Trial Conversion and Applications of a Scanning Electron Microscope to Positron Microscope

扫描电子显微镜转正电子显微镜的尝试与应用

• 批准号: 09555186
• 负责人: DOYAMA Masao
• 金额: $ 5.95万
• 依托单位: Teikyo University of Science and Technology
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B)
• 财政年份: 1997
• 资助国家: 日本
• 起止时间: 1997 至 1999
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-09555186/
• 关键词: POSITRON MICROSCOPES; Scanning Positron Microscopes; Imaging Plates; 陽電子; イメジングプレート; 陽電子の減速

The final goal of the research projects is to make a positron microscope converting a used commercial electron microscope. A used scanning electron microscope JMS-25S has been moved from the Teikyo University of Science and Technology to KEK, Tsukuba and set near a liniac. A cooling system has been completed. However, the liniac reformed recently and positron beam has not been available to the microscope area. So the microscope has not been directly connected to the liniac.Positron lenses have been designed. Kinetic energies of positrons are not monovalued but continuous, either from nuclear decays or creation of positron and electron pairs. A broad beam is coming from the liniac. First, we will use a tungusten foil to reduce the kinetic energies. The work function of positrons is negative, this means thermalized positrons will be ejected from the surface with a low energy of the order of 1 eV. The ejected positrons will be focused on a nickel foil and this is repeated twice. The diameter of focused point will be of the order of one hundredth of millimeter. This is replaced with the electron gun of the scanning electron microscope.For recording positron images, we have shown for the first time in the world, that imaging plates are suitable to record positron images. We have obtained a characteristic curve of imaging plates for positrons.

本研究计画的最终目标是将商用电子显微镜转换成正电子显微镜。使用过的扫描电子显微镜JMS-25 S已从帝京科技大学搬到了筑波的KEK，并设置在Liniac附近。冷却系统已经完成。然而，由于直线加速器改造不久，正电子束还没有进入显微镜领域。所以显微镜并没有直接连接到直线加速器上，而是设计了正电子透镜。正电子的动能不是单值的，而是连续的，或者来自核衰变，或者来自正电子和电子对的产生。直线加速器发出一束宽光束。首先，我们将使用钨箔来降低动能。正电子的功函数是负的，这意味着热化的正电子将以大约1 eV的低能量从表面射出。喷射出的正电子将聚焦在镍箔上，重复两次。聚焦点的直径将是百分之一毫米的数量级。这被扫描电子显微镜的电子枪所取代。为了记录正电子图像，我们在世界上首次证明了成像板适合记录正电子图像。我们得到了正电子成象板的特性曲线。

项目成果

M Doyama: "Imaging Plates Used as Positron Microscopy-Effect of Positrons and Gamma Rays"Nuclear Instruments and Methods in Physical Research B. (2000)

M Doyama：“用作正电子显微镜的成像板-正电子和伽马射线的效应”物理研究中的核仪器和方法 B.（2000）

Masao Doyama, M.Inoue, Y.Kogure, T.kurihara, A.Yagishita, T.shidara, K.Nakahara, Y.Hayashi, T.Yoshiie, and S.Nakagawa: "Positron Microscope at KEK"Nulear Instruments and Methods in Physical Research B. in print. (2000)

Masao Doyama、M.Inoue、Y.Kogure、T.kurihara、A.Yagishita、T.shidara、K.Nakahara、Y.Hayashi、T.Yoshiie 和 S.Nakakawa：“KEK 的正电子显微镜”核仪器和方法

Masao DOYAMA: "Lattice defects in metals" Materials Chemistry AND PHYSICS. 50. 106-115 (1997)

Masao DOYAMA：“金属中的晶格缺陷”材料化学和物理学。

Masao Doyama: "Imaging Plates Used as Positron Microscopy --Effect of Positrons and Gamma Rays"Nuclear Instruments and Methods in Physical Research B. (in Print). (2000)

Masao Doyama：“用作正电子显微镜的成像板——正电子和伽马射线的效应”物理研究中的核仪器和方法 B.（印刷版）。

Masao Doyama: "Study of Positron Image Using ^<64>Cu and ^<58>Co"Kyoto University Reactor Research Institute Progress. 1997. (99)

Masao Doyama：“使用^<64>Cu和^<58>Co的正电子图像研究”京都大学反应堆研究所进展。