An Improved Source for the Lyman Continuum in the Vacuum Ultraviolet

An improved design of Lyman discharge tube, a well-known high intensity source of continuous radiation, is described. The usual mechanical difficulties are largely avoided by use of a replaceable quartz capillary held in permanent alignment by a metal clip, and of a fin-type electrode that effectively prevents clogging of the spectrograph slit even for widths as narrow as 0.02 mm. Some features of the operation of the source are discussed.