THE DEVELOPMENT OF SYNCHROTRON X-RAY AREA DETECTORS FOR STUDYING HIGH-PRESSURE PHASE-TRANSITIONS

Two detector systems are currently being developed for use with high pressure cells on beamline 9 at Daresbury Laboratory. The first is a television area x-ray camera which is used for rapid alignment and specimen characterisation. The second is an imaging plate system which is being developed to obtain accurate integrated intensities from small volume powder samples. The television detector has been used to determine lattice parameters to an accuracy of 1 x 10(-3) angstrom. The measured intensities compare well with data from the same specimen collected on film. The imaging plate system was used in the same configuration as the television detector and the film. The specimens studied were La2CuO4 and InSb. The early results from this detector show a great deal of promise especially in the low photon flux region which is essential for determining accurate intensities from weak Debye-Scherrer rings. A radial integration program for summing over the whole diffraction range is being developed.