A Displacement in the N Lines of Tungsten and Tantalum

Abstract

WE have recently conducted some experiments on the characteristic radiations of various elements in the extreme soft X-ray region. Spectra have been obtained with the aid of a vacuum spectrograph employing a plane Siegbahn grating in the grazing incidence setting. Using a water-cooled anti-cathode, on to which tungsten was sputtered from the hot filament of the X-ray tube, we have obtained lines at 55.58 and 58.42 A. Thibaud and Soltan ¹ have previously obtained wave-lengths of 56.0 and 59.1 A., while Prins,² who, in addition to using this procedure, has apparently employed a water-cooled tungsten anti-cathode, has recently published values of 55.7 and 58.4 A., with which our results are in good accord.