Soft X-Ray Photon Detection and Image Dissection Using Channel Multipliers

Abstract

The use of channel multipliers for the photo-electric detection of X-radiation in the wavelength range 2.1 - 67 Å has been investigated. Measurements of photon detection efficiency are presented for a bare channel multiplier and for multipliers specially coated with photoemissive materials. The variation of photon detection efficiency with angle of incidence is shown to be in fair agreement with that predicted by an analysis of the X-ray photo-electric response of a cylindrical photo-cathode. The surface yields derived from the measurements for Li F and MgF2 are compared with other published data, based on plane photo-cathode measurements, and shown to be in good agreement. A specific application of the channel multiplier in X-Ray Astronomy is described. The results of an investigation into the X-ray response and spatial resolution of a channel multiplier array are also presented. The measured resolution is close to the expected value. The application of arrays of channel multipliers to image dissection in X-ray spectroscopy is discussed.