators. Lead fluorite is a possible candidate of the cherenkov radiator. The results of its model test was published.

本研究的目的是建立氟化铅晶体的制备方法并应用于高能粒子量热探测器。由于氟化铅晶体没有闪烁，它将被用作切伦科夫辐射器。氟化铅的性质与广泛使用的铅玻璃有很大的不同。它具有更重的密度，更大的折射率和更好的透明度，在短波长的光，并已被期望改善使用切伦科夫光的高能量热检测。我们首先研究了氟化铅晶体的制备方法，最终获得了9个2 × 2 × 10 ~（-3）cm ~ 3的样品。它们非常透明，显示出与世界上最好的晶体相媲美的良好性能。我们还发现制造大晶体的不容易性。大多数样品在抛光过程中破裂。这是由于在从高温冷却以生长晶体的过程之后仍然存在内应力的事实。由于氟化铅在高温和室温下具有两种不同的晶体结构，因此对于冷却晶体，两种结构可以共存于一种晶体中。我们试图找到一种方法来避免共存通过改变冷却速度，但最好的方法还没有建立。2001年11月，我们用高能电子束、π介子和μ介子对这9个样品进行了测试。数据正在分析中。此外，我们研究了一种可能性，作为一种工具，分离GeV能量的中子和γ的闪烁体和切伦科夫辐射体堆叠。萤石铅是一种可能的切伦科夫辐射体。其模型试验结果已公布。

项目成果

渡辺丈晃: "Scintillator-Lucite Sandwich detector for n/γ separation in the GeV energy region"Nuclear Instruments and Method プレプリント KEK Preprint 2001-51. (発行待ち).

Takeaki Watanabe：“用于 GeV 能量区域 n/γ 分离的闪烁体-有机玻璃三明治探测器”核仪器和方法预印本 KEK 预印本 2001-51（等待出版）。

H. Watanabe et al.: "Scintillator - Lucite sandwich detector for n/γ separation in the GeV energy region"Nuclear Instruments and Methods. KEK Preprint 2001-52 (to be published).

H. Watanabe 等人：“闪烁体 - 用于 GeV 能量区域中 n/γ 分离的有机玻璃夹层探测器”KEK 预印本 2001-52（待出版）。

渡辺文晃: "Scintillator-Lucite sandwich detector for n/y Separation in the Gev energy region"Nuclear Instruments and Method プレプリント KER Preprint 2001-51. (発行待ち).

Fumiaki Watanabe：“用于 Gev 能量区域 n/y 分离的闪烁体-有机玻璃夹层探测器”核仪器和方法预印本 KER 预印本 2001-51（等待出版）。