A large high counting rate one-dimensional position sensitive detector: The D20 banana

The D20 high flux two-axis diffractometer is a versatile instrument, particularly suited for real-time measurements. So it demands a large, curved and stationary one-dimensional position sensitive detector for high counting rates with a fast data acquisition system. It uses microstrips, deposited on glass plates, as detection electrodes. Each of these 1600 cells is constituted of four basic microstrips and has its own output from the detector to one of the 1600 amplifiers, followed by 1600 anti-coincidence logics and a parallel input to the data acquisition system. The counting rate limitation is about 50 000 counts/s/cell.