A high rate gaseous area detector for X-ray diffraction applications

A new photon-counting area detector based on parallel-plate gas amplification with a resistive anode and remote readout electrode is described. The detector is sealed and has a sensitive area of 14x14 cm(2). The detector is unique in its ability to achieve high gain at high counting rates. A local counting rate >10(5) counts/mm(2)-sec has been achieved at a gain of up to 10(5) in a radiation-hard, non-polymerizing gas mixture. The global readout rate is limited by the delay line and electronics to <10(6) counts/sec but more sophisticated readout schemes should allow this rate to be increased by more than an order of magnitude. The operating characteristics of the detector are described and preliminary x-ray diffraction data is presented.