SIMPLE RADIAL POSITION-SENSITIVE DETECTOR WITH SHORT DEADTIME FOR TIME-OF-FLIGHT AND COINCIDENCE EXPERIMENTS

A simple one-dimensional position-sensitive detector using delay-line encoding to achieve deadtimes below 100 ns for groups of particles is presented. The design allows for trade-off between positional resolution, deadtime and the number of particles per group. The prototype performance (1 mm resolution, 100 ns deadtime for up to four particles) has been tested in applications to dissociative single and double photoionisation of small molecules. The forward/backward electron ejection asymmetry in NO photoionisation to NO + (c3 Pi ) and an axial/transverse asymmetry on O 2 photoionisation are confirmed.