A New Temperature Correction Method for NaI(Tl) Detectors Based on Pulse Deconvolution

Abstract

To overcome the temperature effect of NaI(Tl) detectors for energy spectrometry without additional hardware, a new correction method was put forward based on pulse deconvolution, trapezoidal shaping and amplitude correction, named DTSAC. To verify this method, actual pulses from a NaI(Tl)-PMT detector were measured at various temperatures from −20 °C to 50 °C. Pulse processing and spectrum synthesis showed that the position drift of the 137Cs 662 keV peak was less than 3 keV, and the corresponding resolution at 662 keV of the sum spectra ranged from 6.91% to 10.60% with the trapezoidal width set from 1000 ns to 100 ns. The DTSAC method corrects the temperature effect via pulse processing, and needs no reference peak, reference spectrum or additional circuits. The method solves the problem of correction of pulse shape and pulse amplitude at the same time, and can be used even at a high counting rate.

Temperature Peak-Drift Correction Method for NaI(Tl) Detectors Using the Background Peak

“…Another method involves correcting the PMT’s anode output waveform through signal processing. Modifications to subsequent circuits allow for the elimination of temperature-induced differences between radiation pulses through pulse deconvolution, trapezoidal shaping, and amplitude correction [ 8 ]. Additionally, adjusting the integration time to 385 ns instead of 1.23 µs mitigates temperature-dependent energy calculation, reducing spectral shift [ 9 ].…”