The applications of X-ray emission or fluorescent spectrography to chemical analysis have increased spectacularly in recent years, but little attention has been paid to the potentialities of X-ray absorption techniques. Monochromatic X-ray absorption-edge spectrometry, in particular, is most promising. The ultimate sensitivity of absorption-edge spectrometry probably will be less than that of fluorescent analysis, but this disadvantage may be outweighed by the convenience, economy, and absence of matrix effects with the former method. Both methods appear limited in application only to certain elements.

A pulse height analyzer coupled with scintillation and proportional counter detection has been found to permit an increase in sensitivity of absorption-edge spectrometry, primarily because controlled window widths may be utilized in determining transmitted X-ray intensities with a sealer. Further work has led to the development of a new rapid, convenient technique known as “differential pulse amplitude distribution (PAD) peak height analysis.” Work carried out during the development of the new method is described.