正电子湮没辐射多普勒展宽谱的处理及其应用  

Processing of Doppler broadening spectra of positron annihilation radiation and its application

作　　者：郑万辉[1] 彭郁卿[1] 张怡萍[1] 王景成[2] 

机构地区：[1]中国科学院上海原子核研究所 [2]上海钢铁研究所

出　　处：《核技术》1991年第4期200-206,共7页Nuclear Techniques

摘　　要：用迭代法对湮没辐射的Doppler展宽谱去卷职,获取湮没辐射的本征分布。用高斯—牛顿法将本征分布拟合为一个高斯函数(心电子贡献)和抛物线函数(传导电子贡献)之和。从本征分布和抛物线函致可以算出电子的动量分布信息和估测费米能。用纯Ge探测器测量了Al、Ag、Cu、Co、Ni、Sa、In、Mo、W、Zr,Ti、Ge、Si等13种材料的多普勒展宽谱,算出它们的动量分布和费米能,显示各种材料的动量分布明显不同,由实验测得的费米能值与由自由电子气模型计算的理论值很好符合。对Fe Si B非晶和晶态合金的研究表明:两者的动量分布差异甚小,但费米能略有不同。An unfolding method to obtain intrinsic distributions of positron annihilation radiation from Doppler broadening spectra by means of an iterative method is described. The intrinsic distribution can be fitted into a Gaussian function and an invert parabola function. Electron momentum distribution and Fermi energy can be calculated.Positron annihilation spectra for 13 materials were analyzed. Their momentum distribution and Fermi energy were obtained. The results show that electron momentum distributions for various materials are different and experimental values of Fermi energy for various materials are consistent with theoretical ones. The study on amorphous and crystalline Fe-Si-B alloys indicates that momentum distributions are almost the same, while there is a small difference on Fermi energy.

关 键 词：正电子湮没 多普勒展宽谱 费米能 

分 类 号：O572.322[理学—粒子物理与原子核物理]