150 NSEC ENCODING SR PROTEIN CRYSTALLOGRAPHY DETECTORS

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DESCRIPTION (Adapted from investigator's abstract): X-ray crystallography is the principal technique for studying the structure of biological proteins. Detailed knowledge of their conformational changes in the course of biochemical reactions such as enzyme activity are critical to a precise understanding of the relationships between chemical structure, physical topology and biochemical activity. Being transient, these intermediate states must be studied with time resolved crystallography. Upcoming storage rings will provide sufficient x-ray flux to study reactions in the time regime between msec and nsec, if integrating 2-D detectors can be devised which can be read out in the 150 nsec intervals between the 100 psec x-ray bursts emitted by these storage rings. High quality integrating detectors exist, (e.g. CCDs) but they are limited by their sequential readout schemes. This work addresses the readout problem by developing a method to process all the pixels of a 2-D detector (1 frame) in parallel, digitizing and storing the values in local memory until the end of an experiment, about 1000 frames, when all the data are dumped to permanent storage at normal data bus rates. In this Phase II effort these concepts will be implemented in a 1-D detector having a "stackable" geometry which will establish an approach to 2-D detector assembly in Phase III.