Blind source separation of HPGe output signals: a new pulse pile-up correction method

Abstract

The pulse pileup phenomenon is one of the major problems of the gamma-ray spectrometry, especially at high counting rates. This phenomenon is considered herein, in signal processing point of view, as a blind source separation problem. Indeed, we present in this paper the application of the symetric prewhitening algorithm for the separation of overlapping pulses. The obtained results show that we can achieve the separation task using only three preamplifier's recordings. In case of pulse pileup , the algorithm allows to separate the stacked pulses into two independent components. A third component is also extracted. This last was found to be strongly correlated to the detector's background noise. Otherwise, the algorithm permits to identify two independent components.

Neutron Flux Monitoring Based on Blind Source Separation Algorithms in Moroccan TRIGA MARK II Reactor

“…The application of new digital signal processing methods, the so-called Blind Source Separation (BSS), on nuclear data was introduced by Mekaoui et al [7][8][9]. It was used, as mentioned above, for the detection and identification of gamma radiation emitters and for solving the pileup problem at the output of HPGe preamplifier used in gamma spectrometry chains.…”

“…Thus, their work aims at detecting and identifying gamma-emitters using only the signals recorded at the HPGe preamplifier's output signals [7,8]. Also, they tried to solve the pileup problem at the HPGe output [7,9]. This encouraged us to apply these powerful signal processing algorithms to control the neutron flux in Moroccan TRIGA MARK II Reactor.…”