IC 7725 Conversion Tables For Fluorescent X-Ray Spectroscopy - Introduction

The possibility of chemical analysis by identification of characteristic X-ray spectral lines was first suggested by H. C. J. Moseley in 1913.3/ For a given spectral series it was found that the frequency of the characteristic radiation was proportional to the square of the atomic number of the excited atom. Siegbahn and his coworkers improved the instrumentation and accurately determined the wavelengths of the characteristic spectra for most of the elements .4/ In fluorescent X-ray spectroscopy, the characteristic X-rays of atoms are emitted or fluoresced upon absorption of primary or incident X-rays of shorter wave-lengths (higher energies). The K spectral lines are used for elements of atomic numbers 13 to about 63, and the L series for those above atomic number 50. Whether the K or L lines are used for elements 50-63 depends upon the type of instrumentation available. The laboratory at the Eastern Experiment Station of the Bureau of Mines, College Park, Md., uses the K lines up to atomic number 57 and the L lines for thong elements of higher atomic number.