Impact of digitization for timing and pulse shape analysis of scintillator detector signals

Abstract

In this paper we investigate the effects of full digitization of scintillator signals. The requirements on the analog to digital converter (ADC), in terms of sampling rate (fs) and bit resolution, are investigated. Two applications for scintillator detectors are studied, pulse timing and particle species identification. We find that signal reconstruction using sinc interpolation can be used e.g. for high-precision timing of a sampled electric pulse. Timing performances better than 6ps (FWHM) were obtained if fs equals or exceeds twice the maximum frequency of the scintillator pulse. Failing to meet this criterion deteriorates both the performance of pulse timing and particle identification. We find that the bit resolution of the ADC is very important also for timing of pulses.