The Non-Vacuum PIXE Analysis of Relics Excavated from Remains and Presumption of Their Original Places.

遗址出土文物的非真空PIXE分析及原位推定。

• 批准号: 07454096
• 负责人: SHIOMI-TSUDA Naoko
• 金额: $ 5.06万
• 依托单位: Nara Women's University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B)
• 财政年份: 1995
• 资助国家: 日本
• 起止时间: 1995 至 1997
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-07454096/
• 关键词: Elemental Analysis; Non-vacuum PIXE method; Stone implement; Presumption of production place; Soil analysis

In order to realize non-vacuum PIXE analysis we constructed a new apparatus which could lead a ion beam into the atmosphere. The appratus was installed at down-stream of a existing chamber which was used for usual vacuum PIXE analysis. A special consideration was taken for the protection of the whole accelerator system against vacuum-breaking accidents. A Kapton foil was used for the end window of the apparatus so that the window foil did not produce much background X ray. A high resolution pure germanium detector, the energy resolution of which was 135 eV for Mn K^<alpha> X ray, was used in the present measurement.Elemental analysis was performed for samples such as obsidian, sanukite, earthenware and soil. Samples of obsidian and sanukite were collected from well-known 7 places and 2 places, respectively. Earthenware were obtained from ancient tombs. Soil samples were collected from the ruins of "Heijokyo" which was a capital city of Japan at Nara era.From the PIXE analysis of obsidian and sanukite samples, the ratios of X ray yield for certain pairs of elements were found to have characteristic values and to be useful for classification of production places. The fluctuation of X ray yields was often observed when PIXE analysis was performed at different sampling positions. The present analysis shows that ratios of X ray yields for any two elements except Ca are almost constant and safely used for the classification.As for elemental analysis of soil samples obtained at Heijokyo ruins we were interested in looking for the evidence that ancient people really led their lives there. The trace elements were considered to be phosphorus and sulfur which were contained in protein and lipid. We found PK_<alpha> and S K_<alpha> X ray peaks in several samples and concluded that the presence of these elements implied the existence of human lives.

为了实现非真空PIXE分析，我们研制了一种新的能将离子束导入大气的装置。该装置安装在用于常规真空PIXE分析的现有室的下游。对整个加速器系统的真空破坏事故的保护进行了特别考虑。Kapton箔用于装置的端部窗口，使得窗口箔不产生太多的背景X射线。采用高分辨纯锗探测器，能量分辨率为135 eV<alpha>，对黑曜石、赞岐石、陶器和土壤等样品进行了元素分析。黑曜石和赞岐石样品分别采自7处和2处知名地点。陶器是从古墓中获得的。从奈良时代日本都城“平条京”遗址采集土壤样品，对黑曜石和赞岐石样品进行PIXE分析，发现某些元素对的X射线产额比值具有特征值，可用于产地分类。在不同取样位置进行PIXE分析时，经常观察到X射线产额的波动。目前的分析表明，除Ca外，任何两种元素的X射线产额比几乎是恒定的，可以安全地用于分类。至于在平城桥遗址获得的土壤样品的元素分析，我们感兴趣的是寻找古代人确实在那里生活过的证据。微量元素主要为磷和硫，主要存在于蛋白质和脂肪中。我们在几个样品中发现了PK_x<alpha>和S_K_<alpha>X射线峰，从而得出结论，这些元素的存在暗示着人类生命的存在。