Simulation of the Effect of Capacitive Decay of Detector-Circuit on the Detector Response

Abstract

In order to understand the effect of capacitive decay due to detector-circuit on the detector response, we have carried out Monte Carlo simulations of the response of pulse-type two-electrode parallel plate ionization chambers, gridded parallel plate ionization chambers and fully depleted silicon surface barrier detectors. These simulations have been carried out incorporating the physical processes, namely, emission of charge carriers by ionization in the detector medium, separation and acceleration of the charge carriers, transport of the charge carriers, induction of charges on the electrodes, shaping of the pulses, etc. Simulations show that the capacitive decay due to detector-circuit during the motion of charge carriers in the detector medium produces appreciable loss in the pulse height, when the time constant of the detector-circuit is of the order of charge collection time in the detector.