Fast Electronics for Scintillation Counter Systems in Space Experiments

Fast coincidence and analog electronics have been developed to process signals from the scintillation and Cherenkov detectors of the triggering telescope, which forms part of the COS-B experiment for gamma ray astronomy. Design requirements and solutions for the electronics are presented, and the performance is discussed. Integrated circuits have been used extensively in order to minimise the number of components, hence volume and weight, and to optimise the reliability. The goals of a time resolution down to 3ns for a dynamic range of 1 to 30, a signal processing time of 200ns for timing and 500ns for analog analysis, a maximum temperature instability of the trigger thresholds of 2% of the typical signal amplitude over a range of 50°C and a maximum non-linearity of 1% of full scale for the pulse height analysis have been achieved.