An investigation of multilayer soap crystals for ultra soft x-ray spectrometry.

The extension of conventional monochromating techniques into the ultra soft x-ray region has been discussed. The use of large spacing pseudo crystals has been considered with particular reference to multilayer soap crystals. In an attempt to produce these crystals with the best possible x-ray reflection characteristics a detailed analysis of the building process and the associated parameters has been carried out. A specially constructed plane crystal spectrometer was used to obtain new extensive absolute reflectivity data for these optimised crystals. The results show that the crystals have an unusual structure exhibiting considerable imperfection. New reflectivity data for potassium acid phthalate (K.A.P.) crystals has also been obtained. Proportional counter detection was used throughout this work and in this connection proportional counter resolution has been studied in some detail. The importance of anode wire uniformity has been investigated in more detail than previously reported. By using a very smooth anode wire better resolution measurements have been obtained, in the 0.2-10 k.e.v. photon energy region, than reported in any previously published data.