单向聚束质子激发X射线研究超导材料合成中的重力效应

Study of Gravitation Effect in the Synthesis of Superconducting Material by Using Line focused PIXE Technique

采用质子激发Ｘ射线（ＰＩＸＥ）分析技术，以能量为２．０ＭｅＶ的质子束为激发源，利用单元四极磁透镜对带电粒子束的单向聚束本领，对超导材料样品ＣａＳｒ２Ｂｉ２Ｃｕ２Ｏ８进行了扫描ＰＩＸＥ分析，获得了其中元素Ｘ射线强度的垂向分布数据。在没有质子数数据参数的情况下，针对这种样品组成已知的特殊性，采用了内标迭代定量分析方法，获得了各元素的垂向浓度分布结果。强度和浓度数据均表明，元素Ｃａ主要分布在样品的顶部表层，证明人们关于超导材料合成过程中存在重力效应影响的推断是正确的。

In order to study the gravitation effect in synthesis of superconducting materials, proton induced X ray emission technique with the proton source being focused to a line shaped beam (4 mm in horizontal and 0.5 mm in vertical) has been used to scan vertically a sample supposed to be CaSr 2Bi 2Cu 2O 8. A new quantitative method, namely the internal standard iteration method, also has been used to calculate the element concentrations without the data for proton numbers. The method, with the concentration of the internal standard being approximately known, is essentially a modification of the common internal standard method and is suitable to this special kind of samples in which the concentrations of the analytes sum to 100%. Both the elemental X ray intensity and concentration distributions show that Ca mainly presents in the upper area of the sample, while the other heavier elements show smoother distribution patterns. The results strongly suggest the existence of gravitation effect in the synthesis of superconducting materials.