The Wave-Lengths of the Silver, Molybdenum, Copper, Iron and ChromiumKα1Lines

Abstract

It has been shown that a double crystal spectrometer can be used to measure x-ray wave-lengths with a precision as great or greater than that obtained by the usual methods. The purpose of the present work was to determine the x-ray wave-lengths of several important lines by using such a spectrometer, and to compare the results with the most precise values which have been obtained by other methods. From two to five orders have been measured in each case, but in the following table only the order which was given greatest weight has been listed. The results on the silver and molybdenum $K{\alpha }_1$ lines, which are symmetrical lines, agree satisfactorily with the results obtained by the photographic methods. The $K{\alpha }_1$ lines of copper, iron and chromium which were found to be asymmetrical differ considerably from the results of photographic methods. Most of the other lines of the copper, iron and chromium $K$ series were also found to be asymmetrical. Thus it appears that the double crystal spectrometer has a decided advantage in the measurement of wave-lengths of such lines.