A device for coupling a pulse height discriminator to a scanning X-ray spectrometer

Abstract

A simple control device has been developed to synchronize a single-channel pulse height discriminator with the rotation of the crystal in an X-ray spectrometer over an energy range of 1: 8. Both the bias voltage and the window width of the discriminator are continuously adjusted. The spectrometer had a 50 kV tungsten target X-ray tube, an LiF analysing crystal and a scintillation counter. With this arrangement the line-to-background ration for a wavelength of about 2.8 A is improved by a factor of 33 compared with results obtained without a discriminator. Second-order reflections were attenuated within the whole waveband 0.35 2.8 A by a factor of at least 60, and third-order reflections by a factor of at least 400.