Building an Internal Conversion Electron Spectrometer with High Resolution for Analysis of Actinide Nuclides

构建用于分析锕系核素的高分辨率内转换电子能谱仪

基本信息

批准号：
62880022
负责人：
SUZUKI Susumu
金额：
$ 3.78万
依托单位：
TOHOKU UNIVERSITY
依托单位国家：
日本
项目类别：
Grant-in-Aid for Developmental Scientific Research
财政年份：
1987
资助国家：
日本
起止时间：
1987 至 1988
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-62880022/
关键词：
Actinide Intenal Conversion Electron Spectrometry Isotope Ratio 同位体比同位体比測定

项目摘要

Most of the actinide nuclides are alpha-emitters and furter the actinide nuclides often have extremely low photon intensities due to their high internal conversion coefficients. Therefore, alpha ray spectrometry has been widely used as a standard analytical tool for identification and assay of actinide nuclides, instead of gamma ray spectrometry. Alpha ray spectrometer, unfortunately, has no capability to separate an energy group differing by about 10 keV. Then, it is difficult to analyze the mixtures such as <@D1239@>D2Pu and <@D1240@>D1Pu. Moreover, the high energy losses in a matter invoke tailings to lower energy in the alpha ray spectrum and further a critical requirement for an infinitely thin and weightless source. An internal conversion electron spectrometer with excellent energy resolution using a windowless Si(Li) detector was developed. The energy resolution was 0.48 keV in FWHM for 42 keV electrons. From the examination of the spectrometer, the difference of energy resolution between for electrons and for gamma rays was found to be predominantly due to the energy straggling of electrons through the absorbing layer of the detector. And the relative efficiency curve for electrons were quantitatively explained in terms of electron backscattering in the detector and electron escape from the edge. The analysis of the <@D1240@>D1Pr to <@D1239@>D1 isotope ratio was made by ICE spectrometry and it was found that the isotope ratio can be determined with excellent accuracy and precision.

大多数actinide核素是α发射体，并且由于其高内部转化系数，因此acttinide核素通常具有极低的光子强度。因此，Alpha射线光谱法已被广泛用作鉴定和测定acttinide核素的标准分析工具，而不是γ射线光谱法。不幸的是，Alpha射线光谱仪没有能力分离约10 keV的能量组。然后，很难分析诸如<@d1239@> d2pu和<@d1240@> d1pu之类的混合物。此外，物质中的高能量损失调用尾矿，以降低α射线频谱中的能量，并进一步是无限薄且不轻度源的关键要求。开发了具有出色能量分辨率的内部转换电子光谱仪，使用了无窗Si（LI）检测器。对于42 KEV电子的FWHM，能量分辨率为0.48 keV。从光谱仪的检查中，发现电子和伽马射线之间的能量分辨率差异主要是由于电子通过检测器的吸收层的能量散落。并用电子反向散射在检测器和电子逃脱边缘的电子后散射方面进行了定量解释。 <@d1240@> d1pr至<@d1239@> d1同位素比的分析是通过冰光谱进行的，发现同位素比可以以极好的精度和精度确定。