摘要
提出一种理论计算结合实验测量来确定穆斯堡尔(Mossbauer)谱实验样品最佳厚度(dopt)的办法。在穆斯堡尔谱测量中,信噪比(Q)可用一个解析式来表示,其值随实验样品厚度的变化有一个极大值,它对应于样品的最佳厚度dopt.研究表明,要确定一个样品的最佳厚度dopt,除了清楚其化学成分外,若准确知道样品的无反冲分数fa,则可以直接通过理论计算来求dopt;否则,就要用本文介绍的办法来确定dopt。
Here is presented a method for calculating the optimum thickness dopt of an absorber in combination with the Mossbauer measurements. It is convenient to define a sig- nal-to-noise ratio (S/N) ,as a function expression of the absorber thickness ,this ratio reach- es a maximum value at optimum thickness dopt, corresponding the maximum Mosslsauer ef- fect and smaller statistical error. In the case of lacking the knowledge of recoilless fraction fa for a giren material ,a series of Mossbauer spectra with different absorber thickness must be carried out , and a fit Of the experiment data to the S/N ratio yields dopt . Our investigation shows that the S/N ratio excellently describe the experiment results ,so if fa is known accu- rarely .one can calculate dopt by using the S/N ratio without measurement process.
出处
《武汉大学学报(自然科学版)》
CSCD
1997年第3期348-352,共5页
Journal of Wuhan University(Natural Science Edition)
基金
国家教委留学回国人员科研启动基金
关键词
穆斯堡尔谱
最佳厚度
信噪比
样品
Mossbauer spectrum ,optimum thickness signal-to-ratio