Modified phase-only correlator for pileup correction for gamma-ray spectrometry

A new algorithm for gamma-ray spectrometry is proposed in this paper which is suitable for pileup correction at very high count rates of 4 × 10⁶ pulses/s. Parameters of the overlapped pulses from the detector including both starting time and amplitude are estimated by the proposed algorithm which combines modified phase-only correlator (MPOC) with Kurtosis-based amplified noise suppression (KANS) algorithm and maximum likelihood estimation (MLE) method. Algorithms are further modified to improve performance under low SNRs, because of the critical dependency of MPOC with KANS algorithm on SNR. The algorithms are evaluated on a simulated ⁶⁰Co spectrum generated at high counting rate. Simulation results show that our algorithms preserve high resolution of energy spectrum at high counting rates.